85693-WO-PCT/DOW 85693 WO IONOMERS OF ETHYLENE ACID COPOLYMERS WITH IMPROVED ULTRAVIOLET STABILITY CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application Serial No. 63/594,481 filed October 31, 2023, the contents of which are incorporated in their entirety herein. TECHNICAL FIELD [0002] The present disclosure generally relates to ionomers of ethylene acid copolymers, and specifically relates to ionomers of ethylene acid copolymers that provide improved ultraviolet (UV) stability. BACKGROUND [0003] Ionomers are commonly used materials in various applications, because they have higher tensile strength, greater clarity, better abrasion resistance and higher stiffness than the precursor acid copolymers. For example, the ionomers of ethylene acid copolymers have found utility in many applications, such as food packaging, foamed parts, injection molded parts (e.g., cosmetic containers), and golf ball components. SUMMARY [0004] Although ionomers may be utilized in many applications, many ionomers have poor stability in the presence of ultraviolet (UV) light. This poor stability is especially an issue for ionomers exposed to sunlight in outdoor applications, which may include ionomers used to build decks and other structures, as well as ionomers used in outdoor furniture. Poor UV stability may result in degradation, loss of mechanical properties, and discoloration of articles that include the ionomer. Traditional approaches to improving the UV stability of ionomers include using conventional UV stabilizers intended to protect polyethylene. Unfortunately, this approach is largely ineffective for ionomers, because the acid functional groups of the ionomers degrade or
85693-WO-PCT/DOW 85693 WO interact with the conventional UV stabilizers, which compromises the effectiveness of UV stabilizers. In some scenarios, the interaction between UV stabilizers and acid functional groups of the ionomer even deteriorates the UV stability of the ionomer. Therefore, ionomers with improved UV resistance are needed. [0005] Embodiments of the present disclosure address this need for ionomers with improved UV resistance by utilizing a triazine-based UV absorber and a hindered amine light stabilizer. [0006] According to one embodiment, a composition includes an ionomer, the ionomer including an ethylene acid copolymer including the polymerized reaction product of from 60 wt.% to 99 wt.% ethylene, and from 1 wt.% to 6 wt.% carboxylic acid monomers, wherein the ethylene acid copolymer is at least partially neutralized with metal cations, the metal cations including zinc or sodium, provided that when the metal cations include zinc, up to 75 mol.% of the carboxylic acid monomers are neutralized, a triazine-based UV absorber and a hindered amine light stabilizer. [0007] These and other features, aspects, and advantages will become better understood with reference to the following description and the appended claims. [0008] Additional features and advantages of the examples described herein will be set forth in the detailed description that follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the examples described herein, including the detailed description that follows, and the claims. [0009] It is to be understood that both the foregoing general description and the following detailed description describe various examples and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. DETAILED DESCRIPTION [0010] Specific embodiments of the present application will now be described. These embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the subject matter to those skilled in the art.
85693-WO-PCT/DOW 85693 WO [0011] The term “polymer” refers to a polymeric compound prepared by polymerizing monomers, whether of a same or a different type. The generic term polymer thus embraces the term “homopolymer,” which usually refers to a polymer prepared from only one type of monomer as well as “copolymer,” which refers to a polymer prepared from two or more different monomers. The term “interpolymer,” as used herein, refers to a polymer prepared by the polymerization of at least two different types of monomers. The generic term interpolymer thus includes a copolymer or polymer prepared from more than two different types of monomers, such as terpolymers. [0012] “Ethylene polymer” shall mean polymers comprising greater than 50% by weight of units derived from ethylene monomer. This includes ethylene homopolymers or copolymers (meaning units derived from two or more comonomers). Common forms of ethylene polymers