WO2018083581A1

WO2018083581A1 - Adhesive for ice and water barrier films

Info

Publication number: WO2018083581A1
Application number: PCT/IB2017/056717
Authority: WO
Inventors: George J. Clements; Gregg A. Patnode
Original assignee: 3M Innovative Properties Co
Current assignee: 3M Innovative Properties Co
Priority date: 2016-11-04
Filing date: 2017-10-30
Publication date: 2018-05-11
Anticipated expiration: 2019-05-04

Abstract

Ice and water barrier films are provided which comprise an adhesive layer comprising a rubber blend of polyisoprene and a styrene-isoprene-styrene (S-I-S) block copolymer rubber. In some embodiments, the adhesive layer may comprise polyisoprene and the S-I-S block copolymer in a weight ratio of between 70:30 and 88: 12 and the total combined weight of polyisoprene and the S-I-S block copolymer may be between 36 wt% and 51 wt% of the adhesive layer. In some embodiments, the adhesive layer may comprise at least 10 wt% of a plasticizer and between 20 wt% and 60 wt% of a tackifier. In some embodiments, the adhesive layer has a low Tg, typically less than -20°C, more typically less than -40°C, and more typically less than -50°C. In some embodiments, the ice and water barrier film passes the Nail Seal Ability Test performed according to ASTM D1970.

Description

ADHESIVE FOR ICE AND WATER BARRIER FILMS

Field of the Disclosure

This disclosure relates to adhesives comprising blends of polyisoprene and styrene-isoprene- styrene (S-I-S) block copolymers, and their use in ice and water barrier films.

Background of the Disclosure

Ice and water barrier films are used in roofing systems. In some cases, such films comprise an adhesive layer and a backing layer. Ice and water barrier films are applied to the structural roofing material, typically plywood, where they stick adhesively. Subsequently, shingles are attached to the roof with nails which penetrate the shingles themselves, the ice and water barrier film, and the structural roofing layer.

An ice dam on the bottom of a shingled roof will allow a pool of water to form which can seep under shingles. In the absence of any barrier, this water comes in contact with a non-waterproof roofing layer, typically wood. Over time this wood can rot, causing water leakage or roof failure. The ice and water barrier must exhibit good nail sealing, i.e., it must form a water proof seal around nails.

Currently available products make use of 'asphaltic' or 'bituminous' adhesives. Bitumen is a black viscous mixture of hydrocarbons obtained naturally or as a residue from petroleum distillation. In some cases the bitumen is blended with butyl rubber. Bitumen is inexpensive and hydrophobic, however, it has a relatively high softening temperature (and/or Tg) and thus imparts a high softening temperature (and/or Tg) to the ice and water barrier. As a result, such products require relatively high minimum installation temperatures because they lose tack at low temperatures and will not seal around a nail adequately until exposed to sufficient heat. Since ice and water barrier films are most important to construction in northern climates, these shortcomings are particularly relevant.

Grace Ice & Water Shield® and Grace Ice & Water Shield® HT ("high temperature"), both sold by GCP Applied Technologies, Inc., Cambridge, MA, USA, are commercially available self-adhered roofing underlayments that include a layer of rubberized asphalt adhesive and a backing layer of polyethylene film. The minimum installation temperature is specified as 40°F for both products.

The following references may be relevant to the general field of technology of the present disclosure: JPH1082146 A, JPH06166962 A, US4539344, US4396665, US2012094067 Al, JP5669969, CN203049938U, CN102912998.

Summary of the Disclosure

Briefly, the present disclosure provides an ice and water barrier film comprising an adhesive layer comprising a rubber blend of polyisoprene and a styrene-isoprene-styrene (S-I-S) block copolymer rubber. In some embodiments, the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio of between 70:30 and 88: 12; in some embodiments between 78:22 and 82: 18. In some embodiments, the total combined weight of polyisoprene and the S-I-S block copolymer is between 36 wt% and 51 wt% of the adhesive layer. In some embodiments, the adhesive layer comprises at least 10 wt% of a plasticizer. In some embodiments, the adhesive layer comprises between 20 wt% and 60 wt% of a tackifier. In some embodiments, the adhesive layer has a Tg of less than -20°C as determined via the DSC test method; in some embodiments less than -40°C; and in some embodiments less than -50°C. In some embodiments, the adhesive layer forms an outermost layer of the ice and water barrier film and is available for bonding to a substrate surface. In some embodiments, the ice and water barrier film additionally comprises a backing layer bound to the adhesive layer. In some embodiments, the backing layer is bound directly to the adhesive layer, whereas in other embodiments the backing layer is bound to the adhesive layer through a primer layer, the primer layer being bound directly to both adhesive and backing layers. In some embodiments, the backing layer comprises propylene/ethylene copolymer comprising propylene and ethylene in a weight ratio of at least 2: 1 propylene/ethylene. In some embodiments, the ice and water barrier film passes the Nail Seal Ability Test performed according to ASTM D 1970. In some embodiments, the ice and water barrier film has a thickness of greater than 0.5 mm and less than 5.0 mm. Additional embodiments of the ice and water barrier film of the present disclosure are described below under "Selected Embodiments".

