E.i. Dupont De Nemours and Company

Chi-Kai Shih

Daniel Gregory Tynan

John Francis Hagman

Michael Joseph Piovoso

Paul Thomas Shea

Mark David Wetzel

Rita S McMinn

Disclosed is a process for controlling extrusion processes by applying dynamic periodic pulses to the process throughout and during the process, analyzing the pulse response data and feeding back the results of the analysis to the process parameters and product properties.

Method for control of extrusion process

A staged feeding process for preparing a composition by mixing at least a first polymer and a second, dissimilar polymer forms a final composition comprising a uniform, small-particle dispersion of the first polymer in a matrix of the second polymer. Preferably, the first polymer has a melt viscosity greater than the second polymer. The process comprises the steps of feeding the first polymer in a first feed stage and feeding all of the second polymer as a melt at least two feed stages to mix the first and second polymers. Alternatively, the process may comprise feeding the first polymer in a first feed stage and feeding all of the second polymer in at least two feed stages subsequent to the first feed stage. In either case, this mixing initiates a chemical reaction between the first and second polymers.

Staged feeding process for mixing polymers

The processability of an uncured soft elastomer is improved by blending the elastomer under shear conditions with a terpolymer of ethylene with carbon monoxide and with a copolymerizable ethylenically unsaturated monomer in the presence of a crosslinking agent for polymer (T) which does not substantially cure elastomer (E). Gel resulting from crosslinking polymer (T) improves the properties of the blend as compared with the soft elastomer alone. When elastomer (E) and the crosslinking agent for polymer (T) risk undergoing a reaction which would result in substantially crosslinking elastomer (E), one may substitute another soft elastomer (E.sub.1) for elastomer (E) to avoid this undesirable result and then blend the resulting composition with elastomer (E).

Elastomeric sol/gel blends

Copolyesters blended with ethylene/carboxylic acid copolymer in which at least 10% of the acid groups are neutralized have increased melt strength, and are more readily processable by blow molding and extrusion film blowing techniques. The blends contain from 0.2 to 20% by weight of the ethylene/acid copolymer.

Blends of copolyesters and ethylene/carboxylic acid copolymers which are

An elastomer comprising a blend of (A) an ethylene copolymer and (B) a copolyetherester derived from a dicarboxylic acid, a diol, and a poly(oxyalkylene)glycol.

Growing community of inventors

Wilmington, DE, United States of America

Chi-Kai Shih