Khairul Zaman - Academia.edu (original) (raw)

Papers by Khairul Zaman

Bioplastics: The Future of Sustainable Biodegradable Food Packaging

Bio‐based Packaging, 2021

Polymers, 2020

In this study, a mixture of thermoplastic polybutylene succinate (PBS), tapioca starch, glycerol ... more In this study, a mixture of thermoplastic polybutylene succinate (PBS), tapioca starch, glycerol and empty fruit bunch fiber was prepared by a melt compounding method using an industrial extruder. Generally, insertion of starch/glycerol has provided better strength performance, but worse thermal and water uptake to all specimens. The effect of fiber loading on mechanical, morphological, thermal and physical properties was studied in focus. Low interfacial bonding between fiber and matrix revealed a poor mechanical performance. However, higher fiber loadings have improved the strength values. This is because fibers regulate good load transfer mechanisms, as confirmed from SEM micrographs. Tensile and flexural strengths have increased 6.0% and 12.2%, respectively, for 20 wt% empty fruit bunch (EFB) fiber reinforcements. There was a slightly higher mass loss for early stage thermal decomposition, whereas regardless of EFB contents, insignificant changes on decomposition temperature wer...

Scientific Reports, 2020

In this study, it focused on empty fruit brunch (EFB) fibres reinforcement in polybutylene succin... more In this study, it focused on empty fruit brunch (EFB) fibres reinforcement in polybutylene succinate (PBS) with modified tapioca starch by using hot press technique for the use of agricultural mulch film. Mechanical, morphological and thermal properties were studied. Mechanical analysis showed decreased in values of modulus strength for both tensile and flexural testing for fibres insertion. Higher EFB fibre contents in films resulted lower mechanical properties due to poor fibre wetting from insufficient matrix. This has also found evident in SEM micrograph, showing poor interfacial bonding. Water vapour permeability (WVP) shows as higher hydrophilic EFB fibre reinforcement contents, the rate of WVP also increase. Besides this, little or no significant changes on thermal properties for composite films. This is because high thermal stability PBS polymer show its superior thermal properties dominantly. Even though EFB fibres insertion into PBS/tapioca starch biocomposite films have f...

Molecules, 2015

Over the past few decades, there has been an increasing demand for bio-based polymers and resins ... more Over the past few decades, there has been an increasing demand for bio-based polymers and resins in industrial applications, due to their potential lower cost and environmental impact compared with petroleum-based counterparts. The present research concerns the synthesis of epoxidized palm oil acrylate (EPOLA) from an epoxidized palm oil product (EPOP) as environmentally friendly material. EPOP was acrylated by acrylic acid via a ring opening reaction. The kinetics of the acrylation reaction were monitored throughout the reaction course and the acid value of the reaction mixture reached 10 mg KOH/g after 16 h, indicating the consumption of the acrylic acid. The obtained epoxy acrylate was investigated intensively by means of FTIR and NMR spectroscopy, and the

Bioresources

The effects of alkaline treatment and a compatibilizing agent on the tensile properties of sugar ... more The effects of alkaline treatment and a compatibilizing agent on the tensile properties of sugar palm fibre-reinforced high impact polystyrene (HIPS) composites were studied. Two concentrations of an alkali solution (4% and 6%) and two percentages of a compatibilizing agent (2% and 3%) were used in this study. The alkaline treatment was carried out by immersing the fibres in 4% and 6% alkali solutions for 1 hour. A 40 wt. % of sugar palm fibre (SPF) was blended with HIPS and the compatibilizing agent using a Brabender melt mixer at 165 °C. All the treated fiber composites showed tensile strength enhancement compared with untreated composites. The maximum strength increase was 35%, which was achieved by 4% alkali treatment; however, there was no improvement in the tensile modulus.

