炔基改性光固化丙烯酸酯压敏胶

Acetylene Functionalized Photo-curable Acrylic Pressure Sensitive Adhesives

光固化是实现丙烯酸酯压敏胶无溶剂化和高性能化的可行手段。利用炔基功能化丙烯酸酯的光聚合特性,本工作以丙烯酸-1-环己基丙炔酯(ECA)为炔基功能单体,采用先本体光聚合制备流动性好、无凝胶的无溶剂压敏胶预聚物,再加入适量硬单体进一步光固化的两步方式,制备了炔基功能化丙烯酸酯压敏胶。随ECA加入量的增加(0~3 mol%),预聚物中丙烯酸酯聚合物的分子量从55.59×10^(4) Da降低到14.12×10^(4) Da,分子量分布有所加宽,炔基得以保留。对比研究表明,炔基提高了光固化压敏胶的动态和静态剪切性能,但对剥离力和初黏性没有或有极小影响。炔基参与光固化,增加了压敏胶的内聚强度,将是压敏胶改性的新手段。

Photocuring is an effective way to achieve solvent-free and high-performance acrylate pressure-sensitive adhesives. With ethynyl cyclohexyl acrylate(ECA) as the alkyne functional monomer and using its photopolymerization characteristics, solvent-free and gel-free syrup and their final acrylate pressure-sensitive adhesive are prepared in two steps by photocuring the syrup prepared by bulk photopolymerization. With the increase of ECA addition(0~3 mol%), the molecular weights of the polymers containing the retained acetylene groups in the precursors decreased from 55.59×10^(4) Da to 14.12×10^(4) Da and molecular weight distribution slightly increased. Comparative studies have shown that acetylene groups improve the dynamic and static shear properties of the photocured pressure-sensitive adhesives, but have no or minimal effect on the peeling and tack forces. The acetylene group participates in photocuring, which increases the cohesion strength of the pressure-sensitive adhesive and will be a new means for pressure-sensitive adhesives modification.