Preparation of IPN-type carbon black nano-composite and its responsibility agains solvent vapor

为了制备一种新型的抗溶剂气敏传感器，研究了互穿网络（IPN）型纳米复合材料的电阻响应特性。此外，还研究了结晶聚合物接枝炭黑复合材料在正己烷中对溶质的电阻响应性。（ε-己内酯）（PCL），聚（乙二醇）（PEG），和聚己二酸乙二醇酯通过端羟基与表面羧基的直接缩合反应，成功地将其接枝到炭黑表面，使用N，N ′-二环己基-碳二亚胺作为缩合剂。将聚合物接枝炭黑与结晶性聚合物共混，制备了均匀的电阻器，并在交联剂存在下，通过CL阳离子开环聚合制备了聚乙烯接枝炭黑/聚己内酯互穿网络（IPN）型纳米复合材料。 ...更多信息 交联PB接枝炭黑。由于基体聚合物的交联作用，复合材料对溶剂蒸气不敏感，在干燥的己烷中复合材料的电阻几乎没有变化，而在含有接枝聚合物良溶剂的己烷中，由结晶聚合物接枝炭黑制备的纳米复合材料的电阻显著增加。例如，PCL接枝炭黑复合材料在含有氯仿、四氢呋喃和乙醇的己烷中的电阻增大，在干燥的己烷中的电阻恢复到初始值，复合材料电阻的对数与氯仿在己烷中的浓度成线性关系。这是由于接枝聚合物对良溶剂的溶质吸附，使其结晶结构发生变化，从而使炭黑粒子间的间隙发生微小变化，使炭黑粒子间的间隙发生微小变化。少

To prepare a novel gas sensor against various solvent vapor, the responsibility of electric resistance of inter penetrating network (IPN)-type nano-composite was investigated. In addition, the responsibility of electric resistance of composite from crystalline polymer-grafted carbon black against solute in hexane was also examined.Crystalline polymers, such as polyethylene (PB), poly(epsilon-caprolactone) (PCL), poly(ethylene glycol) (PEG), and poly(ethylene adipate) (PEA) were successfully grafted onto carbon black surface by direct condensation of terminal hydroxyl groups of these polymers with carboxyl groups on the sufface using N,N'-dicyclohexyl-carbodiimide as a condensing agent. A uniform resistor was readily pre-pared by mixing the the polymer-grafted carbon black with crystalline polymer.The preparation of inter penetrating network (IPN)-type nano-composite of PE-grafted carbon black with PCL was achieved by cationic ring-opening polymerization of CL in the presence of crossli … More nked PB-grafted carbon black. No responsibility of the composite against solvent vapor, however, was observed because of crosslink-ing of matrix polymer.Although the change of electric resistance of the composite hardly observed in dry hexane, the electric resistance of a nano-composite prepared from crystalline polymer-grafted carbon black drastically increased in hexane containing good solvent of grafted polymer. For example, the electric resistance of composite from PCL-grafted carbon black increased in hexane containing chloroform, tetrahydrofuran, and alcohol, and returned to initial resistance when the composite was transferred in dry hexane.It was found that the logarithm of electric resistance of the composite is linearly proportional to chloroform concentration in hexane. This indicates that the composite can be also applied as a novel solute sensor and a densitometer.This is due to a slight change of gaps between carbon black particles by the change of crystalline structure based on the absorption of solute of a good solvent of grafted polymer. Less