In another aspect, the present disclosure provides a roof comprising: a) a roof substrate; b) an ice and water barrier film according to the present disclosure; and c) shingles; where the shingles are held to the roof substrate by fasteners which penetrate the shingles, the ice and water barrier film, and the roof substrate. In additional aspects, the present disclosure provides methods of making and using the ice and water barrier films of the present disclosure. Additional embodiments are described below under "Selected Embodiments".

All scientific and technical terms used herein have meanings commonly used in the art unless otherwise specified.

As used in this specification and the appended claims, the singular forms "a", "an", and "the" encompass embodiments having plural referents, unless the content clearly dictates otherwise.

As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

As used herein, "have", "having", "include", "including", "comprise", "comprising" or the like are used in their open ended sense, and generally mean "including, but not limited to." It will be understood that the terms "consisting of and "consisting essentially of are subsumed in the term "comprising," and the like.

Detailed Description

The present disclosure provides adhesives comprising blends of polyisoprene and styrene- isoprene-styrene (S-I-S) block copolymer. The present disclosure additionally provides ice and water barrier films incorporating such adhesives. In some embodiments, these ice and water barrier films combine the best of warm- and cold-temperature behavior - maintaining tack and nail sealability at low temperatures for low temperature installation, yet maintaining adhesion without creep at high temperature.

Ice and water barrier films according to the present disclosure typically comprise a layer of adhesive and a backing layer. In some embodiments, the adhesive and backing layers are directly bound together. In some embodiments, they are bound together through an intermediate primer layer. Any suitable backing layer may be used, including polyolefins, such as propylene/ethylene copolymers.

The adhesive layer according to the present embodiment comprises a blend of polyisoprene and styrene-isoprene-styrene (S-I-S) block copolymer. Typically, the adhesive layer additionally comprises tackifier, plasticizer, or most typically both. Additional components may include, without limitations, anti -oxidants, UV stabilizers, pigments, fillers, and the like.

In some embodiments, the styrene-isoprene-styrene (S-I-S) block copolymer is a linear block copolymer. In some embodiments, the styrene-isoprene-styrene (S-I-S) block copolymer is a linear triblock copolymer. In some embodiments, the styrene-isoprene-styrene (S-I-S) block copolymer is a star block copolymer or multi-arm block copolymer. In some embodiments, the styrene-isoprene-styrene (S- I-S) block copolymer is an asymmetric star block copolymer or asymmetric multi-arm block copolymer.

Ice and water barrier films have substantial thickness, typically greater than 0.1 mm but more typically greater than 0.5 mm, 0.7 mm, or 0.8 mm. In some embodiments, the adhesive layer represents 80-95% of that thickness. Such thickness may make uniform cure of adhesive materials difficult, particularly with regard to any form of radiation cure. Thus in some embodiments it is an advantage of the materials of the present disclosure that the adhesive layer requires no cure during or after application to the backing layer. Selected Embodiments

The following embodiments, designated by letter and number, are intended to further illustrate the present disclosure but should not be construed to unduly limit this disclosure.

Fl . An ice and water barrier film comprising an adhesive layer comprising a rubber blend of polyisoprene and a styrene-isoprene-styrene (S-I-S) block copolymer rubber.

F2. The ice and water barrier film according to embodiment Fl wherein the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio of between 70:30 and 88: 12. F3. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio limited to not less than 72:28. F4. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio limited to not less than 74:26.

F5. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio limited to not less than 76:24.

F6. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio limited to not more than 86: 14.

F7. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio limited to not more than 84: 16.

F8. The ice and water barrier film according to embodiment Fl wherein the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio of between 78:22 and 82: 18.

F9. The ice and water barrier film according to any of the preceding embodiments wherein the total combined weight of polyisoprene and the S-I-S block copolymer is between 36 wt% and 51 wt% of the adhesive layer.

F10. The ice and water barrier film according to any of the preceding embodiments wherein the total combined weight of polyisoprene and the S-I-S block copolymer is limited to not more than 49 wt% of the adhesive layer.

