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A novel amphoteric polycarboxylate superplasticizer (APCs) was prepared by solution copolymerization from acrylic acid (AA), allyl polyethylene glycol (APEG), diallyldimethyl ammonium chloride (DMDAAC). Effects of DMDAAC dosage and monomers ratio on performance of APCs were investigated by tested of zeta potential of cement particles and adsorption on cement. Results indicated that introducing of cationic monomer can increase the saturation adsorption amount and dispersibility of APCS. When the molar ratio of AA and APEG and DMDAAC is 5:1:0.5, the dispersibility of APcs has the best adsorptivity and disersibility. The synergistic effects of Zeta potential and steric repulsion of the cement particles surface is the main mechanism for dispersion.

Effect of polycarboxylate superplasticizer (PCs) with different bond between side chain and truck chain on hydration of cement in early period was studied. The performance of PCs in concrete was investigated by setting time, TGA and SEM. PC-based superplasticizer with ester bonding between side chain and truck chain. Although they had the proximate structure parameters in density of side chain and absorption group (carboxyl groups), the setting time of cement paste was significantly different when different PCs were employed in the preparation of cement. Decomposing of this bond in alkali environment may lead to a shorter setting time. On the other hand, same difference in hydration production was observed in early period hydration of cement paste when two different PCs was incorporated, which indicated that the different bond structure in PCs affected the hydration of cement in a different manner. The result of SEM indicated that the morphological phase of hydrated product was different when PC was applied, this may be related with the different result in the TG and TGA

A phenolic syntan GA-SHBS had been synthesized by radical copolymerization of gallic acid (GA) and sodium 4-hydroxybenzenesulfonate (SHBS) using horseradish peroxides (HRP)/H2O2 as catalyst. The effects of monomer ratio, reaction temperature and HRP dosage on syntan were discussed. The optimum performance of GA-SHBS was got when the molar ratio of GA: SHBS is 1:1 in the presence of 5 mg HRP at 35°C in pH 7.0. The chemical structure of copolymer was characterized by means of FTIR and NMR. The mechanism of polymerization between GA and SHBS and binding mechanism between syntans and leather fibers were proposed. The copolymer was used in making leather as tanning agent and retanning agent respectively, applied results showed that the Ts of tanned leather can reach to 75.6°C, re-tanned leather has the merits of good uniformity, fullness, softness, fine grain and non-plastic feel etc. Syntan also has good permeability, excellent tanning performance and dyeing effect.