known in the art include, but are not limited to, Low Density Polyethylene (LDPE); Linear Low Density Polyethylene (LLDPE); Ultra Low Density Polyethylene (ULDPE); Very Low Density Polyethylene (VLDPE); single-site catalyzed Linear Low Density Polyethylene, including both linear and substantially linear low density resins (m- LLDPE); Medium Density Polyethylene (MDPE); and High Density Polyethylene (HDPE). [0013] “Recycled polymer” refers to polymers, which were incorporated into products and subsequently re-melted to form a recycled polymer. The term “recycled polymer” refers to mechanically recycled polymers, where the polymer is melted and reincorporated into a new product. “Recycled polymer” does not include chemically recycled polymers, where the polymer is broken down into constituent monomers and incorporated into a new virgin polymer. The term “recycled polymer” embraces both pre-consumer recycled polymer and post-consumer recycled polymer. Recycled polymers are defined in ISO 140217.8.1.1. [0014] The terms “pre-consumer recycled polymer” and “post-industrial recycled polymer” refer to polymers, including blends of polymers, recovered from pre-consumer material, as defined by ISO-14021. The generic term pre-consumer recycled polymer thus includes blends of polymers recovered from materials diverted from the waste stream during a manufacturing process. The generic term pre-consumer recycled polymer excludes the reutilization of materials, such as rework, regrind, or scrap, generated in a process and capable of being reclaimed within
85693-WO-PCT/DOW 85693 WO the same process that generated it. Pre-consumer recycled polymer is defined in ISO 14021 7.8.1.1. [0015] The term “post-consumer recycled” (or “PCR”), as used herein, refers to a polymeric material that includes materials previously used in a consumer or industry application (i.e., pre- consumer recycled polymer and post-industrial recycled polymer). PCR is typically collected from recycling programs and recycling plants. The PCR ethylene-based polymer may include one or more of ethylene-based polymers, such as LDPE, LLDPE, HDPE, or polyethylene. The PCR may include one or more contaminants. The contaminants may be the result of the polymeric material’s use prior to being repurposed for reuse. For example, contaminants may include paper, ink, food residue, or other recycled materials in addition to the polymer, which may result from the recycling process. PCR is distinct from virgin polymeric material. A virgin polymeric material (such as a virgin polyethylene resin) does not include materials previously used in a consumer or industry application. Virgin polymeric material has not undergone, or otherwise has not been subject to, a heat process or a molding process, after the initial polymer manufacturing process. The physical, chemical, and flow properties of PCR resins differ when compared to virgin polymeric resin, which in turn can present challenges to incorporating PCR into formulations for commercial use. Post-consumer resin is defined in ISO 140217.8.1.1. [0016] “Ethylene acid copolymer” is a polymerized reaction product of ethylene and one or more unsaturated carboxylic acids. [0017] The term "hindered amine light stabilizer" or “HALS” refers to sterically hindered amines of the class of compounds typically represented by 2,2,6,6 tetraalkyl piperidines. [0018] Reference will now be made in detail to examples of compositions including an ionomer, the ionomer including an ethylene acid copolymer including the polymerized reaction product of from 60 wt.% to 99 wt.% ethylene, and from 1 wt.% to 6 wt.% carboxylic acid monomers, wherein the ethylene acid copolymer is at least partially neutralized with metal cations, the metal cations including zinc or sodium, provided that when the metal cations include zinc, up to 75 mol.% of the carboxylic acid monomers are neutralized. The composition also includes a triazine-based UV absorber and a hindered amine light stabilizer.
