Mohd Firdaus Omar
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Mohd Firdaus Omar
Official Name
Mohd Firdaus, Omar
Alternative Name
Omar, Mohd Firdaus
Mohd, Firdaus Omar
Omar, M. F.
Omar, Mohdfirdaus
Omar, Mohd F.
Main Affiliation
Scopus Author ID
36149536300
Researcher ID
U-8459-2019

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  • Publication
    The effect of synthesis parameter On HKUST-1 nanocomposites studied by FTIR characterisation and mechanical testing
    ( 2024-12)
    Syazwana Ahmad
    ;
    Mohd Firdaus Omar
    ;
    Khairul Anwar Abdul Halim
    ;
    Shayfull Zamree Abd. Rahim
    ;
    Sam Sung Ting
    ;
    E. M. Mahdi
    ;
    Hazizan Md Akil
    ;
    Muhammad Hafiz Hassan
    ;
    Norlin Nosbi
    ;
    Nurfina Yudasari
    In the present work, Hong Kong University of Science and Technology (HKUST-1) has been synthesised at room temperature with 1:0, 1:1 and 0:1 ratio of ethanol and water and reinforced into polyurethane. In order to understand the impact of synthesis parameters on HKUST-1 nanocomposites, an investigation was conducted using FTIR characterisation and mechanical testing. The objective was to examine the potential improvement of the reinforced polymer. The mechanical testing results were shown to be significantly influenced by the presence of HKUST-1 with 1:0 ratio of ethanol and water (sample A) into polyurethane (PU). The samples underwent Fourier Transform Infrared Spectroscopy (FTIR) analysis to determine the types of bonds within the polymer-MOF nanocomposites. It was observed that the reinforced nanoparticles did not undergo any chemical changes, as indicated by the recorded spectra, which can be related to the overlapping characteristics of HKUST-1 and PU. The findings indicate that the A/PU exhibited a notable impact in comparison to other materials, as evidenced by the results of the tensile test and nanoindentation study.
  • Publication
    Mechanical and dielectric properties of hybrid carbon nanotubes-woven glass fibre reinforced epoxy laminated composites via the electrospray deposition method
    ( 2021)
    Muhammad Razlan Zakaria
    ;
    Nur Aishahatul Syafiqa Mohammad Khairuddin
    ;
    Mohd Firdaus Omar
    ;
    Hazizan Md Akil
    ;
    Muhammad Bisyrul Hafi Othman
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Shayfull Zamree Abd. Rahim
    ;
    Sam Sung Ting
    ;
    Azida Azmi
    Herein, the effects of multi-walled carbon nanotubes (CNTs) on the mechanical and dielectric performance of hybrid carbon nanotube-woven glass fiber (GF) reinforced epoxy laminated composited are investigated. CNTs are deposited on woven GF surface using an electrospray deposition method which is rarely reported in the past. The woven GF deposited with CNT and without deposited with CNT are used to produce epoxy laminated composites using a vacuum assisted resin transfer moulding. The tensile, flexural, dielectric constant and dielectric loss properties of the epoxy laminated composites were then characterized. The results confirm that the mechanical and dielectric properties of the woven glass fiber reinforced epoxy laminated composited increases with the addition of CNTs. Field emission scanning electron microscope is used to examine the post damage analysis for all tested specimens. Based on this finding, it can be prominently identified some new and significant information of interest to researchers and industrialists working on GF based products
  • Publication
    Room Temperature Synthesis and Characterization of HKUST-1, Metal–Organic Frameworks (MOFs)
    ( 2023-01-01)
    Ahmad S.
    ;
    Mohd Firdaus Omar
    ;
    Mahdi E.M.
    ;
    Khairul Anwar Abdul Halim
    ;
    Shayfull Zamree Abd. Rahim
    ;
    Sam Sung Ting
    ;
    Md. Akil H.
    ;
    Nosbi N.
    In the present work, HKUST-1 has been synthesized at room temperature with 1:0, 1:1, and 0:1 ratio of ethanol and water. A wide range of reaction conditions were explored in order to understand the effects of solvent and temperature. It was discovered that various precursors yielded products with various BET specific surface areas. The effect of water may therefore be explained by the decrease in reaction rate with an increasing concentration of reactants. The XRD data and SEM analysis showed that both MOFs were very crystalline in the product.
      1
  • Publication
    Influence of filler surface modification on static and dynamic mechanical responses of rice husk reinforced linear low-density polyethylene composites
    ( 2022-01-01)
    Mohd Firdaus Omar
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Sam Sung Ting
    ;
    Jez B.
    ;
    Nabialek M.
    ;
    Akil H.M.
    ;
    Nik Noriman Zulkepli
    ;
    Shayfull Zamree Abd. Rahim
    ;
    Azmi A.
