Processes for producing polycarbonate and molded polycarbonate articles
US8546515B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 2008 |
| Grant date | Oct 1, 2013 |
| Priority date | — |
| Expiry date | Nov 1, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/1352
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A subject for the invention relates to processes for producing a polycarbonate containing a plant-derived starting material and to molded articles thereof, the polycarbonate having excellent mechanical strength, heat resistance, a low refractive index, a large Abbe number, low birefringence, and excellent transparency. The invention relates to a process for producing a polycarbonate which includes a step in which one or more dihydroxy compounds including a dihydroxy compound having at least one linking group —CH2—O— in the molecule thereof are reacted with a carbonic acid diester in the presence of a polymerization catalyst, wherein the dihydroxy compound having at least one linking group —CH2—O— in the molecule thereof has a formic acid content lower than 20 ppm. The invention further relates to a molded article constituted of a polycarbonate or a composition of the polycarbonate, the polycarbonate being a polycarbonate which contains constituent units derived from a dihydroxy compound having at least one linking group —CH2—O— in the molecule thereof and has an Abbe number of 50 or larger and a 5% weight loss temperature of 340° C. or higher.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.