85693-WO-PCT/DOW 85693 WO [0019] The composition includes an ionomer. The composition may include from 1 wt.% to 99 wt.% ionomer. In some examples, the composition may include from 1 wt.% to 99 wt.%, from 10 wt.% to 99 wt.%, from 20 wt.% to 99 wt.%, from 30 wt.% to 99 wt.%, or from 40 wt.% to 99 wt.% ionomer. [0020] The ionomer includes an ethylene acid copolymer. The ethylene acid copolymer includes or is derived from 60 weight percent (wt.%) to 99 wt.% ethylene monomer. In some examples, the polymerized reaction product includes from 60 wt.% to 99 wt.% ethylene, from 60 wt.% to 95 wt.% ethylene, from 60 wt.% to 90 wt.% ethylene, 70 wt.% to 99 wt.% ethylene, from 70 wt.% to 95 wt.% ethylene, from 70 wt.% to 90 wt.% ethylene, 80 wt.% to 99 wt.% ethylene, from 80 wt.% to 95 wt.% ethylene, from 80 wt.% to 90 wt.% ethylene, or from 94 wt.% to 99 wt.% ethylene. [0021] The ethylene acid copolymer includes from 1 wt.% to 6 wt.% carboxylic acid monomers. The carboxylic acid monomers can be, for example, acrylic acid, methacrylic acid, or combinations thereof. In some examples, ethylene acid copolymer includes from 1 wt.% to 6 wt.% carboxylic acid monomers, from 1 wt.% to 5 wt.% carboxylic acid monomers, from 2 wt.% to 6 wt.% carboxylic acid monomers, from 2 wt.% to 5 wt.% carboxylic acid monomers, from 4 wt.% to 6 wt.% carboxylic acid monomers, from 4 wt.% to 5 wt.% carboxylic acid monomers, or from 3 wt.% to 4 wt.% carboxylic acid monomers. [0022] Without being limited by theory, it is believed that having less than 6 wt.% carboxylic acid monomers ensures that the ionomer, the resulting composition, and articles made therefrom have desirable properties, including scratch and/or grease resistance. Additionally, it is believed that compositions with higher weight percentages of carboxylic acid monomers may cause degradation of or interaction with UV stabilizers, thus decreasing the efficacy of the UV stabilizer. [0023] The ethylene acid copolymer can be prepared by standard free-radical copolymerization methods, using high pressure, operating in a continuous manner. Monomers are fed into the reaction mixture in a proportion which relates to the monomer’s activity, and the amount desired to be incorporated. In this way, uniform, near-random distribution of monomer units along the chain is achieved. Unreacted monomers may be recycled. The ethylene acid copolymer may be polymerized according to processes disclosed in U.S. Pat. Nos. 3,404,134; 5,028,674; 6,500,888;
85693-WO-PCT/DOW 85693 WO and 6,518,365. In some embodiments, blends of two or more ethylene acid copolymers may be used, provided that the aggregate components and properties of the blend fall within the limits described above for the ethylene acid copolymers. [0024] As noted above, the ethylene acid copolymer is at least partially neutralized with metal cations (to form an ionomer). In some examples, the metal cations include sodium. In examples where the metal cations include sodium, from 40 mol.% to 100 mol.% of the carboxylic acid monomers are neutralized with a sodium cation. In examples where the metal cations include sodium, from 40 mol.% to 100 mol.%, from 50 mol.% to 100 mol.%, from 60 mol.% to 100 mol.%, from 70 mol.% to 100 mol.%, from 80 mol.% to 100 mol.%, from 90 mol.% to 100 mol.%, 40 mol.% to 90 mol.%, from 50 mol.% to 90 mol.%, from 60 mol.% to 90 mol.%, from 70 mol.% to 90 mol.%, from 80 mol.% to 90 mol.%, 40 mol.% to 80 mol.%, from 50 mol.% to 80 mol.%, from 60 mol.% to 80 mol.%, from 70 mol.% to 80 mol.%, 40 mol.% to 70 mol.%, from 50 mol.% to 70 mol.%, from 60 mol.% to 70 mol.%, 40 mol.% to 60 mol.%, from 50 mol.% to 60 mol.%, or from 40 mol.% to 50 mol.% of the carboxylic acid monomers are neutralized with a sodium cation. [0025] In some examples, the metal cations include zinc. When the metal cations include zinc, up to 75 mol.% of the carboxylic acid monomers are neutralized. In examples where the metal cations include zinc, from 40 mol.% to 75 mol.%, of the carboxylic acid monomers are neutralized with a zinc cation. In examples where the metal cations include zinc, from 40 mol.% to 75 mol.%, 45 mol.% to 75 mol.%, 50 mol.% to 75 mol.%, 55 mol.% to 75 mol.%, 60 mol.% to 75 mol.%, 65 mol.% to 75 mol.%, 70 mol.% to 75 mol.%, 40 mol.% to 70 mol.%, 45 mol.% to 70 mol.%, 50 mol.% to 70 mol.%, 55 mol.% to 70 mol.%, 60 mol.% to 70 mol.%, 65 mol.% to 70 mol.%, 40 mol.% to 65 mol.%, 45 mol.% to 65 mol.%, 50 mol.% to 65 mol.%, 55 mol.% to 65 mol.%, 60 mol.% to 65 mol.%, 40 mol.% to 60 mol.%, 45 mol.% to 60 mol.%, 50 mol.% to 60 mol.%, 55 mol.% to 60 mol.%, 40 mol.% to 55 mol.%, 45 mol.% to 55 mol.%, 50 mol.% to 55 mol.%, 40 mol.% to 50 mol.%, 45 mol.% to 50 mol.%, or 40 mol.% to 45 mol.% of the carboxylic acid monomers are neutralized with a zinc cation. [0026] The composition further includes a triazine-based UV absorber. In one embodiment, the triazine UV absorber may comprise a 1,3,5,-triazine, 2,4,6-triphenyl with at least one phenyl
