The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 01, 2006
Filed:
May. 28, 2003
Jong-hun Kim, Daejeon, KR;
Boo-gon Woo, Daejeon, KR;
Eun-duck Park, Incheon, KR;
Mi-jeung Hong, Yeosu, KR;
Jong-Hun Kim, Daejeon, KR;
Boo-Gon Woo, Daejeon, KR;
Eun-Duck Park, Incheon, KR;
Mi-Jeung Hong, Yeosu, KR;
LG Chem, Ltd., Seoul, KR;
Abstract
The present invention relates to a process for preparing high molecular weight polycarbonate resin, particularly to a process for preparing high molecular weight polycarbonate resin, which conducts condensation polymerization of low molecular weight amorphous polycarbonate prepolymer prepared by transesterification of dialkyl(aryl)carbonate and aromatic hydroxy compound and solid state polymerization within short time to increase molecular weight. The present invention introduces condensation polymerization to lower mole fractions of arylcarbonate existing in unreacted diarylcarbonate, end groups of reaction by products of polymerization degree less than 3, and polycarbonate prepolymer obtained by transesterification, and thus can maximize molecular weight increase of polycarbonate after solid state polymerization and remarkably reduce time required for preparing polycarbonate of the same molecular weight. In addition, since the present invention does not use toxic substance phosgene, it has no danger and it can prevent deterioration, and it can prepare high molecular weigh polycarbonate that can be used for injection and extrusion.