WO2025117719A1 - Silicone-polyester copolymers and adhesive compositions including the same - Google Patents

Abstract

A silicone-polyester copolymer includes the reaction product of: a branched silicone diol containing at least one branched silicone group and a dicarboxylic acid. The silicone-polyester copolymer has a molar ratio of units derived from the branched silicone diol to units derived from the dicarboxylic acid of at least about 0.05:1. Moreover, the silicone-polyester copolymer has a weight average molecular weight of at least about 25,000 Daltons.

Description

SILICONE-POLYESTER COPOLYMERS AND ADHESIVE COMPOSITIONS INCLUDING THE SAME

TECHNICAL FIELD

[0001] The present disclosure generally relates to silicone-polyester copolymers and adhesive compositions including the same. More particularly, the present disclosure relates to silicone-polyester copolymers for pressure sensitive adhesive applications.

BACKGROUND

[0002] Pressure sensitive adhesives (PSAs) are materials that adhere to a surface under light pressure and do not require the application of heat or solvent to form a bond. PSAs generally include specialized polymers that exhibit viscoelastic properties at ambient temperature, meaning that they exhibit both viscous (flow) and elastic (recovery) responses to applied stress. PSAs are used in a wide range of applications, including labeling, packaging, medical products, and automotive parts. Various different types of chemistries can be used in the formulation of PSAs, each with their own benefits and drawbacks. For example, acrylic-based PSAs may offer excellent weather resistance, shear strength, and long-lasting adhesion to a wide range of surfaces. Polyisobutylene and polyurethane-based PSAs may offer excellent moisture management. Rubber-based PSAs may offer excellent initial tack and conformability. Silicone- based PSAs may exhibit excellent release properties, high-temperature resistance, and biocompatibility, making them ideal for medical and electronic applications. However, many existing PSAs do not offer combinations of beneficial properties.

[0003] Copolymers derived from silicone-containing monomers and organic monomers, such as alcohols and carboxylic acids, offer a range of benefits making them suitable for use in a variety of applications, including coatings, adhesives, lubricants, and more, with combined benefits provided that are traditionally associated with the silicone-based chemistries and the organic chemistries. However, such previously developed copolymers present their own challenges. For example, sugar-siloxane copolymers have been proposed, but they generally exhibit poor adhesion properties. Silicone-acrylate copolymers have been developed, but undesirably require incorporation of organic solvent.

[0004] Polyester-silicone copolymers have been explored but with limited success for adhesive applications. Such efforts have involved reacting dicarboxylic acids with hydroxyfunctional silicones. However, due to poor miscibility between the dicarboxylic acids and hydroxy-functional silicones, the hydroxy-functional silicones tend to not participate in polymerization as the polymer chain grows. As a result, insufficient weight average molecular weight (Mw) is achieved for the copolymers, resulting in poor cohesion and viscoelastic properties. Furthermore, phase separation generally renders such copolymers non-adhesive.

[0005] Accordingly, it is desirable to provide hybrid organic-silicone copolymers that can be suitable for pressure sensitive adhesive applications, with excellent viscoelastic properties, smooth adhesion and drug release performance, as well as excellent cohesiveness and hot melt performance. In addition, it is desirable to provide organic-silicone copolymers with relatively high content of silicone moieties to exploit benefits associated with silicone-based PSAs. Furthermore, other desirable features and characteristics of the present disclosure will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background.

BRIEF SUMMARY

[0006] This disclosure provides a silicone-polyester copolymer including the reaction product of: a branched silicone diol containing at least one branched silicone group and a dicarboxylic acid. The silicone-polyester copolymer has a molar ratio of units derived from the branched silicone diol to units derived from the dicarboxylic acid of at least about 0.05: 1. Moreover, the silicone-polyester copolymer has a weight average molecular weight of at least about 25,000 Daltons.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The present disclosure will hereinafter be described in conjunction with the following drawing figures, wherein:

[0008] FIG. 1 is a line graph of Storage Modulus and Loss Modulus, each as a function of angular frequency, of Example 3 at 30°C;

[0009] FIG. 2 is a line graph of Storage Modulus and Loss Modulus, each as a function of angular frequency, of Example 4 at 30°C;

[0010] FIG. 3 is a line graph of Storage Modulus and Loss Modulus, each as a function of angular frequency, of Example 5 at 30°C; and

[0011] FIG. 4 is a line graph of Storage Modulus and Loss Modulus, each as a function of angular frequency, of Example 6 at 30°C.

DETAILED DESCRIPTION [0012] The following detailed description is merely exemplary in nature and is not intended to limit the present disclosure or the application and uses thereof. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.

[0013] Embodiments of the present disclosure are generally directed to silicone-polyester copolymers and adhesive compositions including the same and methods for forming the same. For the sake of brevity, conventional techniques related to making such copolymers and such compositions may not be described in detail herein. Moreover, the various tasks and process steps described herein may be incorporated into a more comprehensive procedure or process having additional steps or functionality not described in detail herein. In particular, various steps in the manufacture of copolymers and associated compositions are well-known and so, in the interest of brevity, many conventional steps will only be described briefly herein or will be omitted entirely without providing the well-known process details.

[0014] In this disclosure, the terminology “about” can describe values ± 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10%, in various embodiments. Moreover, it is contemplated that, in various nonlimiting embodiments, it is to be appreciated that all numerical values as provided herein, save for the actual examples, are approximate values with endpoints or particular values intended to be read as “about” or “approximately” the value as recited. It is also contemplated that all isomers and chiral options for each compound described herein are hereby expressly contemplated for use herein in various non-limiting embodiments.

[0015] Throughout this disclosure, the terminology percent "actives" is well recognized in the art and means the percent amount of active or actual compound or molecule present as compared to, for example, a total weight of a diluted solution of a solvent and such a compound. Some compounds, such as a solvent, are not described relative to a percent active because it is well known to be approximately 100% actives. Any one or more of the values described herein may be alternatively described as percent actives as would be understood by the skilled person. [0016] In various embodiments, the terminology “free of’ describes embodiments that include less than about 5, 4, 3, 2, 1, 0.5, or 0.1, weight percent (or weight percent actives) of the compound or element at issue using an appropriate weight basis as would be understood by one of skill in the art. In other embodiments, the terminology “free of’ describes embodiments that have zero weight percent of the compound or element at issue. [0017] The terminology “consists essentially of’ may describe various non-limiting embodiments that are free of one or more optional compounds described herein and/or free of one or more compounds, polymers, surfactants, additives, solvents, etc. known in the art.

[0018] It is to be understood that the subscripts of copolymers are typically described as average values because the synthesis of copolymers typically produces a distribution of various individual molecules.

[0019] The copolymers and compositions disclosed herein may suitably comprise, consist of, or consist essentially of the components, elements, and process delineations described herein. The embodiments illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein.

Silicone-Polyester Copolymers

[0020] This disclosure provides a silicone-polyester copolymer includes the reaction product of a branched silicone diol containing at least one branched silicone group and a dicarboxylic acid. In various embodiments, the copolymer is or includes, consists essentially of, or consists of the aforementioned reaction product. In various embodiments, the copolymer consists essentially of the aforementioned reaction product and is free of, or includes less than about 0.5, 0.4, 0.3, 0.2, 0.1, or 0.05, weight percent of, other polymers, co-polymers, monomers, etc. The terminology "dicarboxylic acids' as used herein, includes equivalents of dicarboxylic acids having two functional groups which perform substantially like dicarboxylic acids in reaction with glycols and diols in forming co-polyetherester polymers. These equivalents can include esters and ester-forming derivatives, such as acid anhydrides.

