AbstractThe Young's moduli of samples of poly(vinyl chloride) containing either no plasticizer or 5 pph of dioctyl sebacate were drawn uniaxially at 80°C to draw ratios, λ, in the range 1–3.3. The moduli, determined by a three‐point bending method were found to increase monotonically with λ to a value of 6.3 GPa for the nonplasticized samples and to reach a maximum value of about 4.5 GPa for the plasticized samples above λ = 2.3, which showed voiding. The lower moduli of the plasticized samples for a given degree of orientation, as assessed from birefringence measurements, can be attributed to the diluent effect of the plasticizer on the load‐bearing chains. The Raman measurements suggest that the crystallites probably orient rather like rigid rods in an affinely deforming matrix, with some r
展开▼
