Donald G Bright

US Patent:

42568455, Mar 17, 1981

Filed:

Feb 15, 1979

Appl. No.:

6/012433

Inventors:

Harold B. Morris - Newnan GA
Donald G. Bright - College Park GA

Assignee:

Glasrock Products, Inc. - Fairburn GA

International Classification:

B29D 2700

US Classification:

521 61

Abstract:

A porous thermoplastic sheet is formed by adding a material to a polymer latex to passivate the aqueous phase of the latex. An additional material of a preselected particle size, corresponding to the desired pore size of the final product is then added. The latex composition is gelled and is then formed into a sheet. The sheet is dried and cured or sintered and the solubles are extracted therefrom with a solvent. A preferred polymer latex is PTFE.

US Patent:

47612320, Aug 2, 1988

Filed:

Mar 7, 1986

Appl. No.:

6/837182

Inventors:

Donald G. Bright - Tyrone GA

Assignee:

Porex Technologies Corp. of Georgia - Fairburn GA

International Classification:

B01D 1300

US Classification:

21050036

Abstract:

In a porous structure, a macroporous polyethylene substrate defining a network of interconnecting macropores and a microporous matrix of polyvinyl chloride is formed within and completely fills the network of macropores. The microporous matrix is cast within the network of macropores by impregnating the macropores with a solution of a solvent, a polymeric pore former, and polyvinyl chloride. The solution is caused to imbibe water from the atmosphere so as to separate into two liquid phases, one phase being rich in the polyvinyl chloride and the other phase being rich in water. The microporous matrix is coagulated from the first phase and the solvent and pore former are extracted from the macroporous matrix.