Spun thin films of poly(methyl methacrylate) polymer for benzene sensing

Thin films of poly(methyl methacrylate) (PMMA) were deposited on suitably prepared substrates by spinning the spreading solution in chloroform at 3000 rpm for atomic force microscopy and surface plasmon resonance studies. Four different types of PMMA were used within a range of molecular weight between 540 and 760 kg mol(-1). The film surface was found to be uniform. Values of refractive index for PMMA film were found to exist in the range of 1.50 +/- 0.04 to 1.53 +/- 0.02. All films exhibited fast response to the exposure of benzene vapour but the sensitivity of detection depended upon the molecular weight.