| Products made of PVC was everywhere in our life, but the capacity of PVC was surplus seriously since 2008 for weak demand, how to make the property of PVC powerful and exploring new application field were getting more and more urgent. In recent years, the study of graphene has become a hotpot for its good electrochemical property, mechanical property and thermal stability. In this paper, in order to widen the appllication range, graphene was alloyed into PVC. However, just for the integrated structure and stable chemical property of graphene, it can be hardly dispersed into polymers. In this thesis,APTS was utilized to react with the oxygen-containing functional group on the surface or edge of graphene oxide to enhance the compatibility between inorganic nano-materials and organic polymers, and the functionalization process was tracked by FTIR and UV-Vis. Through TGA and contact angel tests, thermal stability and wettability were also studied. The main work were as follows:(1)As the modifying agent, APTS was successfully anchored on the surface of graphene oxide, the process of which was tracked by FTIR spectrum and UV-Vis spectrophotometer. The FTIR spectrum results showed significant changes in the range of 4000cm-1 to 600cm-1. Peak at 2929cm-1 emerged newly represented amino groups,and became intenser and intenser with reaction time. The increase in the intensity of the broad band around 1061cm-1 was observed, which corresponded to Si-O-Si, Si-O-C and C-O-C, among which the absorption peaks of Si-O-C and C-O-C were covered by the intense absorption peaks of Si-O-Si. Meanwhile, some by-products produced during the period of reaction, such as silanol, DCU, the UV-Vis spectrophotometer results indicated that the reaction ending time was 28 h. Moreover, the grafting ratio of graphene oxide was calculated as 12.175%, which indicated that APTS was anchored as net.(2) Solution blended method was used to manufacture GO/PVC and APTS-GO/PVC nanocomposites with different contents, moreover, the LOI value, combustion heat and char structure were tested by oxygen index apparatus, bomb calorimeter and FESEM respectively. The results showed that LOI value increased with the addition of nanofiller, the incorporation of GO/PVC nanocomposites with 1.5wt% of GO displayed 35 of LOI value and 35.8 for APTS-GO/PVC membrane, therefore, the best additive amount was 1.5wt% for APTS-GO to save cost and industrial product. Nevertheless, it seemed that the addition of GO or APTS-GO impacted little on combustion heat, it's about 21MJ/Kg for both PVC membrane and nanocomposites; The images of char showed that the char surface of APTS-GO/PVC was continuous and tight, the holes got much smaller, which could inhibit the overflow of degradation products and combustible gas for further burning.(3) The thermostability of PVC, GO and APTS-GO were measured by thermogravimetric analysis(TGA), TGA curves showed that the decomposition of PVC membrane was divided into two stages while GO and APTS-GO has only one stage,moreover, GO decomposed at lower temperature for its –OH,-COOH, C-O-C on the surface and had lower carbon yield, while APTS-GO decomposed slowly, compared with PVC, GO, the carbon yield of APTS-GO were improved markedly with up to 45.963% and 44.199% respectively. For nanocomposites, the TGA results showed that PVC membrane decomposed at 251.1?, while the initial degradation temperature of 2.5wt%GO/PVC and 2.5wt% APTS-GO/PVC improved 4.8% and 7.5% respectively. Furthermore, it could be seen from the figure of carbon yield, compared with pure PVC, GO/PVC and APTS-GO/PVC had lower weight loss, and the char yield of APTS-GO/PVC improved 13.35%. What's more, the activation energy increased with the content of nanofiller. At last, the cross-sectional images of composite material indicated that the GO/PVC got unstable after electron bombardment but APTS-GO/PVC was always steady during the whole testing period, besides, its surface was flat and dispersed well, but the GO/PVC got reunited obviously.(4) The contact angel on the surface of GO/PVC and APTS-GO/PVC nanocomposites was tested by contact angel apparatus, it was found out that the contact angel values decreased with respect to the increasing content of nanofiller, moreover,the surface wettability of GO/PVC and APTS-GO/PVC reached the best at the content of 2.5wt%. What's more, the contact angel of pure PVC membrane, 0.5wt%GO/PVC and 0.5wt%APTS-GO/PVC were 86.8?, 82.5?and 80.5? respectively with respect to water, however,it decreased to 56.1? and 48.4? for GO/PVC and APTS-GO/PVC respectively with the content of 2.5wt% for nanofiller. Meanwhile, the tendency of surface energy calculated by OWRK and Acid base method proved to be coincident, the value got higher and wettability got enhanced. |
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