85693-WO-PCT/DOW 85693 WO group containing an hydroxyl substituent in the ortho position and one or more substituents selected from hydroxyl, alkyl, or alkoxyl, at one or more positions on the phenyl. In some examples, the composition includes from 0.01 weight percent (wt.%) to 2.00 wt.% UV stabilizer. In some examples, the composition includes from 0.01 weight percent (wt.%) to 2.00 wt.%, from 0.05 wt.% to 2.00 wt.%, from 0.10 wt.% to 2.00 wt.%, from 0.10 wt.% to 1.50 wt.%, or from 0.10 wt.% to 1.00 wt.%, UV stabilizer. [0027] The composition further includes a hindered amine light stabilizer. Various hindered amine light stabilizers are considered suitable. In some embodiments, these hindered amine light stabilizers may include heterocyclic amine moieties, such as piperidine. In some examples, the composition includes from 0.01 weight percent wt.% to 2.00 wt.% hindered amine light stabilizer. In some examples, the composition includes from 0.01 wt.% to 2.00 wt.%, from 0.05 wt.% to 2.00 wt.%, from 0.10 wt.% to 2.00 wt.%, from 0.50 wt.% to 2.00 wt.%, or from 0.50 wt.% to 1.50 wt.%, hindered amine light stabilizer. Examples of appropriate hindered amine light stabilizer compositions include CYASORB UV-3346 (C3346), which is a commercial hindered amine light stabilizer commercially available from Solvay USA Inc, Cincinnati, OH. [0028] The composition has a melt index (I2) from 0.1 to 30 g/10 minutes as measured according to ASTM D1238 Procedure A (190 °C, 2.16 kg). Unless otherwise stated, melt index was measured in grams per 10 minutes (g/10 minutes). In some examples, the ionomer has a melt flow from 0.1 to 30 g/10 minutes, from 0.2 to 15 g/10 minutes, or from 0.3 to 5 g/10 minutes. [0029] If the composition has a melt index (I2) below 0.1 g/10 minutes, the ionomer may not have sufficient melt flow for processability. Conversely, if the ionomer has a melt flow above 30.0 g/10 minutes, it may be too difficult to shape and mold the ionomer and the physical properties such as tensile strength, elongation at break, and scratch resistance would decline. [0030] In some examples, the composition may further include polyethylene, nylon, ethylene vinyl alcohol (EVOH), or combinations thereof. In one or more examples, the polyethylene, nylon, EVOH, or combinations thereof may include postconsumer recycled polyethylene, nylon, EVOH, or combinations thereof. In one or more examples the polyethylene, nylon, EVOH, or combinations thereof may include industrial recycled polyethylene, nylon, EVOH, or combinations thereof.
85693-WO-PCT/DOW 85693 WO [0031] The composition can additionally include small amounts of additives including plasticizers, stabilizers including viscosity stabilizers, hydrolytic stabilizers, primary and secondary antioxidants, anti-static agents, dyes, pigments or other coloring agents, inorganic fillers, fire-retardants, lubricants, reinforcing agents such as glass fiber and flakes, synthetic (for example, aramid) fiber or pulp, foaming or blowing agents, processing aids, slip additives, antiblock agents such as silica or talc, release agents, tackifying resins, or combinations of two or more thereof. Inorganic fillers, such as calcium carbonate, and the like can also be incorporated into the blend. These additives may be present in the blends in quantities ranging from 0.01 to 40 wt%, 0.01 to 25 wt%, 0.01 to 15 wt%, 0.01 to 10 wt%, or 0.01 to 5 wt%. The incorporation of the additives can be carried out by any known process such as, for example, by dry blending, by extruding a mixture of the various constituents, by the conventional masterbatch technique, or the like. [0032] Optionally, the composition may include additional ethylene-based polymers, such as HDPE. In one or more embodiments, the composition may include 20 to 60 wt.% HDPE, or from 40 to 60 wt.% HDPE. [0033] According to various examples, the composition may be used in various articles. These may include foams, sheets, films, laminates, or other articles produced through sheet or profile extrusion processes. [0034] In some examples, articles comprising the composition exhibit an elongation retention higher than 85% after 115 hours Super UV aging as explained in detail below. In examples wherein the carboxylic acid monomers are neutralized with a sodium cation, articles comprising the composition exhibits a color index change less than 5.0 after 270 hours Super UV aging. TEST METHODS [0035] Melt Index (I
2) [0036] Melt index (I
2) was measured in accordance with ASTM D-1238, Procedure B (condition 190°C/2.16 kg), the entirety of which is hereby incorporated by reference, and reported in grams eluted per 10 minutes (g/10 min).