Fl 1. The ice and water barrier film according to any of the preceding embodiments wherein the total combined weight of polyisoprene and the S-I-S block copolymer is limited to not more than 48 wt% of the adhesive layer. F12. The ice and water barrier film according to any of the preceding embodiments wherein the total combined weight of polyisoprene and the S-I-S block copolymer is limited to not more than 47 wt% of the adhesive layer. F13. The ice and water barrier film according to any of the preceding embodiments wherein the total combined weight of polyisoprene and the S-I-S block copolymer is limited to not less than 40 wt% of the adhesive layer.

F14. The ice and water barrier film according to any of the preceding embodiments wherein the total combined weight of polyisoprene and the S-I-S block copolymer is limited to not less than 43 wt% of the adhesive layer.

F15. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises at least 6 wt% of a plasticizer.

F16. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises at least 10 wt% of a plasticizer.

F17. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises at least 12 wt% of a plasticizer.

F18. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises no more than 30 wt% of a plasticizer. F19. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises at least 20 wt% of a tackifier.

F20. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises not more than 60 wt% of a tackifier.

F21. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer comprises not more than 45 wt% of a tackifier.

F22. The ice and water barrier film according to any of the preceding embodiments wherein the polyisoprene is a synthetic polyisoprene. F23. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer has a Tg of less than -20°C as determined via the DSC test method.

F24. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer has a Tg of less than -30°C as determined via the DSC test method.

F25. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer has a Tg of less than -35°C as determined via the DSC test method. F26. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer has a Tg of less than -40°C as determined via the DSC test method.

F27. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer has a Tg of less than -45°C as determined via the DSC test method.

F28. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer has a Tg of less than -50°C as determined via the DSC test method.

F29. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer forms an outermost layer of the ice and water barrier film and is available for bonding to a substrate surface.

F30. The ice and water barrier film according to any of the preceding embodiments additionally comprising a backing layer bound to the adhesive layer.

F31. The ice and water barrier film according to any of the preceding embodiments additionally comprising a backing layer bound directly to the adhesive layer.

F32. The ice and water barrier film according to any of the preceding embodiments additionally comprising a backing layer bound to the adhesive layer through a primer layer, the primer layer being bound directly to both adhesive and backing layers.

F33. The ice and water barrier film according to any of embodiments F30-F32 wherein the backing layer comprises polyolefin. F34. The ice and water barrier film according to any of embodiments F30-F32 wherein the backing layer comprises propylene/ethylene copolymer.

F35. The ice and water barrier film according to any of embodiments F30-F32 wherein the backing layer comprises propylene/ethylene copolymer comprising propylene and ethylene in a weight ratio of at least 2: 1 propylene/ethylene.

F36. The ice and water barrier film according to any of the preceding embodiments which passes the Nail Seal Ability Test performed according to ASTM D1970.

F37. The ice and water barrier film according to any of the preceding embodiments having a thickness of greater than 0.1 mm.

F38. The ice and water barrier film according to any of the preceding embodiments having a thickness of greater than 0.5 mm.

F39. The ice and water barrier film according to any of the preceding embodiments having a thickness of less than 5.0 mm. F40. The ice and water barrier film according to any of the preceding embodiments having a thickness of less than 1.2 mm.

Rl . A roof comprising:

a) a roof substrate;

b) an ice and water barrier film according to any of embodiments F1-F40; and

c) shingles;

wherein the shingles are held to the roof substrate by fasteners which penetrate the shingles, the ice and water barrier film, and the roof substrate. MU1. A method of making a roof comprising the steps of:

a) applying an ice and water barrier film according to any of embodiments F1-F40 to a roof substrate; and

b) affixing shingles over the ice and water barrier film.

MU2. The method according to embodiment Ml, wherein the shingles are affixed by application of fasteners which penetrate the shingles, the ice and water barrier film, and the roof substrate. Ml . A method of making an ice and water barrier film according to any of embodiments F1-F40, comprising the step of: :

a) applying a primer to a backing layer to make a primed backing layer; and

b) applying an adhesive material to the primed backing layer to make an ice and water barrier film comprising an adhesive layer bound to the primed backing layer.

M2. The method according to embodiment Ml, wherein the method excludes any step of curing the adhesive material or adhesive layer during or after the step of applying the adhesive material to the primed backing layer.

M3. A method of making an ice and water barrier film according to any of embodiments F1-F40, comprising the step of: :

b) applying an adhesive material to a backing layer to make an ice and water barrier film comprising an adhesive layer bound to the backing layer.

