Modeling of elastic-strength properties of elastomers
Model "structure-property", which takes into account the structural heterogeneity of polymer compositions has been developed. Experimental compositions based on styrene-butadiene rubber SCS 30ARK and crosslinked, high viscosity polymer (high-molecular filler - VMN) in different proportions, as well as softeners (industrial oil I-12A, oil PN-6, low-molecular polybutadiene PBN) were investigated. Samples that differ significantly in viscosity were obtained. The rubber blends and vulcanizates, based on the experimental of polymer compositions, were prepared. Physico-mechanical properties - tensile strength, elongation at break, Shore A. A hardness were determined. For describe the physical and mechanical properties of polymers logarithmic additivity rule was used. The properties of the polymer composition (PС) were determined by a single dominant component (resin composition consisting of a high rubber and a filler) and further components (softeners). Identification algorithm consists of four steps. The implementation of this algorithm is carried out using experimental design techniques. Estimation of the unknown parameters in the equation was carried out using the method of least squares. Quality evaluation of the model was conducted with the criteria Fisher, turning points, the Durbin-Watson, R / S-criterion. It is found that the model adequately describes the change of physico-mechanical properties depending on the composition of polymer compositions. 3d graphics of the physical-mechanical properties of the polymer compositions were built. This allowed us to estimate the contribution of the dominant component and optional components (including combinations thereof) to change the parameters. It has been established that the introduction of rubber in total more than 50% of the components (BMH and softeners) reduced conventional tensile strength and dramatically increases the relative error of model calculations. (BMH and softeners) reduced conventional tensile strength and dramatically increases the relative error of model calculations.