摘要
采用不同醇解度的聚乙烯醇（PVA）和硝酸银（AgNO3）为原料,通过溶液成膜法制备了在固相具有热致变性能的导电PVA/AgNO3复合薄膜.采用FTIR表征了各种醇解度的PVA与Ag＋之间的络合作用.通过TG、SEM、X-射线衍射、X射线能谱（EDS）等方法研究了不同醇解度的PVA/AgNO3复合薄膜的热性能和热处理后薄膜表面形貌和结构,结果表明：不同醇解度的PVA/AgNO3复合薄膜在160～200℃均有一明显失重峰;随着醇解度增加,SEM显示热处理后纳米银粒子尺寸减小;实验发现在温度为170 ～ 200℃时,醇解度为80％、88％、92％的PVA/AgNO3复合薄膜其表面电阻率能从300 ～ 500 kΩ突然降低到5～20 Ω（降低4～5个数量级）,而醇解度为97％的PVA/AgNO3复合薄膜表面电阻率不能发生突变,反而升高.这种具有独特电阻率-温度特性的薄膜在热敏电阻或温度传感器等方面有潜在应用.
Solution casting technique was used to prepare the PVA/AgNO3 composite films with thermal-electrical property in the solid state by using PVA with different alcoholysis degree and AgNO3 as the raw materials. The complexation of PVA with different alcoholysis degree and Ag · was characterized by FTIR. The thermal properties of the films were characterized by TG and the morphology and structure of PVA/AgNO3 films after heat treatment were studied by scanning electrical microscopy （SEM）, X-ray diffraction （XRD） and EDS. The results showed that all the AgNO3-doped PVA films presented earlier degradation at 160 -200 ℃. SEM photos showed that the size of generated Ag particles decreased with increasing alcoholysis degree of PVA. During heat treatment, the surface electrical resistivity of PVA/AgNO3 composite films for alcoholysis degree of 80% , 88% and 92% could sharply dropped from 300 -500 kΩ to 5 -20Ω（4 -5 order） at 170 -200 ℃. However, for the high alcoholysis degree of 97% , the surface electrical resistivity of the film could not decrease but increase. Moreover, these films with the distinct thermal-electrical property had a promising application as thermistor or temperature sensor.
出处
《塑料》
CAS
CSCD
北大核心
2016年第1期7-11,共5页
Plastics
