摘要:
A process for the preparation of a polycarbonate comprising reacting a diaryl carbonate with a bisphenol to produce a polycarbonate and a phenol, regenerating the diaryl carbonate by reacting the phenol byproduct with a carbonyl halide, and optionally recycling the hydrogen halide using a metal Redox captive halogen swing reactor system.
摘要:
Method and apparatus for determining various molecular weight distribution parameters by concurrent measurement of hydrodynamic volume, specific viscosity and mass. Essentially concurrent viscosity and mass detectors are described, as are improved methods for viscosity detection, which together provide substantially improved results.
摘要:
A process for the preparation of an aromatic carbonate or polycarbonate from a phenol or bisphenol, methanol, carbon monoxide and oxygen comprising the steps of 1) reacting phenol or bisphenol with acetic anhydride to form (bis)phenyl acetate; 2) reacting dimethyl carbonate with (bis)phenyl acetate from step 1 to produce a phenyl carbonate or polycarbonate and methyl acetate; and 3) reacting the methyl acetate with carbon monoxide to produce acetic anhydride for use in step 1. In a desirable embodiment the dimethyl carbonate may also be prepared by reaction of methanol, carbon monoxide and oxygen.
摘要:
A process for the preparation of a polycarbonate comprising reacting a diaryl carbonate with a bisphenol to produce a polycarbonate and a phenol, regenerating the diaryl carbonate by reacting the phenol byproduct with a carbonyl halide, and optionally recycling the hydrogen halide using a metal Redox captive halogen swing reactor system.
摘要:
Aromatic carbonates useful for the preparation of high molecular weight polycarbonate resins are prepared by reacting methanol, carbon monoxide and oxygen to prepare dimethyl carbonate; reacting a methyl silyl ether with a phenol or bisphenol to prepare an aryl silyl ether, and reacting the dimethyl carbonate and aryl silyl ether to prepare an aromatic carbonate.