Forschung Zur Rubrik

Premium
Kurvendiagramm mit bunten Linien und Beschriftung.
Nonlinear behavior functionalized SBR Silica Compound

Does nonlinear Viscoelasticity ­inherently exist in Rubber?

This study investigates the transition from linear to non-linear viscoelastic behavior in polymers and rubber compounds under cyclic sinusoidal shear deformation. The stress response is analyzed through Fourier series decomposition, enabling the definition of the generalized elastic modulus, G0' (γ0) and viscous modulus. These parameters are critical for characterizing the complex viscoelastic properties. It is shown that G0' (γ0) comprises two distinct contributions: the first harmonic, corresponding to the linear elastic response, and the non-linear modulus GN′L (γ0 ) which arises from all higher harmonic components. The study further examines the effect of carbon black fillers on nonlinear viscoelasticity, revealing significant nonlinearity induced by the fillers.

Premium
Liniendiagramm mit Beschriftung in schwarz und rot.
Effect of Silica on Post-Crosslinking

Investigation of the ­Post- Hardening Effect in a Silica filled NR-Compound

Storage hardening is an effect that commonly occurs in unvulcanized natural rubber (NR) compounds. In this study, the increase in hardness during storage of a vulcanized NR compound filled with silica was investigated. An increase in hardness during storage at room temperature and at 60 °C was observed. It was expected that this post-hardening effect was caused by the increasing formation of mono- and disulfidic bonds created out of broken polysulfidic bonds. However, Temperature Scanning Stress Relaxation (TSSR) and the thiol-amine method showed an unexpected increase in polysulfidic bonds for the stored compounds. This formation of additional polysulfidic bonds is likely enhanced by the residual MBT formed during the vulcanization process accelerated with CBS.

Roh- & Zusatzstoffe Zur Rubrik

Verarbeitung Zur Rubrik

Werkzeug & Formen Zur Rubrik

Qualitätssicherung Zur Rubrik

Aus unserem Netzwerk