M4. The method according to embodiment M3, wherein the method excludes any step of curing the adhesive material or adhesive layer during or after the step of applying the adhesive material to the backing layer.

Objects and advantages of this disclosure are further illustrated by the following examples, but the particular materials and amounts thereof recited in these examples, as well as other conditions and details, should not be construed to unduly limit this disclosure.

Examples

Unless otherwise noted, all reagents were obtained or are available from Aldrich Chemical Co., Milwaukee, WI, or may be synthesized by known methods.

TABLE 1. Materials

Thermal Stability Test Method

For the thermal stability test, samples of the pressure sensitive adhesive tapes were adhered to a piece 0.25 inch (6.4 mm) piece of plywood substrate, and then the whole taped board was placed in a 70°C oven for two weeks, at a 60° angle (Examples 1-15) or a 45° angle (Examples 16-24 and CE-1), where horizontal = 0° angle. After the two week period, each sample was measured for the amount of travel down the plywood substrate.

Nail Seal Ability Test Method

The Nail Seal Ability Test was performed according to ASTM D1970, which details test methods and limits for properties required for self-adhered, water proof membranes used for ice and water barriers, including nail seal ability. The substrate used was an oriented strand board ("HUBER ZIP SYSTEM ROOF SHEATHING", available from Huber Engineered Wood, Charlotte, NC). Differential Scanning Calorimetrv (DSC) Test Method

DSC was performed using a Q2000 differential scanning calorimeter (TA Instruments), using TA INSTRUMENTS UNIVERSAL ANALYSIS software (TA Instruments) for analysis of the DSC results. For each test, a sample weighing approximately 7 milligrams of adhesive was scraped off of the backing.. The sample was then weighed and placed into an aluminum sample pan. A lid was then crimped onto the sample pan. The prepared sample was then placed into the DSC sample chamber with an empty aluminum reference pan and was ramped from -70°C to 100°C at a ramp rate of 10°C/min. Glass transition temperature (Tg) was identified in the scanning profile of heat flow vs. temperature. Typically, crystallization and melting transitions show up as positive and negative heat flow peaks as the sample is cooled and heated, and the latent heat is given off or absorbed, respectively. Conversely a glass transition is generally represented by a shift in the profile slope upon heating as the heat capacity of the sample after the transition is altered. The glass transition temperature was recorded at the inflection point of the curve associated with this shift in heat flow profile.

Examples 1-15

The pressure sensitive adhesives of Examples 1 to 15 were formulated to include the components according to Table 2. The components were compounded together using a twin screw extruder, and extruded as a rope of about 0.75 inch (about 20 mm) diameter onto a release liner. Pieces of each adhesive were cut out and hot pressed to about 32 to 36 mils (about 810 to 910 micrometers) onto 4 mil (about 100 micrometers) thick film principally comprising propylene/ethylene copolymer resulting in a PSA tape for each of the examples.

TABLE 2

NATSYN QUINTAC QUINTONE KRYSTOL IRGANOX

Example

2210, pbw 3620, pbw K100, pbw 350, pbw 1010, pbw

EX-1 35.4 16.6 30.55 17.5 0.5

EX-2 27.6 18.4 39.24 14.8 0.5

EX-3 36.8 9.2 40.6 13.4 0.5

EX-4 46.0 0.0 41.92 12.1 0.5

EX-5 47.7 4.2 32.19 15.9 0.5

EX-6 36.8 3.2 33.49 26.5 0.5

EX-7 44.8 11.2 39.4 4.6 0.5

EX-8 47.7 4.2 48.1 0 0.5

EX-9 28.8 7.2 41.8 22.2 0.5

EX- 10 35.4 16.6 46.8 1.3 0.5

EX- 11 36.8 9.2 25.84 28.2 0.5

EX- 12 36.8 9.2 53.6 0.4 0.5

EX- 13 36.8 3.2 49.95 10 0.5

EX- 14 27.3 12.8 48.46 11.5 0.5

EX- 15 27.3 12.8 32.12 27.8 0.5

In Table 2, pbw = parts by weig ht Examples 16 to 24

The pressure sensitive adhesives of Examples 16 to 24 were formulated to include the components according to Table 3. The components were compounded together using a twin screw extruder, and extruded onto a 4 mil (about 100 micrometers) thick film principally comprising propylene/ethylene copolymer to a total caliper of about 40 mils.

