摘要:
Macrocyclic oligomers, including polycarbonates, polyesters, polyamides, polyimides, polyetherketones and polyethersulfones, are conveniently prepared from various spiro(bis)indane compounds, especially the 6,6'-difunctional 3,3',3'-tetramethylspiro(bis)indanes. The macrocyclic oligomers may be conveniently converted to linear polymers.
摘要:
Macrocyclic oligomers, including polycarbonates, polyesters, polyamides, polyimides, polyetherketones and polyethersulfones, are conveniently prepared from various spiro(bis)indane compounds, especially the 6,6'-difunctional 3,3',3'-tetramethylspiro(bis)indanes. The macrocyclic oligomers may be conveniently converted to linear polymers.
摘要:
Cyclic heterocarbonates containing linkages such as ester, urethane, imide, ether sulfone, ether ketone or amide may be prepared from the corresponding bishaloformates. They may be converted to linear copolycarbonates.
摘要:
Cyclic polycarbonate (or thiol analog) oligomer mixtures are prepared by the reaction of bishaloformates or their thio analogs, or mixtures thereof with dihydroxy or dimercapto compounds, with alkali metal hydroxides and various amines. The oligomer mixtures may be converted to polycarbonates or their thiol analogs by a method which is particularly adaptable to integration with polycarbonate processing operations. Polymerization may be conducted simultaneously with molding, extrusion and the like. The oligomer mixtures are adaptable to the preparation of filled prepregs.
摘要:
A process which comprises reacting interfacially a dihydric phenol, a carbonate precursor and a prior prepared salt of an aliphatic alpha omega dicarboxylic acid having from 8 to about 20 carbon atoms thereby producing a copolyestercarbonate.
摘要:
The molar concentration of chloroformate in an organic chloroformate solution is determined by adding an excess of a monohydroxyaromatic compound, water and a catalytic amount of a 4-dialkylaminopyridine such as 4-dimethylaminopyridine, titrating with aqueous base and taking as the end point the volume of base which achieves complete conversation of chloroformate groups to monoaromatic carbonate groups, as shown by a rapid rise in the pH of the aqueous phase of more than two points to a value in the range of 7-9. This method is particularly applicable to the determination of bischloroformate molar concentration in systems to be converted to cyclic polycarbonate oligomers. Conversion may be effected by condensation in the presence of a trialkylamine and aqueous base in the amount of about 3 moles per mole of bischloroformate.
摘要:
A method is provided for making flame retardant polycarbonates by phosgenating a mixture of bisphenols having up to about 50 mole % of tetrahalobisphenols, such as tetrabromobisphenols. There is employed a mixture of a phase transfer catalyst and a tertiary organic amine to provide high molecular weight copolymer without excessive phosgene usage.
摘要:
Ester polyphenols such as the tris(bisphenol A) ester of trimellitic acid are prepared by the reaction of the corresponding aromatic poly(acyl halide) with a dihydroxyaromatic compound such as bisphenol A. They may be employed in the preparation of branched polycarbonates via chloroformate oligomer compositions.
摘要:
Macrocyclic polyarylate oligomers containing a mixture of isophthalate and terephthalate moieties are prepared by reaction of a mixture of isophthaloyl and terephthaloyl chloride with one or more bisphenols under specific reaction conditions. They are characterized by a reduced degree of crystallinity and therefore lower processing temperatures than the corresponding isophthalate oligomers.
摘要:
Polycarbonates containing aliphatic dicarboxylic ester groups, and having glass transition temperatures and processing temperatures lower than the corresponding homopolycarbonates are prepared via an intermediate which is in turn prepared from a dihydroxyaromatic compound and a C.sub.4-6 aliphatic dicarboxylic acid anhydride, preferably succinic anhydride. Phosgenation of said intermediate produces the desired soft segment polycarbonate.