Compositions and methods of making a modified polyhydroxylated polymer comprising a polyhydroxylated polymer having reversibly modified hydroxyl groups, whereby the hydroxyl groups are modified by an acid-catalyzed reaction between a polydroxylated polymer and a reagent such as acetals, aldehydes, vinyl ethers and ketones such that the modified polyhydroxylated polymers become insoluble in water but freely soluble in common organic solvents allowing for the facile preparation of acid-sensitive materials. Materials made from these polymers can be made to degrade in a pH-dependent manner. Both hydrophobic and hydrophilic cargoes were successfully loaded into particles made from the present polymers using single and double emulsion techniques, respectively. Due to its ease of preparation, processability, pH-sensitivity, and biocompatibility, of the present modified polyhydroxylated polymers should find use in numerous drug delivery applications.

This disclosure relates to silicon modified vinyl acetate ethylene copolymers and to emulsions and articles of manufacture based on the same.

This disclosure relates to silicon modified vinyl acetate ethylene copolymers and to emulsions and articles of manufacture based on the same.

The present invention provides an epoxy resin composition that is provided with flexibility to combine impact resistance and mechanical strength, while maintaining epoxy resin-specific high elastic modulus, that reduces an increase in viscosity due to mixing, and that is excellent in heat resistance, storage stability, and solvent resistance. Provided is an epoxy resin composition containing: a modified polyvinyl acetal resin having a constitutional unit with an acid-modified group; a reactive diluent; and an epoxy resin, the epoxy resin composition having a sea-island phase separated structure after being cured.

The present invention provides an epoxy resin composition that is provided with flexibility to combine impact resistance and mechanical strength, while maintaining epoxy resin-specific high elastic modulus, that reduces an increase in viscosity due to mixing, and that is excellent in heat resistance, storage stability, and solvent resistance. Provided is an epoxy resin composition containing: a modified polyvinyl acetal resin having a constitutional unit with an acid-modified group; a reactive diluent; and an epoxy resin, the epoxy resin composition having a sea-island phase separated structure after being cured.

To provide a method for producing a fluorinated polymer, in which it is possible to efficiently and easily control the molecular weight to be proper when polymerizing a perfluoromonomer having a dioxolane ring containing a polymerizable double bond in the ring skeleton, and in which the obtainable fluorinated polymer is less susceptible to a decrease in molecular weight even when contacted with a base. A method for producing a fluorinated polymer, comprising polymerizing a raw-material mixture which contains at least one of a monomer composition M11 which comprises a perfluoromonomer represented by the formula m11 and a fluorinated monomer m11H having at least some of fluorine atoms of said perfluoromonomer substituted by hydrogen atoms, and a monomer composition M12 which comprises a perfluoromonomer represented by formula m12 and a fluorinated monomer m12H having at least some of fluorine atoms of said perfluoromonomer substituted by hydrogen atoms, wherein the total amount of the fluorinated monomer mil H and the fluorinated monomer m12H is from 10 to 1,100 ppm to the total amount of the monomer composition M11 and the monomer composition M12.

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To provide a method for producing a fluorinated polymer, in which it is possible to efficiently and easily control the molecular weight to be proper when polymerizing a perfluoromonomer having a dioxolane ring containing a polymerizable double bond in the ring skeleton, and in which the obtainable fluorinated polymer is less susceptible to a decrease in molecular weight even when contacted with a base. A method for producing a fluorinated polymer, comprising polymerizing a raw-material mixture which contains at least one of a monomer composition M11 which comprises a perfluoromonomer represented by the formula m11 and a fluorinated monomer m11H having at least some of fluorine atoms of said perfluoromonomer substituted by hydrogen atoms, and a monomer composition M12 which comprises a perfluoromonomer represented by formula m12 and a fluorinated monomer m12H having at least some of fluorine atoms of said perfluoromonomer substituted by hydrogen atoms, wherein the total amount of the fluorinated monomer mil H and the fluorinated monomer m12H is from 10 to 1,100 ppm to the total amount of the monomer composition M11 and the monomer composition M12.

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[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.

[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.

To provide a method for fractionating a liquid composition, which is excellent in separability of the liquid composition. This method for fractionating a liquid composition comprises discharging, from a discharge port of a filling nozzle, a liquid composition containing a solvent and a polymer having ion exchange groups, and fractionating a predetermined amount of the liquid composition, characterized in that the temperature of the liquid composition is controlled so that the average tan 1 of the liquid composition when discharged from the discharge port of the filling nozzle becomes to be at most 1.00.