Multicomponent nitrile resin-block copolymer-polymer blends

Claim 1

A composition comprising the admixture obtained by intimately mixing about 4 to about 40 parts by weight of a block copolymer, about 5 to about 48 parts by weight of at least one dissimilar engineering thermoplastic, and a nitrile barrier resin in a weight ratio of nitrile barrier resin to dissimilar engineering thermoplastic of greater than 1:1, so as to form a polyblend wherein at least two of the polymers have at least partial continuous interlocked networks with each other and wherein: (a) said block copolymer comprises at least two monoalkenyl arene polymer end blocks A and at least one substantially completely hydrogenated conjugated diene polymer mid block B, said block copolymer having an 8 to 55 percent by weight monoalkenyl arene polymer block content, each polymer block A having an average molecular weight of between about 5,000 and about 125,000, and each polymer block B having an average molecular weight of between about 10,000 and about 300,000; (b) said nitrile barrier resin has an alpha, betaolefinically unsaturated mononitrile content of greater than 50%, a generally crystalline structure, and a melting point over about 120° C.; and (c) said dissimilar engineering thermoplastic resin is capable of forming a continuous structure and is selected from the group consisting of polyamides, saturated thermoplastic polyesters, and fluorinated thermoplastics wherein said saturated polyester has a molecular weight in excess of about 20,000, a melting point over about 120° C. and is selected from the group consisting of (i) the condensation product of a dicarboxylic acid and a glycol, (ii) polypivalolactone, and (iii) polycaprolactone.