A method of modifying the surface characteristics of a substrate having a surface with an amide-functional polymer thereon. The method involves contacting the amide-functional polymer with a source of hydroxide ions and a source of hypohalite ions at a temperature of at least about 20° C. for a time effective to convert at least a portion of the amide-functional groups to amine-functional groups to form a substrate surface comprising an amine-functional polymer, wherein the hydroxide ions are present in a molar excess relative to the hypohalite ions and at a concentration of no more than about 0.1 M, based on the total volume of the reaction mixture. A biomolecule is attached to the resultant amine-functional polymer.

Method for attachment of biomolecules to surfaces through amine-functional groups

There is provided with an admixture for hydraulic cement comprising as an effective component a water-soluble amphoteric polymer obtained by Hofmann degradation reaction of an α,β-unsaturated carbonamide polymer or a copolymer of α,β-unsaturated carbonamide and an anionic monomer having a weight average molecular weight of 1,000 - 1,000,000 A substituent such as a primary amino group produced as a result of the Hofmann degradation reaction provides excellent cement dispersing capabilities

Admixture for hydraulic cement

PROBLEM TO BE SOLVED: To provide a production method of a polyamidine-based water-soluble polymer by which gelation in a step of lowering pH of a reaction product by an acid after a Hofmann reaction is prevented and as a result, stability of the generated polyamidine-based water-soluble polymer is enhanced. SOLUTION: In the production method by which the polyamidine-based water-soluble polymer is generated by lowering pH of the reaction product by an acid after a Hofmann reaction of a copolymer of a (meth)acrylamide monomer and a (meth)acrylonitrile, the polyamidine-based water-soluble polymer can be stably produced by coexistence of a reducing agent upon addition of the acid. COPYRIGHT: (C)2010,JPO&INPIT

Production method of polyamidine-based water-soluble polymer

PROBLEM TO BE SOLVED: To develop a method for producing a low-cost sludge dehydrating agent consisting of a polyamidine-based water-soluble polymer by solving such the problem that the polyamidine-based water-soluble polymer has excellent sludge dehydration performance but the production cost thereof can not be prevented from becoming high since N-vinyl formamide is used as a raw material and to provide a method for applying the sludge dehydrating agent to sludge dehydration treatment. SOLUTION: The sludge dehydrating agent consisting of the water-soluble polymer having an amidine structural unit is produced by subjecting the copolymer of (meth)acrylamide and (meth)acrylonitrile to the Hoffman's reaction, neutralizing the resulting copolymer with an acid and heat-treating the neutralized copolymer. The produced sludge dehydrating agent is added to biotreated sludge, the obtained mixture is agitated and the agitated mixture is dehydrated by using a dehydrator. COPYRIGHT: (C)2009,JPO&INPIT

Sludge dehydrating agent and method for dehydrating sludge

Series resin of polyvinyl amine and preparing process and application thereof

PURPOSE:To produce the titled polymer useful as a polymer flocculant, etc. in a remarkably improved yield, by reacting an acylamide polymer with a hypohalous acid salt in an aqueous solution in the presence of an alkali, treating with a reducing agent, aging under specific condition, and controlling the pH of the liquid. CONSTITUTION:An acrylamide polymer is made to react with a hypohalous acid salt in an aqueous solution in the presence of an alkali, and mixed with a reducing agent (e.g. sodium sulfite, etc.). The obtained mixture is aged at 30- 80 deg.C for >=30min and adjusted to <=5pH. The produced polymer can be precipitated as a concentrated hydrous polymer by this process, and the objective polymer decomposed partly by Hofmann degradation can be separated from the product. When the concentration of the aqueous solution of the polymer is too high, the viscosity increases to make stirring difficult, and accordingly, the concentration is preferably 1-15wt%.

Production of acrylamide polymer decomposed partly by hofmann degradation

PURPOSE:To produce the titled polymer by easy concentration by ultrafiltration, by controlling the pH value of a reaction mixture containing an acrylamide polymer subjected to Hofmann degradation to a specified value and effecting the ultrafiltration of the reaction mixture. CONSTITUTION:A reaction mixture containing an acrylamide polymer in which usually at least 20mol% of the amide groups are subjected to Hofmann degradation is obtained by reacting an acrylamide polymer in an aqueous solution with a hypohalite (e.g., sodium hypochlorite) in the presence of an alkali. Next, the pH value of this solution is controlled to 6-11, and the solution is concentrated by an ultrafilter. This pH control makes it possible to carry out the ultrafiltration easily and to effect the concentration of good polymer consistently.

Satou Shinichi

Papers

Production of acrylamide polymer decomposed partly by hofmann degradation

Production of acrylamide polymer subjected partially to hofmann degradation