To obtain a graft polymer useful for producing a high-damping soft material by extending with an oil or a low-molecular-weight component by reacting a poly(alkenylbenzene-co-maleimide) having a small or trace amount of maleic anhydride monomer units with a nylon in a specified ratio.
About 20 to 99 wt.% poly(alkenylbenzene-co-maleimide) having a small or trace amount of maleic anhydride monomer units is reacted with about 1 to 80 wt.% nylon under substantially dry conditions favorable for forming a nylon graft polymer. The poly(alkenylbenzene-co-maleimide) is obtained by reacting a poly[alkenylbenzene-co-maleic anhydride], desirably, poly(strene-co-maleic anhydride) at about 120 to 250°C in the presence of a primary amine at a pressure slightly higher than vacuum to about 20 atm. under substantially dry conditions. In this reaction, at most 5%, most desirably, at most 1% maleic anhydride is left unreacted.
FOLTZ VICTOR J
HALL JAMES E
MASHITA SHIGEHIKO
TAKECHI HIDEO
