Mohd Firdaus Omar
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Preferred name
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
    Improving flexural and dielectric properties of carbon fiber epoxy composite laminates reinforced with carbon nanotubes interlayer using electrospray deposition
    ( 2020)
    Muhammad Razlan Zakaria
    ;
    Hazizan Md Akil
    ;
    Mohd Firdaus Omar
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Aslina Anjang Ab Rahman
    ;
    Muhammad Bisyrul Hafi Othman
    The electrospray deposition method was used to deposit carbon nanotubes (CNT) onto the surfaces of woven carbon fiber (CF) to produce woven hybrid carbon fiber–carbon nanotubes (CF–CNT). Extreme high-resolution field emission scanning electron microscopy (XHR-FESEM), X-ray diffraction (XRD), Raman spectroscopy and Fourier transform infrared spectroscopy (FT-IR) were used to analyze the woven hybrid CF–CNT. The results demonstrated that CNT was successfully and homogenously distributed on the woven CF surface. Woven hybrid CF–CNT epoxy composite laminates were then prepared and compared with woven CF epoxy composite laminates in terms of their flexural and dielectric properties. The results indicated that the flexural strength, flexural modulus and dielectric constant of the woven hybrid CF–CNT epoxy composite laminates were improved up to 19, 27 and 25%, respectively, compared with the woven CF epoxy composite laminates.
  • Publication
    Effect of Glass Reinforced Epoxy (GRE) pipe filled with geopolymer materials for piping application: compression properties
    ( 2016)
    Mohammad Firdaus Abu Hashim
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Che Mohd Ruzaidi Ghazali
    ;
    Kamarudin Hussin
    ;
    Mohammed Binhussain
    ;
    Mohd Firdaus Omar
    The aim of this paper is to achieve the highest compressive strength of glass reinforced epoxy pipe with the geopolymer filler content of weight percentage that were used in glass reinforced epoxy pipe. The samples were prepared by using the filament winding method. The effect of weight percentage of geopolymer materials in epoxy hardener was studied under mechanical testing, which is using the compression test. A series of glass reinforced epoxy pipe and glass reinforced epoxy pipe filled with 10 – 40 weight percentage geopolymer filler which is white clay were prepared. The compression strength of the glass reinforced epoxy pipe filled geopolymer materials is determined using Instron Universal Testing under compression mode. It was found that compressive strength for samples with white clay geopolymer filler are much higher compare to glass reinforced epoxy pipe without geopolymer filler. Moreover, the compressive strength of glass reinforced epoxy pipe filled with white clay geopolymer filler was increased from 10 wt% to 30 wt% of geopolymer content. However, the compressive strength of glass reinforced epoxy pipe with white clay geopolymer filler suddenly decreased when added to 40 wt%. The results indicated that the blending of geopolymer materials in epoxy system can be obtained in this study.
  • Publication
    Studies on factors affecting unconfined compressive strength of industrial rubber sludge containing heavy metals treated using ordinary Portland cement via stabilization/solidification technique
    ( 2020-12-18)
    Abdul Latif Abdul Rani
    ;
    Rashid N.A.
    ;
    Muhd Afiq Hizami Abdullah
    ;
    Mohd Firdaus Omar
    ;
    Salim A.S.
    ;
    Anuar N.A.I.
    High concentration of selected heavy metals within industrial rubber sludge collected from rubber industry wastewater treatment plant has classified the waste as scheduled waste. Special treatment to the waste by using ordinary Portland cement via solidification/stabilization (S/S) technique has been performed in laboratory scale. The objective of this research is to determine related factors that affect unconfined compressive strength (UCS) performance of stabilised/solidified (s/s) cube specimens which contains industrial rubber sludge waste. Other parameters observed include the curing condition (i.e. air and water immersion curing method), waste composition, specimen age and density. The prepared fresh mix were cast in plastic moulds in order to produce 50 mm3 cubical shape specimens and leaved to set approximately 24 to 48 hours. The prepared specimen batches are S1 (90% OPC + 10% waste), S2 (70% OPC + 30% waste), S3 (50% OPC + 50% waste). UCS was performed on respective specimen age of 7 and 28 days. Positive results were obtained as relatively the average compressive strength of 7 day air cured specimens reach 5.25 MPa, 5.28 MPa, and 2.16 MPa for S1, S2 and S3.While, 28 days air cured specimens results are 9.59 MPa, 8.01 MPa, and 1.46 MPa for S1, S2, and S3 respectively. As for water immersion, the compressive strengths are 8.19 MPa, 4.93 MPa, and 1.90 MPa for 7 days, and 7.75 MPa, 10.10 MPa, and 2.11 MPa for 28 days at respective S1, S2 and S3 sequence. As conclusion, the specimens prepared passed the minimum requirement for secured landfill disposal which is at 1 MPa.
