Thermal and dynamic mechanical analysis of polyethylene modified with crude palm oil.

This paper is focuses on the study of the thermal and dynamic mechanical properties of polyethylene (PE) modified with crude palm oil (CPO). PE of grades LLDPE and HDPE were used in this study. Various compositions of CPO and PE compounds were prepared in a twin-screw extruder. Films of 0.2 mm thickness were produced by using blown film technique. LLDPE and HDPE with CPO samples show only one melting temperature peak in DSC results, indicating the existence of one type of crystal species on all PE matrices. Dynamic mechanical analysis (DMA) shows the decrease of storage modulus was effect of plasticing of CPO. The shifting of b transition peak was observed on both polymers with the addition of CPO indicating the CPO has a lubricating effect on both polymers. � 2007 Elsevier Ltd. All rights reserved

Comparative study of polypropylene composites reinforced with oil palm empty fruit bunch fiber and oil palm derived cellulose

In recent years, the race for producing biodegradable products has increase tremendously. Different approaches have been attempted to use biomass as natural biopolymer for production of biodegradable plastics. In this work, cellulose was derived from oil palm empty fruit bunch fiber (EFBF) by standard ASTM D1104 method. The cellulose and EFB fibers were blended in different ratios up to 50-wt.% with polypropylene (PP) using Brabender twin-screw compounder. Effects of cellulose and EFB fibers on the mechanical properties of PP were investigated. Studies on the morphological properties and the influence of fiber loading on the properties of PP-cellulose and PP-EFBF composites were also conducted. The PP-cellulose composite gave better results in comparison with PP-EFBF composite. The changes in mechanical and morphological properties with different cellulose and fiber loading were discussed

Waste tire rubber in polymer blends: a review on the evolution, properties and future

This review addresses the progress in waste tire recycling with a particular attention to incorporation of waste tire rubber (WTR) into polymeric matrices. Methods of waste tire downsizing, importance of WTR characterization and current practice of WTR modification has been emphasized. Detailed discussion on influence of WTR size, loading, modification, compatibilization and crosslinking on the rheological, mechanical and thermal properties of rubber, thermoplastic and thermoplastic elastomer blends utilizing WTR has been reported. By far, thermoplastic elastomer blends; though still in its infancy; has shown the most promising properties balance which is capable of commercialization. Rubber/WTR blends also show ease of processing and acceptable properties. Thermoplastic/WTR blends suffers in term of toughness and elongation at break. However, the waste thermoplastic/WTR is a viable solution to address polymeric waste problem. Review also highlights the lack of studies concentrating on dynamic mechanical, aging, thermal and swelling properties of WTR polymeric blends

Thermal and dynamic mechanical behavior of cellulose- and Oil Palm Empty Fruit Bunch (OPEFB)-filled polypropylene biocomposites.

This paper presents a comparative study on the effect of cellulose and oil palm empty fruit bunch (OPEFB) on thermal degradation and dynamic mechanical properties of polypropylene (PP) biocomposite. Thermogravimetric analysis (TGA) of the biocomposite showed decrease in thermal stability and degradation temperature and increase in ash content. This was a result of lower thermal stability of the biofiller compared of that of the PP. However, an improvement was observed in the thermal properties of PP-cellulose biocomposite due to the dispersion and interfacial adhesion between the cellulose and PP. The glass transition temperatures (Tg) of the biocomposites were not significantly changed. The storage modulus (E′) of the biocomposites was found to be higher than that of pure PP, because incorporation of biofiller increased the stiffness of the biocomposites. The decline in E″ of the biocomposites at higher temperatures is associated with the increasing viscosity and chain mobility of matrix polymer

Improved crystallinity and dynamic mechanical properties of reclaimed waste tire rubber/EVA blends under the influence of electron beam irradiation

Dependence on automobiles has led to a huge amount of waste tires produced annually around the globe. In this study, the feasibility of recycling these waste tires by blending reclaimed waste tire rubber (RTR) with poly(ethylene-co-vinyl acetate) (EVA) and electron beam irradiation was studied. The RTR/EVA blends containing 100–0 wt% of RTR were prepared in the internal mixer followed by electron beam (EB) irradiation with doses ranging from 50 to 200 kGy. The processing torques, calorimetric and dynamic mechanical properties of the blends were studied. Blends were found to have lower processing torque indicating easier processability of RTR/EVA blends compared to EVA. RTR domains were found to be dispersed in EVA matrix, whereas, irradiation improved the dispersion of RTR into smaller domains in EVA matrix. Results showed the addition of EVA improves the efficiency of irradiation induced crosslink formation and dynamic mechanical properties of the blends at the expense of the calorimetric properties. Storage and loss modulus of 50 wt% RTR blend was higher than RTR and EVA, suggesting partial miscibility of the blend. Whereas, electron beam irradiation improved the calorimetric properties and dynamic mechanical properties of the blends through redistribution of RTR in smaller domain sizes within EVA

