In this paper,with polyvinyl alcohol and silver nitrate as raw material,different content of silver nitrate was dissolved in PVA solution,then the AgNO3/PVA composite films were prepared by solution casting. After AgNO3/PVA composite films were heated,under the hydroxyl of PVA, silver nitrate was reduced to silver particles which make the films conductivity. The thermal properties of PVA/AgNO3 film and the morphology and structure of the film after heat treatment were studied by thermogravimetry a-nalysis,differential scanning calorimeter,scanning electrical microscopy,X-ray diffraction. The results indicated that the PVA/Ag-NO3 composite films presented an exothermic peak between 150℃ and 200℃ which showed silver nitrate was reduced silver parti-cles during the temperature. Ag nanoparticles were prepared after heat treatment and the average sizes of silver particles were 100 nm. As the existence of Ag,with increasing heat temperature electric conductivity increase several 5 order of magnitude from 150 to 175 ℃ which indicated that the improvement of heat treatment temperature and time reduced Ag effectively and conductivity in-creased with silver particles closing to each other.%以硝酸银和聚乙烯醇(PVA)为原料,将不同浓度的硝酸银溶解在PVA水溶液中,通过溶液成膜法制备了含有硝酸银的薄膜.对薄膜加热,硝酸银在聚乙烯醇羟基作用下还原成银粒子,从而使薄膜具有导电性.通过热失重分析仪、差示扫描量热仪、扫描电子显微镜、X射线衍射等方法研究了薄膜热性能和热处理后薄膜表面形貌和结构分析.结果表明,AgNO3/PVA复合薄膜在150~200℃之间出现一个放热峰,表明硝酸银在此温度区间被还原成银粒子.通过热处理方式制备出纳米银,平均尺寸在100 nm左右.由于银粒子的存在,使薄膜具有导电性,当热处理温度从150℃升至175℃,薄膜表面电导率从3.16×10-9 S·cm-1增加至1.76×10-4 S·cm-1,增加了5个数量级,表明热处理时间和处理温度的提高使银粒子的还原更加充分,粒子之间彼此靠近导致导电性提高.
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