A theoretical model for the prediction of tensile strengths of particulatefilled polymers is proposed. According to this model each particle is divided into an infinite number of coaxial cylinders and by applying Cox's theory the mean stress developed in each section of the particle may be calculated. Further a modified rule of mixtures was applied where the degree of adhesion between matrix material and filler particles as well as the degradation of the mechanical behaviour of the matrix due to the existence of the particles is taken into account. Therefore, when tensile strengths of polymer and particles are known, tensile strength of the filled polymer corresponding to specific values of degree of adhesion as well as of the matrix degradation can be estimated by the model. Finally, the model was successfully applied to a series of published data.

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SynopsisGel permeation chromatography (GPC) calibration curves log hydrodynamic volume versus elution volumes were obtained from a series of single and mixed eluents for polystyrene on inorganic carriers. The observed calibration shifts were interpreted as a result of adsorption and partition effects on elution volume V,. Secondary contributions to the separation mechanism can be qualitatively described by means of thermodynamic relations from liquid adsorption (LSC) and liquid partition (LLC) chromatography using the solubility parameters of the eluents. The universal calibration procedure based on the hydrodynamic volume of the coils is directly applicable only for systems in which adsorption and partition is approximately the same.

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