Voon Chun Hong
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Preferred name
Voon Chun Hong
Official Name
Hong, Voon Chun
Alternative Name
Voon, C. H.
Voon, Chun Hong
Hong, Voon Chun
Hong, V. C.
Main Affiliation
Scopus Author ID
55334719400
Researcher ID
D-2050-2015

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  • Publication
    Effect of solvent on mechanical and physical properties of PMMA/Sic composite films
    ( 2024-12)
    Auni Fakhira Che Baharudin
    ;
    Lim Bee Ying
    ;
    Voon Chun Hong
    ;
    Teh Pei Leng
    ;
    Tan Soo Jin
    The selection of solvent in solution casting is crucial as it may affect the morphology and properties of the resulting composite films. In this study, the effect of solvent on the properties of poly(methyl methacrylate)/silicon carbide (PMMA/SiC) composite films was investigated. By using acetone, the solution casting was carried out at various solvent-to-solid (S/S) ratio, from 4:1 to 10:1 at room temperature. It was found that the increasing S/S ratio enhanced the tensile strength and modulus of elasticity of pristine PMMA films but deteriorated its elongation at break, up to 8:1 ratio. The crystallinity of the PMMA films was found to increase with S/S ratio, as confirmed by the higher peak intensity in X-Ray Diffraction (XRD) patterns and the SEM micrographs. In the second part of the study, by using S/S ratio of 8:1, the nano sized SiC (0.25 wt%) was added as a filler into PMMA and toluene with different ratio was added as a secondary solvent. The addition of SiC has increased the tensile strength and modulus of elasticity of PMMA/SiC but decreased its elongation at break. However, the presence of toluene reduced the tensile strength of the PMMA/SiC composite films and resulting in rougher tensile fracture surfaces as shown in SEM micrographs. The toluene with nonpolar nature had affected the distribution of SiC in PMMA. It can be concluded that the properties of the PMMA composites films can be tailored according to the needs of applications.
  • Publication
    Functionalized carbon black in epoxy composites: effect of single- and dual-matrix systems
    ( 2022-07-01)
    Phua J.L.
    ;
    Teh Pei Leng
    ;
    Yeoh C.K.
    ;
    Voon Chun Hong
    Functionalized carbon black (CB) using three different surface modification methods: wet oxidation, epoxy monomer impregnation, and air oxidation, in single-epoxy composites and dual-matrix epoxy/poly(methyl methacrylate) PMMA composites at 15 vol% of CB content was studied in this research. The characterization on the surface modification CB was done via Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller (BET), and thermal gravimetric analysis. The phenol or ether, carboxylic acid, and epoxide functional groups were found on CB after surface modifications, along with a change in structure and BET surface area. Thermal degradation of CB was different after surface modification. This study further investigated the effect of the addition of surface-modified CB into epoxy resin, where the state of dispersion and distribution was observed under scanning electron microscopy. After surface modification, the mechanical testing via flexural and fracture toughness was done, where improvement was observed. A minor decrease in the electrical bulk conductivity of the composites was measured, which was due to a reduction in the degree of agglomeration. Both the thermal stability and CTE of surface-modified CB-filled epoxy composites show a decrement. Graphic abstract: Chemical modification of CB using air oxidation, wet oxidation, and epoxy monomer impregnation methods.[Figure not available: see fulltext.]
