Abstract
An apparatus and method are described for evaluating state of cure, optimum cure time, rate of cure, induction time for cure, scorch time, induction time for reversion, reversion rate and degree of reversion of elastomeric compounds. Coincident with these determinations vulcanizate specimens are prepared on which more conventional physical test data may be obtained; e.g., compression modulus, compression set, hardness, specific gravity, tensile modulus and elongation. In essence, the method described provides a progressive measure of modulus change during cure or reversion through the change in deformation of a periodically loaded plunger, one end of which is embedded into the specimen. Typical results are given which show application of the apparatus to screening tests, millroom control, reversion studies and to compounds which are too stiff for conventional test methods. Demonstrated advantages for the apparatus include time saving, stock saving and better cure information on a wider range of polymeric compounds than is obtainable from tensile test methods. In a laboratory where a large selection of test instruments is not feasible, the versatility of the apparatus described should prove very advantageous.