[0021] The silicone-polyester copolymer has a molar ratio of units derived from the branched silicone diol to units derived from the dicarboxylic acid of at least about 0.05: 1. Moreover, the silicone-polyester copolymer has a weight average molecular weight of at least about 25,000 Daltons. The molecular weight requirement pertains to the acid and not to its equivalent ester or ester-forming derivative.

[0022] The silicone-polyester copolymers are suitable for various applications including pressure sensitive adhesive applications as well as thermoplastic elastomer applications. The silicone-polyester copolymers exhibit excellent viscoelastic properties and combined performance benefits that have traditionally been associated with polyester-based PSAs or silicone-based PSAs, respectively, due to the relatively high Mw of the copolymer and presence of a relatively high content of branched silicone moieties in the copolymer. In particular, the dicarboxylic acid provides a hard phase of the copolymer, which contributes to cohesiveness and hot melt performance while the branched silicone moiety provides a soft phase that promotes smooth adhesion and can be loaded with pharmaceuticals for topical release. Without being bound by theory, it is believed that the branched silicone moiety contributes to enhanced miscibility between the dicarboxylic acid and the branched silicone diol, which enables higher Mw to be achieved for the resulting copolymers as compared to known organic-silicone copolymers. With higher Mw achievable for the subject copolymers, complications with phase separation and lack of adhesiveness (due to poor viscoelastic properties) can be avoided and the benefits traditionally associated with only polyester-based or only silicone-based PSAs can be realized.

[0023] In various embodiments, the silicone-polyester copolymers and associated pressure sensitive adhesives are useful for adhesives in wound care and various health care applications wherein adhesion to skin and/or medical devices or implements are used.

[0024] The present disclosure also provides a pressure sensitive adhesive including the silicone-polyester copolymer.

[0025] The present disclosure also provides a dermal patch including the pressure sensitive adhesive, wherein the dermal patch is typically a transdermal drug delivery patch or a wound care patch.

[0026] The present disclosure also provides a medical device including the pressure sensitive adhesive.

[0027] In various embodiments, the silicone-polyester copolymer includes the following structure:

wherein: R¹, R², and R³ are each independently chosen from C1-C4 aliphatic groups or -OSiRⁿ3 wherein R¹¹ is a C1-C4 aliphatic group, provided that at least two of R¹, R², or R³ are -OSiR¹¹?; x is from 1 to 4; y is from 1 to 3;

R⁴ is H or a C1-C4 alkyl group;

R⁷ is chosen from C6-C12 aromatic groups or C4-C10 aliphatic groups;

R⁸ is chosen from Ci-Ce aliphatic groups and/or linear poly(alkylene oxide) and/or linear polysilicone

R⁹, and R¹⁰ are each independently chosen from C1-C4 aliphatic groups; a is from about 1 to about 30; and b is from about 1 to about 30.

For example, x may be 1, 2, 3, or 4. Y may be 1, 2, or 3. Each of a and b may independently be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30. In various non-limiting embodiments, all values and ranges thereof, including and between those set forth above, are hereby expressly contemplated for use herein.

[0028] In various embodiments, the silicone-polyester copolymer includes a total of at least 2 units derived from the branched silicone diol and 2 units derived from the dicarboxylic acid. [0029] Moreover, the silicone-polyester copolymer has a weight average molecular weight of at least about 25,000 Daltons. In various embodiments, the weight average molecular weight is at least about, or may be a maximum of about, 50,000, 100,000, 150,000, 200,000, 250,000, 300,000, 350,000, 400,000, 450,000, 500,000, 550,000, 600,000, 650,000, 700,000, 750,000, 800,000, 850,000, 900,000, 950,000, or 1,000,000, Daltons. In still other embodiments, the weight average molecular weight is from about 100,000 to about 250,000, about 125,000 to about 225,000, about 150,000 to about 200,000, or about 150,000 to about 175,000, Daltons. Alternatively, the weight average molecular weight may be from about 25,000 to about 500,000, about 50,000 to about 500,000, about 100,000 to about 450,000, about 150,000 to about 400,000, about 200,000 to about 350,000, or about 250,000 to about 300,000, Daltons. In various nonlimiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[0030] Typically, weight average molecular weight, as described herein, is determined using standard techniques such as GPC (gel phase chromatography). Molecular weight, average molecular weight, and dispersity are typically determined by GPC analysis with calibration according to UV absorption at 254 nm. Molecular weights are typically determined by calibration to narrow polymethylmethacrylate molecular weight standards.

Branched Silicone Diol

[0031] As first described above, the silicone-polyester copolymer includes the reaction product of the branched silicone diol containing the at least one branched silicone group and the dicarboxylic acid.

[0032] The branched silicone diol may be any known in the art. In various embodiments, the branched silicone diol has a weight average molecular weight of from about 300 Daltons to about 1500 Daltons, for example of from about 350 to about 1450, about 400 to about 1400, about 450 to about 1350, about 500 to about 1300, about 550 to about 1250, about 600 to about 1200, about 650 to about 1150, about 700 to about 1100, about 750 to about 1050, about 800 to about 1000, about 850 to about 950, or about 900 to about 950, Daltons. In various nonlimiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[0033] In other embodiments, the branched silicone diol has the formula:

wherein:

R¹, R², and R³ are each independently chosen from C1-C4 aliphatic groups or - OSiR^U3 wherein R¹¹ is a C1-C4 aliphatic group, provided that at least two of R¹, R², or R³ are -OSiR¹^ x is from 1 to 4; y is from 1 to 3;

R⁴ is H or a C1-C4 alkyl group; and

R³ and R⁶ are each independently chosen from C1-C4 aliphatic groups.

[0034] For example, each of R¹, R², R³, and R¹¹ may independently be an aliphatic group that has 1, 2, 3, or 4 carbon atoms pursuant to the proviso above. Moreover, x may be 1, 2, 3, or 4. In addition, y may be 1, 2, or 3. R⁴ may be H or may alternatively be an aliphatic group that has 1, 2, 3, or 4 carbon atoms. Similarly, each of R⁵ and R⁶ may independently be an aliphatic group that has 1, 2, 3, or 4 carbon atoms. In still other embodiments, two of R¹, R², or R³ are -OSiRⁿ3; one of R¹, R², or R³ is methyl; R¹¹ is methyl; x is 3; y is 1; R⁴ is ethyl; and R⁵ and R⁶ are methylene groups. In various non-limiting embodiments, all values and ranges thereof, including and between those set forth above, are hereby expressly contemplated for use herein.

[0035] Without intending to be bound by any particular theory, it is believed that the choice of the branched silicone diol contributes to superior and unexpected adhesion properties. Moreover, short chain branched diols have been found to yield superior and unexpected compatibilization in polyester polymerization reactions which allow for production of copolymers with higher than expected molecular weights.

Dicarboxylic Acid

[0036] Referring now to the dicarboxylic acid, this component may be any known in the art. In one embodiment, the dicarboxylic acid is an aliphatic dicarboxylic acid. In another embodiment, the dicarboxylic acid is an aromatic dicarboxylic acid.