Effect of Liquid Additives on Graft Copolymerization of Styrene Onto Perirradiated Poly (Ethylene-Co-Tetrafluoroethylene) Films

Key Engineering Materials, 2011

The effect of nano-alumina and radiation on the mechanical properties of high density polyethylen... more The effect of nano-alumina and radiation on the mechanical properties of high density polyethylene hydroxyl apatite composite was investigated. The study showed that nano alumina as filler in the composite enhanced the strength of the polymer matrix and hence improved the mechanical properties of the composite. The study also showed that the mechanical properties of the composite depended on doses of nano alumina used and radiation dose of gamma ray. The maximum radiation dose used in this experiment 100 KGy is the best dose for the composite that enhances the tensile strength, impact, modulus and flexural strength. The interface behavior and strengthening mechanisms are discussed.

The Scientific World Journal, 2012

Ultrahigh-molecular-weight polyethylene/high-density polyethylene (UHMWPE/HDPE) blends prepared u... more Ultrahigh-molecular-weight polyethylene/high-density polyethylene (UHMWPE/HDPE) blends prepared using polyethylene glycol PEG as the processing aid and hydroxyapatite (HA) as the reinforcing filler were found to be highly processable using conventional melt blending technique. It was demonstrated that PEG reduced the melt viscosity of UHMWPE/HDPE blend significantly, thus improving the extrudability. The mechanical and bioactive properties were improved with incorporation of HA. Inclusion of HA from 10 to 50 phr resulted in a progressive increase in flexural strength and modulus of the composites. The strength increment is due to the improvement on surface contact between the irregular shape of HA and polymer matrix by formation of mechanical interlock. The HA particles were homogenously distributed even at higher percentage showed improvement in wetting ability between the polymer matrix and HA. The inclusion of HA enhanced the bioactivity properties of the composite by the formati...

The effect of silane coupling agent to mechanical properties of HDPE/nano-alumina composite was i... more The effect of silane coupling agent to mechanical properties of HDPE/nano-alumina composite was investigated. Nano-alumina used in this study was produced by using sol-gel method. The shape and size of nano-alumina were determined by using TEM. Prior to the usage of nano alumina as a filler in the polymer matrix, (3-methacryloxypropyl) trimethoxysilane (MPS) was used to functionalize the nanoparticles due to its bifunctional nature: hydrolysable group (−Si(OCH3)3) and unsaturated carbon-carbon double bond. The XRD result shows diffraction spectrum of the synthesized nano-alumina. In order to improve the mechanical properties of the composite, nanoalumina was treated with (3methacryloxypropyl) trimethoxysilane (MPS). A high tensile strength, is achieved at 4 wt% of MPS.

Radiation Physics and Chemistry, 2003

The effects of electron beam irradiation on ethylene-tetrafluoroethylene copolymer (ETFE) films w... more The effects of electron beam irradiation on ethylene-tetrafluoroethylene copolymer (ETFE) films were studied. Samples were irradiated in air at room temperature by a universal electron beam accelerator for doses ranging from 100 to 1200 kGy. Irradiated samples were investigated with respect to their chemical structure, thermal characteristics, crystallinity and mechanical properties using FTIR, differential scanning calorimeter (DSC) and universal mechanical tester. The interaction of electron irradiation with ETFE films was found to induce dose-dependent changes in all the investigated properties. A mechanism for electron-induced reactions is proposed to explain the structure-property behaviour of irradiated ETFE films.

Radiation Physics and Chemistry, 2011

Graftcopolymerization of sodiumstyrenesulfonate (SSS) onto electronbeam (EB) irradiated poly(viny... more Graftcopolymerization of sodiumstyrenesulfonate (SSS) onto electronbeam (EB) irradiated poly(vinylidene fluoride) (PVDF) films was investigated to find out a simple preparation process for sulfonic acid proton exchange membranes with respect to monomer concentration, absorbed dose, temperature, film thickness and storage time. The reaction order of the monomer concentration and absorbed dose of grafting was found to be 2.84 and 1.20, respectively. The overall activation energy for graftcopolymerization reaction was calculated to be 11.36 kJ/mol. The initial rate of grafting was found to decrease with an increase in the film thickness. The trapped radicals in the irradiated PVDF films remained effective in initiating the reaction without considerable loss in grafting level up to 180 days, when stored under-60 °C. The presence and distribution of polystyrene sulfonategrafts in the obtained membranes were observed by Fourier transform infrared (FTIR) spectroscopic analysis, scanning optical microscope and scanning transmission electron microscopy (STEM) coupled with X-ray energy dispersive (EDX), respectively.

