The present work accounts new approach for processing of PP nanocomposites containing 5 phr pristine Na þ montmorillonite clay with better clay dispersion by a single-step process along with improved processability using hyperbranched polyester (HBPE). A series of PP/MMT nanocomposites with different HBPE contents were fabricated by direct melt compounding on a Brabender torque rheometer where all components of the blends were fed simultaneously for mixing. The efficiency of this approach was evaluated against PP/MMT nanocomposites prepared with polypropylene graft-maleic anhydride (PP-g-MA) compatibilizer. The overall results revealed that systems with HBPE showed better balance of rheology and mechanical properties than nanocomposites with PP-g-MA. INTRODUCTIONIn the field of nanocomposites, polymer=layered-silicate nanocomposites have attracted considerable attention over the past decade as they offer remarkable enhancements of mechanical, thermal and barrier properties compared to pure polymers or conventionally filled composites [1][2][3][4] . However the complete dispersion or exfoliation of the clay nanolayers into the polymer system is necessary to get composites with improved mechanical performance but it proved to be a challenging job due to difference in polarity of polymer matrix and nanoparticles [5] .Significant research done by Toyota research group in the preparation of nylon-6=nano-clay composites has opened rebellion potential in the development of new nanostructured materials, where the property enhancements originate from the result of homogeneous dispersion of the silicate layers which was made possible due to better

In the present investigation, nanocomposites of polypropylene (PP)‐montmorillonite (MMT) clay were prepared by a single‐step compounding method to study the influence of hyperbranched polyester (HBPE) on rheological and mechanical properties of PP composites in the presence of a compatibilizer. In service of this objective, polyvinylchloride‐grafted‐maleic anhydride (PP‐g‐MA) was used as a compatibilizer for hydrophobic PP and hydrophilic clay. Rheological property in terms of melt viscosity was examined by a Brabender torque rheometer. The composite's morphology was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), whereas the dispersion state of nanoparticles in the PP matrix was studied by X‐ray diffraction (XRD). The thermal behavior of nanocomposites was examined by differential scanning calorimetry (DSC). The analysis of results confirmed that the interactions among both additives significantly influenced the morphology, rheology, and thermomechanical properties of the nanocomposites. J. VINYL ADDIT. TECHNOL., 22:72–79, 2016. © 2014 Society of Plastics Engineers

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This work focused on two difficulties associated with preparation of polypropylene/wood flour (PP/WF) composites, viz. the compatibility of PP with WF and processing of the composites with high melt viscosity. Maleic anhydride-grafted polypropylene (MAPP) was used in the preparation of PP composites to provide the compatibility between polymer and filler. Hyperbranched polyester (HBPE) was incorporated to check feasibility of it as a processing aid in the same. The PP/WF composites were formulated by melt compounding on a Brabender Plastograph EC. Blending effect of compatibilizer and processing aid HBPE on PP/WF biocomposites have been carried out on the basis of torque analysis, mechanical properties, morphology, and thermal stability. The investigation showed that HBPE improves the processibility of PP/ WF composites than MAPP with respective to torque value. The mechanical and thermal properties slightly vary with change in relative proportion of MAPP and HBPE.

The use of ionic liquids as additives and an economic and environmentally benign alternative to conventional inorganic and organic additives in poly(vinyl chloride) (PVC) formulation is investigated by using thermogravimetric analysis. The present study deals with an elegant exploration of the resulting thermal profiles to disclose the pattern of thermal degradation for N-butylpyridinium hexafluorophosphate and PVC formulation as well. Furthermore, non-isothermal kinetic investigations providing sound information about kinetic parameters, such as activation energy and frequency factor by using the Coats-Redfern equation in the temperature range of 593-663 K for N-butylpyridinium hexafluorophosphate and 423-473 K for the resulting PVC formulation were performed.