[0037] In various embodiments, the dicarboxylic acid is chosen from terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, phthalic acid or phthalic anhydride, cyclohexanedicarboxylic acid, biphenyl dicarboxylic acid, any of the series of C4-C10 aliphatic dicarboxylic acids, a spiroacetal diacid, or a combination thereof. In one embodiment, the dicarboxylic acid is terephthalic acid. In another embodiment, the dicarboxylic acid is isophthalic acid. In another embodiment, the dicarboxylic acid is naphthalenedicarboxylic acid. In another embodiment, the di carboxylic acid is phthalic acid or phthalic anhydride. In another embodiment, the dicarboxylic acid is cyclohexanedicarboxylic acid. In another embodiment, the dicarboxylic acid is caprolactone. In another embodiment, the dicarboxylic acid is lactide. In another embodiment, the dicarboxylic acid is glycolic acid. In another embodiment, the dicarboxylic acid is a polymer or copolymer of any of the above dicarboxylic acids. In another embodiment, the dicarboxylic acid is polyhydroxyalkanoate. In another embodiment, the dicarboxylic acid is biphenyl dicarboxylic acid. In another embodiment, the dicarboxylic acid is chosen from C4-C10 aliphatic dicarboxylic acids, e.g. those that have 4, 5, 6, 7, 8, 9, or 10 carbon atoms. In another embodiment, the dicarboxylic acid is a spiroacetal diacid.

[0038] In one embodiment, the at least one dicarboxylic acid includes an aromatic dicarboxylic acid chosen from one or more of terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid. In another embodiment, the at least one dicarboxylic acid is terephthalic acid. In another embodiment, the aromatic dicarboxylic is a derivative of benzimidazole, isobenzoxazole or acridone.

[0039] Without intending to be bound by any particular theory, it is believed that the choice of the dicarboxylic acid influences the presence of crystalline segments in the backbone of the copolymer which, in turn, influences the cohesive strength of the copolymer and the final composition.

Reaction of the Branched Silicone Diol and the Dicarboxylic Acid

[0040] Typically, the branched silicone diol and the dicarboxylic acid react via an polyesterification/esterification type of reaction. This reaction type is well known in the art and may be completed using any temperatures, pressures, and times that would be chosen by the skilled person. Typically, the reaction conditions include reaction under vacuum at a temperature of from about 180 to about 260°C and for a time of minutes to hours, as is understood by the skilled person.

[0041] Typically, the branched silicone diol and the di carboxylic acid react in amounts such that the silicone-polyester copolymer has a molar ratio of units derived from the branched silicone diol to units derived from the dicarboxylic acid of at least about 0.05: 1. In various embodiments, the maximum ratio is about 1 : 1. In other embodiments, the ratio may be about (0.05 to about 1):1, (0.1 to 0.9): 1, (0.2 to 0.8): 1, (0.3 to 0.7): 1, (0.4 to 0.6): 1, or about (0.5): 1. In still other embodiments, the ratio is about (0.15 to 0.3): 1, (0.2 to 0.3): 1, (0.25 to 0.3): 1, (0.15 to 0.25): l, or (0.15 to 0.2): l. In other embodiments, the silicone-polyester copolymer has a molar ratio of units derived from the branched silicone diol to units derived from the dicarboxylic acid of from about 0.1 : 1 to 1 : 1. In other embodiments, the copolymer has a molar ratio of units derived from the aliphatic diol to units derived from the dicarboxylic acid of from about 0.1 : 1 to about 0.8: 1. In various non-limiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[0042] Without intending to be bound by theory, it is believed that the choice of ratio contributes to adhesion vs cohesion balance in the copolymer and a final composition.

Alternative Embodiments

[0043] In various embodiments, as introduced above, the copolymer is or includes the reaction product of the branched silicone diol containing the at least one branched silicone group and the dicarboxylic acid. However, this disclosure also provides additional embodiments wherein the copolymer is or includes, consists essentially of, or consists of one or more of the following reaction products. It is contemplated that the copolymer may include any one of the reaction products described herein to the exclusion of any one or more other reaction products described herein. Alternatively, the copolymer may include two or more reaction products described herein. In various embodiments, the copolymer consists essentially of one or more of the following reaction products and is free of, or includes less than about 0.5, 0.4, 0.3, 0.2, 0.1, or 0.05, weight percent of, other polymers, co-polymers, monomers, etc.

[0044] In one embodiment, the reaction product is further defined as the reaction product of the branched silicone diol containing the at least one branched silicone group; the dicarboxylic acid; a dihydroxy-terminated polymeric diol different from the branched silicone diol; and/or an aliphatic diol having from 2 to 8 carbon atoms, e.g. 2, 3, 4, 5, 6, 7, or 8 carbon atoms. Any dihydroxy-terminated polymeric diol different from the branched silicone diol known in the art may be utilized. Similarly, any aliphatic diol having from 2 to 8 carbon atoms known in the art may be used. Inclusion of these diols can alternatively increase the softness of the copolymer as in the case of increasing polymeric diol content for polymeric diols with glass transitions below room temperature, or increase cohesive strength for various aliphatic diols.

[0045] In various embodiments, the dihydroxy-terminated polymeric diol is chosen from poly(alkylene oxide)diols (such as polyethylene oxide, polypropylene oxide, or polybutylene oxide, diols), linear aliphatic polyesters, linear aliphatic polycarbonates, linear polyadipates, linear polyether polysilicone diols, branched polyether polysilicone diols, and mixtures thereof. [0046] In other embodiments, the dihydroxy-terminated polymeric diol includes a linear polyether polysilicone diol having a weight average molecular weight of at least 800 Daltons and the poly silicone moiety is at least 30 weight percent of the linear poly ether poly silicone diol.

[0047] In various embodiments, the weight average molecular weight of the linear polyether polysilicone diol is from about 500 to about 10,000, about 1000 to about 9500, about 1500 to about 9000, about 2000 to about 8500, about 2500 to about 8000, about 3000 to about

7500, about 3500 to about 7000, about 4000 to about 6500, about 4500 to about 6000, about

5000 to about 5500, about 800 to about 4000, about 1000 to about 4000, about 1500 to about

3500, about 2000 to about 3000, or about 2000 to about 2500, Daltons. Typically, the higher the weight average molecular weight, the more problems with miscibility in the polymerization reaction can be observed. In various non-limiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[0048] Alternatively, the polysilicone moiety may be at least about 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, or 95, weight percent of the linear polyether polysilicone diol. In various non-limiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[0049] In still other embodiments, the copolymer has the formula:

