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This work demonstrates the significant interphase region of polyimide/titanium dioxide nanofiber nanocomposite. Interphase characteristics of nanocomposites were calculated using Interphase Power Model. It revealed that the interphase volume fraction and interphase dielectric constant were proportionately increased with filler loading at least up to 20%. The increasing trend of interphase dielectric constant signifies a loosely bounded polymeric chain onto the filler surfaces giving the interphase volume constant k as 2.05. However, the ratio of interphase volume to that of the filler volume progressively decreased which was attributed to the effect of agglomeration of filler and percolation of overlapping interphase region to yield an average interphase thickness of 81 ± 10 nm. By designing the complex function of interfacial interaction through the surface activity between the filler and matrix, the interphase region can be appropriately monitored in understanding its effects on glass transition and dielectric constant of the nanocomposites. [ABSTRACT FROM AUTHOR]

In this work, the feasibility of converting dead leaf biomass into green activated carbon for use as a reinforcement filler in natural rubber composites was assessed. The dead leaf activated carbon (DLAC) was prepared by pyrolysis at 550, 700, 900, and 1000 °C at a heating rate of 10 °C min−1 under nitrogen gas flow of 100 cm3 min−1 and was activated by CO 2 gas at the same flow rate when the pyrolysis temperature was reached. The properties of DLACs were characterized by particle size analysis, density, scanning electron microscopy, elemental energy-dispersive X-ray spectroscopy and Raman spectroscopy. The results revealed that the DLAC obtained by pyrolysis at 1000 °C had a small particle size of 28.86 μm; a highly porous structure; high carbon purity, at 82.58%; and a low density, at 1.588 g cm−3. The effect of different DLAC contents (5, 10, and 15 phr) on the curing properties and the physical and mechanical performance of the rubber composites was investigated and compared with rubber composites containing carbon black (CB). The results showed that the addition of DLAC increased the maximum torque and reduced the scorch and cure times. The tensile strength for rubber composites containing 15 phr of DLAC increased by 8%, the M100 and M300 improved 40%, and the elongation at break and crosslink density decreased by approximately 5% and 24%, respectively. The studied DLAC is a promising, cost-effective alternative to commercial carbon black for improving the performance of rubber composites. Image 1 • From dead leaf biomass to Dead leaf activated carbon (DLAC) by pyrolysis. • Potential use of DLAC as reinforcement filler in natural rubber. • DLAC filled rubber give similar mechanical properties to carbon black filled rubber. • DLAC is a promising cost effective to commercial carbon black in rubber composites. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the physical and mechanical performance of poly(lactic acid) (PLA), acrylonitrile butadiene styrene (ABS), and nylon 6 fabricated using fused deposition modeling (FDM) and conventional injection molding. It is found that different processing methods did not affect the viscosity of the samples, and the percentage difference for the density measurement is less than 4%. Water absorption of FDM samples is approximately 108% higher compared to those fabricated using the injection molding. The results also revealed that the FDM method did not strongly affect the degree of crystallinity of ABS, but it increased the degree of crystallinity of PLA and nylon 6. The tensile strength, Young's modulus, elongation at break, and impact strength of FDM samples were approximately 48%, 50%, 48%, and 78%, lower compared with the injection molded samples. The results presented can provide a guide to manufacturing the final products using FDM with the desired performance. Image 1 [ABSTRACT FROM AUTHOR]