http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-1411925-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_c7ad58d3c0b071069a8ee0cb8c8ba2e8 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C08G64-28 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C08G64-08 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C08G64-24 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08G64-00 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08G63-00 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08G64-08 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08G64-24 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08G64-28 |
| filingDate | 1974-03-29-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1975-10-29-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-1411925-A |
| titleOfInvention | Process for the preparation of halogen-substituted aromatic polycarbonates |
| abstract | 1411925 Preparing polycarbonates BAYER AG 29 March 1974 [30 March 1973 20 Feb 1974] 14021/74 Heading C3R A process for preparing a polycarbonate from one or more aromatic dihydroxy compounds of which 50-100 mole per cent are tetrahalobisphenols comprises reacting the aromatic dihydroxy compounds with phosgene under phase boundary condensation conditions wherein (i) an aqueous alkaline solution of the bisphenols is reacted with phosgene in the presence of 2-20 mol per cent of a catalyst (referred to the dihydroxy compound) and at a pH of 7 to 9 to give an oligocarbonate with an end group ratio of chlorocarbonic acid ester to hydroxyl of more than 1.1 ; 1 and (ii) polycondensing the oligocarbonate at a pH of more than 13 and a hydroxyl concentration (referred to the aqueous phase) between 0.20 and 0.40% by weight. The examples describe preparing polycarbonates from tetra-chloro or bromo-bisphenol, optionally with bisphenol A using triethylamine as catalyst and p-tert-butylphenol or tribromophenol as chain stoppers. The polycarbonates may have a molecular weight between 5000 and 50,000. |
| isCitedBy | http://rdf.ncbi.nlm.nih.gov/pubchem/patent/CN-102093548-B |
| priorityDate | 1973-03-30-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 28.