Evaluation of the suitability of different methods for determination of the crosslink density in highly filled EPDM compounds

Abstract The crosslink density of elastomers is the essential property that determines many other but especially mechanical product properties. Different raw materials, recycled and bio-based influence vulcanization may change when they are used as a substitute to conventional materials. Aim this study develop procedure allows reliable determination in highly filled EPDM compounds basis for future investigations focussed on substitution with sustainable materials compound. Unfortunately, experiences rubber like tire treads cannot be directly applied here because use filler types amounts well differences polymer regard active sites (available double bonds). Equilibrium swelling, Flory-stress-strain-measurements, freezing point depression temperature-scanning-stress-relaxation model compound high softener amount typically sealings. For sensitivity investigation agent sulfur was varied. Furthermore, different accelerators investigated. All methods able determine standard deviations due measurement errors. Partially, can optimized case. Based results combination Flory-stress-strain-measurements chosen future.