摘要 |
A low viscosity, low VOC content fumigation adhesive formulation which is comprised of a) 100 parts by weight (pbw) of a blend of a styrene-diene triblock copolymer, hydrogenated or unhydrogenated, having a weight average molecular weight of 30,000 to 200,000 and a polystyrene content of from 10 to 40% by weight of the polymer, and a styrene-diene diblock copolymer having a weight average molecular weight of 10,000 to 40,000 and a polystyrene content of from 10 to 40% by weight of the polymer, wherein the diblock comprises from 60 to 95% by weight of the polymer blend, b) 75 to 275 parts by weight (pbw) of a tackifying resin which is compatible with the diene blocks, and c) 50 to 200 parts by weight (pbw) of a solvent for the polymer. In its preferred embodiment, the invention is the use of SI diblock polymer with a much smaller amount of conventional SEBS or SEPS triblock polymer to produce an extremely low viscosity product which can be processed in the type of equipment presently in use by fumigation adhesive manufacturers and satisfies the VOC standard of 250 grams per liter or less.
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