| Abstract:A series of core-shell type cationic soap-free SAE latexes were prepared by using styrene(St), butyl acrylate(BA) and methyl methacrylate(MMA) as main materials and introducing functional monomer, by adding in drops continuously and using starch(CS-8), with high molecular weight and low viscosity as the emulsifier and the dispersant. The influence of functional monomer (cationic monomers and water-resistant functional monomers) on properties of styrene acrylate(SAE) and its surface sizing effect were studied, and the sizing effects between SAE and the commercial styrene-acrylate sizing agent 8906 and the commercial AKD were compared.In this study, DM (dimethylaminoethyl methacrylate), DAC (acryloyloxyethyltrimethyl ammonium chloride) and DMC (methacryloyloxyethyltrimethyl ammonium chloride) were selected as cationic monomers and rosin as water-resistant monomer. The effects of the type and dosage of cationic monomer and the dosage of rosin on the properties of SAE emulsion and its surface sizing features were investigated. The results showed that when DM is used with the dosage of 2%, the characteristics of the emulsion are much better. And the water-resistant performance and the tensile strength of the ink jet printing paper sized with SAE increases significantly compared to that of unsized paper. It also showed that when the amount of rosin is about 2%, emulsions with excellent performance were obtained by dissolving rosin into the mixed monomers and adding in drops continuously. And the water-resistant performance of the paper sized with the emulsion improves significantly. Compared to commercial surface sizing agent AKD and styrene-acrylate sizing agent 8906, SAE modified with DM and rosin is superior to AKD obviously in water resistance and physical strength of the paper, even a little better than 8906. |
