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In spite of the reported temperature dependent tunability in wettability of poly(N-isopropylacrylamide) (PNIPAAm) surfaces for below and above lower critical solution temperature (32 °C), the transport of water droplets is inhibited by the large contact angle hysteresis. Herein, for the first time, we report on-demand, fast, and reconfigurable droplet manipulation over a PNIPAAm grafted structured polymer surface using temperature-induced wettability gradient. Our study reveals that the PNIPAAm grafted on intrinsically superhydrophobic surfaces exhibit hydrophilic nature with high contact angle hysteresis below 30 °C and superhydrophobic nature with ultralow contact angle hysteresis above 36 °C. The transition region between 30 and 36 °C is characterized by a large change in water contact angle (∼100°) with a concomitant change in contact angle hysteresis. By utilizing this "transport zone" wherein driving forces overcome the frictional forces, we demonstrate macroscopic transport of water drops with a maximum transport velocity of approximately 40 cm/s. The theoretical calculations on the force measurements concur with dominating behavior of driving forces across the transport zone. The tunability in transport velocity by varying the temperature gradient along the surface or the inclination angle of the surface (maximum angle of 15° with a reduced velocity 0.4 mm/s) is also elucidated. In addition, as a practical application, coalescence of water droplets is demonstrated by using the temperature controlled wettability gradient. The presented results are expected to provide new insights on the design and fabrication of smart multifunctional surfaces for applications such as biochemical analysis, self-cleaning, and microfluidics.

The present work involves the synthesis of a petroleum-based fuel by the catalytic pyrolysis of waste plastics. Catalytic pyrolysis involves the degradation of the polymeric materials by heating them in the absence of oxygen and in the presence of a catalyst. In the present study different oil samples are produced using different catalysts under different reaction conditions from waste plastics. The synthesized oil samples are subjected to a parametric study based on the oil yield, selectivity of the oil, fuel properties, and reaction temperature. Depending on the results from the above study, an optimization of the catalyst and reaction conditions was done. Gas chromatography-mass spectrometry of the selected optimized sample was done to find out its chemical composition. Finally, performance analysis of the selected oil sample was carried out on a compression ignition (CI) engine. Polythene bags are selected as the source of waste plastics. The catalysts used for the study include silica, alumina, Y zeolite, barium carbonate, zeolite, and their combinations. The pyrolysis reaction was carried at polymer to catalyst ratio of 10 : 1. The reaction temperature ranges between 400 ∘ C and 550 ∘ C. The inert atmosphere for the pyrolysis was provided by using nitrogen as a carrier gas.

1603

Rubber seed oil (RSO) and epoxidised rubber seed oil (ERSO) were used as secondary plasticiser cum heat stabiliser in polyvinyl chloride (PVC). High temperature mixing studies, dynamic mechanical analysis, hot air aging tests and colour stability tests indicated that ERSO could be used as a less volatile secondary plasticiser and heat stabiliser for PVC in combination with dioctyl phthalate (DOP). The tensile properties of the compound containing 50 : 10 DOP/ ERSO were found to be comparable to that containing 60 parts of DOP per 100 parts PVC.

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In this study, we report the synergistic role of (3-aminopropyl)triethoxysilane (APTES) functionalization of zinc oxide (ZnO) nanoparticles and low-temperature phase-inversion for boosting the polar β-phase of the poly(vinylidene fluoride) (PVDF) nanocomposite. The electroactive crystal phase was investigated with Fourier transform infrared, wide-angle X-ray diffraction, differential scanning calorimetry, dielectric spectroscopy, and dynamic contact mode electrostatic force microscopy. Our results confirm an enhanced polar β-phase and crystallinity, which inherently boosted the overall dielectric, ferroelectric, and piezoelectric properties of the PVDF/ZnO-APTES nanocomposite. The energy-harvesting potential of the nanocomposite was investigated by fabricating a piezoelectric device. The fabricated device with a high electroactive phase (PDVF/ZnO-APTES) exhibited a voltage of 125 V and an instantaneous output power density of ∼83 mW/cm 3 . The fabricated device can glow 8 lightemitting diodes (LEDs), blink 50 LEDs and could be a potential candidate for energy-scavenging applications.