wherein c is from about 1 to about 30; d is from about 0 to about 20; and g is from about 3 to about 50 and wherein R¹² and R¹³ are each independently chosen from C1-C4 aliphatic groups. For example, c may be 1 or any number up to about 30. D may be about 0 or any number up to about 20. G may be 3 or any number up to about 50. In various non-limiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[0050] In still other embodiments, the reaction product is further defined as the reaction product of: the branched silicone diol containing the at least one branched silicone group; the dicarboxylic acid; and an aliphatic diol chosen from 1,2-ethanediol; 1,3-propanediol; 1 ,4- butanediol; 1,5-pentanediol; 1,6-hexanediol; 2-methyl-l,3-propanediol; 2, 2-dimethy- 1,3- propanediol; 1,2-dihydroxy cyclohexane; 1,3 -dihydroxy cyclohexane; 1,4-dihydroxy cyclohexane; 1,4-butenediol; di ethyleneglycol; and mixtures thereof. In related embodiments, the copolymer has a molar ratio of units derived from the aliphatic diol to units derived from the dicarboxylic acid of from about 0.1: 1 to about 0.8: 1, about 0.2: 1, about 0.3:1, about 0.4: 1, about 0.5: 1, about 0.6:1 , about 0.7: 1 , about 0.8: 1, about 0.9: 1, or about 1 :1. In various nonlimiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[0051] In a typical embodiment, the polyester copolymer is linear in structure. Typical polyester copolymers may optionally include residues of monomeric long-chain branching agents to improve melt strength and melt viscoelasticity. Such branching agents may include pentaerythritol, trimethylolpropane, glycerol, trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), organic anhydrides, epoxides, isocyanates, and combinations thereof. Especially typical branching agents include 3,3', 4,4'-biphenyl tetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride, diphenyl sulfone tetracarboxylic dianhydride, pyromellitic dianhydride, trimellitic acid, pyromellitic acid, cyclopentane tetracarboxylic dianhydride, tetrahydrofuran tetracarboxylic dianhydride, 1 , 1 ,4,4-tetrak is(hydroxymethyl)cyclohexane, hydroxyterephthalic acid, dimethyl hydroxyl terephthalate, dihydroxybenzoic acid, 1.2.2-ethanetricarboxylic acid, triglycidyl isocyanurate, and combinations thereof. 0.043 Polymeric branching agents can also be utilized such as copolymers of ethylene or C-olefins with acrylic acid, vinyl acetate, an alkyl acrylate, vinyl alcohol, alkyl methacrylate, maleic anhydride, glycidyl methacrylate, and combinations thereof. Especially typical polymeric branching agents include poly(ethylene-8% acrylic acid), poly(ethylene-4% vinyl acetate), poly(ethylene-8% alkyl acrylate), poly(ethylene 56% vinyl alcohol), poly(ethylene-15% methacrylic acid, Nasalt), poly(ethylene-15% alkyl methacrylate), and combinations thereof.

Adhesive Composition

[0052] This disclosure also provides an adhesive composition. The adhesive composition may be, include, consist essentially of, or consist of the copolymer. Alternatively, the adhesive composition may be, include, consist essentially of, or consist of the copolymer and one or more additives described below. In various embodiments, the adhesive composition consists essentially of the copolymer and one or more of the additives described below and is free of, or includes less than about 0.5, 0.4, 0.3, 0.2, 0.1, or 0.05, weight percent of, other polymers, copolymers, monomers, optional additives that may or may not be described below, etc.

[0053] In various embodiment, the adhesive composition includes the copolymer in an amount of at least about 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, or 99, or greater, weight percent based on a total weight of the adhesive composition. In various nonlimiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[0054] In various embodiments, the additive is chosen from a tackifier, a plasticizer, filler particles, and combinations thereof. The additive may be a tackifier and/or a plasticizer. The additive may be filler particles. In various embodiments, the filler particles are chosen from, silica, cellulosic, polysaccharides, conductive fillers, metallic fibers, graphitic, carbon nanotubes, and combinations thereof. The tackifier, plasticizer, and/or filler particles may be any known in the art. These may be any known in the art and may be included in any amount as chosen by the skilled person.

[0055] The adhesive composition may be designed to be applied to any substrate. For example, the substrate may be human or animal skin. Alternatively, the substrate may be a medical device or implement. The substrate may be plastic, polymeric, fabric, nonwoven, paint, wood, metal, ceramic, etc.

[0056] The adhesive composition can be a pressure sensitive adhesive (also commonly referred to as a PSA). The term ‘pressure sensitive adhesive’ and the acronym ‘PSA’ are used interchangeably throughout the subject description.

[0057] As more specific examples of particular applications, pressure sensitive adhesives are frequently applied in the following applications: medical device skin adhesion, medical device assembly adhesion, adhesive tape, adhesive film, surgical drape adhesionh, electrically conductive adhesives, ostomy device sealing and adhesion, wound care dressings, IV dressings, external prosthesis fixation, and scar care therapies.

[0058] As a more specific example of one particular application, pressure sensitive adhesives are frequently applied in transdermal drug delivery systems. These systems typically include an active agent and the pressure sensitive adhesive. The active agent, for example a pharmaceutical drug, is typically utilized for controlled transdermal delivery or release to a substrate, such as the skin of a user of the system. The pressure sensitive adhesive functions to maintain contact between the system and the substrate for extended periods of time such that the active agent can be delivered to the substrate. Examples of such systems can be found in U.S. Pat. Nos. 3,731,683; 3,797,494; 4,031,894; and 4,336,243, the contents of which are expressly incorporated herein by reference in various non-limiting embodiments.

[0059] The adhesive composition of this disclosure can be used in a transdermal drug delivery system. The system includes an active agent and the adhesive composition of this disclosure functioning as, or in, a pressure sensitive adhesive. Such a system is structural and can be in many forms including, but not limited to, patches, fdms, multi-layer dressings, reservoir systems, and combinations thereof. Typically, the PSA allows for controlled delivery of the active agent to a substrate. The system may also include a backing layer for supporting the adhesive composition and/or a release liner for protecting the adhesive composition and/or the active agent prior to the controlled transdermal delivery of the active agent to the substrate. One typical application of the transdermal drug delivery system is to treat a user, or patient, with the active agent. As a result, the substrate is typically the skin of the user and, in this typical application, the user applies and wears the system on the skin.

[0060] The active agent is not particularly limited and can be any known to be suitable for transdermal delivery to a substrate. Suitable active agents include, but are not limited to, those active agents disclosed and described in U.S. Pat. No. 5,474,783 the disclosure of which is incorporated by reference herein in its entirety in various non-limiting embodiments. These active agents include, but are not limited to, cardioactive medications, androgenic steroids, estrogens, hormones, pregestational agents, drugs having an action on the central nervous system, nutritional agents, anti-inflammatory agents, antihistamines, respiratory agents, sympathomimetics, miotics, cholinergic agonists, antimuscarinic or muscarinic cholinergic blocking agents, mydriatics, psychic energizers, anti-infectives, dermatological agents, humoral agents, antispasmodics, antidepressant drugs, antidiabetic, anorectic drugs, anti-allergenics, tranquilizers, antipsychotics, decongestants, antipyretics, antimigraine agents, drugs for treating nausea and vomiting, anti-malarials, anti -ulcerative agents, peptides, drugs for Parkinson’s disease, drugs for spasticity, drugs for acute muscle spasms, anti-estrogen, anti-hormone agents, therapeutic agents, and combinations thereof.

[0061] In one embodiment, the active agent is a cardioactive medication such as organic nitrates such as nitroglycerin, isosorbide dinitrate and, isosorbide mononitrates, quinidine sulfate, procainamide, thiazides such as Bendroflumethiazide, chlorothiazide, andhydrochlorothyazide, nifedipine, nicardipine, adrenergic blocking agents, such as timolol, and propranolol, verapamil, diltiazem, captopril, clonidine and prazosin. [0062] In another embodiment, the active agent is an androgenic steroid, such as testosterone, methyltestosterone and fluoxymesterone.

[0063] In another embodiment, the active agent is an estrogen, such as, conjugated estrogens, esterified estrogens, quinestrol, estropipate, 17-P estradiol, 17-(3 estradiol valerate, equilin, mestranol, estrone, estriol, 17-P ethinyl estradiol, and di ethylstilbestrol.

