Organically Modified Layered Silicate Effects on PS/PMMA Blends: Morphological AndRheological Behavior

摘要

The influence of an organically modified layered silicate on the compatibility and dynamics of animmiscible blend of atactic polystyrene (PS) and poly(methyl methacrylate) (PMMA) is studied. Bulksamples of equal volume fraction blends of PS and PMMA, examined here, form large phase separateddiscrete phases of PMMA in a continuous PS matrix. The addition of the organoclay nanoparticles at aconcentration of 0.6 wt % results in a significant alteration of the morphology with co-continuousdomains of PS and PMMA including discrete and small domains of the other component dispersed inthese continuous domains. This drastic change in morphology is reflected in the melt-state rheologicalbehavior of the nanocomposites when compared to the blend. The nanaocomposite with 0.6 wt% layeredsilicate exhibits longer relaxation time and higher modulus at low-frequencies. The Palierne dynamicmodel is used to quantify the observed relationship between the melt-state rheological behavior and theobserved morphology for the blend nanocomposite.