A polymer composition that comprises from about 50 wt. % to about 90 wt. % of a polymer matrix and from about 10 wt. % to about 50 wt. % of silica particles is provided. The polymer matrix includes a liquid crystalline polymer containing repeating units derived from naphthenic hydroxycarboxylic and/or dicarboxylic acids in an amount of about 15 mol. % or less of the polymer. The silica particles have a median particle size of about 4 micrometers or less. The polymer composition exhibits a tensile modulus of 11,000 MPa or more as determined in accordance with ISO Test No. 527:2019.

A polymer composition that comprises from about 50 wt. % to about 90 wt. % of a polymer matrix and from about 10 wt. % to about 50 wt. % of silica particles is provided. The polymer matrix includes a liquid crystalline polymer containing repeating units derived from naphthenic hydroxycarboxylic and/or dicarboxylic acids in an amount of about 15 mol. % or less of the polymer. The silica particles have a median particle size of about 4 micrometers or less. The polymer composition exhibits a tensile modulus of 11,000 MPa or more as determined in accordance with ISO Test No. 527:2019.

Biodegradable resin particles including a polyhydroxy alkanoate. In the biodegradable resin particles, an amount of a Ca component present in the particles is 10 to 10,000 ppm, the biodegradable resin particles have a volume average particle diameter of 2 to 50 μm, the biodegradable resin particles have a BET specific surface area of 0.8 to 10 m.sup.2/g, and the biodegradable resin particles have a linseed oil absorption of 50 to 300 ml/100 g. The resin particles of the present invention can be suitably used by being included in an external preparation, such as a cosmetic or a quasi-drug.

The present invention provides an aromatic polyester having several operative functional groups and a method for producing same. An aromatic polyester comprising a polycarboxylic acid component and a polyhydric alcohol component as a copolymerization component, wherein the aromatic polyester comprises a polycarboxylic acid component having an operative functional group by 50 mol % or more when a total amount of the polycarboxylic acid component is taken as 100 mol %, and the aromatic polyester comprises an aromatic polyhydric alcohol component by 50 mol % or more when a total amount of the polyhydric alcohol component is taken as 100 mol %.

The object of the present invention is to provide a production method which makes it possible to obtain a PHA with a simple operation. The object can be attained by providing a method for producing a polyhydroxyalkanoate, the method including the steps of: (a) preparing an aqueous polyhydroxyalkanoate suspension having a pH of not more than 7; and (b) heating the aqueous polyhydroxyalkanoate suspension, prepared in the step (a), at a temperature set at 80° C. to 300° C. in a twin screw extruder so as to aggregate a polyhydroxyalkanoate.

An object of an embodiment of the present invention is to provide a biodegradable polyester solution that exhibits good solubility in a halogen-free organic solvent and that has sufficient adhesive strength even when aged for a short time. The object is achieved by providing a biodegradable polyester solution containing a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymer and a solvent, the poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymer having an average content of 16 mol % or more 3-hydroxyhexanoate.

An object of an embodiment of the present invention is to provide a biodegradable polyester solution that exhibits good solubility in a halogen-free organic solvent and that has sufficient adhesive strength even when aged for a short time. The object is achieved by providing a biodegradable polyester solution containing a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymer and a solvent, the poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymer having an average content of 16 mol % or more 3-hydroxyhexanoate.

A copolymer comprising: a hydroxycarboxylic acid (A) having a hydroxy group only at a 2-position; and a hydroxycarboxylic acid (B) having a hydroxy group at a position other than a 2-position, and having a homopolymer segment composed of one hydroxycarboxylic acid selected from the group consisting of the hydroxycarboxylic acid (A) and the hydroxycarboxylic acid (B), and a copolymer segment containing at least two hydroxycarboxylic acids selected from the group consisting of the hydroxycarboxylic acid (A) and the hydroxycarboxylic acid (B).

A copolymer comprising: a hydroxycarboxylic acid (A) having a hydroxy group only at a 2-position; and a hydroxycarboxylic acid (B) having a hydroxy group at a position other than a 2-position, and having a homopolymer segment composed of one hydroxycarboxylic acid selected from the group consisting of the hydroxycarboxylic acid (A) and the hydroxycarboxylic acid (B), and a copolymer segment containing at least two hydroxycarboxylic acids selected from the group consisting of the hydroxycarboxylic acid (A) and the hydroxycarboxylic acid (B).

An objective of the present invention is to provide a production method that enables PHA (e.g. PHA powder) to be produced with high productivity. The above is achieved by providing: a method for producing a polyhydroxyalkanoate, including the steps of (a) preparing an aqueous suspension that contains a polyhydroxyalkanoate and an alkylene oxide-based dispersing agent and has a pH of not more than 7 and (b) spray-drying the aqueous suspension prepared in the step (a); and the like.