A new method for measuring the degree of crosslinking in elastomers

Abstract

A rapid method for determining the degree of crosslinking in elastomers is described which involves measuring equilibrium compression modulus at very small deformations on solvent‐swollen samples. The elastomer used was a polyether urethane vulcanized by an accelerated sulfur recipe. The degree of crosslinking as measured by the compression method agreed with that measured by the extension method within 1–3%. Both methods agreed reasonably well with the theoretical values calculated from the sulfur level, polymer molecular weight, and crosslink structure.

Interrelationship between ultimate mechanical properties of variously structured polyurethanes and poly(urethane urea)s and stretching rate thereof

“…The effective density of spatial network conditioned by hard segments' domains and by chemical cross-linkage N dx was determined using the Cluff-Gladding-Pariser method [27] on equilibrium samples swollen in toluene which did not affect the hard domains [14,15] and on samples swollen in TBP. Equilibrium swelling in TBP completely destroys the domain structure of polymers [15].…”

Physically crosslinked alginate/N,O-carboxymethyl chitosan hydrogels with calcium for oral delivery of protein drugs

“…The crosslinking densities of calcium-alginate-NOCC beads were evaluated by determining the modulus of elasticity in compression as described elsewhere [21,22].…”

Influence of Gluten and Gum Additives and Cryogenic Treatment on Some Properties and Morphology of Wheat Starch Complex Gels

“…The deformation was measured with 0.001 cm accuracy, which corresponds to relative deformation of 0.05% for the sample of 2 cm height. Similarly to the Cluff's method [21], the modulus of elasticity was calculated by the slope ratio of the stress dependence on deformation. The modulus of elasticity was measured for five parallel samples, and the results were averaged.…”