TABLE 3

In Table 3, pbw = parts by weig

The tapes from Examples 1 to 15 were tested according to the Thermal Stability and Neal Seal Ability Test Methods. A comparative example ("CE-1", GRACE ICE AND WATER SHIELD, available from W. R. Grace and Co., Columbia, MD) was also tested. The results were as summarized in Table 4.

TABLE 4

In Table 4, ND = not determined

Under the tape for EX-1, EX-2, and EX-7, no liquid water was observed but rather a darkening of the substrate board. This darkened spot disappeared over the course of an hour or so, which was taken to mean that the dark spot was due to the presence of water.

180 degree Peel Test Method

The 180 degree peel test method was essentially that described in ASTM D1970D1970M-15a, with the exception of using a lighter application roller of 11 pounds (5 kg). The substrate used was an oriented strand board ("HUBER ZIP SYSTEM ROOF SHEATHING", available from Huber Engineered Wood, Charlotte, NC). Boards, tape samples, and the roller were place in a freezer at the specified temperature (either -15°C or -7°C) for a minimum of 24 hours before the test. After rolling the samples onto the substrate, a 15 minute dwell was called out in the test method specification. Samples were taken out of the freezer chest and tested immediately on an IMASS SP-2000 slip/peel tester (available from

IMASS, Inc., Accord, MA) situated beside the freezer chest, using a peel angle of 180 degrees. For room temperature samples, the samples were laminated (prior to testing) onto substrate at -7°C, and then allowed to warm to room temperature overnight before testing at room temperature. The 180 degree peel test results were as summarized in Table 5. At the cold temperatures (-15°C and -7°C), there was no 180 degree peel test data for the CE-1 material, since the CE-1 material did not develop significant adhesion at those temperatures.

TABLE 5

ASTM D1970D1970M-15a states that at 75°F (24°C), the minimum 180 degree peel strength value for adhesion is 16 ounces per inch (178 grams per cm), and when run at 40°F (4°C) the minimum 180 degree peel strength value for adhesion is 2.7 ounces per inch (30 grams per cm).

Glass transition (Tg) temperatures were also determined via the DSC test method for the materials listed in Table 5.

Various modifications and alterations of this disclosure will become apparent to those skilled in the art without departing from the scope and principles of this disclosure, and it should be understood that this disclosure is not to be unduly limited to the illustrative embodiments set forth hereinabove.

Claims

We claim:

1. An ice and water barrier film comprising an adhesive layer comprising a rubber blend of polyisoprene and a styrene-isoprene-styrene (S-I-S) block copolymer rubber.

2. The ice and water barrier film according to claim 1 wherein the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio of between 70:30 and 88: 12.

3. The ice and water barrier film according to claim 1 wherein the adhesive layer comprises polyisoprene and the S-I-S block copolymer in a weight ratio of between 78:22 and 82: 18.

4. The ice and water barrier film according to any of the preceding claims wherein the total combined weight of polyisoprene and the S-I-S block copolymer is between 36 wt% and 51 wt% of the adhesive layer.

5. The ice and water barrier film according to any of the preceding claims wherein the adhesive layer comprises at least 10 wt% of a plasticizer.

6. The ice and water barrier film according to any of the preceding claims wherein the adhesive layer comprises between 20 wt% and 60 wt% of a tackifier.

7. The ice and water barrier film according to any of claims 1-6 wherein the adhesive layer has a Tg of less than -20°C as determined via the DSC test method.

8. The ice and water barrier film according to any of claims 1-6 wherein the adhesive layer has a Tg of less than -40°C as determined via the DSC test method.

9. The ice and water barrier film according to any of claims 1-6 wherein the adhesive layer has a Tg of less than -50°C as determined via the DSC test method.

10. The ice and water barrier film according to any of the preceding embodiments wherein the adhesive layer forms an outermost layer of the ice and water barrier film and is available for bonding to a substrate surface and wherein the ice and water barrier film additionally comprises a backing layer bound to the adhesive layer.

11. The ice and water barrier film according to claim 10 wherein the backing layer is bound directly to the adhesive layer.

12. The ice and water barrier film according to claim 10 wherein the backing layer is bound to the adhesive layer through a primer layer, the primer layer being bound directly to both adhesive and backing layers.

13. The ice and water barrier film according to any of claims 10-12 wherein the backing layer comprises propylene/ethylene copolymer comprising propylene and ethylene in a weight ratio of at least 2: 1 propylene/ethylene.

14. The ice and water barrier film according to any of the preceding claims which passes the Nail Seal Ability Test performed according to ASTM D1970.

15. The ice and water barrier film according to any of the preceding claims having a thickness of greater than 0.5 mm and less than 5.0 mm.