Mechanical and Electrical Properties of Coconut Coir Fiber-Reinforced Polypropylene Composites

Polymer-Plastics Technology and Engineering, 2005

... 4. Sapuan , SM ; Faiz , M. ; Mohd Zaki , AR Plant based fibre reinforced composites. ... 9. Z... more ... 4. Sapuan , SM ; Faiz , M. ; Mohd Zaki , AR Plant based fibre reinforced composites. ... 9. Zaini , MJ ; My , YA ; Fuad , Z. ; Ismail, Mansor , MS ; Mustafah , J. The effect of filler content and size on the mechanical properties of polypropylene/oil palm wood flour composites . ...

Polymer Degradation and Stability, 2002

The radiation-induced changes taking place in poly(vinylidene fluoride) (PVDF) films exposed to e... more The radiation-induced changes taking place in poly(vinylidene fluoride) (PVDF) films exposed to electron irradiation were investigated in correlation with the applied doses. Samples were irradiated in air at room temperature by a universal electron beam accelerator to doses in the range of 100-1200 kGy. Various properties of the irradiated PVDF films were studied using FTIR, differential scanning calorimetry (DSC) and universal mechanical tester. Unirradiated PVDF film was used as a reference. Electron irradiation was found to induce changes in physical, chemical, thermal, structural and mechanical properties of PVDF films and such changes vary depending on the irradiation dose.

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2003

The effects of electron beam irradiation on two partially fluorinated polymer films i.e. poly(vin... more The effects of electron beam irradiation on two partially fluorinated polymer films i.e. poly(vinylidene fluoride) (PVDF) and poly(ethylene-tetrafluoroethylene) copolymer (ETFE) are studied at doses ranging from 100 to 1200 kGy in air at room temperature. Chemical structure, thermal and mechanical properties of irradiated films are investigated. FTIR show that both PVDF and ETFE films undergo similar changes in their chemical structures including the formation of carbonyl groups and double bonding. The changes in melting and crystallisation temperatures (T m and T c) in both irradiated films are functions of irradiation dose and reflect the disorder in the chemical structure caused by the competition between crosslinking and chain scission. The heat of melting (DH m) and the degree of crystallinity (X c) of PVDF films show no significant changes with the dose increase, whereas those of ETFE films are reduced rapidly after the first 100 kGy. The tensile strength of PVDF films is improved by irradiation compared to its rapid deterioration in ETFE films, which stemmed from the degradation prompted by the presence of radiation sensitive tetrafluoroethylene (TFE) comonomer units. The elongation at break of both films drops gradually with the dose increase indicating the formation of predominant crosslinked structures at high doses. However, the response of each polymer to crosslinking and main chain scission at various irradiation doses varies from PVDF to ETFE films.

Journal of Reinforced Plastics and Composites, 2011

Hybridized kenaf/PALF-reinforced HDPE composite was produced and characterized. Prepared hybrids ... more Hybridized kenaf/PALF-reinforced HDPE composite was produced and characterized. Prepared hybrids were irradiated at various doses of EBI and subsequently with 1%, 2%, and 3% concentrations of vinyltri(2-methoxy ethoxy) silane and TMPTMA as cross-linking agents. The effects of EBI on the mechanical properties of treated and untreated composites were compared. Specimens without cross-linking agents were irradiated using a 2.0 MeV EB accelerator at dose range of 10, 20, 30, 40, 60, 80, and 100 kGy. Thereafter, 10 kGy was selected to irradiate specimens that were prepared with cross-linking agents. Hybrid without the addition of any cross-linking agent showed increase in tensile strength and modulus with increase in radiation dose. Flexural strength, however, showed decline at 80 and 100 kGy. Optimum impact strength was obtained in hybrid prepared without cross-linking agents and at only 10 kGy, while 20 kGy gave superior flexural modulus. Unlike in tensile strength, silane performed better as a cross-linking agent in flexural properties than TMPTMA. Additions of cross-linking agents had less significantly improved the tensile and flexural properties of the hybrid. It was clear that HDPE self-cross-linked by radiation, making silane and TMPTMA less effective. Fractured surfaces of the composites, examined by a scanning electron microscope showed good adhesion between fiber and matrix.

