An acidic water-based process was developed for the synthesis of anionic lignin copolymers with adjustable MW, thermal stability and solubility in water. The anionic lignin copolymer described herein comprises: a molecular weight of 5,000 to 7.410.sup.5 g/mol; and a charge density of 1 to 7.2 meq/g. The anionic lignin copolymers described herein which have a molecular weight range of 000-50,000 g/mol can be used as dispersants of negatively charged molecules or particles in numerous process or wastewater streams (e.g. concrete admixtures, gypsum slurries, textile dye) while such copolymers in a molecular weight range of 90,000-740,000 g/mole can be used as flocculants of positively charged molecules or particles in numerous process and wastewater streams including industrial and municipal systems and sludge dewatering in the textile dye, pulp & paper, mining and oil industries.

An acidic water-based process was developed for the synthesis of anionic lignin copolymers with adjustable MW, thermal stability and solubility in water. The anionic lignin copolymer described herein comprises: a molecular weight of 5,000 to 7.410.sup.5 g/mol; and a charge density of 1 to 7.2 meq/g. The anionic lignin copolymers described herein which have a molecular weight range of 000-50,000 g/mol can be used as dispersants of negatively charged molecules or particles in numerous process or wastewater streams (e.g. concrete admixtures, gypsum slurries, textile dye) while such copolymers in a molecular weight range of 90,000-740,000 g/mole can be used as flocculants of positively charged molecules or particles in numerous process and wastewater streams including industrial and municipal systems and sludge dewatering in the textile dye, pulp & paper, mining and oil industries.

An acidic water-based process was developed for the synthesis of anionic lignin copolymers with adjustable MW, thermal stability and solubility in water. The anionic lignin copolymer described herein comprises: a molecular weight of 5,000 to 7.410.sup.5 g/mol; and a charge density of 1 to 7.2 meq/g. The anionic lignin copolymers described herein which have a molecular weight range of 000-50,000 g/mol can be used as dispersants of negatively charged molecules or particles in numerous process or wastewater streams (e.g. concrete admixtures, gypsum slurries, textile dye) while such copolymers in a molecular weight range of 90,000-740,000 g/mole can be used as flocculants of positively charged molecules or particles in numerous process and wastewater streams including industrial and municipal systems and sludge dewatering in the textile dye, pulp & paper, mining and oil industries.

Provided are an asphalt-like material and a method and use thereof as a plugging agent, and a water-based drilling fluid. The asphalt-like material has a structure shown in formula I, wherein, in the formula I, R.sup.1 is selected from the group consisting of H, COOH, and CH.sub.2COOH; R.sup.2 is selected from the group consisting of NHCH.sub.2CH.sub.2OH, NHCH.sub.2CH.sub.2NH.sub.2, N(CH.sub.2CH.sub.2OH).sub.2, and NHCH.sub.2CH.sub.2CH.sub.2OH; R.sup.3 is selected from the group consisting of OH, NHCH.sub.2CH.sub.2OH, NHCH.sub.2CH.sub.2NH.sub.2, N(CH.sub.2CH.sub.2OH).sub.2, and NHCH.sub.2CH.sub.2CH.sub.2OH; R.sup.4 is selected from the group consisting of NHCH.sub.2CH.sub.2OH, NHCH.sub.2CH.sub.2NH.sub.2, N(CH.sub.2CH.sub.2OH).sub.2, and NHCH.sub.2CH.sub.2CH.sub.2OH; and n is 370 to 400.

##STR00001##

Provided are an asphalt-like material and a method and use thereof as a plugging agent, and a water-based drilling fluid. The asphalt-like material has a structure shown in formula I, wherein, in the formula I, R.sup.1 is selected from the group consisting of H, COOH, and CH.sub.2COOH; R.sup.2 is selected from the group consisting of NHCH.sub.2CH.sub.2OH, NHCH.sub.2CH.sub.2NH.sub.2, N(CH.sub.2CH.sub.2OH).sub.2, and NHCH.sub.2CH.sub.2CH.sub.2OH; R.sup.3 is selected from the group consisting of OH, NHCH.sub.2CH.sub.2OH, NHCH.sub.2CH.sub.2NH.sub.2, N(CH.sub.2CH.sub.2OH).sub.2, and NHCH.sub.2CH.sub.2CH.sub.2OH; R.sup.4 is selected from the group consisting of NHCH.sub.2CH.sub.2OH, NHCH.sub.2CH.sub.2NH.sub.2, N(CH.sub.2CH.sub.2OH).sub.2, and NHCH.sub.2CH.sub.2CH.sub.2OH; and n is 370 to 400.

##STR00001##

The thermoplastic resin composition contains a graft copolymer produced using a rubbery polymer having a high gel content. A molded article is produced by molding the thermoplastic resin composition. A rubbery polymer (A) that is a product of polymerization of a raw material mixture contains an alkyl (meth)acrylate, a crosslinking agent (1) represented by Formula (1) below, and a hydrophobic substance. The amount of the hydrophobic substance is 0.1 to 10 parts by mass relative to 100 parts by mass of the total amount of the alkyl (meth)acrylate and the crosslinking agent (1). The rubbery polymer (A) has a gel content of 80% to 100%.

CH.sub.2CR.sup.1CO(X)COCR.sup.1CH.sub.2(1)

where X represents a diol residue selected from a polyalkylene glycol residue, a polyester diol residue, and a polycarbonate diol residue, and R.sup.1 represents H or CH.sub.3.

The thermoplastic resin composition contains a graft copolymer produced using a rubbery polymer having a high gel content. A molded article is produced by molding the thermoplastic resin composition. A rubbery polymer (A) that is a product of polymerization of a raw material mixture contains an alkyl (meth)acrylate, a crosslinking agent (1) represented by Formula (1) below, and a hydrophobic substance. The amount of the hydrophobic substance is 0.1 to 10 parts by mass relative to 100 parts by mass of the total amount of the alkyl (meth)acrylate and the crosslinking agent (1). The rubbery polymer (A) has a gel content of 80% to 100%.

CH.sub.2CR.sup.1CO(X)COCR.sup.1CH.sub.2(1)

where X represents a diol residue selected from a polyalkylene glycol residue, a polyester diol residue, and a polycarbonate diol residue, and R.sup.1 represents H or CH.sub.3.

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.

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.