Polyamide blends by reactive processing
AssigneeThe Dow Chemical Company
InventorsRobert G. Nelb, II, Kemal Onder
Life of this patent
Estimating the term…
Abstract
Disclosed is a process for the preparation of a thermoplastic polymer blend comprising a first preformed thermoplastic polymer such as a polyester, polycarbonate, ABS graft polymer and the like and a second thermoplastic polyamide or polyamideimide. The second polymer is prepared from a diisocyanate and polycarboxylic compund selected from a dicarboxylic acid, tricarboxylic acid or anhydride thereof, or mixtures of these components by reactively processing the monomer components in the presence of the first polymer.
Claims30
A process for the preparation of a thermoplastric polymer blend containing at least one first thermoplastic polymer and a second thermoplastic polymer, the second thermoplastic polymer having recurring imide and/or amide linkages which process comprises (a) mixing the first thermoplastic polymer with an organic diisocyanate and a polycarboxylic compound selected from the class consisting of a dicarboxylic acid, a tricarboxylic acid or anhydride thereof, and mixtures of said dicarboxylic and tricarboxylic acid or anhydride thereof at a temperature below the melting point of the first polymer and (b) reactively processing the mixture of step (a) whereby the second thermoplastic polymer is formed by the reaction of the organic diisocyanate with the polycarboxylic compound in the presence of said first polymer thereby forming said thermoplastic polymer blend.
A process for the preparation of a thermoplastic polymer blend comprising a first thermoplastic polymer and a second thermoplastic polymer characterized by recurring amide linkages which process comprises:
- (A) adding to the feed zone of a vented twin-screw extruder the components comprising:
- (a) said first thermoplastic polymer:
- and
- (b) said second thermoplastic polymer forming ingredients comprising,
- (i) at least one aromatic diisocyanate or liquefied form thereof:
- (ii) a dicarboxylic acid selected from the group consisting of aromatic dicarboxylic acids, aliphatic dicarboxylic acids, dicarboxylic acid terminated polyesters, dicarboxylic acid terminated polyethers, dicarboxylic acid terminated polycarbonates and mixtures of any two or more such acids wherein the proportions of said (i) and (ii) are such that the ratio of equivalents of carboxylic compound per isocyanate equivalent is from about 0.95 to about 1.05 and that said second polymer comprises from about 5 to about 50 percent by weight of said polymer blend:
- and
- (iii) a phospholene oxide catalyst:
- (B) homogenizing said compounds at a temperature below the melting point of the first polymer:
- (C) fluxing said compounds at a temperature of from about 100.degree. C. to about 350.degree. C.;
- (D) venting the carbon dioxide formed in a vented zone during said fluxing and homogenizing:
- and
- (E) removing the resulting polymer blend from said extruder via a shaping zone.
Dependencies are inferred from the claim text.