Glass transition temperatures of poly(vinyl chloride) and polyacrylate materials and calcium ion-selective electrode properties

Abstract

The glass transition temperatures of eight poly(vinyl chloride)(PVC) samples of different relative molecular masses in addition to poly(methyl acrylate), poly(methyl methacrylate) and poly(2-methylpropyl methacrylate) were determined, in some instances as electrode master membranes with incorporated sensor and solvent mediators. They were also investigated as support matrices for calcium ion-selective electrodes (ISEs) based on calcium bis{di[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphate} with dioctylphenyl phosphonate or other liquids as solvent mediator. No important difference in terms of response times, selectivity coefficients, Nernstian slopes, membrane resistances or pH-e.m.f. profiles were exhibited by the eight PVC-based electrodes. Functional calcium electrodes were also fabricated with a poly(2-methylpropyl methacrylate) matrix but not with corresponding poly(butyl methacrylate), poly(methyl methacrylate) or poly(methyl acrylate) matrices.