分子结构对含氟丙烯酸酯嵌段聚合物/环氧树脂自分层涂料的影响

Influence of Fluorine-Containing Acrylate Block Polymer on the Stratification Behavior of Its Self-Stratifying Coating with Epoxy Resin

利用电子转移再生催化剂原子转移自由基聚合(ARGET-ATRP)合成了一系列不同共聚组成及相对分子质量的聚甲基丙烯酸丁酯-b-聚甲基丙烯酸十二氟庚酯(PBMA-b-PDFHMA)嵌段共聚物,并将其与环氧树脂E-20共用制备了混合涂料。基于各个组分及基材的表面能对混合涂料的分层行为进行了理论预测。通过傅里叶变换红外光谱、扫描电子显微镜证实了部分涂料在固化阶段发生了明显的分层行为。当相对分子质量较小时,含氟链段的含量对分层行为影响不大;当相对分子质量较大,含氟链段含量高时,自分层行为才容易发生。当含氟嵌段聚合物相对分子质量为1×10^(4),含氟链段占嵌段共聚物质量的20%时,自分层涂料漆膜分层情况最好且水接触角达到108°。当含氟嵌段聚合物相对分子质量为3×10^(4),含氟链段含量为20%时,其综合性能最优。

Electron transfer regeneration catalyst atom transfer radical polymerization(ARGET-ATRP)was used to synthesize a series of poly(butyl methacrylate-b-dodecafluoroheptyl methacrylate)(PBMA-bPDFHMA)with different copolymerizaton compositions and molecular weight,and which were used with epoxy resin E-20 to prepare self-stratifying coatings.The stratification behavior of prepared coatings was theoretically predicted based on the surface energy of each component and the substrate.FT-IR and SEM confirm that some coatings have obvious stratification behavior at the curing stage.When the molecular weight is low,the content of fluorine-containing segments has little effect on the stratification behavior;when the molecular weight is high,the self-stratification behavior easily occurs when the content of fluorine-containing segment is high.When the molecular weight of the fluorine-containing block polymer is 1×10^(4) and the content of fluorine-containing segment is 20%,the self-stratification result of the self-stratification coating is the best and the water contact angle reaches 108°.When the molecular weight of the fluorine-containing block polymer is 3×104 and the fluorine-containing segments account for 20% of the block copolymer mass,its comprehensive performance is optimal.