Aznizam Abu Bakar

Effect of Oil Palm Empty Fruit Bunch and Acrylic Impact Modifier on Mechanical Properties and Processability of Unplasticized Poly(Vinyl Chloride) Composites

Abstract Interest in the use of natural fibers as fillers has grown over the past few years due to the advantages it offers. The use of oil palm empty fruit bunch (EFB) as a filler in the unplasticized poly(vinyl chloride) (PVC-U) is a new attraction in polymer composite technology. The objectives of this study are to investigate the effects of EFB fillers on processability and mechanical properties of unmodified and acrylic-impact modified PVC-U. To produce the compound, the PVC resin and the additives were first dry blended using a laboratory blender before being milled into sheets using two-roll mill. Test specimens were prepared using a hot press, after which impact and flexural properties were determined. The processability studies of the dry blend were carried out by using a Brabender Torque Rheometer model PL2200. The results showed that the incorporation of EFB filler into unmodified PVC-U decreased the fusion time, but increased the fusion time of acrylic-impact modified PVC-U. The end torque decreased upon the addition of EFB filler for both samples. The addition of 9 phr of acrylic impact modifier into the unfilled and EFB-filled PVC-U compound decreased the fusion time. The flexural modulus showed improvement upon addition of EFB filler, with a sacrifice in impact and flexural strength. The overall results show that the incorporation of EFB filler modified the processability and mechanical properties of both the unmodified and acrylic-impact modified samples.

The Effect of Oil Extraction of the Oil Palm Empty Fruit Bunch on the Processability, Impact, and Flexural Properties of PVC-U Composites

The use of oil palm empty fruit bunch fiber (EFB) as reinforcement in the unplasticized poly(vinyl chloride) (PVC-U) is a new attraction in the thermoplastic composite technology. The objectives of this study are to investigate the effects of extracted EFB on processability, impact, and flexural properties of PVC-U composites. A soxhlet extraction was used to extract the extractives from the EFB fibers. The identification of the related functional groups present in the concentrated extract was analyzed using FTIR. To produce composites, PVC resin, EFB fiber, and other additives were first dry-blended using a heavy-duty laboratory mixer before being milled into sheets on a two-roll mill. Test specimens were then hot pressed after which the impact and flexural properties were determined. The processability studies of dry blends were carried out using a Brabender Torque Rheometer model PL2200. The FTIR analysis showed that the oil residue was successfully extracted from EFB fibers. Both the extracted and unextracted fibers decreased the fusion time and melt viscosity of PVC-U. However, the extracted fiber was found to increase the fusion time of PVC as the fiber content increased from 10 to 40 phr. The impact and flexural properties of composites were not significantly affected by the fiber extraction.

Mechanical Properties of Benzoylated Oil Palm Empty Fruit Bunch Short Fiber Reinforced Poly(vinyl chloride) Composites

The influence of untreated and benzoylated oil palm empty fruit bunch (OPEFB) short fiber loading on the mechanical properties of the poly(vinyl chloride) (PVC) composite was studied. Benzoylated OPEFB was produced by mixing OPEFB with NaOH solution and agitating vigorously with benzoyl chloride. The PVC resin, various additives, and OPEFB were first dry blended using a laboratory mixer before being milled into sheets on a two-roll mill at 165°C and then hot pressed into composite samples at 180°C. The tensile and impact strength of untreated and benzoylated OPEFB composites decreased whereas the tensile modulus increased with increasing fiber loading from 0 to 40 phr. However, the benzoylated OPEFB was able to improve the tensile properties and impact strength of composites when compared to the untreated fiber. The enhancement of mechanical properties showed that the treatment improved the OPEFB fiber-PVC matrix interfacial adhesion. The improvement of adhesion was clarified by SEM micrographs, the increase of water resistance, and the reduction of glass transition temperature of the composites.

Influence of maleic anhydride-grafted polyethylene compatibiliser on the tensile, oxygen barrier and thermal properties of rice husk and nanoclay-filled low-density polyethylene composite films

Rice husk and nanoclay (montmorillonite)-filled low-density polyethylene composite films were prepared by extrusion blown film. Maleic anhydride-modified polyethylene was used as compatibiliser in various concentrations ranging from 0 to 8 parts per hundred. X-ray difractograms showed an increase in interlayer spacing of montmorillonite from the use of compatibiliser when compared to the uncompatibilised composites; an increase of 20, 33, 36 and 38% for 2, 4, 6 and 8 parts per hundred, respectively, of maleic anhydride-modified polyethylene. With the incorporation of maleic anhydride-modified polyethylene, a better dispersion of the fillers was also achieved, as confirmed by scanning electron microscopy. The compatibilised composite films showed improved tensile and barrier properties. The addition of 4 parts per hundred of the compatibiliser resulted in an improvement by 22% in tensile strength. Furthermore, oxygen barrier property of the composite films improved more than twofold by adding 4 parts per hundred of maleic anhydride-modified polyethylene. This improvement in tensile and barrier properties is due to an increase in the interfacial adhesion between the fibre and matrix and better dispersion of impermeable nanoparticles.

