Kim Eun Seon, Lee Jae Heung, Suh Dong Hack, Choi Woo Jin
Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon, 34114 Korea.
Department of Chemical Engineering, Hanyang University, Seoul, 04763 Korea.
Macromol Res. 2021;29(2):129-139. doi: 10.1007/s13233-021-9018-3. Epub 2021 Mar 2.
Acrylic pressure sensitive adhesives (PSAs) were prepared by UV polymerization under varying curing conditions of both fast and slow curing, employing high- and low-intensity UV radiation, respectively. The influences of curing conditions and isobornyl acrylate (IBOA) content on PSA performance were comprehensively investigated by measurement of their rheological, thermal, and adhesive properties. In particular, rheological characterization was accomplished by several analytical methods, such as UV rheology, frequency sweep, stress relaxation, and temperature ramp tests, to understand the effect of the UV curing process and IBOA content on the viscoelastic behavior of acrylic PSAs. The slow-cured samples were observed to form more tightly crosslinked networks compared to the fast-cured. On the other hand, at high loading levels of IBOA, in the case of slow curing, the sample exhibited a contrasting trend, having the shortest stress relaxation time and the highest energy dissipation; this was due to molecular chain scission occurring in the crosslinked polymer during UV polymerization. Consequently, we successfully demonstrated the influence of monomer composition of acrylic PSAs, and that of curing conditions employed in UV polymerization. This study provides valuable insights for the development of crosslinked polymer networks of acrylic PSAs for flexible display applications.
通过分别采用高强度和低强度紫外线辐射，在快速固化和慢速固化这两种不同的固化条件下，通过紫外线聚合制备了丙烯酸类压敏胶粘剂（PSA）。通过测量其流变学、热学和粘合性能，全面研究了固化条件和丙烯酸异冰片酯（IBOA）含量对PSA性能的影响。特别是，通过几种分析方法，如紫外线流变学、频率扫描、应力松弛和温度斜坡试验，完成了流变学表征，以了解紫外线固化过程和IBOA含量对丙烯酸类PSA粘弹性行为的影响。观察到与快速固化的样品相比，慢速固化的样品形成了更紧密交联的网络。另一方面，在高IBOA含量水平下，在慢速固化的情况下，样品呈现出相反的趋势，具有最短的应力松弛时间和最高的能量耗散；这是由于在紫外线聚合过程中交联聚合物中发生了分子链断裂。因此，我们成功地证明了丙烯酸类PSA单体组成以及紫外线聚合中使用的固化条件的影响。这项研究为用于柔性显示应用的丙烯酸类PSA交联聚合物网络的开发提供了有价值的见解。
