Provided is a polyfunctional vinyl aromatic copolymer having reactivity and solubility that can be used for manufacturing a copolymer rubber and a copolymer rubber material having processability, strength and homogeneity obtained therefrom. The polyfunctional vinyl aromatic copolymer includes: 0.5 mol % or more and 40 mol % or less of a structural unit (a) derived from a divinyl aromatic compound and 60 mol % or more and 99.5 mol % or less of a structural unit (b) derived from a monovinyl aromatic compound, in which at least some of the structural units (a) are a crosslinked structural unit (a2) represented by the following Formula (2) and a vinyl-group-containing structural unit (a1) represented by the following Formula (1):

##STR00001##

in the formulas, R.sup.1's independently represent an aromatic hydrocarbon group having 6 to 30 carbon atoms.

Provided is a polyfunctional vinyl aromatic copolymer having reactivity and solubility that can be used for manufacturing a copolymer rubber and a copolymer rubber material having processability, strength and homogeneity obtained therefrom. The polyfunctional vinyl aromatic copolymer includes: 0.5 mol % or more and 40 mol % or less of a structural unit (a) derived from a divinyl aromatic compound and 60 mol % or more and 99.5 mol % or less of a structural unit (b) derived from a monovinyl aromatic compound, in which at least some of the structural units (a) are a crosslinked structural unit (a2) represented by the following Formula (2) and a vinyl-group-containing structural unit (a1) represented by the following Formula (1):

##STR00001##

in the formulas, R.sup.1's independently represent an aromatic hydrocarbon group having 6 to 30 carbon atoms.

UV-absorbing polymers are provided that have at least one anhydride repeating unit that is covalently attached to at least one UV-absorbing moiety selected from the group consisting of functionalized dibenzoylmethanes, benzophenone sulfonamides, triphenyl triazines, and combinations thereof. Also provided are formulations comprising the UV-absorbing polymers.

UV-absorbing polymers are provided that have at least one anhydride repeating unit that is covalently attached to at least one UV-absorbing moiety selected from the group consisting of functionalized dibenzoylmethanes, benzophenone sulfonamides, triphenyl triazines, and combinations thereof. Also provided are formulations comprising the UV-absorbing polymers.

A graft copolymer can include, in its backbone, at least one segment having repeating units obtainable by ring-opening metathesis polymerization (ROMP) of an optionally substituted cycloalkene, and at least one segment comprising repeating units obtainable by atom transfer radical polymerization (ATRP) of a (meth)acrylate. The corresponding graft copolymer is highly suitable for use as an oil additive in internal combustion engines, in particular, in combustion engines which are operated for longer periods of time at substantially constant operating temperatures.

A graft copolymer can include, in its backbone, at least one segment having repeating units obtainable by ring-opening metathesis polymerization (ROMP) of an optionally substituted cycloalkene, and at least one segment comprising repeating units obtainable by atom transfer radical polymerization (ATRP) of a (meth)acrylate. The corresponding graft copolymer is highly suitable for use as an oil additive in internal combustion engines, in particular, in combustion engines which are operated for longer periods of time at substantially constant operating temperatures.

The present invention discloses a process for providing a cross-linked composition, the process comprising the steps of (a) providing an ethylene-?-olefin plastomer havinga density of from 850 kg/m.sup.3 to 900 kg/m.sup.3; andan melt flow rate (ISO 1133, 2.16 kg, 190? C.) of 0.3 to 50 g/10 min; (b) grafting the ethylene-?-olefin plastomer with silane crosslinker such that the content of silane crosslinker is in the range of 0.1 to 10.0 wt. % with respect to the grafted ethylene-?-olefin plastomer; (c) contacting said grafted ethylene-?-olefin plastomer with 2 to 8 wt. % of a tin-free silane crosslinking catalyst with respect to the resulting mixture of grafted ethylene-?-olefin plastomer and tin-freesilane crosslinking catalyst, wherein said tin-free catalyst comprises a Br?nsted acid at 23? C. and 50% relative humidity for at least 15 minutes thus forming a cross-linked composition, wherein gel content of said cross-linked composition after 15 min is at least 60%.

The present invention discloses a process for providing a cross-linked composition, the process comprising the steps of (a) providing an ethylene-?-olefin plastomer havinga density of from 850 kg/m.sup.3 to 900 kg/m.sup.3; andan melt flow rate (ISO 1133, 2.16 kg, 190? C.) of 0.3 to 50 g/10 min; (b) grafting the ethylene-?-olefin plastomer with silane crosslinker such that the content of silane crosslinker is in the range of 0.1 to 10.0 wt. % with respect to the grafted ethylene-?-olefin plastomer; (c) contacting said grafted ethylene-?-olefin plastomer with 2 to 8 wt. % of a tin-free silane crosslinking catalyst with respect to the resulting mixture of grafted ethylene-?-olefin plastomer and tin-freesilane crosslinking catalyst, wherein said tin-free catalyst comprises a Br?nsted acid at 23? C. and 50% relative humidity for at least 15 minutes thus forming a cross-linked composition, wherein gel content of said cross-linked composition after 15 min is at least 60%.

A graft copolymer can include, in its backbone, at least one segment having repeating units obtainable by ring-opening metathesis polymerization (ROMP) of an optionally substituted cycloalkene, and at least one segment comprising repeating units obtainable by atom transfer radical polymerization (ATRP) of a (meth)acrylate. The corresponding graft copolymer is highly suitable for use as an oil additive in internal combustion engines, in particular, in combustion engines which are operated for longer periods of time at substantially constant operating temperatures.

A modified polyolefin resin may be capable of obtaining an intended adhesion strength regardless of a kind of a base resin thereof even when graft modification is carried out by using an ?,?-unsaturated carboxylic acid derivative having a cyclic structure. Such a modified polyolefin resin may be a modified product of a polyolefin resin and satisfying (A) and (B): (A): a modifying component includes an ?,?-unsaturated carboxylic acid derivative having a cyclic structure; and (B): a ring-opening degree expressed by formula (1) is 40 or more:
ring-opening degree=modification degree K?ring-opening rate R(1),
wherein, in formula (1), the modification degree K is a grafting weight (% by weight) of the ?,?-unsaturated carboxylic acid derivative, and the ring-opening rate R is a ring-opening rate (%) of the cyclic structure in the ?,?-unsaturated carboxylic acid derivative.