摘要:
Polyether polymers such as polyetherimides are prepared by a two-step reaction. The first step is the reaction between an alkali metal salt of a dihydroxy-substituted aromatic hydrocarbon, such as bisphenol A disodium salt, and a substituted aromatic compound such as 1,3-bis[N-(4-chlorophthalimido)]benzene, the alkali metal salt being employed in an amount less than stoichiometric. The intermediate low molecular weight polymer thus produced then undergoes reaction with additional alkali metal salt. By this method, a polyether polymer of closely controlled molecular weight can be conveniently prepared.
摘要:
Aromatic polyethers are prepared by displacement polymerization reaction in the presence of a water-immiscible solvent with boiling point at atmospheric pressure of greater than 110° C. and a density ratio to water of greater than 1.1:1 at 20-25° C. The polyethers are purified by processes comprising aqueous extraction, or filtration, or a combination thereof.
摘要:
Bis(halophthalimides) such as, 3-bis[N-(4-chlorophthalimido)]benzene are prepared in slurry in an organic liquid such as o-dichlorobenzene or anisole, by a reaction at a temperature of at least 150° C. between at least one diamino compound, preferably an aromatic diamine such as m- or p-phenylenediamine, and at least one halophthalic anhydride such as 4-chlorophthalic anhydride, in the presence of an imidization catalyst such as sodium phenylphosphinate. The solids content of the reaction mixture is at least about 5% and preferably at least about 12% by weight. The product slurry may be employed directly in the preparation of polyetherimides, and similar slurries may be employed to prepare other polyether polymers.
摘要:
High yields of ester-substituted diary carbonates such as bis-methyl salicyl carbonate were obtained by the condensation of methyl salicylate with phosgene in the presence of a phase transfer catalyst (PTC) in an interfacial reaction system in which the pH of the aqueous phase was greater than 9.3. Using the method of the present invention conversions of greater than 99% were obtained whereas under standard conditions using triethylamine as the catalyst conversions were limited to 70-75% of the methyl salicylate starting material even with a 20 mole % excess of added phosgene. The optimized conditions of the of the present invention use only a slight excess of phosgene and represent an attractive route for the manufacture of bis methyl salicyl carbonate and ester-substituted diaryl carbonates generally.
摘要:
High yields of ester-substituted diary carbonates such as bis-methyl salicyl carbonate were obtained by the condensation of methyl salicylate with phosgene in the presence of a phase transfer catalyst (PTC) in an interfacial reaction system in which the pH of the aqueous phase was greater than 9.3. Using the method of the present invention conversions of greater than 99% were obtained whereas under standard conditions using triethylamine as the catalyst conversions were limited to 70-75% of the methyl salicylate starting material even with a 20 mole % excess of added phosgene. The optimized conditions of the of the present invention use only a slight excess of phosgene and represent an attractive route for the manufacture of bis methyl salicyl carbonate and ester-substituted diaryl carbonates generally.
摘要:
Aromatic polyethers are prepared by displacement polymerization reaction in the presence of a water-immiscible solvent with density ratio to water in a range of between about 0.9:1 and about 1.1:1 measured at a temperature in a range of between about 20° C. and about 25° C. The polyethers are purified by processes comprising aqueous extraction, or filtration, or a combination thereof.
摘要:
Embodiments of the invention provide for methods of producing a composition comprising a crosslinkable silane-terminated polymer having at least one crosslinkable silyl group in each molecule. The method comprises providing a polymer having at least one unsaturated group and at least one alcoholic hydroxyl group in each molecule, adding to the polymer a compound having a hydrogen-silicon bond and a crosslinkable silyl group in each molecule and a hydrosilylation catalyst to thereby carry out a hydrosilylation reaction to form a composition comprising hydrosilylated polyoxyalkylene polymers, reacting the hydrosilylated polyoxyalkylene polymers with at least one isocyanate in the presence of a first tin-free catalyst to form an isocyanate reacted hydrosilylated polymer, and optionally reacting the isocyanate reacted hydrosilylated polymer with a polyol having a nominal functionality of at least 2 to form a polyol reacted crosslinkable silane-terminated polymer.
摘要:
Embodiments of the invention provide for methods of producing a composition comprising a crosslinkable silane-terminated polymer having at least one crosslinkable silyl group in each molecule. The method comprises providing a polymer having at least one unsaturated group and at least one alcoholic hydroxyl group in each molecule, adding to the polymer a compound having a hydrogen-silicon bond and a crosslinkable silyl group in each molecule and a hydrosilylation catalyst to thereby carry out a hydrosilylation reaction to form a composition comprising hydrosilylated polyoxyalkylene polymers, reacting the hydrosilylated polyoxyalkylene polymers with at least one isocyanate in the presence of a first tin-free catalyst to form an isocyanate reacted hydrosilylated polymer, and optionally reacting the isocyanate reacted hydrosilylated polymer with a polyol having a nominal functionality of at least 2 to form a polyol reacted crosslinkable silane-terminated polymer.
摘要:
Compositions comprise phase separated polyetherimide/polyphenylene ether sulfone blends. The dispersed phase has an average cross sectional size of 0.1 to 10 micrometers. The composition retains has good hydrolytic stability and is capable of withstanding steam autoclaving at temperatures of 130 to 138° C.
摘要:
Compositions comprise phase separated polyetherimide/polyphenylene ether sulfone blends. The dispersed phase has an average cross sectional size of 0.1 to 10 micrometers. The composition retains has good hydrolytic stability and is capable of withstanding steam autoclaving at temperatures of 130 to 138° C.