Gelation and Fusion Characteristics of PVC Resins in Plastisol by Determination of Their Viscoelasticity
A method of characterizing gelation and fusion behavior by viscoelastic measurements has been developed previously1. The present work is an application of this method for finger-printing the gelation and fusion profiles of commercial dispersion resins. The Rheometrics Mechanical Spectrometer was used in the dynamic oscillatory mode at 1 Hz with a programmed increase of temperature. The elastic modulus, G′, loss modulus, G″ and the complex viscosity |η*| were recorded as functions of temperature. Two temperature profiles were used: one was 20°C/min. to simulate a process, i.e., a heating rate in an oven, and the other was 5°C/min., a slower heating for a better characterization of gelation behavior.