Abstract: The present invention is a hydrogenated cycloolefin ring-opening polymer comprising a repeating unit derived from tetracyclododecene, and a repeating unit derived from an additional norbornene-based monomer, the hydrogenated cycloolefin ring-opening polymer having a racemo diad ratio of 65% or more with respect to the repeating unit derived from tetracyclododecene, the hydrogenated cycloolefin ring-opening polymer having a weight average molecular weight (Mw) of 10,000 to 40,000, and a resin formed article obtained by forming the hydrogenated cycloolefin ring-opening polymer having a glass transition temperature of 140 to 165° C., a melt flow rate of 8 g/10 min or more as measured at a temperature of 280° C. under a load of 21.18 N, and a flexural strength of 60 MPa or more as measured by a flexural test at a test speed of 2 mm/min, and a resin formed article, and an optical member.

Abstract: The present invention provides a resin composition comprising an alicyclic-structure-containing polymer and a polyglyceride-based additive, wherein the polyglyceride-based additive includes one or a plurality of polyglyceride compounds, the polyglyceride-based additive has a hydroxyl value of 320 to 700 mgKOH/g, and the content of the polyglyceride-based additive is 0.2 to 2.0 parts by weight based on 100 parts by weight of the alicyclic-structure-containing polymer. The present invention also provides a resin formed article obtained by forming the resin composition. According to the present invention, a resin composition which hardly whitens even under a hot and humid environment and hardly causes a bleed-out phenomenon of additives, and a resin formed article obtained by forming the resin composition are provided.

Abstract: The invention is a resin composition comprising an alicyclic-structure-containing polymer, a hindered-phenol-based antioxidant and a hindered amine compound, wherein the hindered-phenol-based antioxidant is a compound having a group represented by the specific formula, the hindered amine compound is a compound having a group represented by the specific formula in its molecule, a content of the hindered-phenol-based antioxidant is 0.1 to 2.0 parts by weight based on 100 parts by weight of the alicyclic-structure-containing polymer, and a content of the hindered amine compound is more than 0 to 1.0 part by weight based on 100 parts by weight of the alicyclic-structure-containing polymer, and a resin formed article, and an optical member. One aspect of the invention provides a resin composition which is hardly burned during forming, has excellent long-term thermal yellowing resistance and also suppresses adhesion of foreign matters due to charge, a resin formed article, and an optical member.

Abstract: The present invention is a hydrogenated cycloolefin ring-opening polymer comprising a repeating unit derived from tetracyclododecene, and a repeating unit derived from an additional norbornene-based monomer, the hydrogenated cycloolefin ring-opening polymer having a racemo diad ratio of 65% or more with respect to the repeating unit derived from tetracyclododecene, the hydrogenated cycloolefin ring-opening polymer having a weight average molecular weight (Mw) of 10,000 to 40,000, and a resin formed article obtained by forming the hydrogenated cycloolefin ring-opening polymer having a glass transition temperature of 140 to 165° C., a melt flow rate of 8 g/10 min or more as measured at a temperature of 280° C. under a load of 21.18 N, and a flexural strength of 60 MPa or more as measured by a flexural test at a test speed of 2 mm/min, and a resin formed article, and an optical member.