Toughened compositions of polyamide and functionalized rubber block or graft copolymers

A multiphase composition which is a reaction product formed by mixing a nylon and a block or graft copolymer, said mixing step being a melt blending or a dry mixing followed by melt mixing at a temperature at from about 400.degree. F. to about 650.degree. F. and at a shear rate from about 500 sec..sup.-1 to about 2000 sec..sup.-1 and comprising:

• from about 5 to about 95 percent by weight of said nylon,
• from about 5 to about 95 percent by weight of said block or graft copolymer which is formed by mixing at a reaction temperature of from about 200.degree. to about 500.degree. F. and at a shear rate of from about 500 sec..sup.-1 to about 2000 sec..sup.-1 in the presence of free radicals so as to cause a chemical coupling of at least a first and second polymer components, said first polymer component comprising one or more rubber polymers and said second polymer component comprising one or more reactive polymer having a reactive functionality reactive with said nylon, said reactive polymer having a mole fraction of less than 0.5 of said reactive functionality, said reactive functionality being selected from the group consisting of an unsaturated dicarboxylic acid, an unsaturated monocarboxylic acid, an anhydride of a dicarboxylic acid, a monoester, a sulfonic acid, and an epoxy, or said reactive polymer having a salt of said reactive functionality;
• said rubber containing unsaturation and having a glass transition temperature of minus 40.degree. C. or less or an elongation of 100 percent or greater at room temperature and comprising at least one of said polymers or copolymers made from one or more of butadiene, ethylene propylene diene monomer, isoprene, and neoprene;
• or at least one of polymers or copolymers of halogenated unsaturated rubber, polyisoprene, nitrile rubbers, unsaturated polyurethane rubber, unsaturated polyester rubbers, and unsaturated block copolymers, having a glass transition temperature of minus 40.degree. C. or less.