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The effects of recycling of branched polypropylenes on their rheological properties and foamability are studied in this paper. The rheological properties and foamability of branched polypropylene are compared with those of the virgin sample. The main purpose of the study was to explore the possibility of using recycled materials to make the acceptable foam products. The recycled polypropylenes showed the lower melt strength due to the lowered molecular weight and disentanglement of molecules. However, the high-shear viscosities of the virgin and recycled resins exhibited almost the same values whereas the zero-shear rate viscosity was lower for recycled ones. The rheological behavior of the resins was correlated to the foaming behavior. It was observed that the contribution of the storage modulus (G’) was more pronounced than the loss modulus (G”). The foam morphology of recycled branched polypropylene and the virgin material was studied at various processing temperatures using a single-screw tandem foam extrusion system. The volume expansion ratio and cell population density results were correlated with the rheological data. Despite the noticeable drop in the melt strength, it was found that the foamability did not significantly deteriorate by recycling.

Cotton fabric has been made electro‐conductive by electroless deposition of silver from its salt solution. Preparation process involved radical graft polymerization of glycidyl methacrylate monomer on plain woven cotton fabric using 10 kGy dose of electron beam irradiation, and then hydrazination of the epoxy ring of the monomer to introduce reducing agents into the fibre chemical structure. These reducing agents are sites for metal particle deposition. The chemical modifications were characterized by infrared spectroscopic studies. From X‐ray diffraction pattern analysis, the average size of these deposited silver metallic particles is 41 nm. These are observed as heterogeneous deposition on the fibre surface in scanning electron images. From thermogravimetric analysis, around 7.5% of the metal plated fabric weight is silver. The deposited silver nanoparticles make a conductive pathway through contact network, and this network brings a drop in average value of surface resistivity of the cotton fabric from 109 Ω/sq to 3.63 Ω/sq for the metallised fabric. Such prepared electro‐conductive fabric showed very good wash durability of electrical conductivity up to 15 washing cycles when carried out as per ISO‐105‐C10:2006 (E) test no. A (1) standard, indicating firm adherence of silver nanoparticles to the fabric surface. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44576.