Phase Structure of PVC/MBS Blends by Small Angle X-ray Scattering

The phase structure of blends consisting of polyvinyl chloride (PVC) and methyl methacrylate—butadiene—styrene graft copolymer (MBS) are examined by small-angle-X-ray scattering (SAXS). The interface layer thickness (σ), correlation distance (ac), and interface layer specific surface area (Ssp) are calculated using Debye—Bueche's statistical theory. The results show that the grafted sequence of styrene or methyl methacrylate to butadiene—styrene copolymer have significant influence on the values of σ, ac, and Ssp. The σ-value of PVC/MBS in which styrene is first grafted in MBS is about 5 nm larger than that of methyl methacrylate (MMA) that is first grafted in MBS.