纳米SiO2接枝聚合改性及在EVOH中的应用

以硅烷偶联剂3-(甲基丙烯酰氧)丙基三甲氧基硅烷(KH570)对纳米二氧化硅(SiO2)进行表面处理,通过分散聚合工艺分别制得SiO2-g-KH570-g-PS、SiO2-g-KH570-g-PMMA和SiO2-g-KH570-g-PAN,采用熔融共混法制备了乙烯-乙烯醇共聚物(EVOH)/纳米SiO2复合材料(5%(...

Graft Polymerization Modification and Application of Nano-SiO2

Nanosilica（nano-SiO₂）,modified by 3-trimethoxysilyl-propyl-methacrylate（KH570）,was used to prepare SiO₂-g -KH570-g-PSt、SiO₂-g-KH570-g-PMMA and SiO₂-g-KH570-g-PAN by dispersion polymerization process.The modified nano-SiO₂ was used to prepare the ethylene-vinyl alcohol copolymer（EVOH） /nano-SiO₂ composites,and the composites were blown to film.The nano-SiO₂ and composites were characterized by Fouriertransform infrared（FT-IR）,transmission electron microscope（TEM） and scanning electron microscope（SEM） and the properties of composites were tested.The results show that:chemical bonds are formed between nano-SiO₂ and KH570,and graft polymerization is occurred between polystyrene（PS）,polymethyl methacrylate（PMMA）, polyacrylonitrile（PAN） and nano-SiO₂.The properties of films which were prepared by the nano-SiO₂ grafted with polymers have been improved greatly.In contrast to the EVOH/SiO₂ composites prepared with unmodified SiO₂（5% SiO₂）,the tensile strength of the EVOH/SiO₂ composites prepared with modified nano-SiO₂ increases by 21.8%, and the moisture permeance factor and the oxygen permeability coefficient of those decreases by 12.3%and 19% respectively.The transmittance is 75.8%and the haze is 13.65%.