  • Publication
    Partially Replacement of Cement by Sawdust and Fly Ash in Lightweight Foam Concrete
    ( 2020-03-18)
    Mohd Firdaus Omar
    ;
    Muhd Afiq Hizami Abdullah
    ;
    Rashid N.A.
    ;
    Abdul Latif Abdul Rani
    The rapid growth of population has led to increased demand for fast, affordable and quality housing development. Today, the construction industry in Malaysia has shifted from conventional methods to Industrial Building Systems (IBS). The most commonly used IBS component is precasat concrete with lightweight foam concrete. This study focuses on the main component of foam lighweight concrete, which is a partially replacement of cement by sawdust and fly ash. Among the features of lightweight concrete is density below 1800 kg/m3. Therefore, the objectives of this study is to determine the effects of sawdust and fly ash as part of cement replacement in terms of mechanical properties (compressive strenght) and physical properties (water absorption). In addition, this study also determine the optimum percentage of cement replacement by sawdust and fly ash in building material. The percentage of saw dust and fly ash used in this study as a partial replacement cement are 5%, 10%, 15% and 20%. The results show that increasing the percentage of mix propotion will increase the water absorption rate as well as decrease the compressive strenght of strength. Also, the density and compressive strength of lightweight foam concrete will decrease as the percentage of partial replacement cement increases. According to JKR Standard Specification for Building Works that referred in Malaysia, the minimum compression strength of lightweight foam concrete allowed for hollow blocks is 2.8 N/mm2. The results obtained from this study show lightweight concrete blocks using saw dust and fly ash as part of the cement replacement meet the standards and can be commercialized in the industrial building system development.
  • Publication
    Evaluation on physical and chemical properties of treated industrial wastewater sludge containing latex and heavy metals using ordinary Portland cement via stabilization / solidification technique
    ( 2020-07-09)
    Abdul Latif Abdul Rani
    ;
    Rashid N.A.
    ;
    Muhd Afiq Hizami Abdullah
    ;
    Mohd Firdaus Omar
    Industrial wastewater sludge containing latex collected from rubber industry wastewater treatment plant has classified the waste as scheduled waste due to high concentration of selected heavy metals within it. Laboratory scale of special treatment via solidification/stabilization (S/S) technique has been performed to the waste by using ordinary Portland cement. The objective of this research is to evaluate the chemical properties of the raw waste using X-Ray Fluorescence (XRF) and physical properties related to unconfined compressive strength (UCS) performance of stabilised/solidified (s/s) cube specimens. Other factors took into consideration include the curing condition using air and water immersion curing technique, waste addition percentage, specimen age and density. The fresh mix prepared were cast in plastic moulds internal dimension of 50 mm3 producing cubical shape specimens and cured approximately 24 to 48 hours. The prepared specimen batches are A1 (90% OPC + 10% waste), A2 (70% OPC + 30% waste), A3 (50% OPC + 50% waste). Chemical analyses using XRF indicates that raw sludge contains approximately several heavy metals such as Aluminium (30%), Phosphorus, P (17.5%) and Zinc, Zn (11.7%). UCS testing were conducted on 7 and 28 days of specimen age. Positive average compressive strength results of 7 day air cured specimens reach 5.25 MPa, 5.28 MPa, and 2.16 MPa for A1, A2 and A3. Next, 28 days air cured specimens results are 9.59 MPa, 8.01 MPa, and 1.46 MPa for A1, A2, and A3 respectively. As for water immersion, the compressive strengths are 8.19 MPa, 4.93 MPa, and 1.90 MPa for 7 days, and 7.75 MPa, 10.10 MPa, and 2.11 MPa for 28 days at respective A1, A2 and A3 sequence. Based on the UCS performance, the tested specimens surpassed the minimum requirement for secured landfill disposal which is at 1 MPa.