[0064] In another embodiment, the active agent is a progestational agent, such as progesterone, 19-nor- progesterone, norethindrone, norethindrone acetate, melengestrol, chlormadinone, ethisterone, medroxyprogesterone acetate, hydroxyprogesterone caproate, ethynodiol diacetate, norethynodrel, 17-alpha-hydroxyprogesterone, dydrogesterone, dimethi sterone, ethinylestrenol, norgestrel, demegestone, promegestone, and megestrol acetate. [0065] In another embodiment, the active agent is a drug having an action on the central nervous system, for example sedatives, hyponotics, antianxiety agents, analgesics and anesthetics, such as chloral, buprenorphine, naloxone, haloperidol, fluphenazine, pentobarbital, phenobarbital, secobarbital, codeine, lidocaine, tetracaine, dyclonine, dibucaine, cocaine, procaine, mepivacaine, bupivacaine, etidocaine, prilocaine, benzocaine, fentanyl, and nicotine. [0066] In another embodiment, the active agent is a nutritional agent, such as vitamins (e.g. niacinamide), essential amino acids and essential fats.

[0067] In another embodiment, the active agent is an anti-inflammatory agent, such as hydrocortisone, cortisone, dexamethasone, fluocinolone, triamcinolone, medrysone, prednisolone, flurandrenolide, prednisone, halcinonide, methylprednisolone, fludrocortisone, corticosterone, paramethasone, betamethasone, ibuprofen, naproxen, fenoprofen, fenbufen, flurbiprofen, acetaminophen, indoprofen, ketoprofen, suprofen, indomethacin, piroxicam, aspirin, salicylic acid, diflunisal, methyl salicylate, phenylbutazone, sulindac, mefenamic acid, meclofenamate sodium, naproxen, and the like.

[0068] In another embodiment, the active agent is an external analgesic, such as camphor, menthol, capsicum extract, frankincense, green tea, juniper tea, and caffeine. Antihistamines, such as diphenhydramine, dimenhydrinate, perphenazine, triprolidine, pyrilamine, chlorcyclizine, promethazine, carbinoxamine, tripelennamine, brompheniramine, hydroxyzine, cyclizine, meclizine, terfenadine, and chlorpheniramine can also be used.

[0069] In another embodiment, the active agent is a respiratory agent, such as theophylline and Beta-adrenergic agonists such as albuterol, terbutaline, metaproterenol, ritodrine, carbuterol, fenoterol, quinterenol, rimiterol, solmefamol, soterenol, and tretoquinol. Sympathomimetics such as dopamine, norepinephrine, phenylpropanolamine, phenylephrine, pseudoephedrine, amphetamine, propylhexedrine and epinephrine can also be used. Miotics such as pilocarpine, and the like can be used. Cholinergic agonists, such as choline, acetylcholine, methacholine, carbachol, bethanechol, pilocarpine, muscarine, and arecoline can also be used.

[0070] In another embodiment, the active agent is an antimuscarinic or muscarinic cholinergic blocking agent, such as atropine, scopolamine, homatropine, methscopolamine, homatropine methylbromide, methantheline, cyclopentolate, tropicamide, propantheline, anisotropine, dicyclomine, and eucatropine.

[0071] In another embodiment, the active agent is a mydriatic, such as atropine, cyclopentolate, homatropine, scopolamine, tropicamide, eucatropine and hydroxyamphetamine.

[0072] In another embodiment, the active agent is a psychiceneigizer, such as 3-(2- aminopropy)indole, 3-(2- aminobutyl)indole, and the like.

[0073] In another embodiment, the active agent is an anti-infective, such as antibiotics, including penicillin, tetracycline, chloramphenicol, sulfacetamide, sulfadiazine, sulfamethoxazole and sulfisoxazole. antivirals, including idoxuridine. Antibacterials, such as erythromycin and clarithromycin, anti-fungals, such as ketoconazole, and other anti-infectives including nitrofurazone, cyclopirox, terbafine, witch hazel, and the like can also be used.

[0074] In another embodiment, the active agent is a dermatological agent, such as retinoids. Vitamins C and E. benzoyl peroxide (BPO) (also commonly referred to as dibenzoyl peroxide) and dapsone can also be used.

[0075] In another embodiment, the active agent is a humoral agent, such as the prostaglandins, natural and synthetic, for example PGE1, PGE2-alpha and PGF 2-alpha, and the PGE1 analog misoprostol.

[0076] In another embodiment, the active agent is an antispasmodic, such as atropine, methantheline, papaverine, cinnamedrine, and methscopolamine.

[0077] In another embodiment, the active agent is an antidepressant drug, such as paroxetine, phenelzine, tranylcypromine, imipramine, amitriptyline, trimipramine, doxepin, desipramine, nortriptyline, protriptyline, amoxapine, maprotiline, and trazodone. [0078] In another embodiment, the active agent is an anti-diabetic, such as insulin, or an anticancer drug such as tamoxifen and methotrexate.

[0079] In another embodiment, the active agent is an anorectic drug, such as, dextroamphetamine, methamphetamine, phenylpropanolamine, fenfluramine, diethylpropion, mazindol, and phentermine.

[0080] In another embodiment, the active agent is an anti-allergenic, such as antazoline, methapyrilene, chlorpheniramine, pyrilamine and pheniramine.

[0081] In another embodiment, the active agent is a tranquilizer, such as reserpine, chlorpromazine, and antianxiety benzodiazepines such as alprazolam, chlordiazepoxide, clorazeptate, halazepam, oxazepam, prazepam, clonazepam, flurazepam, triazolam, lorazepam and diazepam.

[0082] In another embodiment, the active agent is an antipsychotic, such as thiopropazate, chlorpromazine, triflupromazine, mesoridazine, piperacetazine, thioridazine, acetophenazine, fluphenazine, perphenazine, trifluoperazine, chlorprothixene, thiothixene, haloperidol, bromperidol, loxapine, and molindone.

[0083] In another embodiment, the active agent is a decongestant, such as phenylephrine, ephedrine, naphazoline, tetrahydrozoline.

[0084] In another embodiment, the active agent is an antipyretic, such as aspirin, salicylamide, and the like.

[0085] In another embodiment, the active agent is an antimigrane agent, such as dihydroergotamine and pizotyline.

[0086] In another embodiment, the active agent is a drug for treating nausea and vomiting, such as chlorpromazine, perphenazine, prochlorperazine, promethazine, triethylperazine, triflupromazine, and trimeprazine.

[0087] In another embodiment, the active agent is an anti-malarial, such as the 4- aminoquinolines, alphaminoquinolines, chloroquine, and pyrimethamine.

[0088] In another embodiment, the active agent is an anti-ulcerative agent, such as misoprostol, omeprazole, and enprostil.

[0089] In another embodiment, the active agent is a peptide, such as growth releasing factor. [0090] In another embodiment, the active agent is a drug for Parkinson’s disease, spasticity, and acute muscle spasms such as levodopa, carbidopa, amantadine, apomorphine, bromocriptine, selegiline (deprenyl), trihexyphenidyl hydrochloride, benztropine mesylate, procyclidine hydrochloride, baclofen, diazepam, and dantrolene. Anti-estrogen or hormone agents, such as tamoxifen or human chorionic gonadotropin can also be used.

[0091] Other examples of suitable active agents fare described on pages 149-217 of Yie Chien’s treatise entitled “Novel Drug Delivery Systems” which is Volume 14 of Drugs and the Pharmaceutical Sciences, Marcel Dekker, Inc, New York, N.Y. 10016 (1982)), which is expressly incorporated herein by reference in various non-limiting embodiments

[0092] The active agent can be present in the system in different forms, depending on which form yields optimum delivery characteristic, such as the release rate and the total amount released as described below. For example, in the case of drugs, the drug can be in its free base or acid form, or in the form of salts, esters, or any other pharmacologically acceptable derivatives, or even as components of molecular complexes.

