Lim Bee Ying
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Preferred name
Lim Bee Ying
Official Name
Lim, Bee Ying
Alternative Name
Lim, B. Y.
Lim, Bee Y.
Main Affiliation
Scopus Author ID
57209532691
Researcher ID
DVB-1384-2022

Research Output
Now showing 1 - 10 of 20
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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.

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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.

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Preparation and characterization of tensile properties of PMMA-SiC nanowhiskers nanocomposite films: effect of filler loading and silane treatment

2023-10 , Lim Bee Ying , Voon Chun Hong , L. Y. Lee , Teh Pei Leng , P. Y. Foong

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.

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Effective synthesis of silicon carbide nanotubes by microwave heating of blended silicon dioxide and multi-walled carbon nanotube

2017 , Voo Chung Sung Tony , Voon Chun Hong , Lee Chang Chuan , Lim Bee Ying , Subash Chandra Bose Gopinath , Foo Kai Loong , Mohd Khairuddin Md Arshad , Ruslinda A. Rahim , Uda Hashim , Nashaain Mohd Nordin , Yarub Al-Douri

Silicon carbide nanotube (SiCNTs) has been proven as a suitable material for wide applications in high power, elevated temperature and harsh environment. For the first time, we reported in this article an effective synthesis of SiCNTs by microwave heating of SiO2 and MWCNTs in molar ratio of 1:1, 1:3, 1:5 and 1:7. Blend of SiO2 and MWCNTs in the molar ratio of 1:3 was proven to be the most suitable for the high yield synthesis of β-SiCNTs as confirmed by X-ray diffraction pattern. Only SiCNTs were observed from the blend of MWCNTs and SiO2 in the molar ratio of 1:3 from field emission scanning electron microscopy imaging. High magnification transmission electron microscopy showed that tubular structure of MWCNT was preserved with the inter-planar spacing of 0.25 nm. Absorption bands of Si-C bond were detected at 803 cm-1 in Fourier transform infrared spectrum. Thermal gravimetric analysis revealed that SiCNTs from ratio of 1:3 showed the lowest weight loss. Thus, our synthetic process indicates high yield conversion of SiO2 and MWCNTs to SiCNTs was achieved for blend of SiO2 and MWCNTs in molar ratio of 1:3.

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Microwave welding with SiCNW/PMMA nanocomposite thin films: enhanced joint strength and performance

2025-01 , Phey Yee Foong , Voon Chun Hong , Lim Bee Ying , Foo Wah Low , Teh Pei Leng , Nor Azizah Parmin , Subash Chandra Bose Gopinath , Veeradasan Perumal , Yeoh Cheow Keat , Nor Azura Abdul Rahim

Most previously reported susceptors for microwave welding are in powder form. In this study, a thin-film susceptor was employed due to its uniform heating rate and ease of handling. Silicon carbide nanowhisker (SiCNW) were incorporated into a poly(methyl methacrylate) (PMMA) matrix to create a nanocomposite thin film, which served as the susceptor. The microwave welding process involved three straightforward steps: fabrication of the PMMA/SiCNW nanocomposite thin film, application of the nanocomposite film to the target area, and subsequent microwave heating. Upon cooling, a robust microwave-welded joint was formed. The mechanical properties and microstructure of the welded joints were characterized using single-lap shear tests, three-point bending tests, and scanning electron microscopy. Results demonstrated that the shear strength and elastic modulus of the welded joints were optimized with increased heating time and SiCNW filler loading. This optimization is attributed to the formation of a SiCNW-filled polypropylene (PP) nanocomposite layer of increasing thickness at the welded joint interface. However, the incorporation of SiCNW also constrained the mobility of the PP chains, reducing the joint’s flexibility. Furthermore, the welded joint formed with the PMMA/SiCNW nanocomposite thin-film susceptor exhibited an 18.82% improvement in shear strength compared to joints formed with a powdered SiCNW susceptor. This study not only demonstrates the potential of PMMA/SiCNW nanocomposite thin films as efficient susceptors for microwave welding but also paves the way for developing high-performance polymer-based composite joints with improved mechanical properties for applications in the automotive, aerospace, and construction industries.

