General Electric Company

Sabic Innovative Plastics IP B.v.

Gerardo Hidalgo

Patrick Joseph McCloskey

Alberto Nisoli

Lina Prada

Patrick J Mccloskey

A method of making polycarbonates comprises melt-polymerizing an aromatic dihydroxy compound and a carbonic acid diester in a presence of a polymerization catalyst in a reactor system producing a byproduct stream, wherein the polymerization catalyst comprises a quaternary phosphonium compound; and purifying the byproduct stream to separate phenol, wherein the separated phenol has a phosphorus concentration of less than or equal to about 3 part per million, based upon the total weight of the phenol separated.

Method for making polycarbonate

A method of making polycarbonate comprises melt-polymerizing an aromatic dihydroxy compound and a carbonic acid diester in a presence of a polymerization catalyst in a reactor system producing a byproduct stream, wherein the polymerization catalyst comprises a quaternary phosphonium compound; and purifying the byproduct stream to separate the carbonic acid diester, wherein the separated carbonic acid diester has a phosphorous concentration of less than or equal to about 30 parts per million.

Growing community of inventors

Cartagena Murcia, Spain

Gerardo Hidalgo