纳米SiO_2对酚醛环氧树脂改性研究

以双酚A及甲醛为基本原料,加入纳米SiO2制备了纳米氧化硅改性酚醛树脂预聚体,其与环氧树脂继续共聚得到纳米氧化硅改性酚醛环氧树脂。通过红外光谱、粒径分布仪、X射线衍射、扫描电镜分析及涂膜性能测试对产物进行了研究和表征。结果表明,纳米氧化硅均匀分布在共聚物中,说明纳米氧化硅中的羟基参与了酚醛的共聚;纳米SiO2的加入对酚醛环氧树脂的结构无太大影响。与未改性醛醛环氧树脂比较,纳米SiO2的加入可有效提高涂层的耐水煮、黄变、硬度、吸水率及耐盐水腐蚀性。

Study on nano-silica modified phenolic epoxy resins

The nano-silica modified phenolic resin pre-polymer was prepared by using bisphenol A and formaldehyde as basic materials and adding nano-silica.The nano-silica modified phenolic resin was obtained by copolymerization of the pre-polymer and epoxy resins.The product was investigated and characterized by IR,particle size distribution,scanning electron microscope and property test of the coating films.The results showed that the nano-silica uniformly dispersed in the copolymer and it indicated that the hydroxy groups of nano-silica took part in the copolymerization of phenolic resins.The addition of nano-silica had little effect on the structure of phenolic epoxy resins.The water boiling resistance,yellowing temperature,hardness,water absorption rate and saline corrosion resistance of the coating film could be improved effectively by adding the nano-silica compared with the unmodified phenolic epoxy resins.