Kyung A SuhHouston, TX

6225364, May 1, 2001

Aug 1, 2000

9/581337

Bharat I. Chaudhary - Pearland TX
Kyung W. Suh - Midland MI
Andrew N. Paquet - Saginaw MI

The Dow Chemical Company - Midland MI

C08J 912
C08J 914

521 82

Disclosed is an extruded, dimensionally stable, closed cell alkenyl aromatic polymer foam. The foam comprises an alkenyl aromatic polymer material greater than 50 percent by weight of alkenyl aromatic monomeric units. The foam has a density of about 16 to about 64 kilograms per cubic meter. The foam has a thickness in cross section of 15 millimeters or more. The foam has a blowing agent composition comprising a primary blowing agent of about 70 to about 95 weight percent 1,1,2,2-tetrafluoroethane and a secondary blowing agent comprising about 30 to about 5 weight percent based upon the total moles of the blowing agent composition. The secondary blowing agent being selected from the group consisting essentially of 1,1,1,2-tetrafluoroethane, carbon dioxide, nitrogen, argon, and water. Further disclosed is a process for making the foam.

5717000, Feb 10, 1998

Feb 20, 1997

8/803565

Seema V. Karande - Missouri City TX
Jitka H. Solc - Midland MI
Kyung W. Suh - Granville OH

The Dow Chemical Company - Midland MI

C08J 900

521 83

This invention relates to a polymer foam prepared by dispersing an organophilic multi-layered material into a melt comprising an olefinic or styrenic polymer having polar functionality so that at least a portion of the polymer intercalates between layers of the particles; and expanding the polymer with a blowing agent under such condition to form the polymer foam. The organophilic multi-layered material can also be dispersed into an olefinic or styrenic monomer, which can then be polymerized to form a polymer melt prior to, or along with the foaming step.