尿素功能化石墨烯及其对酚醛树脂性能的影响

Preparation of Functionalized Graphene with Urea and Its Effects on Properties of Phenolic Formaldehyde

采用尿素对氧化石墨烯(GO)进行化学修饰,一步法合成了可稳定分散在乙醇中的尿素功能化石墨烯(UFG),同时采用溶液共混法制备了酚醛树脂(PF)/UFG复合材料。X射线衍射(XRD)、傅立叶变换红外光谱(FTIR)、X射线光子能谱(XPS)、热重(TG)分析和扫描电子显微镜(SEM)等分析表明,尿素对GO同时起到了接枝改性和还原的作用,所得UFG在PF中可均匀分散,并且可提高PF的残炭率,当UFG质量分数仅为0.1%时900℃残炭率较纯PF可提高4%。在该含量下,PF/UFG/CF复合材料的弯曲弹性模量较未加UFG时可提高13.0%,线烧蚀率和质量烧蚀率没有明显变化。

A novel chemical functional graphene （UFG） was achieved with urea as modified agent in one step,which could disperse homogeneously in ethanol solvent. Meanwhile the phenolic formaldehyde （PF）/UFG composites were prepared by solution mixing with different amount of UFG. XRD,FTIR,XPS,TG and SEM characterizations show that GO is grafting-modified and reduce simultaneously by urea. After adding UFG, it can be dispersed uniformly and stably in PF matrix,the char yielding of PF/UFG composites with only 0.1% amount UFG at 900℃increases by 4% comparing with pure PF. With the content theflexural modulus of PF/UFG/CF composite increases by 13.0% comparing with PF/CF composite. There is no obvious changes about the linear ablative rate and mass ablative rate.