An object of the present invention is to provide a method for producing PHA capable of providing PHA (for example, a PHA powder) having excellent thermal stability with high productivity. The present invention is a method for producing polyhydroxyalkanoic acid, the method including a step (a) and a step (b) below: step (a) of preparing an aqueous suspension liquid containing polyhydroxyalkanoic acid and polyvinyl alcohol and having a pH of 7 or less; and step (b) of spray-drying the aqueous suspension liquid prepared in the step (a).

The present disclosure provides a process of recovering sulfopolyester comprising reduced impurity. Sulfopolyester is recovered from a composite material comprising water-dispersible sulfopolyester polymer and at least one non-water-dispersible polymer. The process includes washing the composite material comprising water-dispersible sulfopolyester with a solvent composition. The recovered sulfopolyester can be generated as a concentrated aqueous dispersion, a polymer melt, or a sulfopolyester solid.

The present disclosure provides a process of recovering sulfopolyester comprising reduced impurity. Sulfopolyester is recovered from a composite material comprising water-dispersible sulfopolyester polymer and at least one non-water-dispersible polymer. The process includes washing the composite material comprising water-dispersible sulfopolyester with a solvent composition. The recovered sulfopolyester can be generated as a concentrated aqueous dispersion, a polymer melt, or a sulfopolyester solid.

The present disclosure provides a process of recovering sulfopolyester comprising reduced impurity. Sulfopolyester is recovered from a composite material comprising water-dispersible sulfopolyester polymer and at least one non-water-dispersible polymer. The process includes washing the composite material comprising water-dispersible sulfopolyester with a solvent composition. The recovered sulfopolyester can be generated as a concentrated aqueous dispersion, a polymer melt, or a sulfopolyester solid.

The invention relates to a continuous process for producing an aliphatic polyester constructed from aliphatic dicarboxylic acids and aliphatic diols comprising the steps of a) esterification, b) polycondensation and optionally c) chain extension, characterized in that during step b) in which the polycondenser functions as a degassing apparatus (B) and/or b′) after the polycondensation in an additional degassing apparatus (B′) the crude polyester is degassed at a pressure of 0.01 to 5 mbar in the presence of 1% to 7% by weight, based on the total weight of the crude polyester of water, introduced into the gas space of the degassing apparatus B and/or B′ as an entraining agent.

The invention relates to a continuous process for producing an aliphatic polyester constructed from aliphatic dicarboxylic acids and aliphatic diols comprising the steps of a) esterification, b) polycondensation and optionally c) chain extension, characterized in that during step b) in which the polycondenser functions as a degassing apparatus (B) and/or b′) after the polycondensation in an additional degassing apparatus (B′) the crude polyester is degassed at a pressure of 0.01 to 5 mbar in the presence of 1% to 7% by weight, based on the total weight of the crude polyester of water, introduced into the gas space of the degassing apparatus B and/or B′ as an entraining agent.

This invention relates to the synthesis of multi-block bioresorbable polymers bearing hard and soft polymeric segments. The invention further relates to bioresorbable polymers for shape memory properties. The invention also relates to the use of such polymers as bone filler, vascular closure devices, hemostasis device, aneurysms, mastectomy devices and stent applications. The invention relates also to the use of such polymers for applications in fast degradation applications and 3D printing. The invention also relates to the use of such polymers as drug delivery platforms applications.

This invention relates to the synthesis of multi-block bioresorbable polymers bearing hard and soft polymeric segments. The invention further relates to bioresorbable polymers for shape memory properties. The invention also relates to the use of such polymers as bone filler, vascular closure devices, hemostasis device, aneurysms, mastectomy devices and stent applications. The invention relates also to the use of such polymers for applications in fast degradation applications and 3D printing. The invention also relates to the use of such polymers as drug delivery platforms applications.

The present invention relates to an amphiphilic block copolymer represented by formula I, a preparation method thereof, and a nanomicelle drug delivery system formed from the copolymer and a poorly soluble drug. The amphiphilic block copolymer includes a hydrophilic chain segment, a hydrophobic chain segment, and a linker for linking the hydrophilic chain segment to the hydrophobic chain segment. The linker contains an unsaturated structure, which can enhance the interaction between the poorly soluble drug and the copolymer to improve the drug loading ability and stability of the nanomicelle. The invention also relates to a nanomicelle drug-loading system, a preparation method thereof, and the use of the nanomicelle drug-loading system for preparing medicines for treating tumors, inflammation, diabetes, central nervous system diseases, cardiovascular diseases, and psychological disorders.

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The present invention relates to an amphiphilic block copolymer represented by formula I, a preparation method thereof, and a nanomicelle drug delivery system formed from the copolymer and a poorly soluble drug. The amphiphilic block copolymer includes a hydrophilic chain segment, a hydrophobic chain segment, and a linker for linking the hydrophilic chain segment to the hydrophobic chain segment. The linker contains an unsaturated structure, which can enhance the interaction between the poorly soluble drug and the copolymer to improve the drug loading ability and stability of the nanomicelle. The invention also relates to a nanomicelle drug-loading system, a preparation method thereof, and the use of the nanomicelle drug-loading system for preparing medicines for treating tumors, inflammation, diabetes, central nervous system diseases, cardiovascular diseases, and psychological disorders.

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