Other

North Carolina State University

The University of North Carolina at Chapel Hill

Srinivas Siripurapu

Joseph Desimone

Saad A Khan

Joseph R Royer

Richard J Spontak

Teri Anne Walker

Yvon J Gay

Polymeric materials having a plurality of cells formed therein are described. The polymeric materials include a foamed layer comprising a plurality of uniform microcells, nanocells or combinations thereof in a closed cell network, a transition layer positioned adjacent to the foamed layer, and at least one unfoamed outer layer positioned adjacent to the transition layer. The foamed layer may be present in a volume ranging from about 80 to about 99 percent based on the volume of the polymeric material, the transition layer may present in a volume ranging from about 0 to about 10 percent based on the volume of the polymeric material, and the at least one outer layer may be present in a volume ranging from about 0.01 to about 10 percent based on the volume of the polymeric material. Methods of making such polymeric materials are also described, as are apparatus for providing foamed polymeric materials.

Nano-and micro-cellular foamed thin-walled material, and processes and apparatuses for making the same

A method of producing a foamed material comprises contacting a mixture comprising a first thermoplastic polymer and a second thermoplastic polymer with a blowing agent, wherein the first thermoplastic polymer has a higher percent crystallinity that the second thermoplastic polymer; and subjecting the mixture to conditions sufficient to create a thermodynamic instability in the blend foam the mixture, wherein the mixture comprising the first and second thermoplastic polymers has a percent crystallinity lower than the first thermoplastic polymer.

Methods of making foamed materials of blended thermoplastic polymers using carbon dioxide

Growing community of inventors

Raleigh, NC, United States of America

Srinivas Siripurapu