85693-WO-PCT/DOW 85693 WO [0037] Super UV Aging [0038] Elongation retention was measured after 115 hours Super UV aging. A Super UV Tester, commercially available from EYE Applied-Optix was used. The Super UV Tester came equipped with a proprietary metal-halide UV lamp that generated high UV irradiance while controlling temperature and humidity. The test protocol contained two alternating phrases. In the first phase, the UV light was controlled at a broadband 300 to 400 nm UV irradiance at 1500 W/m
2, the temperature was controlled at 63 ± 2.5 °C, and the relative humidity was controlled at 60 ± 10 %. The first phase occurred for 110 minutes. In the second phase, the UV light was controlled at a broadband 300 to 400 nm UV irradiance at 1500 W/m
2, the temperature was controlled at 63 ± 2.5 °C and the test specimens are wet with a water spray. The second phase occurred for 10 minutes. After the second phase ended, the first phase started again. This cycle continued for the duration of the testing. The testing specimens were die cut from compression molded plaques. For color index change, 2”x2” square specimens were used. For elongation retention, five replicates of ASTM D1708 micro-tensile bars with 3 mm thickness were used. [0039] Elongation Retention [0040] Elongation retention of test specimens was determined using the Super UV aging process described hereinabove for 115 hours. The ultimate tensile elongation of the test specimen before and after the Super UV aging was compared, and the elongation retention of the test specimen was determined by calculating the percent difference between the two values. [0041] Color Index Change [0042] Color index change of test specimens was determined using the Super UV aging process described hereinabove for 270 hours. The color of the test specimen before and after the Super UV aging was compared. Color characterization was carried out using Datacolor SF 600 CT Plus color spectrometer with D65 illuminant. The instrument output results in CIE L*a*b* color scale. The total color shift, delta E, was reported here to compare the degree of discoloration. [0043] Scratch and Mar Test
85693-WO-PCT/DOW 85693 WO [0044] The scratch and mar test was conducted on a Rockwood Systems and Equipment Five Finger Scratch and Mar Tester. The tester had 5 metal fingers that were 250 mm in length mounted in parallel on a common pivot axis. Scratch pins 1 mm in diameter were mounted on the lower edge of the metal fingers at a distance of 200 mm from the pivot. On the upper edge, 4 holes were placed 15 mm apart at positions 135 mm, 150 mm, 165 mm, and 180 mm from the pivot. Weights having two pins on the longer narrow edge of the plate, centered about the center of mass of the plate, and 15 mm apart were placed in the center positions of three total on the upper surface of the metal fingers. The weights were 140.8 g, 278.5 g, 554.9 g, 693.3 g, and 1124.3 g. Test specimens were taped to a moveable sledge that sits under the pins of the tester. The metal fingers were lowered onto the specimen and the contact point (i.e. starting point) was marked with a permanent marker. The sledge with sample was then dragged under the pins at a speed of approximately 4 inches per second. The metal fingers were then lifted off the sample and the sample was removed. [0045] The degree of damage to the sample was quantified using laser scanning confocal microscopy (LSCM) to analyze the depth of the scratches on the surface of each sample. The instrument used was a Keyence VK-X200K LSM. To capture both the scratch and flat plane around each scratch, a 20x objective lens was used to collect a 3x5 mosaic of that was stitched into a surface model of the scratch. Keyence VK Analyzer software was used in analyzing the average depth profile of the scratch. For each sample, forty individual line profiles were used to generate the average profile. Measurement was made of the height of the deepest part of the scratch trough and compared with the height of the surrounding flat plane of the plaque (plane-to- trough); measurements were also made from the deepest part of the scratch tough and compared with the raised ridge that runs adjacent to the scratch (ridge-to-trough). EXAMPLES [0046] The following examples are offered by way of illustration and are presented in a manner such that one skilled in the art should recognize are not meant to be limiting to the present disclosure as a whole or to the appended claims. [0047] Non-Ionomer Resins
85693-WO-PCT/DOW 85693 WO [0048] UNIVAL DMDA-6220 is a high density polyethylene resin with a density of 0.953 g/cm
