水性油墨用纯丙乳液的合成及在BOPP薄膜上的附着牢度

Synthesis of polyacrylate emulsion for water-based ink and its adhesion behavior on BOPP film

以甲基丙烯酸甲酯(MMA)为硬单体,丙烯酸乙酯(EA)、丙烯酸丁酯(nBA)、丙烯酸异辛酯(2-EHA)为软单体,甲基丙烯酸(MAA)为功能单体,过硫酸铵(APS)为引发剂,碳酸氢钠(NaHCO3)为缓冲剂,十二烷基硫酸钠(SDS)、脂肪醇聚氧乙烯醚(AEO-9)为乳化剂,采用半连续种子乳液聚合方法合成软单体不同的水性聚丙烯酸酯乳液。利用衰减全反射-傅里叶变换红外光谱(ATR-FTIR)、核磁共振氢谱(1 H-NMR)、热重分析(TG)、动态热机械分析(DMA)和X射线衍射仪(XRD)表征水性聚丙烯酸酯乳液的结构和热性能。用表面张力仪和接触角仪测试乳液的表面张力以及在双向拉伸聚丙烯(BOPP)薄膜上的接触角,计算乳液与BOPP薄膜之间的附着功和界面张力。结果表明:合成的水性聚丙烯酸酯为无定形共聚物,具有良好的热稳定性,乳液与BOPP薄膜之间的附着牢度与附着功成正比,乳液在BOPP薄膜上的附着牢度为P(MMA-2-EHA-MAA)>P(MMA-nBA-MAA)>P(MMA-EA-MAA)。所以2-EHA做软单体合成的聚合物与聚丙烯的分子间作用力更大。

A series of waterborne polyacrylate emulsion with different soft segment were synthesized by semicontinuous emulsion polymerization technology using methyl methacrylate（MMA）as hard monomer,ethyl acrylate（EA）,n-butyl acrylate（nBA）and 2-ethylhexyl acrylate（2-EHA）as soft monomers,methylacrylic acid（MAA）as functional monomer,ammonium persulfate（APS）as initiator,sodium bicarbonate（NaHCO3）as buffer agent,sodium dodecyl sulfate（SDS）and AEO-9 as emulsifier.Attenuated total reflection-Fourier transform infrared spectroscopy（ATR-FTIR）,proton nuclear magnetic resonance spectroscopy（1 H-NMR）,thermogravimetric analysis（TG）,dynamic thermomechanical analysis（DMA）and X-ray diffractometer（XRD）measurements were utilized to characterize the bulk structures and thermal properties of polyacrylate emulsion.Tensiometer and contact angle meter measurements were utilized to test the surface tension of polyacrylate emulsion and contact angle on BOPP film,and calculated the work of adhesion and interfacial tension between emulsions and BOPP film.The results showed that the polyacrylate synthesized was an amorphous copolymer with good thermal stability.The adhesion of emulsion on BOPP film was proportional to the work of adhesion,the adhesion was in the order of P（MMA-2-EHA-MAA）〉P（MMA-nBAMAA）〉P（MMA-EA-MAA）.Therefore,the intermolecular force between polymer with 2-EHA as soft segment and polypropylene was greater.