[0093] The active agent is most typically disposed in the adhesive composition. However, it is also to be understood that the active agent and the adhesive composition may coexist in the system in discrete layers. That is, in certain embodiments, the active agent is not disposed, or directly incorporated, into the adhesive composition.

[0094] The transdermal drug delivery system can also include other agents known to accelerate the delivery of the active agent through the skin or other substrate. These other agents are also known as skin-penetration or permeation enhancers, accelerants, adjuvants, and sorption promoters, and are collectively referred herein simply as “enhancers”. These enhancers include those with diverse mechanisms of action including those which have the function of improving the solubility and diffusibility of the active agent and those which improve percutaneous absorption, for example, by changing the ability of the stratum comeum to retain moisture, softening the skin, improving the skin’s permeability, acting as penetration assistants or hair-follicle openers or changing the state of the skin including the boundary layer. Some of these enhancers have more than one mechanism of action, but generally serve to enhance the delivery of the active agent to the substrate.

[0095] Some non-limiting examples of enhancers are polyhydric alcohols such as dipropylene glycol, propylene glycol, and polyethylene glycol which enhance solubility of the active agent, oils such as olive oil, squalene, and lanolin; fatty ethers such as cetyl ether and oleyl ether; fatty acid esters such as isopropyl myristate which enhance diffusibility of the active agent; urea and urea derivatives such as allantoin which affect the ability of keratin to retain moisture; polar solvents such as dimethyldecylphosphoxide, methyl octyl sulfoxide, dimethyllaurylamide, dodecylpyrrolidone, isosorbitol, dimethylacetonide, dimethylsulfoxide, decylmethylsulfoxide, and dimethylformamide which affect keratin permeability; salicylic acid which softens the keratin; amino acids which are penetration assistants; benzyl nicotinate which is a hair follicle opener; and higher molecular weight aliphatic surfactants such as lauryl sulfate salts which change the surface state of the substrate, e.g. skin, and the active agents administered. Other agents include oleic and linoleic acids, ascorbic acid, panthenol, butylated hydroxytoluene, tocopherol, tocopheryl acetate, tocopheryl linoleate, propyl oleate, and isopropyl palmitate.

[0096] In various embodiments, a plasticizer or tackifying agent may be incorporated into the system, typically into the adhesive composition, to improve the adhesive characteristics. A tackifying agent is particularly useful in those embodiments in which the active agent does not plasticize the copolymer. Suitable tackifying agents include those known in the art including: (1) aliphatic hydrocarbons; (2) mixed aliphatic and aromatic hydrocarbons; (3) aromatic hydrocarbons; (4) substituted aromatic hydrocarbons; (5) hydrogenated esters; (6) polyterpenes; and (7) hydrogenated wood rosins. The tackifying agent employed is typically compatible with the other components in the adhesive composition. Examples of suitable tackifying agents are silicone fluids (e.g., Liveo™ Q7-9120 Silicone Fluid, available from DuPont™ Healthcare, Midland, Mich ), silicone resins of the general formula RixR2ySiOz where Ri is alkyl, phenyl, vinyl groups for example, R2 is OH, H, alkoxy, trimethyl siloxy groups for example , or mineral oil. Silicone fluids and silicone resins are useful for blends. In other embodiments, mineral oil is a useful tackifying agent.

[0097] Notably some active agents, such as vasodilator nitroglycerin, function as plasticizers because they are soluble to a certain degree in the components of the PSA. For active agents which are not readily soluble, a co-solvent for the active agent and other components can be added. Co-solvents, such as lecithin, retinol derivatives, tocopherol, dipropylene glycol, triacetin, propylene glycol, saturated and unsaturated fatty acids, mineral oil, silicone fluid, alcohols, butyl benzyl phthalate, and the like can be used herein.

[0098] Independent of, or in conjunction with, the tackifying agent, the adhesive composition maintains contact between the system and the substrate. In other embodiments, the adhesive composition possesses sufficient tack and cohesive strength so that it can be adhered with mild pressure and also removed and the adhered again (to the same or another).

[0099] The adhesive composition may also include a variety of other formulation additives that are known in the art. These additives are typically included in small amounts to influence a select physical property or to improve a certain performance feature. Examples of these additives include, but are not limited to, fillers, such as silicas or calcium carbonate, aerogels, pigments, antioxidant agents, defoaming agents, wetting agents, and viscosity adjusting agents. In various embodiments, the adhesive composition further includes a tackifier and/or a plasticizer, and/or filler particles chosen from silica, cellulosic, metal oxide particles, metallic nanorods, metallic nanowires, graphitic, carbon nanotubes, and combinations thereof. These additives are applicable whether the adhesive composition is being used in a transdermal drug delivery system or not.

[00100] Other applications provided herein include, but are not limited to, tapes, labels, notes, bandages, transdermal drug delivery systems (e.g. patches), lipstick, hair spray, hair fixatives, and other cosmetic products, transfer adhesives, laminating adhesives, surface priming, and vibration damping.

Physical Properties

[00101] The copolymer and adhesive composition are not particularly limited relative to physical properties. In various embodiments, the copolymer and/or adhesive composition is free of, or includes less than 0.5, 0.4, 0.3, 0.2, 0.1, or 0.05, weight percent of, urethane linkages. In various non-limiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein. In various embodiments, it is desirable to have few to no urethane linkages.

[00102] In other embodiments, the copolymer and/or adhesive composition has a cohesive strength (G’) of at least about 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 etc. N/cm² as determined by frequency sweep rheology tests, e.g. using ASTM D7605-11 and measured at a rotational frequency of 100 rad/s and temperature of 30°C. In various embodiments, the copolymer and/or adhesive composition has a cohesive strength of from about 1 to 50, about 5 to about 45, about 10 to about 40, about 15 to about 35, about 20 to about 30, or about 20 to about 25, N/cm². Cohesive strength is generally desirable such that the adhesive composition does not tear apart as it is being removed from a substrate. In various non-limiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[00103] In other embodiments, the copolymer and/or adhesive composition has an adhesive peel strength of at least 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, etc. N/cm as determined by peel adhesion testing on a polycarbonate substrate. In various embodiments, the copolymer and/or adhesive composition has an adhesive peel strength of from about 0.1 to 40, about 1 to about 10, about 2 to about 9, about 3 to about 8, about 4 to about 7, about 5 to about 6, about 0.1 to about 1, about 0.2 to about 0.9, about 0.3 to about 0.8, about 0.4 to about 0.7, about 0.5 to about 0.6, about 1 to about 40, about 5 to about 35, about 10 to about 30, about 15 to about 25, or about 20 to about 25, N/cm. Adhesive peel strength is generally desirable such that the adhesive composition does not peel away from the substrate before an appropriate time or without an appropriate or desirable amount of force. In various non-limiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

[00104] Typically, peel adhesion in N (newtons) is measured using Tensile Testing equipment (e.g. Instron). A sample is prepared by heating composition, coating an appropriate substrate therewith, and pressing to the desired thickness. The coated substrate is then cut in 2.5 cm strips (1 inch), and a polycarbonate film is laminated to the surface. Test parameters include: 180° peel release test, test speed = 10.0 mm/s, distance = 90.0 mm. Each sample was run in triplicate and the average force (N) was reported. Any observed characteristics are then noted.

[00105] In other embodiments, the copolymer and/or adhesive composition has a tack value of from about 1.0-10.0 gf as determined using ASTM D2979-16. Tack strength is typically desirable because it enables an adhesive to form a bond of measurable strength (bond strength) immediately after the adhesive and the substrate are brought into contact under low pressure. In various non-limiting embodiments, all values and ranges thereof, both whole and fractional, including and between those set forth above, are hereby expressly contemplated for use herein.

