Patent ID: 6402865
Filing Date: 2002-06-11
Classification: B29C,B32B,C08J

Abstract:
A method for producing an integral multi-layered polymer of nano-layered morphology comprising multiple layers of polymer material and discontinuous gas-containing gaps between adjacent polymer layers, the method, comprising(a) welding together a plurality of pieces of a parent polymeric material at a selected pressure and temperature, for a time sufficient to introduce interfacial entanglements between polymer chains in adjacent pieces such that the degree of interfacial chain entanglement is lower than within the parent polymer, (b) exposing the polymer material thus processed to an inert gas blowing agent to achieve a certain level of solubility of the blowing agent in the polymer, and (c) removing the polymer from the blowing agent to an environment at a pressure of 0 to 2 atm and processing the polymer at a selected temperature below the Tg of the polymer/blowing agent combination for a time sufficient to break the interfacial entanglements, to produce a multi-layered polymer of nano-layered morphology.