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In this work, we report a melt blend of poly(lactic acid)(PLA)/epoxidized natural rubber (ENR) with liquid natural rubber (LNR). The LNR was synthesized by a photochemical degradation technique and used as a compatibilizer in the PLA/rubber binary blending systems. The PLA/ENR/LNR blends were melt-blended in a Haake internal mixer at 180°C and mixing speed of 50 r. min−1 for 15 min. It was found that the addition of LNR compatibilizer has improved the tensile strength and elongation at break for the compositions of the 40PLA/55ENR/5LNR blend system when compared with a noncompatibilized system (40PLA/55ENR/5NR). The elongation at break for the blend with 5% LNR compatibilizer showed a twofold increment compared with the blend without LNR. The increase in tensile strength and elongation at break were associated with the ability of LNR to promote the uniform dispersion between the natural rubber (NR) and PLA phases as observed in the scanning electron microscopic analysis. Moreover, the differential scanning calorimetric results indicated that the 40PLA/55ENR/5LNR showed the highest degree of crystallinity and thus contributed to improve their mechanical properties. Thermogravimetric analysis showed that two degradation transitions for both compatibilized and noncompatibilized blend systems due to higher degradation temperatures of ENR50 and NR parts. Fourier transform infrared spectroscopic analysis revealed that the PLA/ENR/NR and PLA/ENR/LNR blends were not miscible. [ABSTRACT FROM PUBLISHER]

Phenol formaldehyde (PF) resin prepared from phenol-liquefied empty fruit bunch (EFB) fibres was blended with polypropylene (PP) using a co-rotating twin-screw extruder. The effects of the PF content (10, 20, 30 and 40 wt.%) blended with PP on the properties of the PP/PF board were investigated. SEM images depicted the formation of spherical protuberances and voids in the PP/PF board with the increasing PF content. The size of the protuberances was also increased with the PF content. The formation of void could be due to the release of water, ammonia and formaldehyde during the blending and hot-press processes. The density, moisture content and maximum water absorption of the PP/PF board increased with the increase of PF content. The TG curves of the PP/PF boards revealed that the PF and PP in the PP/PF board decomposed at different temperature ranges, i.e., 200-420 and 425-480 °C, respectively. The addition of PF to PP reduced the activation energy of the first stage thermal decomposition of the PP/PF boards. The addition of 10 wt.% PF was the optimum content to produce PP/PF board with optimum mechanical properties. [ABSTRACT FROM AUTHOR]

This study investigated the mechanical properties of thermoplastic natural rubber (TPNR) nanocomposites reinforced by multi-walled carbon nanotubes (MWNTs). The TPNR nanocomposites were prepared using melt blending method from polypropylene, natural rubber, and liquid natural rubber as a compatibilizer, respectively, with 1—7 wt% of MWNTs. The tensile strength and Young’s modulus increased by almost 39% and 30%, respectively, at 3 wt% of MWNTs. The elongation at break decreased with increase in the percentage of MWNTs. The maximum impact strength was recorded at 5 wt% of MWNTs which was increased by 74% as compared with a pristine TPNR sample. The effect of MWNTs was also confirmed by DMA; it showed that the storage modulus E′, loss modulus E′′, and glass transition temperature (Tg) also increased for all MWNT reinforced samples. SEM micrographs confirm the effect of good dispersion of MWNTs and their interfacial bonding in TPNR. [ABSTRACT FROM PUBLISHER]

This article studies the thermal properties of a multi-walled carbon nanotube (MWNT)-reinforced thermoplastic natural rubber (TPNR) nanocomposite. The nanocomposite was prepared using a melt blending method. Various percentages (1, 3, 5, and 7 wt%) of MWNTs were added into TPNR to improve its thermal properties. The laser flash technique was also employed to determine the thermal conductivity, thermal diffusivity, and specific heat capacity of the nanocomposite. The DMA result showed that the glass transition temperature (Tg) increased with the increase in MWNT content. TEM micrographs also demonstrated that a good dispersion of MWNTs was achieved in the TPNR environment. [ABSTRACT FROM AUTHOR]