Abstract: In this paper, PNBR, Elvaloy741, and MBS were introduced into unplasticized PVC. The effect of contents of the modifiers on transmittance, haze, mechanical property, lowtemperature performance, hardness, and micromorphology were studied. It showed that the transparency of PVC/MBS and PVC/Elvaloy741 were fine. With the addition of the modifiers, the tensile strength of the blends decreased, the elongation at break increased, the lowtemperature performance improved, and the hardness were changed a little. The fracture of the sample showed a clear ductile behavior.

Key words: powdered butadiene-acrylonitrile rubber, ethylene-vinyl acetate-carbon monoxide terpolymer, methyl methacrylate-butadiene-styrene terpolymer, unplasticized poly(vinyl chloride), modification