3 and a melt index (I2) of 0.38 g/10 min commercially available from Dow Inc, Midland, MI. [0049] CYASORB UV-1164 (C1164), which is a commercial triazine UV absorber commercially available from Solvay USA Inc, Cincinnati, OH, was used as a UV absorber. [0050] CYASORB UV-5411 (C5411), which is a commercial benzotriazole UV absorber commercially available from Solvay USA Inc, Cincinnati, OH, was used as a UV absorber. [0051] CYASORB UV-3346 (C3346), which is a commercial hindered amine light stabilizer commercially available from Solvay USA Inc, Cincinnati, OH, was used as a light stabilizer. [0052] All ethylene/MAA copolymers were prepared by standard free-radical copolymerization methods, using high pressure, operating in a continuous manner. Monomers are fed into the reaction mixture in a proportion, which relates to the monomer's reactivity, and the amount desired to be incorporated. In this way, uniform, near-random distribution of monomer units along the chain is achieved. Polymerization in this manner is well known, and is described in U.S. Pat. No. 4,351,931 (Armitage), which is hereby incorporated by reference. Other polymerization techniques are described in U.S. Pat. No. 5,028,674 (Hatch et al.) and U.S. Pat. No. 5,057,593 (Statz), both of which are also hereby incorporated by reference. The ionomers of these acid copolymers were prepared using the following procedure. [0053] The ionomers of this invention may be prepared by standard neutralization techniques, as disclosed in U.S. Pat. No.3,264,272 (Rees), which is hereby incorporated by references. Other neutralization techniques are described in U.S Pat. No. 3,404,134 (Rees) and U.S. Pat. No. 3649578 (Bush et al.), which is hereby incorporated by reference. The various neutralization ions and the neutralization percentage, as well as some additional properties, are shown in Table 1. Table 1: Melt Index (I2), Ion Type, Initial Acid, and Neutralization Percentage
85693-WO-PCT/DOW 85693 WO
[0054] Test samples comprising the components of Table 2 were prepared as follows. Resin pellets (e.g. ionomer) and UV additives were dry blended first in a plastic liner, and then the blended pellets and additives were compounded in a Coperion ZSK 26 mm twin-screw extruder whose length is 44 and diameter is 26 mm. The melt temperature was 220-235
0C, the screw speed was 300 rpm, and the output was 6.8~9.1 kg/hr. [0055] The compounded materials were then extruded thru a 3 mm, 2-hole die, dropping into a 6-foot-long chilled water bath. The strands made a single pass through the water bath. Next, the strands were pelletized using a Conair 304 strand pelletizer. The finished pellets were dried with nitrogen in a fume hood overnight. [0056] The finished pellets were then formed into a plaque with the dimension of 127 mm in length, 127 mm in width and 3 mm in thickness via compression molding at 180~190 °C according to ASTM D4703 per Appendix A1. Table 2: Composition of Tested Samples
85693-WO-PCT/DOW 85693 WO
[0057] The compression molded plaque samples of Table 2 underwent a scratch and mar test, with the results provided in Table 3. The scratch surface is from the metal finger with the weight of 1124.3 g. (see the section of Scratch and Mar Test) Table 3: Results of the Scratch and Mar Test
85693-WO-PCT/DOW 85693 WO
[0058] The elongation retention and color index change were tested for the compression molded plaque samples of Table 2 with the results shown in Table 4. Table 4: Elongation Retention and Color Index Change
[0059] As shown in Table 4 above, all of the samples that included an ionomer including an ethylene acid copolymer including greater than 8 wt.% carboxylic acid monomers (i.e. Sample IDs CE5-CE15) all failed to have an elongation retention of higher than 85% after 115 hours Super UV aging. This shows the importance of having 6 wt.% or less carboxylic acid monomer in the composition described herein. Furthermore, the samples that included an ionomer including an ethylene acid copolymer including greater than 8 wt.% carboxylic acid monomers failed to have
85693-WO-PCT/DOW 85693 WO an elongation retention of higher than 85% after 115 hours Super UV aging regardless of whether a triazine-based UV absorber or a benzotriazole-based UV absorber was used, further highlighting the criticality of having 6 wt.% or less carboxylic acid monomer in the composition described herein. [0060] Furthermore, samples having only 4 wt.% carboxylic acid monomers also failed to have an elongation retention of higher than 85% after 115 hours Super UV aging when a benzotriazole UV absorber was used, as demonstrated by Sample IDs CE1-CE4, thus highlighting the importance of using a triazine UV absorber. [0061] Additionally, the presence of a polyethylene additive did not allow Sample ID CE15, which has greater than 8 wt.