http://rdf.ncbi.nlm.nih.gov/pubchem/patent/EP-1414888-A1
Outgoing Links
Predicate | Object |
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assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_c72d118f5664072de841f9c5c34b9d99 |
classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C08G64-307 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C08G64-30 |
classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08G64-30 |
filingDate | 2002-07-17-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
inventor | http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_61b37704065a7068e82b25314faf034a http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_efab709a1ec9831f5cf7829dcd8ec4d8 http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_60bf8f3ae0c510d5947023efedc22616 http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_8d6235a0d145104723060afffd759213 |
publicationDate | 2004-05-06-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
publicationNumber | EP-1414888-A1 |
titleOfInvention | Extrusion method for making polycarbonate |
abstract | Extrusion of a mixture of an ester-substituted diaryl carbonate, such as bis(methyl salicyl) carbonate, a dihydroxy aromatic compound such as bisphenol A and a transesterification catalyst such as tetrabutylphosphonium acetate (TBPA) affords polycarbonate having a weight average molecular weight of greater than 20,000 daltons. The extruder is equipped with one or more vacuum vents to remove by-product ester-substituted phenol. Similarly, a precursor polycarbonate having ester-substituted phenoxy endgroups, for example methyl salicyl endgroups, when subjected to extrusion affords a polycarbonate having a significantly increased molecular weight relative to the precursor polycarbonate. The reaction to form a higher molecular weight polycarbonate may be catalyzed by residual transesterification catalyst present in the precursor polycarbonate, or by a combination of any residual catalyst and an additional catalyst such as TBPA introduced in the extrusion step. Fries rearrangement products are not observed in the product polycarbonates. |
priorityDate | 2001-07-24-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 265.