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Feasibility Study of Microwave Welding of Polypropylene Using Silicon Carbide Nanowhiskers as Microwave Susceptor

2023-01-01 , Foong P.Y. , Voon Chun Hong , Lim Bee Ying , Teh P.L. , Mohd Afendi Rojan

Currently, welding is the most efficient way for joining of plastic. Due to its rapid heating, efficiency in term of time and energy, and ability to be applied on components of any shape, microwave welding stands out from other welding methods. Additionally, SiCNWs was proposed as the microwave susceptor for the microwave welding of thermoplastic in this work due to its high dielectric loss and biocompatibility. To produce microwave welded joint, SiCNWs was first mixed with acetone to obtain a SiCNWs suspension. After that, SiCNWs was drop casted onto the targeted area of PP, allowed to dry and then microwave irradiated. In this work, the microwave heating time studied ranged from 15 s to 20 s. SEM and single lap shear test were used to characterise the microwave welded joint. From the findings, the tensile strength increased as the microwave heating duration increased from 15 s to 18 s, due to formation of SiCNWs/PP nanocomposite welded joint layer with increasing thickness. Yet, when the microwave heating time was prolonged to 20 s, the tensile strength decreased to 0.85 MPa. Besides, a void was observed at the welded joint and it is believed that the presence of void causes the welded joint to weaken when force is applied. Under properly regulated of microwave heating time, a strengthened nanocomposite welded joint can be produced which demonstrate great promise in plastic welding.

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Effect of dispersing agents on the electrical and mechanical performance of GNPs filled epoxy nanocomposite

2023-07 , Wong Wee Chun , Teh Pei Leng , Yeoh Cheow Keat , Azlin Fazlina Osman , Lim Bee Ying , Mohamad Syahmie Mohamad Rasidi

In this work, graphene nanoplatelets (GNPs) filled epoxy nanocomposites with the addition of different dispersing agents were fabricated using a method combines mechanical mixing and tip sonication. The loading of GNPs used is 0.8 vol% determined previously as the amount required to achieve the percolation threshold to conduct electricity. Three dispersing agents were used in this work: Sodium dodecyl sulphate (SDS), ethanol and Phenyl glycidyl ether (PGE), with loadings varying from 2 vol% to 10 vol%. The incorporation of dispersing agent enhanced the electrical bulk conductivity of GNPs filled nanocomposites. The mechanical performance (flexural properties and fracture toughness) of the nanocomposite were evaluated and compared. The optimum loading of SDS to obtain the highest flexural strength and fracture toughness is 2 vol%, where further increases will deteriorate the performance of nanocomposites. On the other hand, the optimum loading of ethanol and PGE are 4 vol%. The fracture toughness of GNPs filled nanocomposites improved with the addition of 2 vol% SDS and deteriorated with increasing loadings of SDS up to 10 vol%. By incorporating 4 vol% of ethanol, the optimum fracture toughness of the nanocomposite is achieved. Fracture toughness is then dropped with further increases in ethanol. The addition of PGE caused deterioration in fracture toughness of GNPs filled epoxy nanocomposite.

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Effect of dispersibility of graphene nanoplatelets on the properties of natural rubber latex composites using sodium dodecyl sulfate

2022-01-01 , Che W.M. , Teh Pei Leng , Yeoh Cheow Keat , Jalilah Abd Jalil , Lim Bee Ying , Rasidi M.S.M.

Natural rubber latex/graphene nanoplatelet (NRL/GNP) composites containing GNP-pristine and GNP-SDS were prepared by a simple mechanical mixing method. The main objective was to study the effect of dispersibility of GNP on the properties in NRL. X-ray diffraction confirmed the adsorption of sodium sulfate dodecyl (SDS) on the GNP surface. The results showed that high filler loading diminished the physical and mechanical properties of the composites but successfully endured to satisfy electrical conductivity to the NRL/GNP composites. Besides, the SDS surfactant-filled system demonstrated better physical, tensile, electrical, and thermal stability properties than the GNP-pristine. The intercalated and dispersed GNP-SDS increased the number of routes for stress and heat transfer to occur and facilitated the formation of conductive pathways as well, leading to the improvement of the properties as compared to NRL/GNP-pristine composites. However, as the GNP-SDS loading exceeded 5 phr, the GNP-SDS localized in the interstitial layer of NRL, restricted the formation of crosslinking, and interfered with the strain-induced crystallization ability of the composites.

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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.

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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.

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