摘要:
The invention provides a polyester production process by bulk polymerization in a reactor, wherein the volume of the resulting polyester is shrunk for a release from the inner surface of the reactor, so that the polyester can be recovered in the form of a bulky mass. The invention also provides a reactor for bulk polymerization for polyester, which comprises an inner surface that enabling the resulting polyester to be released therefrom upon its volume shrinkage.
摘要:
A polyglycolic acid-based resin composition is formed by adding a relatively small amount of aromatic polyester resin to a polyglycolic acid resin. The thus-formed composition is provided with remarkably improved moisture resistance stability and hot-melt processability, and further improved stretchability, while retaining the excellent properties as represented by gas barrier property of the polyglycolic acid resin. As a result of stretching by utilizing the improved stretchability, a shaped product having an improved transparency can be obtained.
摘要:
In the production of an aliphatic polyester by ring-opening polymerization of a cyclic ester, at least a latter period of polymerization is proceeded with by way of solid-phase polymerization, and the resultant aliphatic polyester is subjected to removal of residual cyclic ester. As a result, an aliphatic polyester with a minimized content of residual monomer is obtained.
摘要:
In the production of an aliphatic polyester by ring-opening polymerization of a cyclic ester, at least a latter period of polymerization is proceeded with by way of solid-phase polymerization, and the resultant aliphatic polyester is subjected to removal of residual cyclic ester. As a result, an aliphatic polyester with a minimized content of residual monomer is obtained.
摘要:
A polyglycolic acid-based resin composition is formed by adding a relatively small amount of aromatic polyester resin to a polyglycolic acid resin. The thus-formed composition is provided with remarkably improved moisture resistance stability and hot-melt processability, and further improved stretchability, while retaining the excellent properties as represented by gas barrier property of the polyglycolic acid resin. As a result of stretching by utilizing the improved stretchability, a shaped product having an improved transparency can be obtained.
摘要:
Disclosed herein is a process for the production of an alkylene thioether-arylene thioether copolymer, which comprises copolymerizably reacting a compound having at least one alkali thiolate group and obtained by causing an alkali metal sulfide to act on a poly(arylene thioether) in a water-containing polar organic solvent so as to depolymerize the poly(arylene thioether) with a dihalogen-substituted aliphatic compound in a water-containing polar organic solvent.
摘要:
Disclosed herein are a process for the preparation of a carboxylated arylene thioether oligomer, in which an alkali metal sulfide is caused to act on a poly(arylene thioether) so as to depolymerize the poly(arylene thioether), thereby preparing an alkali thiolate-containing oligomer, and a carboxylating agent is then caused to act on the alkali thiolate-containing oligomer, thereby forming the carboxylated arylene thioether oligomer, and a process for the production of an arylene thioether copolymer, wherein the carboxylated arylene thioether oligomer alone, which has been obtained in accordance with this preparation process, or a mixture of the carboxylated oligomer in an amount of at least 50 wt. % and another carboxylic compound in an amount less than 50 wt. % is reacted with an alkylenediol or an alkylenediol and a polyester or an alkylene diol and a lactone.
摘要:
Disclosed herein are a process for the preparation of a carboxylated arylene thioether oligomer, in which an alkali metal sulfide is caused to act on a poly(arylene thioether) so as to depolymerize the poly(arylene thioether), thereby preparing an alkali thiolate-containing oligomer, and a carboxylating agent is then caused to act on the alkali thiolate-containing oligomer, thereby forming the carboxylated arylene thioether oligomer, and a process for the production of an arylene thioether copolymer, wherein the carboxylated arylene thioether oligomer alone, which has been obtained in accordance with this preparation process, or a mixture of the carboxylated oligomer in an amount of at least 50 wt. % and another carboxylic compound in an amount less than 50 wt. % is reacted with an alkylenediol or an alkylenediol and a polyester or an alkylene diol and a lactone.
摘要:
Disclosed herein are a process for the preparation of a carboxylated arylene thioether oligomer, in which an alkali metal sulfide is caused to act on a poly(arylene thioether) so as to depolymerize the poly(arylene thioether), thereby preparing an alkali thiolate-containing oligomer, and a carboxylating agent is then caused to act on the alkali thiolate-containing oligomer, thereby forming the carboxylated arylene thioether oligomer, and a process for the production of an arylene thioether copolymer, wherein the carboxylated arylene thioether oligomer alone, which has been obtained in accordance with this preparation process, or a mixture of the carboxylated oligomer in an amount of at least 50 wt. % and another carboxylic compound in an amount less than 50 wt. % is reacted with an alkylenediol or an alkylenediol and a polyester or an alkylene diol and a lactone.
摘要:
A process for producing an aliphatic polyester through ring-opening polymerization of a cyclic ester, wherein a partial polymer in a molten state is continuously introduced into a twin-screw stirring device to continuously obtain a partial polymer in a solid pulverized state, the partial polymer is subjected to solid-phase polymerization, and the resultant polymer is melt-kneaded together with a thermal stabilizer to be formed into pellets. As a result, an aliphatic polyester of a high molecular weight and with little discoloration is produced efficiently.