  • Publication
    Microwave welding of thermoplastic using silicon carbide nanowhiskers as susceptor effect of heating duration
    ( 2024-06)
    Phey Yee Foong
    ;
    Voon Chun Hong
    ;
    Lim Bee Ying
    ;
    Teh Pei Leng
    ;
    Yeoh Cheow Keat
    ;
    Mohd Afendi Rojan
    ;
    Nor Azizah Parmin
    ;
    Subash Chandra Bose Gopinath
    ;
    Foo Wah Low
    ;
    Muhammad Kashif
    ;
    Nor Azura Abdul Rahman
    ;
    Sam Sung Ting
    ;
    Veeradasan Perumal
    Microwave welding is becoming more popular than conventional joining methods due to its advantages such as rapid and localised heating as well as applicable to components with complicated geometry. Previously reported susceptor, such as carbonaceous materials and conductive polymers, are toxic and the welding process involving these susceptors is time-consuming. Because of its exceptional microwave absorption and biocompatibility, silicon carbide nanowhiskers (SiCNWs) was employed as the microwave susceptor for microwave welding. Microwave welding in this study comprises of only three simple steps: SiCNWs suspension preparation, SiCNWs application and microwave heating. The weld strength of welded joint was then characterised using tensile test and energy dispersive x-ray spectroscopy equipped scanning electron microscopy (EDS-SEM) to study its mechanical properties and cross-section microstructure. The influence of microwave irradiation time was studied in this study, and it is found that the weld strength rose with the extension of microwave irradiation time, until a maximum weld strength of 1.61 MPa was achieved by 17 s welded joint. The development of SiCNWs reinforced PP nanocomposite welded joint layer is responsible for the enhanced weld strength. Prolonged heating duration may also result in flaws such as void formation at the welded joint, which subsequently lowered the weld strength to 0.60 MPa when the heating duration was extended to 20 s. In sum, a strengthen welded joint can be formed with rapid microwave heating under the proper control of heating duration.
  • Publication
    Preparation and Characterization of Tensile Properties of PMMA/SiC Nanowhiskers Nanocomposite Films: Effect of Filler Loading and Silane Treatment
    ( 2023-10-01)
    Lim Bee Ying
    ;
    Voon Chun Hong
    ;
    Lee L.Y.
    ;
    Teh Pei Leng
    ;
    Foong P.Y.
    The preparation of nanocomposites through melt mixing was challenging as the nanofillers tend to form agglomeration. The silicon carbide nanowhiskers (SiCNWs) filled poly (methyl methacrylate) (PMMA) thin film in this study was prepared by means of solution casting. Acetone with low toxicity was used as solvent to dissolve the PMMA pellets. A coupling agent, silane was used to enhance the properties of composite films. Besides, the untreated and treated SiCNWs were filled into PMMA matrix, respectively with the filler loading varied from 0.2 to 0.8 wt%. The universal testing machine was used to investigate the tensile properties of composites. It was found out that the tensile strength of the PMMA was reduced in the presence of SiCNWs. However, the tensile strength had increased with the rise of filler loading. At 0.8 wt% of SiCNWs, the composites’ tensile strength was comparable to virgin PMMA. Meanwhile, the SiCNWs had reduced the elongation at break but increased the elastic modulus of PMMA/SiCNWs nanocomposite films. In addition, silane surface treatment on SiCNWs had improved the tensile strength and ductility but lowered the elastic modulus of the nanocomposites. The improvement was due to the enhancement of interfacial adhesion between SiCNWs and PMMA.
  • Publication
    Effect of silicone rubber on the properties of epoxy/recovered carbon black (rCB) conductive materials
    ( 2024-04)
    Pei Chee Leow
    ;
    Teh Pei Leng
    ;
    Yeoh Cheow Keat
    ;
    Wee Chun Wong
    ;
    Chong Hooi Yew
    ;
    Xue Yi Lim
    ;
    Kai Kheng Yeoh
    ;
    Nor Azura Abdul Rahim
    ;
    Voon Chun Hong
    The primary focus of this study is to investigate the effect of silicone rubber (SR) content on the mechanical, thermal, electrical conductivity, and morphological properties of epoxy/recovered carbon black (rCB) conductive material. The conductive material is used to produce the electrostatic discharge (ESD) tray for the electronic packaging industry. This study investigated the effect of silicone rubber content (0, 5, 10, 15, and 20 vol.%) on the properties of epoxy/SR/rCB conductive materials, with the rCB content fixed at 15 vol.% for its optimum electrical conductivity. The silicone rubber acts as a toughening agent for epoxy. Through the fracture toughness result, it can be identified that silicone rubber plays a role in improving the toughness properties of the epoxy/SR/rCB conductive material. The optimum results for mechanical properties were recorded at 5 vol.% SR. The addition of SR to the epoxy matrix enhances the electrical properties of the epoxy/SR/rCB conductive material. The effect of thermal aging on epoxy/SR/rCB conductive materials was also studied to determine the properties of the conductive material materials at high temperatures for a long period of time. After thermal aging, the mechanical, thermal, electrical conductivity, and morphological properties of the epoxy/SR/rCB conductive material were slightly reduced.
