LOW RESIDUAL SOLVENT POLYAMIDEIMIDE POWDER FROM SUSPENSION POLYMERIZATION
Disclosed is a method for generating a fine slurry of polyamideimide resin which can be conveniently isolated and dried. The product is completely free of dialkylamide solvents or other toxic substances.
1 . A process for producing polyamideimide comprising:
using an aprotic solvent which is a low boiling compound;
using suspension polymerization;
using high pressure processing; and
using high temperature processing to produce a polyamideimide resin in the form of a slurry, solid or semi-solid.
2 . The process of claim 1 where content of the low boiling solvent is used in the process at from about 80 to about 100% of the total solvent content.
3 . The process of claim 1 where the produced polyamideimide resin contains less than about 10% residual low boiling solvent by suspension polymerization.
4 . The process of claim 1 where the low boiling solvent is acetone, ethyl acetate, dimethyl carbonate, or propylene carbonate.
5 . The process of claim 1 where the solvent is acetone.
6 . The process of claim 1 where the suspension polymerization process is an ionic suspension polymerization.
7 . The process of claim 1 where the reaction temperature is from about 56° C. to about 140° C.
8 . The process of claim 1 where the pressure is from about 0 to about 120 psig.
9 . The process of claim 1 where the produced polyamide has a particle size of less than or equal to about 200 microns.
10 . The process of claim 1 where the produced polyamide has a particle size of less than or equal to about 150 microns.
11 . A process of claim 1 where the resultant slurry is spray dried.
12 . The polyamideimide product of the process of claims 1 - 11 .