  • Publication
    Enhancement of tensile properties of glass fibre epoxy laminated composites reinforced with carbon nanotubes interlayer using electrospray deposition
    ( 2021)
    Muhammad Razlan Zakaria
    ;
    Mohd Firdaus Omar
    ;
    Hazizan Md Akil
    ;
    Muhammad Bisyrul Hafi Othman
    ;
    Mohd. Mustafa Al Bakri Abdullah
    The introduction of carbon nanotubes (CNTs) onto glass fibre (GF) to create a hierarchical structure of epoxy laminated composites has attracted considerable interest due to their merits in improving performance and multifunctionality. Field emission scanning electron microscopy (FESEM) was used to analyze the woven hybrid GF-CNT. The results demonstrated that CNT was successfully deposited on the woven GF surface. Woven hybrid GF-CNT epoxy laminated composites were then prepared and compared with woven GF epoxy laminated composites in terms of their tensile properties. The results indicated that the tensile strength and tensile modulus of the woven hybrid GF-CNT epoxy laminated composites were improved by up to 9% and 8%, respectively compared to the woven hybrid GF epoxy laminated composites.
  • 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
    Micromechanical modeling of polyamide 11 nanocomposites properties using composite theories
    ( 2023)
    Khairul Anwar Abdul Halim
    ;
    James E. Kennedy
    ;
    Mohd Arif Anuar Mohd Salleh
    ;
    Azlin Fazlina Osman
    ;
    Mohd Firdaus Omar
    ;
    N.M. Sunar
    The use of organically modified clays as nano-reinforcement in polymer matrices is widely investigated owing to their remarkable reinforcement at low filler loading. In this body of work, the nanocomposites were prepared by melt blending nanoclay with polyamide 11 (PA 11) utilising a twin-screw extruder in order to maximise the dispersion of clay particles within the matrix during compounding. The main aim of the work was to study the reinforcing effect of nanoclay within PA 11 using two micromechanical model namely Halpin-Tsai and Mori-Tanaka composite theories. These theories were used to predict the effective tensile modulus of PA 11 nanocomposites and the results were compared to the experimental data. In addition, the Halpin-Tsai model was used to predict the storage modulus and heat distortion temperature (HDT) of PA 11 nanocomposites. It was found that the tensile modulus for nanocomposites with a high clay aspect ratio exhibits up to 10% higher when compared to the nanocomposites with lower clay aspect ratio. Thus, it is believed that the combination of clay aspect ratio and modulus contributes to the super reinforcing effect of nanoclay within the PA 11 matrix.
      4  8
  • Publication
    Thermal properties of nanocellulose-reinforced composites: A review
    ( 2020-03-15)
    Gan P.G.
    ;
    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. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48544.
      1
  • Publication
    Preliminary investigation on the correlation between mechanical properties and conductivity of low-density polyethylene/carbon black (LDPE/CB) conductive polymer composite (CPC)
    ( 2022-01-24)
    Farah Badrul
    ;
    Khairul Anwar Abdul Halim
    ;
    Salleh M.A.A.M.
    ;
    Mohd Firdaus Omar
    ;
    Azlin Fazlina Zakaria
    ;
    Muhamad N.A.
    ;
    Muhammad Salihin Zakaria
    The insulating nature of a polymer can be changed to electrically conductive by incorporating conductive fillers within the polymer matrix to form a conductive polymer composite (CPC). One of the potential application of CPCs are in the area of flexible electronic interconnect application. Nevertheless, the correlation between the electrical conductivity and mechanical properties of CPCs such as tensile was found to be limited. Therefore, this paper is aimed to report the preliminary investigation on the correlation between conductivity and mechanical properties of a low-density polyethylene (LDPE) incorporation with conductive filler which is carbon black (CB. It was observed that the tensile strength was decreased by up to 29.4% and the elongation of break was decreased by up to 90.6% at higher CB loading compared to pure LDPE. Nonetheless, the modulus of elasticity and the electrical conductivity of the composites were increased by up to 150.5% and 16.4% at higher CB loading respectively. Moreover, it was found that the effect of CB additions on the tensile modulus was greater compared to the conductivity of the CPCs.
      1