The present invention is a powdered dispersant for hydraulic compositions containing a copolymer obtained by polymerizing raw material monomers containing a predetermined monomer 1 containing AO group with a number of added moles n falling within a predetermined range and a predetermined monomer 2 having a predetermined group such as a carboxylic acid group or the like, wherein a ratio of monomer 2 in the raw material monomers is 22 mass % or more, and a product of a value of n of monomer 1 and a value of mass % of the ratio is 420 or more and 2600 or less.

A (meth)acrylic copolymer of the present invention includes a constituent unit (B) derived from a polysiloxane block-containing polymerizable monomer (b) represented by Formula (b1). In Formula (b1), R.sup.30 represents a hydrogen atom or a methyl group, a represents an integer of 2 to 5, b represents a number of 0 to 50, c represents an integer of 0 to 18, d represents a number of 1 to 1000, e represents a number of 1 to 80, R.sup.31 to R.sup.39 each represents an alkyl group, an alkoxy group, a phenyl group, a substituted phenyl group, a phenoxy group, or a substituted phenoxy group.

A (meth)acrylic copolymer of the present invention includes a constituent unit (B) derived from a polysiloxane block-containing polymerizable monomer (b) represented by Formula (b1). In Formula (b1), R.sup.30 represents a hydrogen atom or a methyl group, a represents an integer of 2 to 5, b represents a number of 0 to 50, c represents an integer of 0 to 18, d represents a number of 1 to 1000, e represents a number of 1 to 80, R.sup.31 to R.sup.39 each represents an alkyl group, an alkoxy group, a phenyl group, a substituted phenyl group, a phenoxy group, or a substituted phenoxy group.

An object of the present disclosure is to provide a rubber composition from which a crosslinked rubber molded product having good softness and excellent resilience performance can be obtained. The present disclosure provides a rubber composition containing (a) a base rubber, (b) an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, (c) a crosslinking initiator, and (d) a benzothiazole derivative, and further comprising (e) a metal compound when (b) the co-crosslinking agent consists of the α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, wherein (d) the benzothiazole derivative is a compound represented by the formula (1) and/or a compound represented by the formula (2).

##STR00001## [R.sup.1 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 4 to 14 carbon atoms, or a metal atom, R.sup.2 to R.sup.5 are identical to or different from each other, and represent an electron-withdrawing group or a hydrogen atom, and at least one of R.sup.3 to R.sup.5 is an electron-withdrawing group.]

An object of the present disclosure is to provide a rubber composition from which a crosslinked rubber molded product having good softness and excellent resilience performance can be obtained. The present disclosure provides a rubber composition containing (a) a base rubber, (b) an α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms and/or a metal salt thereof as a co-crosslinking agent, (c) a crosslinking initiator, and (d) a benzothiazole derivative, and further comprising (e) a metal compound when (b) the co-crosslinking agent consists of the α,β-unsaturated carboxylic acid having 3 to 8 carbon atoms, wherein (d) the benzothiazole derivative is a compound represented by the formula (1) and/or a compound represented by the formula (2).

##STR00001## [R.sup.1 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 4 to 14 carbon atoms, or a metal atom, R.sup.2 to R.sup.5 are identical to or different from each other, and represent an electron-withdrawing group or a hydrogen atom, and at least one of R.sup.3 to R.sup.5 is an electron-withdrawing group.]

A curable composition for an electronic device, includes a curable material; and an oxide-containing complex; wherein the oxide-containing complex includes i) an oxide core and ii) an organic group chemically bound to an atom on a surface of the oxide core, the organic group includes a) a curable group reactable with the curable material and b) a linking group linking the atom on a surface of the oxide core to the curable group, and the oxide core includes an aluminum oxide, a silicon oxide, or a combination thereof.

A curable composition for an electronic device, includes a curable material; and an oxide-containing complex; wherein the oxide-containing complex includes i) an oxide core and ii) an organic group chemically bound to an atom on a surface of the oxide core, the organic group includes a) a curable group reactable with the curable material and b) a linking group linking the atom on a surface of the oxide core to the curable group, and the oxide core includes an aluminum oxide, a silicon oxide, or a combination thereof.

A golf ball with improved durability is disclosed herein. The golf ball has a core comprising a polybutadiene material and methyl methacrylate, butadiene, styrene (MBS) with a weight percentage of MBS ranging from 0.5 to 5 weight percent of the core.

A golf ball with improved durability is disclosed herein. The golf ball has a core comprising a polybutadiene material and methyl methacrylate, butadiene, styrene (MBS) with a weight percentage of MBS ranging from 0.5 to 5 weight percent of the core.

Methods for forming latexes are provided. In an embodiment, such a method comprises adding a monomer emulsion comprising water, a monomer, an acidic monomer, a hydrophilic monomer, a difunctional monomer, a first reactive surfactant, and a chain transfer agent, to a reactive surfactant solution comprising water, a second reactive surfactant, and an initiator, at a feed rate over a period of time so that monomers of the monomer emulsion undergo polymerization reactions to form resin particles in a latex. The reactive surfactant solution does not comprise monomers other than the second reactive surfactant, the reactive surfactant solution does not comprise a resin seed, and the monomer emulsion does not comprise the resin seed. The latex is characterized by a viscosity in a range of from about 10 cP to about 100 cP as measured at a solid content of about 30% and at room temperature. The latexes are also provided.