% carboxylic acid monomers, to achieve an elongation retention of higher than 85% after 115 hours Super UV aging, even when a triazine UV absorber was used. However the elongation retention of samples with 6 wt.% or less carboxylic acid monomer were largely unaffected by the presence of a polyethylene additive, as can be seen by comparing Sample IDs IE1-IE3 with Sample IDs IE4-IE6. [0062] Interestingly, comparing Sample ID CE16 to Sample IDs IE3 and IE6 show that while an elongation retention higher than 85% after 115 hours Super UV aging was achieved for samples having 75 mol.% of the carboxylic acid monomers are neutralized with zinc cations, when greater than 75 mol.% of the carboxylic acid monomers are neutralized with zinc cations, an elongation retention higher than 85% after 115 hours Super UV aging is not achieved. [0063] Of additional note, samples neutralized with sodium cations exhibited a color index change less than 5.0 after 270 hours Super UV aging, as shown in Sample IDs IE1, IE3, IE4, and IE6. However, Sample IDs IE2 and IE4 failed to exhibit a color index change less than 5.0 after 270 hours Super UV aging, but still maintained an elongation retention higher than 85% after 115 hours Super UV aging. [0064] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In case of conflict, the specification, including definitions, will control.
85693-WO-PCT/DOW 85693 WO [0065] Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of various examples, suitable methods and materials are described herein. [0066] Unless stated otherwise, all percentages, parts, ratios, etc., are by weight. When an amount, concentration, or other value or parameter is given as either a range, preferred range, or a list of lower preferable values and upper preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any lower range limit or preferred value and any upper range limit or preferred value, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof, and all integers and fractions within the range. It is not intended that the scope of the present disclosure be limited to the specific values recited when defining a range. [0067] As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “containing,” “characterized by,” “has,” “having,” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Further, unless expressly stated to the contrary, “or” refers to an inclusive or and not to an exclusive or. [0068] The transitional phrase “consisting essentially of” limits the scope of a claim to the specified materials or steps and those that do not materially affect the basic and novel characteristic(s) of the disclosure. Where applicants have defined an embodiment or a portion thereof with an open-ended term such as “comprising,” unless otherwise stated, the description should be interpreted to also describe such an embodiment using the term “consisting essentially of.” [0069] Use of “a” or “an” are employed to describe elements and components of various examples. This is merely for convenience and to give a general sense of the various examples. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.
[0054] Test samples comprising the components of Table 2 were prepared as follows. Resin pellets (e.g. ionomer) and UV additives were dry blended first in a plastic liner, and then the blended pellets and additives were compounded in a Coperion ZSK 26 mm twin-screw extruder whose length is 44 and diameter is 26 mm. The melt temperature was 220-2350C, the screw speed was 300 rpm, and the output was 6.8~9.1 kg/hr. [0055] The compounded materials were then extruded thru a 3 mm, 2-hole die, dropping into a 6-foot-long chilled water bath. The strands made a single pass through the water bath. Next, the strands were pelletized using a Conair 304 strand pelletizer. The finished pellets were dried with nitrogen in a fume hood overnight. [0056] The finished pellets were then formed into a plaque with the dimension of 127 mm in length, 127 mm in width and 3 mm in thickness via compression molding at 180~190 °C according to ASTM D4703 per Appendix A1. Table 2: Composition of Tested Samples
85693-WO-PCT/DOW 85693 WO
[0057] The compression molded plaque samples of Table 2 underwent a scratch and mar test, with the results provided in Table 3. The scratch surface is from the metal finger with the weight of 1124.3 g. (see the section of Scratch and Mar Test) Table 3: Results of the Scratch and Mar Test
85693-WO-PCT/DOW 85693 WO
[0058] The elongation retention and color index change were tested for the compression molded plaque samples of Table 2 with the results shown in Table 4. Table 4: Elongation Retention and Color Index Change