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This paper describes a technique, which enable one to overcome several difficulties encountered in a conventional deformed drop retraction method. The technique consists of forming deformed drops by the disintegration of a polymer thread and measuring the shape evolution of the drop. It is found that the technique enables one to overcome the difficulties encountered in the conventional deformed drop retraction method. By the optical microscope observation, it was confirmed that the disintegrated drop maintains the axisymmetrical ellipsoidal shape during the retraction process and was parallel to the observation plane. The interfacial tension obtained by the technique was found to be lower than the data from the breaking thread method. This variation was discussed in terms of the interfacial contact time.

The effect of polar comonomers introduced into polystyrene (PS) chains on the melt intercalation into organosilicate is investigated in terms of shear and annealing time. In the case, where the interaction between polymers and silicate layers is relatively weak, e.g. PS/organosilicate hybrids, it is difficult for the polymer chains to diffuse into interlayers of organosilicate and the hybrids are unstable under shear. For hybrids in which the interaction is enhanced by incorporating polar comonomers, e.g. acrylonitrile (AN) and methylvinyl oxzoline (OZ), their structures are stable even after a long mixing time. However, they do not show an exfoliated structure under the mixing conditions used in this study. The interaction between the comonomer and the silicate surface is investigated indirectly via both X-ray diffractional and FTIR spectral analyses. It is concluded that the structural stability of polymer/organosilicate hybrids is very dependent on the relative magnitude of the interactions between polymers, organic modifiers, and silicate layers.

Ternary blends of polysulfone (PSF)/polycarbonate (PC)/Impact modifiers (IM) were prepared to improve the mechanical properties of PSF/PC binary blends. Two different core–shell impact modifiers, methyl methacrylate–butadiene–ethylacrylate (MBE) and acrylonitrile–butadiene–styrene (ABS) terpolymers, were used. Morphology of the blends was very dependent on thc matrix type but independent of the IM type. For PSF matrix PC tends to encapsulate the IM. Whereas, for PC matrix, the IM tends to locate in PC matrix and thus two distinct phases of PSF and IM are observed. The encapsulation of PC onto the IM in PSF matrix was verified from the model blends of PSF/PC/SAN24 and PSF/PC/PMMA, where SAN24 and PMMA are corresponding to the shell of the IM, respectively. Impact strengths of the blends with the IM were slightly increased compared to PSF/PC binary blends, but not significantly. This may be the result of poor PSF/PC interfaces, which are valid from their immiscibility.

The miscibility of poly(vinylidene fluoride) (PVDF) and poly(styrene-co-methyl methacrylate) (SMMA) blends was examined as a function of copolymer composition. PVDF was miscible with SMMA copolymers having an styrene content less than 13 vol%. The segmental interaction parameters were determined by combining the equilibrium melting point depression of PVDF and the binary interaction model. According to the binary interaction model, the maximum styrene content in SMMA for the blend to be miscible was predicted as 18.5 vol% which agrees well with an experimental result.