Study On Preparation And Properties Of PMMA/ATO Conductive Composites

In this work,a kind of PMMA(polymethylmethacrylate) based conductive composite filled with nanoscaled ATO(antimony doped tin oxide) powder was prepared via in-situ polymerization. The influences of ATO content and milling-time on the properties of the composites were studied. We also investigated the effects of the third component,including styrene-maleic anhydride copolymer and nano-SiO2,on the conductive structure formation of PMMA/ATO composites. The main works and conclusions were shown as follows:(1) Firstly,a small quantity of ATO powders were modified by silane coupling agent and treated by a ball mill,in order to determine the modifying conditions. According to the results of a laser grain size analyzer and SEM test,the ATO powders was successfully dispersed by using silane coupling agent KH570(3% content) and milling ten hours.(2) The ATO powders were modified according to the procedure mentioned above.FTIR results showed that there were both physical and chemical effects on ATO powders, which were modified by silane coupling agent KH570. PMMA based conductive composites filled with different mass fraction and milling-time of nano-ATO was prepared via in-situ polymerization. We also introduced the third component,including styrene-maleic anhydride copolymer and nano-SiO2 in the composites.(3) According to SEM observation on PMMA/ATO composite,ATO particles were dispersed in PMMA matrix homogeneously , but there are also some conglomerations exist. The addition of third phase SMA could forming conductive networks obviously in PMMA matrix;The results of conductivity testing revealed that increasing the mass fraction of nano-ATO,prolonging the milling-time of ATO and adding the third phase SMA into PMMA/ATO could significantly improving the conductivity of the composites;TG-DTA results showed that with the addition of ATO, the main decomposed peak of PMMA/ATO composites shifts to higher temperature and the residual amount increases, which indicated that the thermal stability was improved. The addition of SMA have no effects on the thermal stability;DMA results showed that with the increasing of nano-ATO content,the storage modulus of the composites was improved,while the glass transition temperature was reduced.