Polymethallyl alcohol resin composition and molding containing same

A resin composition, consisting of:

• polymethallyl alcohol (A) having a repeating structural unit represented by formula (1) in an amount of 80 to 100 mol %;
• a metal ion (B), wherein said metal ion (B) consists of at least one of an ion of sodium, an ion of potassium, an ion of calcium, and an ion of magnesium, and
• optionally component (C) in an amount greater than or equal to 0.01 μmol per 1 g of the polymethallyl alcohol (A), and the component (C) is at least one of an acid component having a pKa of 3.5 to 7.4 and an anion of the acid component, the pKa being a logarithmic value of a reciprocal of an acid dissociation constant at 25° C.,
• wherein a content of the metal ion (B) is greater than or equal to 0.5 μmol per 1 g of the polymethallyl alcohol (A) and lower than or equal to 35 μmol per 1 g of the polymethallyl alcohol (A):
• wherein the polymethallyl alcohol (A) consists of the repeating structural unit represented by formula (1) or consists of the repeating structural unit represented by formula (1) and another structural unit selected from the group consisting of methyl methacrylate, methyl acrylate, allyl alcohol, and styrene.