| Using Fenton reagent as initiator, cassava starch as main chain, the styrene (St), butyl acrylate(BA), rosin, dimethyl amino ethyl methacrylate(DM) and N-hydroxymethyl acrylamide (NMA) as main monomers，the soap-free emulsion sizing agent based on cassava starch grafted by styrene-acrylate comonomer was prepared by free-soap emulsion polymerization, and the structure and properties of the copolymer were characterized by FT-IR, TGA, particle size analyzer, static contact angle and SEM. The results showed that the excellent performance of styrene-acrylate copolymer emulsion was achieved when the dosage of starch was 10%, the mass ratio of total monomers and starch was 2∶1, the mass ratio of St and BA was 3∶1, the dosage of H2O2, rosin, DM and NMA were 5.0%, 0.8%, 1.2% and 0.2%, respectively. When the dosage of soap-free emulsion was 0.4% on the surface sizing agent, sizing degree was 46 s and ring crush index was 5.47 N·m/g. |
