[Problem to be Solved] To Provide a method for producing an acid-decomposable polymer having a reduced metal ion content, which suppresses decomposition and deprotection of the acid-decomposable polymer. [Means to Solve the Problem] The method for producing an acid-decomposable polymer according to the present invention comprises the steps of: preparing a polymer solution comprising an acid-decomposable polymer; washing an acidic cation exchanger with an organic solvent until the water content in the organic solvent discharged from the acidic cation exchanger falls to 400 ppm or less; and passing the polymer solution through the washed acidic cation exchanger to reduce the metal ion content of the polymer.

The present invention relates to a continuous process for purifying a chain-extended aliphatic polyester constructed from aliphatic dicarboxylic acids and aliphatic diols in a degassing apparatus, wherein the crude polyester is degassed for 3 to 30 minutes 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 an entraining agent.

The present invention relates to a continuous process for purifying a chain-extended aliphatic polyester constructed from aliphatic dicarboxylic acids and aliphatic diols in a degassing apparatus, wherein the crude polyester is degassed for 3 to 30 minutes 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 an entraining agent.

A PLG copolymer material, termed a PLG(p) copolymer material, adapted for use in a controlled release formulation for a bioactive material is provided, wherein the formulation exhibits a reduced “initial burst” effect when introduced into the tissue of a patient in need thereof. A method of preparation of the PLG copolymer material is also provided, as are methods of use.

A PLG copolymer material, termed a PLG(p) copolymer material, adapted for use in a controlled release formulation for a bioactive material is provided, wherein the formulation exhibits a reduced “initial burst” effect when introduced into the tissue of a patient in need thereof. A method of preparation of the PLG copolymer material is also provided, as are methods of use.

The present invention relates to an amphiphilic block copolymer composition which provides enhanced stability to a micelle formed by an amphiphilic block copolymer in an aqueous phase.

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. ##STR00001##

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. ##STR00001##

Provided a method for separating PHA and PHA prepared therefrom. The method comprises the following steps: subjecting a PHA fermentation broth to solid-liquid separation to obtain a thallus precipitate; breaking cell walls of the thallus precipitate, and subjecting obtained wall-broken products to a plate and frame filtration to obtain PHA; a filter cloth for the plate and frame filtration is pre-coated with a PHA layer. The method adopts a plate and frame separation to replace the traditional centrifugal separation to prepare PHA, and the PHA layer is pre-coated on the filter cloth for the plate and frame filtration, thereby overcome the defects in the prior art such as high cost and operational difficulty caused by adopting multiple centrifugal separations; in addition, the method of the present disclosure also exhibits the advantages of high recovery rate of PHA and high purity of the prepared PHA product.

Provided a method for separating PHA and PHA prepared therefrom. The method comprises the following steps: subjecting a PHA fermentation broth to solid-liquid separation to obtain a thallus precipitate; breaking cell walls of the thallus precipitate, and subjecting obtained wall-broken products to a plate and frame filtration to obtain PHA; a filter cloth for the plate and frame filtration is pre-coated with a PHA layer. The method adopts a plate and frame separation to replace the traditional centrifugal separation to prepare PHA, and the PHA layer is pre-coated on the filter cloth for the plate and frame filtration, thereby overcome the defects in the prior art such as high cost and operational difficulty caused by adopting multiple centrifugal separations; in addition, the method of the present disclosure also exhibits the advantages of high recovery rate of PHA and high purity of the prepared PHA product.