Additional Embodiments

[00106] This disclosure further provides a silicone-polyester copolymer including: a plurality of first segments, each first segment derived from a branched silicone diol of the formula:

wherein:

R¹, R², and R³ are each independently chosen from C1-C4 aliphatic groups or - OSiRⁿ3 wherein R¹¹ is a C1-C4 aliphatic group, provided that at least two of R¹, R², or R³ are -OSiR¹^; x is from 1 to 4; y is from 1 to 3;

R⁴ is H or a C1-C4 alkyl group; and

R⁵ and R⁶ are each independently chosen from C1-C4 aliphatic groups.

[00107] Typically, the terminology “first segment” describes a repeating unit of the copolymer. Accordingly, the copolymer may have one or more repeating units having the structure as set forth above and/or may have one or more of the above units reacted such that they are part of the polymer and thus may be described as residues, moieties, or groups.

EXAMPLES

[00108] In the following Examples, unless otherwise noted, all parts and percentages are by weight.

Table 1. Abbreviations used herein.

[00109] A series of compositions are formed as follows:

[00110] All of the reaction components except for the catalyst and 1,4-butandiol are added to a reactor. The reactor is evacuated and backfilled with nitrogen three times. The reaction mass is heated to a jacket temperature of 160 °C with stirring at 60 RPM The n-butyl titanate catalyst is stirred at 50 °C for 2 hours in 1,4-butandiol. Then this catalyst solution is injected once the reactor reaches an internal temperature of 80 °C-120 °C. The jacket temperature is then raised to 210 °C for ~ 2.5 hours with concomitant distillation of methanol. Once butanediol begins to azeotrope with the methanol - corresponding to a drop in temperature at the bottom of the distillation column - the jacket temperature is raised to 240 °C, and the pressure in the reactor is reduced to ~ 80 torr-90 torr. After ~ 1 h, the jacket temperature is raised to 250 °C. After another hour, the jacket temperature is raised to 260 °C and the pressure is reduced to ~ 20 torr. The vacuum is raised over the next 2-6 hours until the pressure in the reactor is ~ 0.5 torr. The reaction is stirred at this temperature and pressure until the torque plateaus for ~ 30 minutes. At this time, the reactor is cooled to room temperature and jacketed with nitrogen. The resulting polymer is manually removed from the vessel.

Example 1 - Elastomeric Rubbery Solid

[00111] The following reactants are utilized:

DMT 230.87 g; BDO 182.09 g; silicone-polyether (Mw 1800) 322.24 g; Ethanox 330 3.25 g; n-butyl titanate catalyst 2.6 g

[00112] Without any branched silicone diol content, the resulting polymer is non-adhesive and only low molecular weights are achieved.

Example 2 - Elastomeric Rubbery Solid

[00113] The following reactants are utilized:

DMT 226.84 g; BDO 190.53 g; silicone-polyether (Mw 2900) 322.1 g; Ethanox 330 3.22 g; Irganox 1098 g; n-butyl titanate catalyst 2.58 g

[00114] Without any branched silicone diol content, the resulting polymer is non-adhesive and only low molecular weights are achieved.

Example 3 - Adhesive Thermoplastic Solid

[00115] The following reactants are utilized:

DMT 155.44 g; BDO 22.46 g; silicone-polyether (Mw 1800) 241.58 g; Ethanox 330 3.22 g; n- butyl titanate catalyst 2.58 g; branched silicone diol 241.58 g

[00116] This polymer exhibits good adhesion but, as shown in FIG. 1, the rheology exhibits lower than optimal cohesive strength, being softer and deforming more readily than desired for a pressure sensitive adhesive.

Example 4 - Adhesive Thermoplastic Solid

[001171 The following reactants are utilized:

DMT 75.639 g; BDO 27.21 g; silicone-polyether (Mw 1800) 179.526 g; Ethanox 330 0.9 g; n- butyl titanate catalyst 1.2 g; branched silicone diol 110.568 g

[00118] This polymer exhibits good adhesion combined with better cohesive strength than Example 3, as shown in FIG. 2, due to a more optimal content of branched silicone diol.

Example 5 -Slightly Tacky Elastomeric Solid

[00119] The following reactants are utilized:

DMT 100.852 g; BDO 36.28 g; silicone-polyether (Mw 1800) 239.368 g; Ethanox 330 1.2 g; n-butyl titanate catalyst 1.6 g; branched silicone diol 147.424 g

[00120] This Example includes a similar composition loaded into the reactor as Example 4. However, the reaction is stopped prematurely, incorporating less branched silicone diol in the final polymer and resulting in a more rubbery, less adhesive material. Rheology results are set forth in FIG. 3.

Example 6 - Tacky Elastomeric Solid

[00121] The following reactants are utilized:

DMT 101.608 g; BDO 36.552 g; silicone-polyether (Mw 1800) 217.384 g; Ethanox 330 1.2 g; n-butyl titanate catalyst 1.6 g; branched silicone diol 148.528 g; monohydroxy silicone 20.78 g [00122] This Example is similar to example 5 except that the reaction is stopped prematurely. Rheology results are set forth in FIG. 4.

Example 7 - Adhesive Thermoplastic Soft Solid

[00123] The following reactants are utilized:

DMT 73.792 g; BDO 26.544 g; silicone-polyether (Mw 1800) 282.164 g; Ethanox 330 1.2 g; n-butyl titanate catalyst 1.6 g; branched silicone diol 107.864 g

[00124] This example produces a polymer of lower cohesive strength than Example 4.

Example 8 - Tacky Elastomeric Solid

[00125] The following reactants are utilized:

DMT 139.728 g; BDO 50.268 g; EOPPG 377.334 g; Ethanox 330 1.8 g; n-butyl titanate catalyst 2.4 g; branched silicone diol 204.252 g [00126] This Example demonstrates that EOPPG at equivalent loading does not yield as soft of a polymer as silicone-polyethers.

Example 9

[00127] The following reactants are utilized:

DMT 134.814 g; BDO 90.552 g; EOPPG 364.056 g; Ethanox 330 1.8 g; n-butyl titanate catalyst 2.4 g; High MW Branched Silicone Diol 98.532 g.

[00128] In this example the higher molecular weight branched silicone diol did not react into polymer backbone, remaining as an immiscible oil.

Example 10 - Adhesive Thermoplastic Stretchy Solid

[00129] The following reactants are utilized:

DMT 87.38 g; BDO 16.93 g; EOPPG 235.97 g; Ethanox 330 1.2 g; n-butyl titanate catalyst 1.6 g; branched silicone diol 191.61 g

[00130] This reaction produces the adhesive thermoplastic stretchy solid that is capable of long elongation.

[00131] Polyester copolymer compositions often do not function well as pressure sensitive adhesives, not yielding the balance of adhesion with cohesive material strength needed. Importantly, compositions with appropriate contents of short-chain branched silicone diol content in proportion to other polymer units are found to give attractive performance as pressure sensitive adhesives.

[00132] More specifically, Examples 1-10 are evaluated to determine peel adhesion. The results are set forth below:

* High MW Branched Silicone Diol didn’t react into polymer backbone, remaining as an immiscible oil.

[00133] These results are unexpected over what is known in the art because it has been surprisingly discovered that polyester polymerizations utilizing branched silicone diols both enable the facile synthesis of higher molecular weight silicone containing co-polyesters and enhance the adhesive properties of these polymers allowing them to function as pressure sensitive adhesives.

