US 7,732,527 B2 · Water-soluble polymers reduced in molecular weight, process for production thereof and usage thereof

Abstract

The invention relates to water-soluble polymers reduced in molecular weight, a process for production of the same, and usage thereof. It makes it possible to obtain water-soluble polymers reduced in molecular weight by a simple procedure and in an economical and simple manner by subjecting either an aqueous solution admixed with an aqueous solution of an oxidizing agent and containing an amount within the range of 10-60% by mass of a water-soluble polymer and having a viscosity of not lower than 3000 mPa·s or a granular composition admixed or impregnated with an aqueous solution of an oxidizing agent and containing an amount within the range of 10-60% by mass of a water-soluble polymer to oxidation reaction, not by the method of polymerization at elevated temperatures, which is an energy-consuming method, or by the method of polymerization using large amounts of a chain transfer agent and/or an initiator, which is one of the raw materials, and these water-soluble polymer reduced in molecular weight can be used fixing agents for improving the water resistance and/or light fastness of printed matters and, further, the solution viscosity of this water-soluble polymer reduced in molecular weight can be adjusted, hence the handleability thereof, among others, can be adjusted, by incorporating a water-soluble salt and/or a polymer additive in these water-soluble polymers reduced in molecular weight to give compositions comprising the water-soluble polymer reduced in molecular weight.

Claims6

Dependent claims

A water-soluble polymer reduced in molecular weight as obtained by subjecting either an aqueous solution admixed with an aqueous solution of an oxidizing agent and containing an amount within the range of 10-60% by mass of a water-soluble polymer and having a viscosity of not lower than 3000 mPa·s determined using a rotation viscometer or a granular composition admixed or impregnated with an aqueous solution of an oxidizing agent and containing an amount within the range of 10-60% by mass of a water-soluble polymer to oxidation reaction to thereby reduce the degree of polymerization of the water-soluble polymer, characterized in that the oxidation reaction is carried out without stirring and the water-soluble polymer is a cationic water-soluble polymer comprising at least one structural unit selected from among the cationic structural units represented by the general formulas (1) to (4) given below:

wherein R1 is a hydrogen atom or a methyl group, R2 and R3 each is an alkyl or alkoxyl group containing 1-3 carbon atoms, R4 is a hydrogen atom, an alkyl or alkoxyl group containing 1-3 carbon atoms or a benzyl group, and R1-R4 may be the same or different, A represents an oxygen atom or NH, B represents an alkylene or alkoxylene group containing 2-4 carbon atoms, and X1 represents an anion;
wherein R5 and R6 each represents a hydrogen atom or a methyl group, R7 and R8 each represents an alkyl or alkoxyl group containing 1-3 carbon atoms or a benzyl group, and X2 represents an anion;
wherein R9 and R10 each represents a hydrogen atom or a methyl group and X3 represents an anion;
and
wherein R11 represents a hydrogen atom or a methyl group and X4 represents an anion.

2 more elements

A water-soluble polymer reduced in molecular weight as obtained by subjecting either an aqueous solution admixed with an aqueous solution of an oxidizing agent and containing an amount within the range of 10-60% by mass of a water-soluble polymer and having a viscosity of not lower than 3000 mPa·s determined by using a rotation viscometer or a granular composition admixed or impregnated with an aqueous solution of an oxidizing agent and containing an amount within the range of 10-60% by mass of a water-soluble polymer to oxidation reaction to thereby reduce the degree of polymerization of the water-soluble polymer, characterized in that the oxidation reaction is carried out without stirring and the water-soluble polymer is a nonionic water-soluble polymer comprising at least one structural unit selected from among nonionic structural units represented by the general formula (6) given below:

wherein R14 represents a hydrogen atom or a methyl group, R15 represents a hydrogen atom or a lower alkyl group, and Q represents NHCOR16 in which R16 is a hydrogen atom or a lower alkyl group, or COA in which A is NH or O and Y3 represents a hydrogen atom.

Dependencies are inferred from the claim text.

Water-soluble polymers reduced in molecular weight, process for production thereof and usage thereof

Life of this patent

Water-soluble polymers reduced in molecular weight, process for production thereof and usage thereof

Life of this patent

Abstract

Claims6