Patent ID: 7001950

Claim:
An elastomeric composition comprising: a. about 50 to about 80 weight percent of a linear hydrogenated block copolymer consisting of four alternating blocks having the block arrangement of A 1 -B 1 -A 2 -B 2 wherein: (i) each polymer block B 1 and B 2 comprises polymerized, hydrogenated butadiene monomer units in which at least 90% of the olefinically unsaturated double bonds contained in the unhydrogenated polymer block are hydrogenated, and in which the unhydrogenated polymer block have a 1,2-vinyl bond content of greater than 25% and less than 60%; (ii) each polymer block A 1 and A 2 comprises polymerized mono alkenyl arene monomer units; (iii) the number average molecular weights of the blocks are between 6,000 and 8,000 for the A 1 block, between 55,000 and 70,000 for the B 1 block, between 7,500 and 9,000 for the A 2 block and between 5,000 and 12,000 for the B 2 block; and (iv) wherein said linear hydrogenated block copolymer has an order-disorder temperature of less than 240° C., a melt flow rate of less than 2.0 g/10 minutes as measured at 200° C. under a load of 5kg in accordance with ASTM D1238 and a melt flow rate of between 4.0 and 20.0 g/10 minutes as measured at 250° C. under a load of 5kg in accordance with ASTM 1238D; b. about 4 to about 15 weight percent of a styrene polymer selected from the group consisting of crystal polystyrene and anionically polymerized polystyrene; c. about 5 to about 20 weight percent of an olefin polymer selected from the group consisting of ethylene polymers and copolymers, propylene polymers and copolymers, and butylene polymers and copolymers; and d. about 0 to about 25 weight percent of a tackifying resin.