A novel sensor for organic solvent vapors based on conductive amorphous polymer composites: carbon black/poly(butyl methacrylate)

Conductive composites from carbon black/poly(butyl methacrylate) (CB/PBMA) are synthesized through polymerization filling. The experimental results indicate that relatively low percolation threshold (similar to6wt%) is associated with the composites. When the composites are exposed to good solvent vapors of the matrix polymer, the electric resistance of the composites drastically increases by over 104 times. In the case of poor solvent vapor, however, the electrical response of,the composites is rather weak, demonstrating selective gas sensibility. In addition, environment temperature exerts, great influence on the responsivity of the composites against organic vapors. The higher the temperature, the faster and the stronger the electrical response. It was also found that the response of electric resistance of the composites against good solvent vapors is provided with sufficient reproducibility and stability. It can thus be concluded that the CB/PBMA composites can be used as promising gas sensing materials in practice.