丙烯酸酯乳液型压敏胶的聚合稳定性研究

以丙烯酸丁酯(BA)、丙烯酸-2-羟基丙基酯(HPA)、β-羧乙基丙烯酸酯(β-CEA)和苯乙烯(St)为共聚单体,过硫酸铵(APS)为引发剂,碳酸氢钠(NaHCO3)为缓冲剂,DNS-458(铵盐型阴离子乳化剂)/OP-10(普通非离子乳化剂)为复合乳化剂,采用半连续种子乳液聚合法合成了丙烯酸酯乳液型PSA(压敏胶)。研究了单体、乳化剂、引发剂及缓冲剂等对乳液聚合稳定性的影响。结果表明:共聚单体对乳液聚合稳定性的影响依次为β-CEABA≈HPASt,β-CEA单体对聚合稳定性影响最显著;当w(APS)=0.6%、w(NaHCO3)≥0.3%、复合乳化剂中m(DNS-458)∶m(OP-10)=1∶1且w(DNS-458+OP-10)=0.5%时,乳液的聚合稳定性相对较好。

Study on polymerization stability of acrylate emulsion PSA

With butyl acrylate(BA),acrylic-2-hydroxy-propyl ester(HPA),β-carboxyl ethyl acrylate(β-CEA) and styrene(St) as comonomer,ammonium persulfate(APS) as initiator,NaHCO3 as buffering agent and DNS-458(ammonium salt-type anionic emulsifier)/OP-10(general non-ionic emulsifier) as compound emulsifier,so an acrylate emulsion PSA(pressure sensitive adhesive) was synthesized by semi-continuous seed emulsion polymeriza-tion.The influences of monomer,emulsifier,initiator and buffering agent were investigated on stability of emulsion polymeri-zation.The results showed that the influences of comonomers on stability of emulsion polymerization were β-CEA>BA≈HPA>St,and the influence of β-CEA monomer on polymerization stability was most evident.The stability of emulsion polymerization was relatively optimal when the mass fractions of APS and NaHCO3 were 0.6% and not less than 0.3% respectively,the mass ratio of m(DNS-458)∶m(OP-10) was 1∶1 and mass fraction of DNS-458 and OP-10 was 0.5% in composite emulsifier.