Abstract:

A series of diblock copolymers,poly (butyl methacrylate-co-glycidyl methacrylate)-b-poly-dodecafluoroheptyl methacrylate(P(BMA-co-GMA)-b-PDFHMA,BGF),containing fluorinated acrylates and glycidyl methacrylate (GMA) polymer with controlled structure were synthesized by means of the initiators for continuous activator regeneration atom transfer radical polymerization (ICAR-ATRP). The diblock copolymers was mixed with epoxy resin to prepare self-stratifying coatings. When the 10% content of fluorine-containing resin having a number average molecular weight of 5.3k-b-2.3k and GMA content of 20% was added, fourier transform infrared spectroscopy (FT-IR) and energy dispersive spectrum-electron scanning microscopy (EDS-SEM) testing revealed that parts of fluorinated acrylate blocks migrated to the surface of coating. Fluorine element of the film had good self-migration effect, and the fluorine content in the surface layer reached more than 20%. The increasingly introduction of GMA could further restrict the migration of fluorine-containing resin. UV resistant testing indicated that gloss retention rate of self-stratifying coating is much higher than the pure epoxy coating. The resistance to yellowing perforamance is not changed obviously. Water contact angle and salt spray testing revealed that addition of 10% diblock copolymer could increase the water contact angel to above 100°. The anticrrosive performance of all self-stratifying coatings were improved. Blistering was surpressed effectively. The basic mechanical properties of the coating film was not affected when the addition of diblock copolymer was less than 4%, but the gloss was decreased.

Key words: atom transfer radical polymerization, fluorinated acrylate, block copolymer, epoxy resin, self-stratifying coating

摘要：

利用引发剂连续再生催化剂原子转移自由基聚合(ICAR-ATRP)合成了一系列结构可控的含有含氟丙烯酸酯和甲基丙烯酸缩水甘油酯(GMA)的两嵌段丙烯酸酯聚合物,即聚(甲基丙烯酸丁酯-co-甲基丙烯酸缩水甘油酯)-b-聚甲基丙烯酸十二氟庚酯[P(BMA-co-GMA)-b-PDFHMA,BGF]。将嵌段聚合物与环氧树脂混合制备自分层涂料。傅里叶变换红外光谱(FT-IR)和扫描电子显微镜-能谱分析仪(SEM-EDS)测试表明,当两嵌段聚合物中P(BMA)-co-GMA与PDFHMA的相对分子质量分别为5 300和2 300、GMA结构单元相对分子质量占总相对分子质量的20%,且BGF用量为10%时,漆膜固化过程中含氟嵌段聚合物可以部分迁移到漆膜表面,共混漆膜氟元素自迁移效果较好,表层氟含量达到20%以上,且增加含氟树脂中GMA含量时漆膜氟元素迁移效果下降;耐紫外老化性测试结果表明,含氟树脂的加入使得漆膜的光泽保持率更好,耐黄变性变化不大;水接触角和耐盐雾性测试结果表明,相对纯环氧树脂,加入10%含氟嵌段聚合物使漆膜的水接触角均提高到了100°以上,自分层漆膜的耐盐雾性都有一定提高,可以有效防止漆膜的起泡。嵌段聚合物的加入量低于4%时,对漆膜的基本力学性能没有影响,但光泽有一定下降。

关键词: 原子转移自由基聚合, 含氟丙烯酸酯, 嵌段聚合物, 环氧树脂, 自分层涂料

CLC Number: 

• TQ637