  • Publication
    The effect of coated calcium carbonate using stearic acid on the recovered carbon black masterbatch in low-density polyethylene composites
    ( 2023-01-01)
    Leow V.J.
    ;
    Teh Pei Leng
    ;
    Yeoh C.K.
    ;
    Nor Azura Abdul Rahim
    ;
    Wong W.C.
    ;
    Voon Chun Hong
    ;
    Mohamed Rasidi M.S.
    ;
    Lim Bee Ying
    This research focuses on recycling rubber tire waste through pyrolysis to produce recovered carbon black (rCB). The rCB is combined with recycled low-density polyethylene (rLDPE), calcium carbonate (CaCO3), fatty acid, metallic stearate, and polyethylene (PE) wax to create an rCB masterbatch for household packaging. Surface modification of CaCO3 particles using stearic acid improves the compatibility with LDPE. The study investigates mechanical properties, morphology, melt flow index (MFI), X-ray diffraction, and thermogravimetric analysis in three systems: uncoated, coated, and a hybrid combination of coated and uncoated CaCO3 in LDPE/rCB masterbatch composites. The coated system demonstrates higher mechanical properties and improved compatibility between CaCO3 and LDPE. All three systems exhibit enhanced thermal stability and MFI compared to virgin LDPE, with the coated system showing the most significant improvement. The study showcases the potential of LDPE/rCB masterbatch composites for household packaging, with the coated system displaying the optimum performance across various characteristics.
  • Publication
    Effect of solvent to matrix weight ratio and stearic acid treatment on the mechanical properties of Poly (methyl methacrylate)/ palm kernel shell composites
    ( 2021-07-21)
    Lim Bee Ying
    ;
    Voon Chun Hong
    ;
    Lye S.F.
    ;
    Teh Pei Leng
    In this study, poly (methyl methacrylate)/palm kernel shell (PMMA/PKS) composites were prepared by solution casting. The effect of solvent to matrix (S/M) weight ratio and stearic acid (SA) treatment on PMMA/PKS composites were studied. PMMA pellets were dissolved and PKS powders were dispersed into acetone, separately. PMMA solution and PKS suspension were then mixed in ultrasonic bath. The mixture was then poured into a glass petri dish to evaporate acetone at room temperature and finally PMMA/PKS composite thin film was obtained. PMMA/PKS composites were characterized by using SEM and were subjected to tensile test. It was found that tensile strength, modulus of elasticity of composite increased but elongation at break decreased with the increasing S/M ratio and with SA treatment. The improvement of the mechanical properties was due to the improved interfacial bonding following the SA treatment and the formation of crystallized PMMA domain in the composite with the increasing S/M ratio. SEM images revealed even fracture surfaces as S/M increased and with the application of SA treatment that indicate better matrix-filler adhesion. It can be concluded that S/M increment and SA treatment improved mechanical properties of PMMA/PKS composite.
  • Publication
    A comparative study of microwave welding using multiwalled carbon nanotubes and silicon carbide nanowhiskers as microwave susceptors
    ( 2024-10)
    Phey Yee Foong
    ;
    Voon Chun Hong
    ;
    Lim Bee Ying
    ;
    Teh Pei Leng
    ;
    Yeoh Cheow Keat
    ;
    Mohd Afendi Rojan
    ;
    Nor Azizah Parmin
    ;
    Subash Chandra Bose Gopinath
    ;
    Foo Wah Low
    ;
    Muhammad Kashif
    ;
    Nor Azura Abdul Rahman
    ;
    Sam Sung Ting
    ;
    Veeradasan Perumal
    Recently, microwave welding has arisen as an advanced joining method due to its versatility and rapid heating capabilities. Among others, microwave susceptors play a crucial role in microwave welding, as different classes of microwave susceptors have distinct microwave heating mechanisms. In this work, polypropylene (PP) was utilized as a thermoplastic substrate and two types of microwaves susceptors, namely multiwalled carbon nanotubes (MWCNTs) and silicon carbide nanowhiskers (SiC NWs), were studied for microwave welding. The susceptor was first dispersed in acetone to form susceptor suspension. Next, the susceptor suspension was deposited onto the targeted area on substrate and paired with another bare PP substrate. The paired sample was then exposed to 800 W microwave radiation in a microwave oven. Afterward, the welded joint was evaluated using a tensile test and scanning electron microscopy to determine its joint strength and cross-section microstructure. The results showed that the joint strength increased as the heating duration increased. The welded joint formed using MWCNTs achieved a maximum strength of 2.26 MPa when 10 s was used, while the SiC NWs-formed welded joint achieved a maximum strength of 2.25 MPa at 15 s. This difference in duration in forming a complete welded joint can be attributed to the higher microwave heating rates and thermal conductivity of MWCNTs. However, increasing the heating duration to 20 s caused severe deformation at the welded joint and resulted in low joint strength. Overall, this study highlights the significance of understanding the microwave heating mechanism of different susceptors and provides essential insight into the selection of a microwave susceptor for microwave welding.
