基于儿茶酚交替共聚物的干湿态双高效胶黏剂材料

High-performance Adhesive Material at Dry and Under-seawater Conditions Based on Catechol-functionalized Alternating Copolymer

以多巴胺(DA)和双酚A型环氧树脂(BAER)进行氨基-环氧点击化学反应,合成了儿茶酚功能化交替共聚物聚(多巴胺-alt-双酚A型环氧)[P(DA-a-BAER)].以FeCl3为交联剂,研究了交联剂用量对聚合物在干态及水下环境中黏接性能的影响.结果表明,该聚合物可以在干态及水下环境中对多种基材进行黏接.以不锈钢基材为例,在干态条件下,当Fe^3+与儿茶酚基团的摩尔比为1:3时,黏接强度最高,为(3.03±0.68)MPa;在水下环境中,当Fe^3+与儿茶酚基团的摩尔比为1:6时,黏接强度最高,为(0.65±0.10)MPa.拉曼光谱(Raman)和紫外-可见光吸收光谱(UV-Vis)分析结果表明,Fe^3+与儿茶酚基团可通过配位交联和氧化交联的方式增大胶体强度,从而提高黏接强度.

A novel catechol-functionalized alternating copolymer, poly( dopamine-alt-bisphenol A epoxy resin) [P( DA-a-BAER) ],was synthesized from the copolymerization between dopamine( DA) and bisphenol A epoxy resin( BAER) monomers via an epoxy-amino click reaction. The resultant alternating copolymer was used as an adhesive material,of which the bonding performances both at dry and under-seawater conditions were investigated with the usage of FeCl3 as cross-linker. The results showed that P( DA-a-BAER) could achieve excellent bonding strength on various substrates both at dry and under-seawater conditions. Taking stainless steel as an example,a bonding strength of( 3. 03±0. 68) MPa was achieved at atmospheric situation with a 1 ∶ 3 molar ratio of Fe3+ to catechol groups;an under-seawater bonding strength of( 0. 65±0. 10) MPa was achieved when the molar ratio of Fe3+ to catechol groups reached 1 ∶ 6. The crosslinking mechanism of Fe3+ was studied by Raman spectrometry and UV-Vis absorption spectrometry,demonstrating that catechol moieties underwent oxidation crosslinking and coordination crosslinking processes. As a result,the cohesion strength of the polymer was enhanced,leading to a high bonding strength.