Puteri S.M. Megat-Yusoff

Effects of Chemical Treatment on Oil Palm Empty Fruit Bunch Reinforced High Density Polyethylene Composites

A 10 wt% oil palm empty fruit bunch (EFB) fiber reinforced high density polyethylene composites were developed and tested for mechanical properties and water absorption. The fibers were treated with various percentages of alkali, acrylic acid and two types of silanes, α-methacryloxypropyltrimethoxysilane (MTS) and vinyltriethoxysilane (VTS). The fibers treated with 10% alkali, 3% MTS, 3% VTS and 5% acrylic acid showed enhanced tensile strength and modulus compared with that of the untreated fibers reinforced composites. The chemical treatments showed approximately 6% and 18% increase in flexural strength and modulus, respectively. The chemical treatments were found to be effective to reduce water absorption of the composites developed. Composites developed from fibers treated with 3% MTS showed highest reduction in water absorption and relatively higher increase in tensile strength and modulus compared to those fibers treated with other types of chemicals and untreated fibers.

Fabrication and Characterization of Cellulose Microfibrils from Pandanus tectorius(Screw Pine) for Polymer Composite Application

Natural cellulose fiber was extracted from Pandanus tectorius (Screw pine) leaves using alkali and combined alkali-bleach treatment. Influence of extraction process parameters on the yield content and mechanical property was evaluated. Optimized process parameter was used in fabrication of a cellulose fiber composite using Vacuum Resin Infusion (VRI) techniques. Chemical composition of screw-pine leaves was determined at different stages of combined alkali-bleach treatment. Structural analysis was carried out by Fourier transform infrared spectroscopy (FTIR). Analysis on morphological structure and tensile strength of the cellulose fiber composite was through scanning electron microscopy (SEM) and universal compressive machine. The results showed that combined alkali-bleach treatment at 4 wt.% of NaClO2 after 8 wt.% of NaOH under alkali treatment resulted in the optimal treatment combination, particularly when soaked for 120 minutes. However, longer soaking time caused damage to the fiber structure. The process parameters all influenced the chemical property, yield content and tensile strength of the cellulose fiber composite. Fiber content of 50 wt.% achieved the maximum tensile strength for the cellulose fiber composite with 28 wt.% composite enhancements for the cellulose fiber composite. The VRI techniques improved the aspect ratio of the cellulose fiber composite after production. The SEM micrograph showed the fibrils of cellulose fiber composite and its deformation. Analysis was carried out to investigate the bonding quality of the cellulose fiber and matrix. As a comparison, a control sample of unfilled epoxy matrix was fabricated

Effects of Halloysite Nanotube Reinforcement in Expandable Graphite Based Intumescent Fire Retardant Coatings Developed Using Hybrid Epoxy Binder System

In this study, the effects of halloysite nanotubes (HNTs) reinforcement in expandable graphite based intumescent fire retardant coatings (IFRCs) developed using a polydimethylsiloxane (PDMS)/phenol BA epoxy system were investigated. Intumescent coating formulations were developed by incorporating different weight percentages of HNTs and PDMS in basic intumescent ingredients (ammonium polyphosphate/melamine/boric acid/expandable graphite, APP/MEL/BA/EG). The performance of intumescent formulations was investigated by furnace fire test, Bunsen burner fire test, field emission electron microscopy (FESEM), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), and Fourier transform infrared analysis (FTIR). The Bunsen burner fire test results indicated that the fire performance of HNTs and PDMS reinforced intumescent formulation has improved due to the development of silicate network over the char residue. Improved expansion in char residue was also noticed in the formulation, SH(3), due to the minimum decomposition of char carbon. FESEM and TEM results validated the development of silicate network over char layer of coating formulations. A considerable mass loss difference was noticed during thermal gravimetric analysis (TGA) of intumescent coating formulations. Reference formulation, SH(0) with no filler, degraded at 300 °C and lost 50% of its total mass but SH(3), due to synergistic effects between PDMS and HNTs, degraded above 400 °C and showed the maximum thermal stability. XRD analysis showed the development of thermally stable compound mulltie, due to the synergism of HNTs and siloxane during intumescent reactions, which enhanced fire performance. FTIR analysis showed the presence of incorporated siloxane and silicates bonds in char residue, which endorsed the toughness of intumescent char layer produced. Moreover, the synergistic effect of HNTs, PDMS, and other basic intumescent ingredients enhanced the polymer cross-linking in binder system and improved fire resistive performance of coatings.

Synergistic effects of mica and wollastonite fillers on thermal performance of intumescent fire retardant coating

In this study, intumescent fire retardant coatings (IFRC) were developed to investigate the synergistic effects of reinforced mica and wollastonite fillers based IFRC towards heat shielding, char expansion, char composition and char morphology. Ammonium poly-phosphate (APP) was used as acid source, expandable graphite (EG) as carbon source, melamine as blowing agent, boric acid as additive and Hardener H-2310 polyamide amine in bisphenol A epoxy resin BE-188(BPA) was used as curing agent. Bunsen burner fire test was used for thermal performance according to UL-94 for 1 h. Field Emission Scanning Electron Microscopy (FESEM) was used to observe char microstructure. X-Ray Diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to analyse char composition. The results showed that addition of clay filler in IFRC enhanced the fire protection performance of intumescent coating. X-Ray Diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) results showed the presence of boron phosphate, silicon phosphate oxide, aluminium borate in the char that improved the thermal performance of intumescent fire retardant coating (IFRC). Resultantly, the presence of these developed compounds enhanced the Integrity of structural steel upto 500°C.