Preparation of Inorganic/Organic Nano Composite Sensor by Sol-Gel Process in the Presence of Both Recycled Polymers and Polymer-Grafted Carbon Nanotube

我们研究了一种新型的无机/有机纳米复合材料的制备在回收的聚合物和聚合物接枝的无机纳米粒子，如炭黑，碳纳米管，和碳微线圈的存在下，通过溶胶-凝胶过程。利用纳米粒子表面的羟基作为引发位点，实现了聚苯乙烯和聚酯的表面接枝。在聚合物接枝炭黑和碳纳米管、回收聚苯乙烯和聚对苯二甲酸乙二醇酯共存的情况下，进行苯基三乙氧基硅烷的溶胶-凝胶反应，获得了无机纳米颗粒和回收聚合物均匀掺入的硅胶/无机纳米颗粒复合材料薄膜。我们还研究了复合材料在各种溶剂中的气敏特性，以便将这些复合材料应用于新型的气敏传感器。硅胶/炭黑复合材料的吸附性能随炭黑表面接枝聚合物链和回收聚合物链对所用溶剂的溶解度而变化。在炭黑表面接枝聚合物链和回收聚合物链的良溶剂的情况下，硅胶/炭黑复合物选择性地吸附溶剂蒸气。复合材料的电阻对接枝聚合物链和回收聚合物链的良溶剂蒸气也非常敏感：碳纳米管表面的接枝聚合物链和回收聚合物链的电阻在良溶剂蒸气中急剧下降，但它们在不良溶剂蒸气中变化不大。

We examined the preparation of a novel inorganic/organic nano composite by sol-gel process in the presence of both recycled polymers and polymer-grafted inorganic nano-particles, such as carbon black, carbon nanotube, and carbon microcoil. The surface grafting of polystyrene and polyester was achieved by use of hydroxyl groups on the nano-particle surface as initiating sites. When sol-gel reaction of phenyl-triethoxysilane was carried out in the coexistence of the polymer-grafted carbon black and carbon nanotube, and recycled polystyrene and poly(ethylene terephthalate), thin films of silica gel/inorganic nano-particle composite in which both the inorganic nano-particles and recycled polymers were uniformly incorporated were obtained. We examined also the vapor-sensing properties of the composites in the various solvents in order to apply these composites to a novel vapor sensor. The vapor adsorption properties of the silica gel/carbon black composite varied with the solubility of grafted polymer chains on the carbon black surface and the recycled polymer chains toward the applied solvent. In the case of the good solvent for both the grafted polymer chains of the carbon black surface and the recycled polymer chains, the silica gel/carbon black composite selectively adsorbed the solvent vapor. Electric resistance of the composite was also very sensitive to the vapor of the good solvent for the grafted and recycled polymer chains: the electric resistance drastically decreased in vapor of good solvent for both the grafted polymer chains of the carbon nanotube surface and the recycled polymer chains, but it sparingly changed in vapor of poor solvent for both of them.