Process for poly (bisphenol A/terephthalate/carbonate) using pyridine reaction medium
US4219635A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 26, 1979 |
| Grant date | Aug 26, 1980 |
| Priority date | — |
| Expiry date | Jan 26, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/64
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Poly(ester/carbonates) are produced by adding phosgene to a reaction mixture of bisphenol A and terephthalic acid as ester-forming reactants, at mole ratios in the range between 2.0:0.8 and 2.0:1.3, in which the reaction medium consists essentially of pyridine, the concentration of bisphenol A plus terephthalic acid is in the range between 5 and 50 grams per 100 ml of pyridine; and the phosgene is added under agitation at a rate of at least 0.07 gm-mmole/liter.sec. The process is carried out at temperature in the range between 50.degree. C. and 115.degree. C. and not below the temperature given by the Arrhenius equation: EQU 1nU=10-12/0.001987 T where U is phosgene feed rate in gram-moles/liter.second and T is absolute temperature of the reaction mixture (degrees Kelvin). Preferred phosgene feed rates are at least 0.13 gram-millimoles/liter.second; and preferred temperatures of the reaction mixture are between 60.degree. C. and 80.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.