Effect of methyl methacrylate grafted kenaf on mechanical properties of polyvinyl chloride/ethylene vinyl acetate composites

In this work, the effect of grafted and ungrafted kenaf fiber on tensile, flexural, impact and hardness properties of polyvinyl chloride/ethylene vinyl acetate composites were studied. Grafted fibers were obtained from graft copolymerization reaction where methyl methacrylate was used as a monomer. The fiber loadings were varied from 0% to 30%. The addition of kenaf fiber had caused a decline in the impact and tensile strength of the PVC/EVA composite. Results revealed that the presence of PMMA on the surface of kenaf fiber has further enhanced the efficiency of stress transfer from the matrix to the fiber grafting thus improved the interfacial adhesion between the fiber and PVC/EVA matrix

Effect of mixing conditions on the tensile properties of ethylene vinyl acetate/waste tire dust (EVA/WTD) blend

Blends of Ethylene Vinyl Acetate/Waste Tire Dust (EVA/WTD) were prepared by using a Haake Rheomix at 100/0, 90/10, 80/20, 70/30, and 60/40 blend ratios. The effect of mixing temperature, blend ratio and blending time on the tensile properties of EVA/WTD blends were investigated. The mixing time was varied from 5 to 30 minutes, while the mixing temperature was varied from 120 to 160°C. The tensile properties of the blends found to show a gradual decrease with the addition of WTD. EVA/WTD blends prepared at 140°C mixing temperature and 10 min mixing time found to be suitable mixing parameters to obtain optimum blend properties. In general, declines in the EVA/WTD blends properties were also observed with increase in mixing time and temperature

Electron beam crosslinked natural rubber/multiwalled carbon nanotube nanocomposite

The physical properties of the rubber blends are influenced by vulcanization and filler distribution. Normally, rubbers are vulcanized by systems based on sulfur or peroxide with the most common filler carbon black. Radiation can also produce crosslink densities like those obtained by sulphur curing, but the net effects, are similar, though not identical. The type of crosslink formed in this method (–C–C–) give rise to better mechanical properties at higher temperature. This work reports on the investigations carried out on natural rubber (SMR) filled with the multiwall carbon nanotubes (MWCNTs). This system of SMR/MWCNTs was subjected to different radiation dosages and compared with nonradiated samples in order to determine the improvement in mechanical properties of the rubber system in the presence of MWCNTs and irradiation dosages. The amount of MWCNTs in this study was varied from 1 to 7 Phr and the irradiation doses were varied from 50 to 200 KGy. Mechanical properties, especially, tensile strength (TS), elongation at break had been studied as a function of irradiation dose and degree of loading with MWCNTs. Gel fraction indicated an increase in the degree of crosslink with the increase in the MWCT and radiation dosage. XRD was carried out to check the increase in the crytallinty of the nanocomposite system. The overall results obtained indicate significant improvement in the mechanical and thermal properties by radiation crosslinking in presence of MWCNTs. These results were further supported by TEM micrograph and nanoindentation

Performance of irradiated and crosslinked ethylene vinyl acetate/waste tire dust blend

The effect of irradiation on a 90/10 ethylene vinyl acetate/waste tire dust (EVA/WTD) blend was studied in the presence of 4 phr trimethylolpropane triacrylate (TMPTA) or tripropyleneglycol diacrylate (TPGDA). The blend was irradiated using a 3.0-MeV electron beam machine at 0, 50, 100, 150, and 200 kGy irradiation doses. The properties studied include gel content, tensile properties, hardness, morphology, and dynamic mechanical properties. The result revealed that the increment in irradiation doses will increase the percentage of gel content. The gel content further increased with the introduction of TMPTA and TPGDA. This is attributed to the increase in crosslink density. Tensile properties of EVA/WTD blend increase with the introduction of irradiation except for elongation at break. The tensile-fractured surface of EVA/WTD blends showed ductile type of failure upon irradiation of the blends in the presence of crosslinking agent. One glass transition temperature obtained from dynamic mechanical analysis for 90/10 EVA/WTD blend after irradiation indicates that compatibility between EVA and WTD phases increased