关键词: 纳米Fe₃O₄, Pickering乳液, ASA, 稳定性, 水解, 施胶性能

Abstract: Fe₃O₄ nanoparticles were used as stabilizer and emulsifier to prepare Pickering-type ASA (alkenyl succinic anhydride) emulsions, and the effects of particles concentration, volume ratio of oil/water and pH value on the type, stability, morphology and sizing performance of the emulsions were investigated. Fe₃O₄ nanoparticles were able to emulsify ASA to prepare homogeneous emulsions. When emulsions were placed without stirring at room temperature, the separated oil phase fraction increased with increasing particles concentration and decreased with increasing volume ratio of oil/water. Emulsions could keep homogeneous phase for 6 h as volume ratio of oil/water was 2 and particles concentration was 0.1%(mass). For stable emulsions, part of particles was absorbed at liquid-liquid interface and part of particles entered the dispersed phase, the stability of emulsions reduced with increasing particles concentration. Before the emulsions creamed, hydrolysis resistance was investigated and ASA was partially hydrolyzed. Sheet surface contact angle gradually increased by adding emulsions which were placed for 1 h, meanwhile surface roughness were decreased. When addition of ASA was 1.0%(mass relative to the absolute dry pulp), sheet surface contact angle reached 93.5? and surface roughness was 15.924 mm.

Key words: Fe₃O₄ nanoparticles, Pickering emulsions, ASA, stability, hydrolysis, sizing performance