An acrylic rubber containing: an alkyl acrylate unit; a crosslinking monomer unit; a unit of a bifunctional monomer represented by the following formula (A-1):

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wherein n represents 1 to 9, R.sup.1 represents a hydrogen atom or a methyl group, and R.sup.2 represents an alkanediyl group having 2 to 4 carbon atoms; and an ethylene unit, wherein the acrylic rubber has a toluene insoluble content of 4 to 40% by mass.

A method for predicting physical properties of a polyethylene resin is provided, which can reliably predict a proper charging ratio of a crosslinking agent in the production process of a low density crosslinked polyethylene resin, and the physical properties of the polyethylene resin achieved therefrom. A method for producing a polyethylene resin by applying the same method is also provided.

A method for predicting physical properties of a polyethylene resin is provided, which can reliably predict a proper charging ratio of a crosslinking agent in the production process of a low density crosslinked polyethylene resin, and the physical properties of the polyethylene resin achieved therefrom. A method for producing a polyethylene resin by applying the same method is also provided.

Provided is a copolymer consisting essentially of ethylene units, tetrafluoroethylene units, and hexafluoropropylene units, wherein a molar ratio (Et units/TFE units) of the ethylene (Et) units to the tetrafluoroethylene (TFE) units is 52.0/48.0 to 56.0/44.0, and a content of the hexafluoropropylene units is 19.0 to 21.0 mol % based on the total monomer units constituting the copolymer.

Provided is a copolymer consisting essentially of ethylene units, tetrafluoroethylene units, and hexafluoropropylene units, wherein a molar ratio (Et units/TFE units) of the ethylene (Et) units to the tetrafluoroethylene (TFE) units is 52.0/48.0 to 56.0/44.0, and a content of the hexafluoropropylene units is 19.0 to 21.0 mol % based on the total monomer units constituting the copolymer.

In one aspect, the disclosure relates to the production of alternating polymers of maleic anhydride or an N-substituted maleimide with a stilbene.

A polymer includes: structural units A derived from at least one selected from the group consisting of ethylene and propylene; structural units B represented by a formula (1) below; and structural units C represented by a formula (2) below. In the formula (1), L.sup.16 represents —(CH.sub.2).sub.n—(R.sup.f2O).sub.p—R.sup.f1, R.sup.f1 represents a C.sub.1-15 alkyl group having one or more hydrogen atoms thereof substituted with one or more fluorine atoms, R.sup.f2 represents a C.sub.1-15 alkylene group having one or more hydrogen atoms thereof substituted with one or more fluorine atoms, p represents an integer of 0 to 15, and n represents an integer of 0 to 10. In the formula (2), L.sup.26 represents —(CH.sub.2).sub.n— (R.sup.r2O).sub.q—R.sup.r1, R.sup.r1 represents a hydrogen atom or a C.sub.1-15 alkyl group, R.sup.r2 represents a C.sub.1-15 alkylene group, q represents an integer of 0 to 1000000, and n represents an integer of 0 to 10.

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A polymer includes: structural units A derived from at least one selected from the group consisting of ethylene and propylene; structural units B represented by a formula (1) below; and structural units C represented by a formula (2) below. In the formula (1), L.sup.16 represents —(CH.sub.2).sub.n—(R.sup.f2O).sub.p—R.sup.f1, R.sup.f1 represents a C.sub.1-15 alkyl group having one or more hydrogen atoms thereof substituted with one or more fluorine atoms, R.sup.f2 represents a C.sub.1-15 alkylene group having one or more hydrogen atoms thereof substituted with one or more fluorine atoms, p represents an integer of 0 to 15, and n represents an integer of 0 to 10. In the formula (2), L.sup.26 represents —(CH.sub.2).sub.n— (R.sup.r2O).sub.q—R.sup.r1, R.sup.r1 represents a hydrogen atom or a C.sub.1-15 alkyl group, R.sup.r2 represents a C.sub.1-15 alkylene group, q represents an integer of 0 to 1000000, and n represents an integer of 0 to 10.

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The polymerizable composition for an optical material of the present invention includes a compound (A) represented by General Formula (a) and including two or more allyloxycarbonyl groups, at least one kind of radical polymerization initiator (B) selected from the group consisting of a peroxyketal-based radical polymerization initiator, a peroxymonocarbonate-based radical polymerization initiator, and a peroxyester-based radical polymerization initiator, and a modifier (C) selected from a polyether modified siloxane compound represented by General Formula (c1) or a polyol compound represented by General Formula (c2). ##STR00001##

The polymerizable composition for an optical material of the present invention includes a compound (A) represented by General Formula (a) and including two or more allyloxycarbonyl groups, at least one kind of radical polymerization initiator (B) selected from the group consisting of a peroxyketal-based radical polymerization initiator, a peroxymonocarbonate-based radical polymerization initiator, and a peroxyester-based radical polymerization initiator, and a modifier (C) selected from a polyether modified siloxane compound represented by General Formula (c1) or a polyol compound represented by General Formula (c2). ##STR00001##