    Filler surface modification has become an essential approach to improve the compatibility problem between natural fillers and polymer matrices. However, there is limited work that concerns on this particular effect under dynamic loading conditions. Therefore, in this study, both untreated and treated low linear density polyethylene/rice husk composites were tested under static (0.001 s-1, 0.01 s-1and 0.1 s-1) and dynamic loading rates (650 s-1, 900 s-1and 1100 s-1) using universal testing machine and split Hopkinson pressure bar equipment, respectively. Rice husk filler was modified using silane coupling agents at four different concentrations (1, 3, 5 and 7% weight percentage of silane) at room temperature. This surface modification was experimentally proven by Fourier transform infrared and Field emission scanning electron microscopy. Results show that strength properties, stiffness properties and yield behaviour of treated composites were higher than untreated composites. Among the treated composites, the 5% silane weight percentage composite shows the optimum mechanical properties. Besides, the rate of sensitivity of both untreated and treated composites also shows great dependency on strain rate sensitivity with increasing strain rate. On the other hand, the thermal activation volume shows contrary trend. For fracture surface analysis, the results show that the treated LLDPE/RH composites experienced less permanent deformation as compared to untreated LLDPE/RH composites. Besides, at dynamic loading, the fracture surface analysis of the treated composites showed good attachment between RH and LLDPE.
      1
  • Publication
    Thermal properties of nanocellulose‐reinforced composites: a review
    ( 2019)
    P. G. Gan
    ;
    Sam Sung Ting
    ;
    Muhammad Faiq Abdullah
    ;
    Mohd Firdaus Omar
    Nanocellulose has received increasing attention in science and industry in recent years as a nanoscale material for the reinforcement of polymer matrix composites due to its superior mechanical properties, renewability, and biodegradability. New nanocellulose sources, modifications, and treatments are under development to reduce the high energy required during production and to create a more suitable industrial-scale production process. Thus, this paper reviews plant-based nanocellulose composites and their properties, with a focus on their thermal-related characteristics. The purpose of this review is to establish for readers the impact of the incorporation of nanocellulose on the thermal and dynamic mechanical properties of nanocellulose composites. Understanding of the thermal properties is important for researchers to assess the suitability of the nanocomposites for a variety of applications in response to new and evolving societal requirements.
      94  29
  • Publication
    Comparative study on the properties of cross-linked cellulose nanocrystals/chitosan film composites with conventional heating and microwave curing
    ( 2020-12-20)
    Gan P.G.
    ;
    Sam Sung Ting
    ;
    Muhammad Faiq Abdullah
    ;
    Mohd Firdaus Omar
    ;
    Tan W.K.
    Cross-linking of chitosan film composites was carried out by using conventional heating and microwave curing methods in this study. Non-cross-linked and glutaraldehyde (GA) cross-linked neat chitosan and cellulose nanocrystals (CNC)/chitosan film composites were cured by either conventional oven heating or microwave irradiation. Tensile strength and Young's modulus of chitosan composites were enhanced significantly by the addition of CNC and GA especially for the microwave-cured samples. The changes in chemical interaction of the chitosan film composites was determined by Fourier transform infrared (FTIR) spectroscopy. The microwave-cured GA-cross-linked chitosan film composites were more thermally stable than non-cross-linked and conventionally heated GA-cross-linked chitosan film composites due to the formation of a more stable structure between GA and chitosan. Nevertheless, the reduced antimicrobial efficacy of film composites against Escherichia coli, Bacillus subtilis, and Saccharomyces cerevisiae was observed in cross-linked film composites compared with non-cross-linked composites.
      1
  • Publication
    Influence of filler surface modification on static and dynamic mechanical responses of rice husk reinforced linear low-density polyethylene composites
    ( 2021)
    Mohd Firdaus Omar
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Sam Sung Ting
    ;
    B. Jeż
    ;
    M. Nabiałek
    ;
    Hazizan Md Akil
    ;
    Nik Noriman Zulkepli
    ;
    Shayfull Zamree Abd. Rahim
    ;
    Azida Azmi
    Filler surface modification has become an essential approach to improve the compatibility problem between natural fillers and polymer matrices. However, there is limited work that concerns on this particular effect under dynamic loading conditions. Therefore, in this study, both untreated and treated low linear density polyethylene/rice husk composites were tested under static (0.001 s –1, 0.01 s –1 and 0.1 s –1) and dynamic loading rates (650 s –1, 900 s –1 and 1100 s –1) using universal testing machine and split Hopkinson pressure bar equipment, respectively. Rice husk filler was modified using silane coupling agents at four different concentrations (1, 3, 5 and 7% weight percentage of silane) at room temperature. This surface modification was experimentally proven by Fourier transform infrared and Field emission scanning electron microscopy. Results show that strength properties, stiffness properties and yield behaviour of treated composites were higher than untreated composites. Among the treated composites, the 5% silane weight percentage composite shows the optimum mechanical properties. Besides, the rate of sensitivity of both untreated and treated composites also shows great dependency on strain rate sensitivity with increasing strain rate. On the other hand, the thermal activation volume shows contrary trend. For fracture surface analysis, the results show that the treated LLDPE/RH composites experienced less permanent deformation as compared to untreated LLDPE/RH composites. Besides, at dynamic loading, the fracture surface analysis of the treated composites showed good attachment between RH and LLDPE.
