Navier's slip Coefficient Determination of Silicone Rubber Compound by means of High-Pressure Capillary Rheometer

摘要

The unique properties of silicone rubber, such as high heat and chemical resistance are the main reasons for its growing importance in the industry [1]. Unfortunately, silicone rubber shows wall slip even at low shear rates [2]. The wall slip phenomenon influences rheological measurements and leads to difficult process descriptions. This phenomenon might be predicted by a rheological model like the one used by Lawal et al. [3]. For calulating the relationship between pressure differential and volume flow rate using this model, Navier's slip coefficient is a key parameter. In order to determine this coefficient, investigations are carried out using a high-pressure capillary rheometer (HCR). It is found that when using the Mooney-Geiger method, the slip coefficient depends on both shear rate and shear stress.