The present disclosure is directed to provide a polyacetal resin composition which reduces mold contaminations, formaldehyde released from molded articles, and occurrence of foreign matters in the molded articles, even when the molded articles are produced under conditions where the materials are exposed to a high temperature for long time. A polyacetal resin composition of the present disclosure contains: a polyacetal resin (A); and a semi-aromatic polyamide resin (B) which contains a dicarboxylic acid unit containing 75 mol % or more of an isophthalic acid unit, and a diamine unit containing 50 mol % or more of a diamine unit having a carbon number of 4 to 10, and has a number average molecular weight Mn of 3,000 or more and 20,000 or less.

A variety of plates for footwear are provided including a polyolefin resin. Sole structures and articles of footwear formed therefrom are also provided. Methods of making the polyolefin resin compositions, plates, sole structures, and articles of footwear are also provided. In some aspects, the polyolefin resin composition includes an effective amount of a polymeric resin modifier. The effective amount can be an amount effective to allow the resin composition to pass a flex test, and in particular to pass a flex test without significant change in abrasion loss. In some aspects, the resin composition also includes a clarifying agent to improve optical clarity of the plate. In some aspects, the plates include a textile disposed on one or both of a first side and the second side of the plate. The textile can provide for improved bonding of the plate to other components such as a chassis or an upper.

A variety of plates for footwear are provided including a polyolefin resin. Sole structures and articles of footwear formed therefrom are also provided. Methods of making the polyolefin resin compositions, plates, sole structures, and articles of footwear are also provided. In some aspects, the polyolefin resin composition includes an effective amount of a polymeric resin modifier. The effective amount can be an amount effective to allow the resin composition to pass a flex test, and in particular to pass a flex test without significant change in abrasion loss. In some aspects, the resin composition also includes a clarifying agent to improve optical clarity of the plate. In some aspects, the plates include a textile disposed on one or both of a first side and the second side of the plate. The textile can provide for improved bonding of the plate to other components such as a chassis or an upper.

A method for producing a polyacetal resin composition which allows for suppression of formaldehyde generation from a molded article to an extremely low level, and stable suppression of mold deposits during molding. The polyacetal resin composition contains: 100 parts by mass of a polyacetal polymer (A); 0.01 to 0.50 parts by mass of an aliphatic carboxylic acid hydrazide (B); 0.001 to 0.50 parts by mass of a hydantoin compound having two hydrazinocarbonylalkyl groups (C); and 0.001 to 0.30 parts by mass of an alkaline earth metal salt of aliphatic carboxylic acid (D), wherein the total amount of the components (B) and (C) with respect to 100 parts by mass of the polyacetal polymer (A) is 0.03 to 0.55 parts by mass, and wherein the polyacetal polymer (A) is a polyacetal copolymer obtained by copolymerizing trioxane as a principal monomer (a) with a cyclic ether having at least one carbon-carbon bond as a comonomer (b) using a heteropolyacid represented by general formula (1) as a polymerization catalyst (c) to obtain a reaction product, and subsequently adding a carbonate of an alkali metal element or alkaline earth metal element (d) to the reaction product to deactivate the polymerization catalyst (c).

A method for producing a polyacetal resin composition which allows for suppression of formaldehyde generation from a molded article to an extremely low level, and stable suppression of mold deposits during molding. The polyacetal resin composition contains: 100 parts by mass of a polyacetal polymer (A); 0.01 to 0.50 parts by mass of an aliphatic carboxylic acid hydrazide (B); 0.001 to 0.50 parts by mass of a hydantoin compound having two hydrazinocarbonylalkyl groups (C); and 0.001 to 0.30 parts by mass of an alkaline earth metal salt of aliphatic carboxylic acid (D), wherein the total amount of the components (B) and (C) with respect to 100 parts by mass of the polyacetal polymer (A) is 0.03 to 0.55 parts by mass, and wherein the polyacetal polymer (A) is a polyacetal copolymer obtained by copolymerizing trioxane as a principal monomer (a) with a cyclic ether having at least one carbon-carbon bond as a comonomer (b) using a heteropolyacid represented by general formula (1) as a polymerization catalyst (c) to obtain a reaction product, and subsequently adding a carbonate of an alkali metal element or alkaline earth metal element (d) to the reaction product to deactivate the polymerization catalyst (c).

A method for producing a polyacetal resin composition which allows for suppression of formaldehyde generation from a molded article to an extremely low level, and stable suppression of mold deposits during molding. The polyacetal resin composition contains: 100 parts by mass of a polyacetal polymer (A); 0.01 to 0.50 parts by mass of an aliphatic carboxylic acid hydrazide (B); 0.001 to 0.50 parts by mass of a hydantoin compound having two hydrazinocarbonylalkyl groups (C); and 0.001 to 0.30 parts by mass of an alkaline earth metal salt of aliphatic carboxylic acid (D), wherein the total amount of the components (B) and (C) with respect to 100 parts by mass of the polyacetal polymer (A) is 0.03 to 0.55 parts by mass, and wherein the polyacetal polymer (A) is a polyacetal copolymer obtained by copolymerizing trioxane as a principal monomer (a) with a cyclic ether having at least one carbon-carbon bond as a comonomer (b) using a heteropolyacid represented by general formula (1) as a polymerization catalyst (c) to obtain a reaction product, and subsequently adding a carbonate of an alkali metal element or alkaline earth metal element (d) to the reaction product to deactivate the polymerization catalyst (c).

A polyacetal resin composition which exhibits resistance to hot water, and contains 100 parts by mass of a polyacetal resin, 1 to 100 parts by mass, inclusive, of glass fibers subjected to a surface treatment with a blocked isocyanate compound and an aminosilane coupling agent, and 0.001 to 1.0 parts by mass, inclusive, of boric acid.

A polyacetal resin composition which exhibits resistance to hot water, and contains 100 parts by mass of a polyacetal resin, 1 to 100 parts by mass, inclusive, of glass fibers subjected to a surface treatment with a blocked isocyanate compound and an aminosilane coupling agent, and 0.001 to 1.0 parts by mass, inclusive, of boric acid.

A resin powder for solid freeform fabrication, having a ratio (Mv/Mn) of 2.00 or less, where Mv represents a volume average particle diameter and Mn represents a number average particle diameter and a ratio of melt mass-flow rate B to melt mass-flow rate A of greater than 0.80 to 1.20, wherein the melt mass-flow rate A and the melt mass-flow rate B are respectively measured at 15 degrees C. higher than the melting point under a load of 2.16 kg according to JIS K7210 format before and after the resin powder is maintained at a temperature 15 degrees C. lower than the melting point under a pressure of 0.1 kPa for four hours.

A resin powder for solid freeform fabrication, having a ratio (Mv/Mn) of 2.00 or less, where Mv represents a volume average particle diameter and Mn represents a number average particle diameter and a ratio of melt mass-flow rate B to melt mass-flow rate A of greater than 0.80 to 1.20, wherein the melt mass-flow rate A and the melt mass-flow rate B are respectively measured at 15 degrees C. higher than the melting point under a load of 2.16 kg according to JIS K7210 format before and after the resin powder is maintained at a temperature 15 degrees C. lower than the melting point under a pressure of 0.1 kPa for four hours.