Extrudable pressure sensitive adhesive composition and methods for preparing the same
View Patent ↗A phase-separated polymeric composition comprising a first phase including polyurethane domains; and a second phase including a butyl rubber matrix.
1. A phase-separated polymeric composition comprising:
i. a first phase including polyurethane domains; and
ii. a second phase including a butyl rubber matrix, wherein the polyurethane includes mer units deriving from a phenolic resin and mer units deriving from a diisocyanate, wherein said polyurethane domains are discrete domains within said butyl rubber matrix at a temperature of up to about 80° C. and the polyurethane domains have a mean particle diameter of less than 10 μm, and wherein the polyurethane domains are bonded to the butyl rubber through a phenolic resin couple.
2. The composition of claim 1 , where the composition further comprises an oil.
3. The composition of claim 1 , where the composition further comprises a tackifier resin.
4. The composition of claim 1 , where the said polyurethane domains are discrete domains within said butyl rubber matrix at a temperature of up to about 37° C.
5. The composition of claim 1 , where the polyurethane domains have a mean particle diameter of 0.1 to 10 μm.
6. The composition of claim 1 , where the butyl rubber is crosslinked.
7. The composition of claim 2 , where the composition further comprises a tackifier resin.
8. The composition of claim 1 , where the composition demonstrates tack.
9. The composition of claim 1 , where the composition includes at least 35% by weight butyl rubber, based upon the entire weight of the composition.
10. The composition of claim 9 , where the composition includes at least 8% by weight polyurethane based upon the entire weight of the composition.
11. The composition of claim 1 , where the composition includes at least 45% by weight butyl rubber, based upon the entire weight of the composition.
12. The composition of claim 11 , where the composition includes at least 12% by weight polyurethane based upon the entire weight of the composition.
13. The composition of claim 1 , where the composition demonstrates a peel strength (ASTM D413; aged 24 hours at room temperature and tested at room temperature) of at least 3.0 pounds per lineal inch.
14. The composition of claim 1 , where the composition demonstrates a peel strength (ASTM D413; aged 24 hours at room temperature and tested at room temperature) of at least 4.0 pounds per lineal inch.