Alrefai Masa, Maric Milan
Dept. of Chemical Engineering, McGill University 3610 Rue Universite Montreal QC H3A 0C5 Canada
RSC Adv. 2025 Jan 3;15(1):312-322. doi: 10.1039/d4ra08072f. eCollection 2025 Jan 2.
Compositions of ethylene glycol dicyclopentenyl ether methacrylate (EGDEMA), a vegetable oil based alkyl methacrylate (C13MA), and furfuryl methacrylate (FMA) were terpolymerized for dual-crosslinked networks with tailored mechanical and thermal properties. Specifically, initiators for continuous activator regeneration (ICAR) atom transfer radical polymerization (ATRP) afforded materials with tailored glass transition temperature ( ) and incorporation of furan and norbornene functionalities within a single chain. The terpolymer with high furan and norbornene functionality (Ter2: = 0.42, = 0.46, = 0.12) is crosslinked to form single-crosslinked reversible networks with 1,1'-(methylenedi-4,1-phenylene)bismaleimide (BM) Diels-Alder (DA) chemistry and dual-crosslinked networks incorporating additional non-reversible thiol-ene crosslinks. The reactions were photo-initiated using 254 nm UV light with BM : FMA molar ratios of 0.1 and 0.2 for both systems. FTIR analyses for crosslinked Ter2 samples confirmed the successful formation of DA and thiol-ene adducts, while DSC confirmed the reversibility of the DA reaction. A terpolymer with higher C13MA composition (Ter3: = 0.75, = 0.17, = 0.08) was similarly crosslinked in single and dual crosslinked networks with BM : FMA of 0.1 and 0.2. Crosslinking efficiency was evaluated for both single and dual crosslinked networks with a BM : FMA = 0.1 by comparing thermal and UV curing methods, with UV curing proving more effective for dual-crosslinked systems, leading to increased gel content (71% with UV compared to 61% thermally) and improved material properties. FTIR and DSC results confirmed the formation of the DA adducts and the reversibility of the DA reaction. The terpolymers were further analyzed for adhesive applications through rheological testing. These studies demonstrated that the incorporation of thiol-ene crosslinking alongside Diels-Alder crosslinking offers a balanced combination of reversible and permanent bonds, resulting in materials with enhanced mechanical strength, thermal stability, and functional versatility that are suitable for applications such as recyclable adhesives.
将乙二醇二环戊烯基醚甲基丙烯酸酯（EGDEMA）、植物油基甲基丙烯酸烷基酯（C13MA）和甲基丙烯酸糠酯（FMA）的组合物进行三元共聚合，以形成具有定制机械和热性能的双交联网络。具体而言，连续活化剂再生引发剂（ICAR）原子转移自由基聚合（ATRP）得到了具有定制玻璃化转变温度（ ）且在单链中引入呋喃和降冰片烯官能团的材料。具有高呋喃和降冰片烯官能度的三元共聚物（Ter2： = 0.42， = 0.46， = 0.12）通过1,1'-（亚甲基二-4,1-亚苯基）双马来酰亚胺（BM）狄尔斯-阿尔德（DA）化学交联形成单交联可逆网络，并通过引入额外的不可逆硫醇-烯交联形成双交联网络。对于两个体系，反应均使用254 nm紫外光光引发，BM与FMA的摩尔比为0.1和0.2。对交联的Ter2样品进行的FTIR分析证实了DA和硫醇-烯加合物的成功形成，而DSC证实了DA反应的可逆性。具有较高C13MA组成的三元共聚物（Ter3： = 0.75， = 0.17， = 0.08）同样在BM与FMA为0.1和0.2的单交联和双交联网络中进行交联。通过比较热固化和紫外固化方法，对BM与FMA = 0.1的单交联和双交联网络的交联效率进行了评估，结果表明紫外固化对双交联体系更有效，导致凝胶含量增加（紫外固化时为71%，热固化时为61%）且材料性能得到改善。FTIR和DSC结果证实了DA加合物的形成以及DA反应的可逆性。通过流变学测试对三元共聚物在胶粘剂应用方面进行了进一步分析。这些研究表明，硫醇-烯交联与狄尔斯-阿尔德交联的结合提供了可逆键和永久键的平衡组合，从而得到具有增强机械强度、热稳定性和功能通用性的材料，适用于可回收胶粘剂等应用。
