A polyoxymethylene (POM) resin composition which is used for a resin molded article having a superior sliding characteristic. The POM resin composition contains: (A) 100 parts by mass of a POM resin; (B) 0.01-1 parts by mass of a hindered phenolic antioxidant; (C) 0.05-1 parts by mass of a nitrogen-containing compound; (D) 0.5-10 parts by mass of a modified olefin polymer; (E) 0.01-5 parts by mass of an alkylene glycol polymer; (F) 0.1-20 parts by mass of calcium carbonate; (G) 0.1-10 parts by mass of a partial ester of a polyhydric alcohol; and (H) 0.1-10 parts by mass of an a-olefin oligomer. An ISO tensile test piece, which is obtained by injection molding at a die temperature of 90° C. and a cylinder temperature of 200° C., is crushed, Soxhlet extraction is performed for 3 hours at 70° C. using methanol, and the alkylene glycol polymer is measured. The weight of the alkylene glycol polymer is 0.001 wt % or less relative to 100 wt % of the test piece.

The resin molded article of the present invention comprises (B) 0.1 to 5 parts by mass of a sliding agent having a weight average molecular weight of 10,000 or less, and (C) 0.01 to 3 parts by mass of a coloring agent, based on (A) 100 parts by mass of a polyacetal resin, wherein a relative element concentration ratio between carbon and oxygen on a surface thereof [C/O] (atomic %) is 1.01 to 2.50.

The resin molded article of the present invention comprises (B) 0.1 to 5 parts by mass of a sliding agent having a weight average molecular weight of 10,000 or less, and (C) 0.01 to 3 parts by mass of a coloring agent, based on (A) 100 parts by mass of a polyacetal resin, wherein a relative element concentration ratio between carbon and oxygen on a surface thereof [C/O] (atomic %) is 1.01 to 2.50.

The resin molded article of the present invention comprises (B) 0.1 to 5 parts by mass of a sliding agent having a weight average molecular weight of 10,000 or less, and (C) 0.01 to 3 parts by mass of a coloring agent, based on (A) 100 parts by mass of a polyacetal resin, wherein a relative element concentration ratio between carbon and oxygen on a surface thereof [C/O] (atomic %) is 1.01 to 2.50.

The present disclosure is directed to a process for producing a polyoxymethylene polymer or paraformaldehyde in an environmentally friendly and sustainable manner. The polyoxymethylene polymer or paraformaldehyde can be produced so as to be carbon neutral or even carbon negative. In one aspect, the polyoxymethylene polymer or paraformaldehyde is formed from a biogas or from a recycled gas. The biogas and the recycled gas are used to produce the components needed to form the polymer.

The present disclosure is directed to a process for producing a polyoxymethylene polymer or paraformaldehyde in an environmentally friendly and sustainable manner. The polyoxymethylene polymer or paraformaldehyde can be produced so as to be carbon neutral or even carbon negative. In one aspect, the polyoxymethylene polymer or paraformaldehyde is formed from a biogas or from a recycled gas. The biogas and the recycled gas are used to produce the components needed to form the polymer.

A polymer composition is disclosed containing a coupling agent and an impact modifier that renders the composition resistant to ultraviolet light degradation. The polymer composition contains an aliphatic coupling agent, an aliphatic impact modifier, or both an aliphatic coupling agent and an aliphatic impact modifier. The polymer composition is well suited to producing molded articles, especially articles that will later be exposed to substantial amounts of ultraviolet light. For example, molded articles made according to the present disclosure are well suited for use on the interior of vehicles where the parts are not only exposed to ultraviolet light, but are also exposed to repeated thermal cycles.

A polymer composition is disclosed containing a coupling agent and an impact modifier that renders the composition resistant to ultraviolet light degradation. The polymer composition contains an aliphatic coupling agent, an aliphatic impact modifier, or both an aliphatic coupling agent and an aliphatic impact modifier. The polymer composition is well suited to producing molded articles, especially articles that will later be exposed to substantial amounts of ultraviolet light. For example, molded articles made according to the present disclosure are well suited for use on the interior of vehicles where the parts are not only exposed to ultraviolet light, but are also exposed to repeated thermal cycles.

A polymer composition is disclosed containing a coupling agent and an impact modifier that renders the composition resistant to ultraviolet light degradation. The polymer composition contains an aliphatic coupling agent, an aliphatic impact modifier, or both an aliphatic coupling agent and an aliphatic impact modifier. The polymer composition is well suited to producing molded articles, especially articles that will later be exposed to substantial amounts of ultraviolet light. For example, molded articles made according to the present disclosure are well suited for use on the interior of vehicles where the parts are not only exposed to ultraviolet light, but are also exposed to repeated thermal cycles.

A gear is provided that has excellent continuous moldability for practical use, and both high slidability and high durability. The provided gear is a molded resin constructed of a resin composition comprising a thermoplastic resin (A) and cellulose nanofibers (B) with an average fiber diameter of 1000 nm or smaller, and having a number average molecular weight of the thermoplastic resin (A) in the range of 10,000 to 150,000, wherein a sliding surface of the gear with another gear teeth has an arithmetic mean surface roughness Sa of 3.0 μm or lower.