  • Publication
    Comparison study: The effect of unmodified and modified graphene nano-platelets (GNP) on the mechanical, thermal, and electrical performance of different types of GNP-filled materials
    ( 2021-09-01)
    Ka Wei K.
    ;
    Teh Pei Leng
    ;
    Yeoh Cheow Keat
    ;
    Hakimah Osman
    ;
    Sullivan M.
    ;
    Voon Chun Hong
    ;
    Lim Bee Ying
    ;
    Mohamad Syahmie Mohamad Rasidi
    Graphene nano-platelet (GNP) nano-fillers were successfully covalently functionalized with carboxylic and epoxide groups as proven by Fourier-transform infrared spectroscopy. This paper reports the effect of unmodified and modified GNP nano-fillers on the mechanical, thermal, and electrical performance of GNP-filled materials. The results show that the mechanical properties of GNP-filled materials were enhanced with a modified GNP nano-filler. Among the GNP-filled materials, the modified epoxy/NR/GNP compatibilized material shows higher flexural and toughness properties. The modified GNP nano-filler has reduced the thermal stability of the modified compatibilized material. This is because the oxygen-containing groups (C–O–C and –COOH) on the surfaces of modified GNP nano-fillers have lower thermal stability; which accelerates the thermal decomposition of the modified material. Modified compatibilized material shows higher electrical conductivity than the unmodified compatibilized material. X-ray diffraction results proved that d-spacing of modified GNP nano-fillers in modified compatibilized material was shortest when compared to unmodified GNP nano-fillers in unmodified compatibilized material, thus, allowing more electrons to travel at a faster rate through the conductive pathways.
  • Publication
    Dielectric and mechanical properties of PLA-carbon composites
    ( 2024-04)
    Mathanesh Thangarajan
    ;
    Yeoh Cheow Keat
    ;
    Teh Pei Leng
    ;
    Wee Chun Wong
    ;
    Chong Hui Yew
    ;
    Kang Zheng Khor
    ;
    Nor Azura Abdul Rahim
    ;
    Voon Chun Hong
    This study focuses on the development and characterization of Carbon-based Polylactide (PLA) composites for 3D printer filaments. The aim is to enhance the electrical and mechanical properties of PLA by incorporating recovered carbon black (RCB) in different mesh sizes (500, 1000, 1500, and 2000 mesh). Electrical impedance spectroscopy and dielectric constant measurements were performed to investigate the electrical properties of the composites. Results showed that the addition of RCB increased the dielectric constant, with values ranging from 2.5 to 7.1, indicating improved electrical performance. Scanning electron microscopy (SEM) analysis revealed the dispersion of carbon particles within the composites, enhancing their electrical conductivity. The effect of RCB particle size on electrical properties was also explored, with smaller particle sizes (2000 mesh) resulting in the highest conductivity of 6.2 S/m. Tensile testing demonstrated that the addition of RCB increases the tensile strength of PLA, with values ranging from 28.6 MPa to 47.2 MPa, and the elastic modulus, ranging from 832 MPa to 1.56 GPa, depending on the mesh size. The optimal combination of RCB content and mesh size resulted in a composite with a tensile strength of 43.8 MPa. Overall, this research provides insights into the development of Carbon-based PLA composites with improved electrical and mechanical properties.