JPS6324024B

The instant invention is directed to a process for the modification of a thermoplastic polymer comprising: I. introducing 70 to 98 parts by weight of thermoplastic polymer into an extruder at a first inlet; II. adding to said thermoplastic polymer through a second inlet 2 to 30 parts by weight of the following polyurethane forming components, such that the total parts by weight of the thermoplastic polymer and polyurethane components is 100: (A) organic polyisocyanate; and (B) chain lengthening agent with a molecular weight below 400 containing at least one hydroxyl group and/or amino group; wherein the ratio of isocyanate groups of component (A) to Zerewitinoff active groups of component (B) is in the range of from 0.90:1 to 1.2:1; and III. discharging from the extruder the product of the process.