碱处理对PVDF/CB复合导电薄膜气敏响应性能的影响

Effect of Alkali Treatment on Gas Sensing Response of PVDF/CB Composite Conductive Films

基于分子复合设计原理,制备了一种新型的炭黑填充聚偏氟乙烯(PVDF)气敏导电复合材料(PVDF/CB),并用KOH/乙醇溶液对PVDF/CB导电复合薄膜进行修饰改性,阐明了复合薄膜的微观结构与气敏响应行为之间的关系。实验结果表明,经过KOH/乙醇溶液处理,降低了导电膜的响应选择性和响应强度,采用傅立叶变换红外光谱法(FT-IR)实验证明,随着KOH/乙醇溶液用量提高,PVDF的分子结构得以改变。采用差示扫描量热分析法(DSC)实验证明,非晶区聚集态的变化对聚合物膨胀效应和导电膜响应性能产生了影响。

Based on the principle of molecular composite design,a new carbon black filled polyvinylidene fluoride(PVDF)gas sensitive conductive composite(PVDF/CB)was prepared,and the PVDF/CB conductive composite film was modified with KOH/ethanol solution.The relationship between the microstructure of the composite film and the gas sensitive response behavior was clarified.The experimental results showed that the response selectivity and response strength of the conductive film were reduced after KOH/ethanol solution treatment.Moreover,Fourier transform infrared spectroscopy(FT-IR)experiments showed that the molecular structure of PVDF changed with the increase of the amount of KOH/ethanol solution.In addition,differential scanning calorimetry(DSC)experiments showed that the change of aggregation state in amorphous region affected the expansion effect of polymer and the response performance of conductive film.