In the present study, waste jute fibers generated in textile industries, were wet pulverized to the scale of nanofibers of 50 nm diameter using high energy planetary ball milling for 3 h. The presence of water during wet pulverization found to reduce the rising temperature of mill, which prevented sticking of nanofibers on the mill wall and resulted in unimodal size distribution. In the subsequent stage, 1, 5, and 10 wt% of jute nanofibers were incorporated in poly(lactic acid) (PLA) matrix to prepare nanocomposite films by solvent casting. The reinforcement of nanofibers was investigated from the improvements in mechanical properties based on tensile tests, dynamic mechanical analysis, and differential scanning calorimetry. The maximum improvement was observed in case of 5 wt% nanocomposite film where initial modulus and tensile strength increased by 217.30% and 170.59%, respectively as compared to neat PLA film. These improvements are attributed to the increased interaction between nanofibers and matrix as well as to the increased crystallinity of PLA in composites. The improvements in load bearing capacity of nanocomposite films were significant at 60°C than 35°C, which showed ability of jute nanofibers to improve the softening temperature of PLA matrix. In the end, experimental results of Young's modulus were compared with predicted modulus of mechanical models. A good level of agreement was observed up to 5 wt% loading of jute nanofibers. POLYM. COMPOS., 34:2133–2141, 2013. © 2013 Society of Plastics Engineers

In this work, long basalt fiber reinforced composites were investigated and compared with short basalt fiber reinforced compounds. The results show that long fiber reinforced thermoplastic composites are particularly advantageous in the respects of dynamic mechanical properties and injection molding shrinkage. The fiber orientation in long basalt fiber reinforced products fundamentally differs from short basalt fiber reinforced ones. This results in more isotropic molding shrinkage in case of long basalt fiber reinforced composites. The main advantage of the used long fiber thermoplastic technology is that the special long fiber reinforced pellet can be processed by most conventional injection molding machines. During extrusion compounding the fibers in the compound containing 30 wt% fibers are fragmented to an average length of 0.48 mm (typical of short fiber reinforced thermoplastic compounds), this length decreases further during injection molding to 0.20 mm. Contrarily using long fiber reinforced pellets and cautious injection molding parameters, an average fiber length of 1.8 mm can be achieved with a conventional injection molding machine, which increased the average length/diameter ratio from 14 to 130. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers

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Polypyrrole (PPy), one of the most extensively investigated conducting polymers, has attracted a great deal of interest because of its good electrical conductivity, environmental stability, and easy synthesis. PPy films were produced by polymerization of pyrrole and tosylate (TsO−) as dopants in the presence of oxidant FeCl3 and polyethylene glycol (Mw 8000) at −5°C for 48 h. High energy milling was carried out at 850 rpm in the dry media with the balls of 10 mm. Particles were then characterized by Scanning Electron Microscope and Dynamic Light Scattering techniques for size distribution, and it was found that the size of PPy particles is a decreasing function of time of milling. Electrical conductivity was measured by preparing a homogenous aqueous dispersion of PPy particles and found as exponential decreasing function of time of milling. The changes occurred in PPy after milling was analyzed by Differential Scanning Calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR).

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