Journal of Polymer Research, 2005

Grafting of acrylamide (AAm) onto oil palm empty fruits bunch fiber using hydrogen peroxide as in... more Grafting of acrylamide (AAm) onto oil palm empty fruits bunch fiber using hydrogen peroxide as initiator and methyl acrylate as comonomer was investigated. The amount of comonomer needed to make grafting of acrylamide possible was determined. The percentage of poly(acrylamide) and the comonomer in the final graft copolymer was estimated by elemental analysis. Results obtained indicated that methyl acrylate facilitated the incorporation of acrylamide monomer onto OPEFB. The reactivity ratios for both monomers were determined by using Fineman-Ross plot. The effects of reaction temperature and period as well as amount of the initiator, solvent, monomer and comonomer on the percentage of grafting at fixed amount of comonomer (11 mmol) were studied. Maximum percentage of grafting was achieved when the amount of initiator and solvent 3.98 × 10 −3 mol and 50 mL respectively. The optimum reaction temperature was 50 • C and the reaction period was 90 min. Highest percentage of grafting was 232% when 25.6 mmol of acrylamide was used under these optimum conditions. The presence of functional group in the grafted polymer is characterized by infrared spectroscopy and the surface morphology is observed by scanning electron microscopy. Thermoanalytic investigation on OPEFB and OPEFB-g-PAAM were carried out to evaluate the thermal stability and respective activation energy of the materials.

Journal of Membrane Science, 2005

Pore-filled polymer electrolyte membranes have been prepared as a potential proton exchange membr... more Pore-filled polymer electrolyte membranes have been prepared as a potential proton exchange membrane by radiation induced grafting using simultaneous technique. The porous substrate films were grafted in a subsequent step after flooding the membranes pores with styrene monomer. The grafted films were then sulfonated in a post grafting reactions. The resulting membranes were characterized by evaluating their physico-chemical properties such as ion exchange capacity, water uptake and proton conductivity as a function of grafting yield. The overall results illustrated that polystyrene grafts is successfully anchored within the pores of PTFE films during grafting and subsequently transformed into hygroscopic proton exchange regions after being sulfonated. The measured conductivity of the sulfonated polystyrene pore-filled electrolyte PTFE membranes achieved were within the magnitude of 10-3 Scm-1 and 10-2 Scm-1 at room temperature and at higher operating temperature, respectively.

Cation exchange membranes by radiation-induced graft copolymerization of styrene onto PFA copolymer films. III. Thermal stability of the membranes

Journal of Applied Polymer Science, 2000

Radiation-grafted cation exchange membranes have shown the potential to be used as separators and... more Radiation-grafted cation exchange membranes have shown the potential to be used as separators and proton conductors in water electrolyzers and SPE fuel cells.13 Considerable work has been recently devoted to develop new cation exchange membranes by radiation-induced ...

Chemical Engineering Journal, 2007

Graft copolymerization of styrene onto electron preirradiated poly(ethylene-co-tetrafluoroethylen... more Graft copolymerization of styrene onto electron preirradiated poly(ethylene-co-tetrafluoroethylene) (ETFE) films was investigated. Effects of reaction conditions: monomer concentration, irradiation dose, temperature, film thickness and storage time on the grafting yield (Y%) were studied. The initial rate of grafting was found to be heavily dependent on the monomer concentration and the irradiation dose and can be represented by the following equation: dG o /dt = k[M o ] 2.0 [D] 0.75. The overall activation energies for graft copolymerization were calculated to be 36.9 and 12.5 kJ/mol below and above 50 • C, respectively. The initial rate of grafting was found to decrease with the increase in the film thickness. The trapped radicals in the irradiated ETFE films were found to be highly effective in initiating grafting reaction up to 240 days when stored under −60 • C. Graft copolymerization in the present study essentially depends on the ability of the monomers to diffuse through the base film and the amount of the trapped radicals.