      2  11
  • Publication
    Insight on the structural aspect of ENR-50/TiO2 hybrid in KOH/C3H8O medium revealed by NMR spectroscopy
    ( 2020)
    Omar S. Dahham
    ;
    Rosniza Hamzah
    ;
    Mohamad Abu Bakar
    ;
    Nik Noriman Zulkepli
    ;
    Abdulkader M. Alakrach
    ;
    Sam Sung Ting
    ;
    Mohd Firdaus Omar
    ;
    Tijjani Adam
    ;
    Awad A. Al-rashdi
    The ring-opening reactions (ROR) of epoxide groups in epoxidized natural rubber/titania (ENR-50/TiO2) hybrid in potassium hydroxide/isopropanol medium were examined using NMR spectroscopy and supported by the FTIR technique. The thermal behaviour of the hybrid was also studied using TG/DTG and DSC analyses. The 1H NMR results suggested that 16.82% of ROR occurred in the hybrid, while the 13C NMR results exhibited five new peaks at δ 19.5, 71.0, 73.7, 91.7 and 94.4 ppm in the hybrid. 2D NMR, such as HMQC, HMBC and COSY techniques, further scrutinized these assignments. The FTIR spectrum exhibited Ti-O-C characteristics via the peak at 1028 cm−1. The TG/DTG results showed four steps of thermal degradation at 44–148, 219–309, 331–489 and 629–810 °C due to the existence of Ti moieties along with a polymer chain mixture (intact and ring-opened epoxide groups) of ENR-50, which in turn led to an increase in the Tg value of the hybrid to 27 °C compared to that of purified ENR-50 at −17.72 °C.
      4  12
  • Publication
    An alkaline deep eutectic solvent based on potassium carbonate and glycerol as pretreatment for the isolation of cellulose nanocrystals from empty fruit bunch
    ( 2020-02-01)
    Gan P.G.
    ;
    Sam Sung Ting
    ;
    Muhammad Faiq Abdullah
    ;
    Mohd Firdaus Omar
    ;
    Tan L.S.
    Cellulose nanocrystals (CNC) were successfully isolated from oil palm empty fruit bunch (EFB) using sulphuric acid hydrolysis preceded by alkaline deep eutectic solvent (DES) pretreatment and bleaching. In this study, an alkaline DES consisting of potassium carbonate and glycerol (molar ratio of 1:7) was used as the pretreatment solvent to promote the dissolution of lignin and hemicellulose. The processing parameters of acid hydrolysis were optimized using Box-Behnken Design. The results showed that the yield of CNC was 37.1%, under the optimal conditions of 60.0 wt% acid concentration at 46.1 °C for 58.5 min. The field emission scanning electron microscopy (FESEM), chemical composition analysis, and Fourier transform infrared (FTIR) results indicated that unwanted impurities, such as hemicellulose and lignin, were efficiently eliminated from the raw EFB fibers by DES pretreatment and bleaching. The average diameter of CNC was less than 10 nm. The raw EFB fiber, treated cellulose, and CNC showed crystallinities of 38.7%, 51.2%, and 65.3%, respectively. The CNC had lower thermal stability, which was ascribed to the sulphate group present on the CNC surface.
      1
  • Publication
    Mechanical and dielectric properties of hybrid carbon nanotubes-woven glass fibre reinforced epoxy laminated composites via the electrospray deposition method
    ( 2022-01-01)
    Muhammad Razlan Zakaria
    ;
    Nur Aishahatul Syafiqa Khairuddin
    ;
    Mohd Firdaus Omar
    ;
    Akil H.M.
    ;
    Othman M.B.H.
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Shayfull Zamree Abd. Rahim
    ;
    Sam Sung Ting
    ;
    Azida Azmi
    Herein, the effects of multi-walled carbon nanotubes (CNTs) on the mechanical and dielectric performance of hybrid carbon nanotube-woven glass fiber (GF) reinforced epoxy laminated composited are investigated. CNTs are deposited on woven GF surface using an electrospray deposition method which is rarely reported in the past. The woven GF deposited with CNT and without deposited with CNT are used to produce epoxy laminated composites using a vacuum assisted resin transfer moulding. The tensile, flexural, dielectric constant and dielectric loss properties of the epoxy laminated composites were then characterized. The results confirm that the mechanical and dielectric properties of the woven glass fiber reinforced epoxy laminated composited increases with the addition of CNTs. Field emission scanning electron microscope is used to examine the post damage analysis for all tested specimens. Based on this finding, it can be prominently identified some new and significant information of interest to researchers and industrialists working on GF based products.
      1