短氟碳链含氟硅烷偶联剂及其疏水涂层的构建

以三氟丙基甲基环三硅氧烷(D3F)、二甲基氯硅烷、甲基二氯硅烷、乙烯基三甲氧基硅烷(VTMS)为主要原料,通过阴离子开环聚合和硅氢加成反应合成了一系列短氟碳链含氟硅烷偶联剂。载玻片表面经纳米二氧化硅溶胶涂膜和硅烷偶联剂表面修饰得到疏水涂层。探究了不同硅烷偶联剂对于涂层疏水性、附着力、硬度、透过率等性能的影响。结果表明,同类型含氟硅烷偶联剂中氟含量越大,其修饰的涂层接触角越大;相似相对分子质量及氟含量情况下,直链型含氟硅烷偶联剂修饰的涂层疏水性优于支链型修饰的涂层。经含氟硅烷偶联剂修饰的疏水涂层中,接触角最大的是由聚合度为9的支链型含氟硅烷偶联剂(DF3)修饰的涂层,可达141.6°。疏水涂层的附着力均达1级,硬度均达H,可见光透过率高于82.9%,具有良好的自清洁性能。

Synthesis of Fluoride-containing Silane Coupling Agents with Short Fluorocarbon Chains and their Application in Hydrophobic Coating Construction

Several fluoride-containing silane coupling agents with short fluorocarbon chains were synthesized via the anionic ring-opening polymerization and hydrosilylation reaction using trifluoropropylmethylcyclotrisiloxane(D3F), dimethylchlorosilane, methyldichlorosilane and vinyltrimethoxysilane(VTMS) as reactants. The substrate on the glass plate was prepared by spin-coating of nano-silica sol, and the hydrophobic coating was obtained after the modification of silane coupling agents. The effects of silane coupling agents on the hydrophobicity, adhesion, hardness and transmittance of the coatings were investigated. The results showed that for the same type fluoride-containing silane coupling agents, the contact angle increased with the fluorine content in the agents. For the fluoride-containing silane coupling agents which had the similar molecular weight and fluorine content, the coating modified by the linear type coupling agent was more hydrophobic than the one modified by the branched type. Among the fluoride-containing silane coupling agents in this work, the coating modified by the branched type with a degree of polymerization of 9(DF3) showed the biggest contact angle, about 141.6°. The adhesion level of the hydrophobic coatings in all cases reached to level 1 and the hardness reached to H, while the visible light transmittance was higher than 82.9%. The hydrophobic coatings also had good self-cleaning property.