TPGDA加料顺序对聚丙烯酸酯乳液性能的影响

Effect of TPGDA adding order on the properties of polyacrylate emulsion

以二缩三丙二醇二丙烯酸酯(TPGDA)为交联单体,采用半连续种子预乳化工艺,通过在聚合前期或后期集中引入交联剂的2种加料顺序,合成了系列TPGDA内交联改性聚丙烯酸酯乳液。采用激光粒度仪、动态热机械分析仪、拉力试验机、热重分析仪等研究了工艺顺序、TPGDA用量对乳液及乳胶膜性能的影响。结果表明:TPGDA的加料顺序对改性效果影响显著。前期引入利于形成小粒径、窄分布乳液,提高成膜物的杨氏模量与热稳定性。后期引入利于提高乳液干燥速率,增强成膜物抗热返粘性与邵氏硬度。TPGDA的质量分数以0.5%为宜,内交联剂引入工艺顺序应根据两种工艺的改性特点结合实际应用需求选择。

A series of TPGDA internal cross-linked modified polyacrylate emulsions were synthesized via pre-emulsification semi-continuous seed emulsion polymerization by using tri(propylene glycol)diacrylate(TPGDA)as crosslinking monomer and two adding orders of crosslinking agent in the early or late stage of polymerization.The effects of TPGDA dosage and adding order on the properties of emulsion and latex film were studied by laser particle size analyzer,dynamic thermomechanical analyzer,tensile testing machine and thermogravimetric analyzer.The results showed that the adding order of TPGDA had a significant effect on the modification effect.The early introduction was beneficial to the synthesis of emulsion with small particle size and narrow size distribution,and improve the young’s modulus and thermal stability of the latex film.The later introduction was beneficial to improve the drying rate of emulsion,and enhance the resistance to thermal back adhesion and shore hardness of the latex film.The mass fraction of TPGDA should be 0.5%,and the adding order of crosslinking agent should be determined according to the modification characteristics of two processes and the practical application requirements.