Patents by Inventor Richard W. Howery

Patent number: 5672664
Abstract: A thermoplastic molding composition including at least one polycarbonate resin which is a polycarbonate homopolymer or copolymer; and an amount of at least one tetrahalobisphenol A copolymer effective to reduce the yellowness index of the at least one polycarbonate resin as determined after thermally molding the composition into an article. The article molded from the thermoplastic molding composition has a lower yellowness index than that of an article molded from a corresponding thermoplastic molding composition which does not contain any of the at least one tetrahalobisphenol A copolymer.
Type: Grant
Filed: July 15, 1996
Issued: September 30, 1997
Assignee: General Electric Company
Inventors: James L. DeRudder, Richard W. Howery
Patent number: 4686277
Abstract: A process for separating solid cyclic oligomeric dihydric phenol carbonate from solid high molecular weight linear aromatic polycarbonate which comprises admixing an organic solvent with a composition comprising major quantities of solid high molecular weight linear aromatic polycarbonate and minor quantities of solid cyclic oligomeric dihydric phenol carbonate and separating the cyclic oligomeric dihydric phenol carbonate soluble in the organic solvent from the high molecular weight linear aromatic polycarbonate insoluble in the organic solvent, said organic solvent selected so that a very large fraction of the said solid cyclic oligomer is separated from a very large fraction of the said polycarbonate which remains as a solid in the organic solvent.
Type: Grant
Filed: December 23, 1985
Issued: August 11, 1987
Assignee: General Electric Company
Inventors: Richard W. Howery, Niles R. Rosenquist, Robert A. Pyles, Patrick J. Mulvey