[00134] In addition, Examples 3-6 were also analyzed via parallel plate rheology at 30°C to determine Storage Modulus and Loss Modulus, each as a function of angular frequency. The results are set forth as Figures 1-4.

[00135] Typically, peel adhesion in N (newtons) is measured using Tensile Testing equipment (e.g. Instron). A sample is prepared by heating composition, coating an appropriate substrate therewith, and pressing to the desired thickness. The coated substrate is then cut in 2.5 cm strips (1 inch), and a polycarbonate film is laminated to the surface. Test parameters include: 180° peel release test, test speed = 10.0 mm/s, distance = 90.0 mm. Each sample was run in triplicate and the average force (N) was reported. Any observed characteristics are then noted.

[00136] Parallel plate rheology is recorded on a TA Instruments Ares G2 at a sample measurement temperature of 30°C and following ASTM D7605-11. Cohesive strength correlates with values G’ and G” values measured in the rotational frequency range of 10 rad/s- 100 rad/s.

[00137] These rheology results show that, while utilization of branched silicone diol monomers enhances adhesion performance, the branched silicone diol monomers are polymerized in previously unknown and unexpected proportions to other co-polyester monomers to yield an adhesive material with sufficient cohesive strength as well as adhesion.

[00138] While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the present disclosure in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the present disclosure. It being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the present disclosure as set forth in the appended claims.

Claims

CLAIMS What is claimed is:

1. A silicone-polyester copolymer comprising the reaction product of: a branched silicone diol containing at least one branched silicone group; and a dicarboxylic acid; wherein the silicone-polyester copolymer has a molar ratio of units derived from the branched silicone diol to units derived from the dicarboxylic acid of at least about 0.05: 1; and wherein the silicone-polyester copolymer has a weight average molecular weight of at least about 25,000 Daltons.

2. The silicone-polyester copolymer of claim 1, wherein the silicone-polyester copolymer comprises a total of at least 2 units derived from the branched silicone diol and units derived from the dicarboxylic acid.

3. The silicone-polyester copolymer of any one of claims 1 or 2, wherein the branched silicone diol has a weight average molecular weight of from about 300 to about 1500 Daltons.

4. The silicone-polyester copolymer of any preceding claim, wherein the branched silicone diol has the formula:

wherein:

R¹, R², and R³ are each independently chosen from C1-C4 aliphatic groups or -OSiR' wherein R¹¹ is a C1-C4 aliphatic group, provided that at least two of R¹, R², or R³ are -OSiRⁿ3; x is from 1 to 4; y is from 1 to 3;

R⁴ is H or a C1-C4 alkyl group; and

R⁵ and R⁶ are each independently chosen from C1-C4 aliphatic groups.

5. The silicone-polyester copolymer of claim 4, wherein: two of R¹, R², or R³ are -OSiR' ; one of R¹, R², or R³ is methyl;

R¹¹ is methyl; x is 3; y is 1;

R⁴ is ethyl; and

R⁵ and R⁶ are methylene groups.

6. The silicone-polyester copolymer of any preceding claim, wherein the dicarboxylic acid is chosen from terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, phthalic acid or phthalic anhydride, cyclohexanedicarboxylic acid, biphenyl dicarboxylic acid, any of the series of C4-C10 aliphatic dicarboxylic acids, a spiroacetal diacid, or a combination thereof.

7. The silicone-polyester copolymer of claim 6 wherein the at least one dicarboxylic acid comprises an aromatic dicarboxylic acid chosen from one or more of terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid.

8. The silicone-polyester copolymer of any preceding claim, wherein the silicone- polyester copolymer has a molar ratio of units derived from the branched silicone diol to units derived from the dicarboxylic acid of from about 0.1 : 1 to 1 : 1.

9. The silicone-polyester copolymer of any preceding claim, wherein the silicone- polyester copolymer has a weight average molecular weight of from about 25,000 to about 500,000 Daltons.

10. The silicone-polyester copolymer of any preceding claim, wherein the reaction product is further defined as the reaction product of: the branched silicone diol containing the at least one branched silicone group; the dicarboxylic acid; and a dihydroxy-terminated polymeric diol different from the branched silicone diol; and/or an aliphatic diol having from 2 to 8 carbon atoms.

11. The silicone-polyester copolymer of any preceding claim, wherein the reaction product is further defined as the reaction product of: the branched silicone diol containing the at least one branched silicone group; the dicarboxylic acid; and a dihydroxy-terminated polymeric diol different from the branched silicone diol, wherein the dihydroxy-terminated polymeric diol is chosen from poly(alkylene oxide)diols, linear aliphatic polyesters, linear aliphatic polycarbonates, linear polyether polysilicone diols, branched polyether polysilicone diols, and mixtures thereof.

12. The silicone-polyester copolymer of claim 11, wherein the dihydroxy-terminated polymeric diol comprises a linear polyether polysilicone diol having a weight average molecular weight of at least 800 Daltons and the polysilicone moiety is at least 30 weight percent of the linear poly ether poly silicone diol.

13. The silicone-polyester copolymer of claim 12 having the formula:

wherein: c is from about 1 to about 30; d is from about 0 to about 20; and g is from about 3 to about 50

R¹² and R¹³ are each independently chosen from C1-C4 aliphatic groups.

14. The silicone-polyester copolymer of any preceding claim, wherein the reaction product is further defined as the reaction product of: the branched silicone diol containing the at least one branched silicone group; the dicarboxylic acid; and an aliphatic diol chosen from 1,2-ethanediol; 1,3-propanediol; 1,4-butanediol; 1,5- pentanediol; 1,6-hexanediol; 2-methyl-l,3-propanediol; 2,2-dimethy-l,3- propanediol; 1,2- dihydroxy cyclohexane; 1,3-dihydroxy cyclohexane; 1,4-dihydroxy cyclohexane; 1,4- butenediol; diethyleneglycol; and mixtures thereof.

15. The silicone-polyester copolymer of claim 14, having a molar ratio of units derived from the aliphatic diol to units derived from the dicarboxylic acid of from about 0.1 : 1 to about 0.8:1.

16. The silicone-polyester copolymer of claim 1, wherein the reaction product is further defined as the reaction product of: the branched silicone diol containing the at least one branched silicone group; the dicarboxylic acid; and a monohydroxyl containing compound.

17. The silicone-polyester copolymer of any preceding claim that is free of urethane linkages.

18. The silicone-polyester copolymer of any preceding claim, wherein the copolymer has a cohesive strength (G’) of at least about 0.01 MPa as determined by ASTM D7605-11 and measured at a rotational frequency of 100 rad/s and temperature of 30°C and an adhesive peel strength of at least 0.4 N/cm as determined by peel adhesion testing on polycarbonate substrates.

19. The adhesive composition of claim 18, comprising the silicone-polyester copolymer is present in an amount of at least about 30 weight % based on a total weight of the adhesive composition.

20. A silicone-polyester copolymer comprising: a plurality of first segments, each first segment derived from a branched silicone diol of the formula:

wherein:

R¹, R², and R³ are each independently chosen from C1-C4 aliphatic groups or -OSiR^U3 wherein R¹¹ is a C1-C4 aliphatic group, provided that at least two of R¹, R², or R³ are -OSiR’ ; x is from 1 to 4; y is from 1 to 3;

R⁴ is H or a C1-C4 alkyl group; and

R⁵ and R⁶ are each independently chosen from C1-C4 aliphatic groups.