This invention relates a wax inhibitor for hydrocarbon oils comprising an esterified copolymer having repeating structural units derived from an esterified ethylenically unsaturated dicarboxylic acid and α-olefins having at least 18 carbon atoms, whereof at least 3 mol-% of the α-olefins have 30 or more carbon atoms, and wherein the ethylenically unsaturated dicarboxylic acid has been esterified with a mixture of alcohols comprising i) 70 to 97 mol-% of a saturated fatty alcohol having 18 to 24 carbon atoms and ii) 3 to 30 mol-% of an unsaturated alcohol having 16 to 24 carbon atoms.

A method for the production of functionalized partially hydrolyzed polyvinyl acetate comprising vinyl alcohol, vinylacetate and functionalized vinyl alcohol units by reacting in a melt a partially hydrolyzed polyvinyl acetate as component A with a reactive compound carrying at least one ethylenically unsaturated group and at least one reactive group reactive with hydroxyl or acetate groups as component B, in the presence of at least one stabilizer as component C and in the presence of at least one catalyst selected from the group consisting of tertiary amines and nitrogen-containing heterocycles as component D, the method comprising the steps: feeding the components into a mixing device capable of heating, melting and mixing components A, B, C and D, heating, melting and mixing components A, B, C and D in the device to give a melt and reacting components A and B in the melt.

A method for the production of functionalized partially hydrolyzed polyvinyl acetate comprising vinyl alcohol, vinylacetate and functionalized vinyl alcohol units by reacting in a melt a partially hydrolyzed polyvinyl acetate as component A with a reactive compound carrying at least one ethylenically unsaturated group and at least one reactive group reactive with hydroxyl or acetate groups as component B, in the presence of at least one stabilizer as component C and in the presence of at least one catalyst selected from the group consisting of tertiary amines and nitrogen-containing heterocycles as component D, the method comprising the steps: feeding the components into a mixing device capable of heating, melting and mixing components A, B, C and D, heating, melting and mixing components A, B, C and D in the device to give a melt and reacting components A and B in the melt.

A method for the production of functionalized partially hydrolyzed polyvinyl acetate comprising vinyl alcohol, vinylacetate and functionalized vinyl alcohol units by reacting in a melt a partially hydrolyzed polyvinyl acetate as component A with a reactive compound carrying at least one ethylenically unsaturated group and at least one reactive group reactive with hydroxyl or acetate groups as component B, in the presence of at least one stabilizer as component C and in the presence of at least one catalyst selected from the group consisting of tertiary amines and nitrogen-containing heterocycles as component D, the method comprising the steps: feeding the components into a mixing device capable of heating, melting and mixing components A, B, C and D, heating, melting and mixing components A, B, C and D in the device to give a melt and reacting components A and B in the melt.

Provided are a polymer composition capable of achieving both thermal stability and thermal deterioration-resistant characteristics in a well-balanced manner, and a molded article and an optical member each containing the polymer composition. A polymer composition contains: a polymer including a structural unit derived from a (meth)acrylate and a structural unit derived from (meth)acrylic acid; and at least one compound (A) selected from the group consisting of 4-tert-butylcatechol, 6-tert-butyl-2,4-xylenol, paramethoxyphenol, hydroquinone, 2,2,6,6-tetramethylpiperidinyl-1-oxile, 4-hydroxy-2,2,6,6-tetramethylpiperidinyl-1-oxile, and triphenyl verdazyl. The content of compound (A) is 1 ppm by mass to 10 ppm by mass.

Provided are a polymer composition capable of achieving both thermal stability and thermal deterioration-resistant characteristics in a well-balanced manner, and a molded article and an optical member each containing the polymer composition. A polymer composition contains: a polymer including a structural unit derived from a (meth)acrylate and a structural unit derived from (meth)acrylic acid; and at least one compound (A) selected from the group consisting of 4-tert-butylcatechol, 6-tert-butyl-2,4-xylenol, paramethoxyphenol, hydroquinone, 2,2,6,6-tetramethylpiperidinyl-1-oxile, 4-hydroxy-2,2,6,6-tetramethylpiperidinyl-1-oxile, and triphenyl verdazyl. The content of compound (A) is 1 ppm by mass to 10 ppm by mass.

A binder including a metal salt of a graft copolymer, which is a polymerization product of polyvinyl alcohol, an ethylenically unsaturated carboxylic acid, and a polymerizable monomer having a long-chain alkyl group.

A binder including a metal salt of a graft copolymer, which is a polymerization product of polyvinyl alcohol, an ethylenically unsaturated carboxylic acid, and a polymerizable monomer having a long-chain alkyl group.

The invention relates to particles with an average particle size of 300 to 1000 μm, comprising a modified polyvinyl alcohol having vinyl alcohol units and structural units represented by formula (1), wherein a content of the vinyl alcohol units is 60 to 90 mol % based on the total structural units: ##STR00001## wherein R.sup.1 represents a hydrogen atom or a methyl group. Thus, the present invention provides particles containing a modified polyvinyl alcohol having high water solubility and high affinity for a photosensitive monomer, which are highly photosensitive.

The invention relates to particles with an average particle size of 300 to 1000 μm, comprising a modified polyvinyl alcohol having vinyl alcohol units and structural units represented by formula (1), wherein a content of the vinyl alcohol units is 60 to 90 mol % based on the total structural units: ##STR00001## wherein R.sup.1 represents a hydrogen atom or a methyl group. Thus, the present invention provides particles containing a modified polyvinyl alcohol having high water solubility and high affinity for a photosensitive monomer, which are highly photosensitive.