Showing papers in "Leather and Chemicals in 2001"

Methods of De-chroming from Chrome Shavings

Abstract: In this paper, such de-chroming methods as acid, chelation and the combination of peroxide with chelation are studied to remove chrome from the shavings. The effects of the reagent amount and the agitation time on the chrome removal rate are included. The conclusion is that the combination method of peroxide with chelation is the best one. The chrome removal rate may be up to 94% in the proper condition.

Synthesis and Study of Amphoteric Vinyl Polymer Retanning Agent APT

Abstract: A new amphoteric vinyl polymer retanning agent has been synthesized by copolymerization of dimethyldiallyammonium chloride (DMDAAC) and vinyl monomer in adequate proportion in queous solution with ammonium persulfate (APS) as initiator When the mass concentration of monomers was 30%, the mass of initiator to monomer was 20% and the reaction temperature was 55?℃ for 15?h, the viscosity of the copolymer reached to 8?000?mP·s The application test shows that it has excellent selective filling properties and cannot bring about the question of pastel shade The applied leather had good quality characteristics such as feel, softness, and fullness Meanwhile, the structure and property was confirmed by chemical analysis and IR

Development of Aqueous Polyurethane Finishing Agent

Abstract: The classification, preparation and development of waterborne polyurethane for leather finishing were viewed in this paper. And the relationship of structure, properties and modification studies of waterborne polyurethane were also discussed in details. The possible developing trend of leather finishes is pointed out.

Alcoholysis Reaction in Fatliquor Synthesis

Abstract: The preparations of fatliquor intermediate by the anionic layer and pillar materials as the catalyst through the alcoholysis reaction, the fatty acid methyl ester and (mono and di)glyceride by vegetable oil as the raw materials through the ester exchange reaction, or the methyl acrylic acid higher alcohol ester by methyl acrylate through the alcoholysis reaction were related in this paper. The combined Fatliquor LWF, modified reap oil-based fatliquor, phosphated fatliquor and acrylic fatliquoring retanning agent could be obtained through their further synthesis.

Synthesis of Amphoteric Acrylic Polymer Syntan by Reduction Polymerization

Abstract: Amphoteric acrylic polymer syntan has been synthesized by copolymerization of acrylic monomers. The optimums of reaction conditions are obtained by orthoganal layout. The various tests are designed to determine the effects of this resin on leather. Results showed that the leather made by this polymer has satisfactory softness, fullness and hue.

Preparing Collagen from Chrome Shavings

Abstract: The processes for preparing collagen and collagen hydrolyzate from chrome shavings have been summarized in the present paper. These processes include the treatments with acids, alkalis, oxidants, enzymes, alkalis-enzymes as well as the alternate treatment with acids and alkalis. The processes with either alkalis or alkalis-enzymes have been put into operation in some factories on the production scale.