Mechanical and thermal properties of oil palm empty fruit bunch-filled unplasticized poly (vinyl chloride) composites

Awareness of the advantages of natural fibres has stimulated interest in their use to reinforce polymers. One type of natural fibre that is of great relevance to Malaysia is oil palm empty fruit bunches (EFB). To produce EFB-filled unplasticized poly(vinyl chloride) (PVC) composites, PVC resin and the various additives were first dry-blended using a laboratory blender before being milled into sheets on a two-roll mill. Test specimens were then hot pressed, after which the mechanical and thermal properties were determined. Four untreated EFB fibre contents were employed, 10, 20, 30 and 40 phr. The increase in EFB fibre content resulted in an improvement in flexural modulus at the expense of impact strength and flexural strength. The incorporation of EFB slightly enhanced the glass transition temperature but it decreased the thermal stability of the composites, evidenced by a decrease in decomposition temperature and a change in the degradation process from two to three stages.

Development of Scratch- and Abrasion-Resistant Coating Materials Based on Nanoparticles, Cured by Radiation

The aim of this study was to compare the effect of monomers, prepolymers, and nanosilica on the scratch and abrasion resistance of nanocomposite coatings. Ultraviolet (UV) and electron beam (EB) curing were used to cure the nanocomposite coatings. The effect of monomers, prepolymers and nanosilica particles on the viscosity, pendulum hardness, gel content, scratch and abrasion resistance were studied. It was found that the optimum formulation for scratch and abrasion resistance contained 15% Ebecryl 600 epoxy acrylate resin with 30% monomer PETIA and 30% of Aerosil OX-50 nanosilica.

Mechanical Properties of Silane and Zirconate Coupling Agent-Treated Oil Palm Empty Fruit Bunch Fiber-Filled Acrylic-Impact Modified Poly (Vinyl Chloride) Composites

The influence of untreated and treated OPEFB content on the mechanical properties of acrylic impact-modified PVC was investigated. The formulations were first dry blended before being milled into sheets on a two-roll mill. Test specimens were then hot pressed. The modulus significantly increased while the impact and flexural strength insignificantly improved with increasing of treated OPEFB contents. The reduction in water absorption, the formation of new absorption bands and the slight number of treated fiber pulled-out proved that there was an interaction between fiber and matrix. However, this interaction was insufficient to enhance the impact and flexural strength significantly.

Effect of montmorillonite (MMT) content on the mechanical, oxygen barrier, and thermal properties of rice husk/MMT hybrid filler-filled low-density polyethylene nanocomposite blown films

Montmorillonite (MMT)/rice husk (RH) hybrid filler-filled low-density polyethylene (LDPE) nanocomposite films, containing 0, 2, 3, 4, 5, and 6 wt% MMT (based on the total weight) were prepared by extrusion blown film. The films were characterized by morphological, mechanical, oxygen (O2) barrier, and thermal properties. The delamination of MMT layers evidenced from X-ray diffraction results suggests an increase in the interlayer distance and shows intercalated structure of the nanocomposites. Adding MMT did not adversely affect the interfacial morphology, as confirmed by scanning electron microscopy. Addition of MMT into the LDPE/RH system improved the mechanical and O2 barrier properties. For instance, tensile strength, tensile modulus, and tear strength increased by 8, 10, and 5%, respectively, with the addition of 3 wt% MMT. Further, the O2 barrier of the composite films improved more than twofold by adding 4 wt% MMT. Initial degradation temperature of LDPE/RH composites increased with the incorporation of MMT suggesting that the nanocomposites are more thermally stable than LDPE/RH composites.

Tensile, Oxygen Barrier and Biodegradation Properties of Rice Husk-Reinforced Polyethylene Blown Films

The past few years have witnessed a renewed interest in developing new ecofriendly materials, sparked mostly by the nonbiodegradability of most of the polymeric materials. In this context, incorporation of biofibres as load-bearing constituents in polymeric composites is a highly attractive research line for the development of ecofriendly composites. An experimental study, with the overall aim of making environmentally compatible packaging film, was conducted to investigate the influence of rice husk (RH) loading on morphological, tensile, oxygen barrier and biodegradation properties of low-density polyethylene (LDPE)-based extrusion blown films. Various compositions were prepared with varying contents of RH and the properties were correlated with the loading of RH. Morphological observations revealed that there were micro-voids at interface and the RH particles start agglomerating beyond 5 wt%. The tensile, tear and oxygen barrier properties decreased as the loading of RH increased. Soil burial tests revealed that the composite films are biodegradable and RH loading has significant impact on rate of biodegradation.

Flexural and impact properties of poly (vinyl chloride) and acrylic-impact modified poly (vinyl chloride) composite filled with poly (methyl methacrylate) grafted to oil palm empty fruit bunches

Effects of oil palm empty fruit bunch (OPEFB) fiber and OPEFB grafted with poly (methyl methacrylate) on mechanical properties of poly (vinyl chloride) (PVC) and acrylic-impact modified PVC were investigated. The formulations were blended into sheets on a two-roll mill. Test specimens were then hot-pressed. The flexural strength increased, the flexural modulus decreased, and the impact strength relatively constant with the incorporation of grafted fiber. The impact strength of grafted composite improved after acrylic impact modifier (AIM) was added into the grafted composite matrix compared to ungrafted and grafted composite without AIM. The flexural strength and modulus of grafted composite decreased with the addition of AIM.