4 research outputs found
Effect of the silane coupling agent on the hybrid thermoplastic natural rubber composites filled rice husk and oil palm empty fruit bunch
The used of lignocellulosic material as replacement in composites is currently generating much interest in most application. Lignocellulosic-derived fillers have many
advantages compared to inorganic fillers. The advantages of natural filler receiving increasing attention for industrial application due to cost effectiveness,low density, high specific strength, bio-degradability and free from health hazard
Mechanical characterization of unsaturated polyester composite filled modified kenaf fiber / Suzana Ratim, Rahmah Mohamed and Siti Norasmah Surip
Lignecellulosic fibers such as jute, ramie, kenaf, coir have attracted consideration as alternative materials to replace synthetic fiber and other conventional reinforcements. These natural fiber composite combine good mechanical properties with low specific mass ad offer alternative materials for glass fiber reinforced plastics in some technical application (Gassan 2002). Despite the attractiveness of natural fiber reinforced polymer matrix composites, they suffer from lower modulus, lower strength and relatively poor moisture resistance compared to synthetic fiber reinforced composites (Thwe and Liao, 2002). One difficulty that has prevented the use of natural fibers is the lack of good adhesion with polymeric matrices (Bessadok et al. 2008). According to Gassan 2002, their high level of moisture absorption, poor wettability by non-polar plastic and insufficient adhesion between untreated fibers and polymer matrix lead to debonding with age. The presence of hydroxyl and other polar groups in natural fiber, moisture uptake can lead to weak interfacial bonding between the fibers and hydrophobic polymer matrices (Thwe and Liao, 2002). In particular, the great moisture sorption of natural fibres adversely affects adhesion with hydrophobic matrix leading to premature ageing by degradation and loss of strength reactions (Bessadok et al. 2008). Previous study shown that degradation of mechanical properties caused by higher moisture uptake of natural fiber (Karmaker 1997). Interfacial adhesion and resistance to moisture absorption of natural-fibre composites can be improved by treating these fibres with suitable chemical reactions (Bessadok et al. 2008). It is necessary to enhance the hydrophobisity of natural fiber by chemical treatments with suitable coupling agents or coating with appropriate resin to develop better mechanical properties and environmental performance (Thwe and Liao, 2002)
Synthesis of ZnO nanostructures using sol-gel method
Zinc oxide plays an important role in current industry due to its special characteristics such as anti-corrosion, anti-bacteria, has low electrons conductivity and excellent heat resistance. Therefore, the objective of this study is to synthesize zinc oxide nanostructures with the most practical ways by using sol-gel method and characterize the nanostructures. Sol-gel method is the simplest method and has the ability to control the particle size and morphology through systematic monitoring of reaction parameters. ZnO nanoparticles were synthesized via sol gel method using Zinc acetate dehydrate (Zn(CH3COO)2.2H2O) as a precursor and ethanol (CH2COOH) was used as solvent, Sodium hydroxide (NaOH) and distilled water were used as medium. ZnO nanoparticles were characterized by using XRD, EDX, FESEM, and nano-particles analyser. Result of EDX characterization shows that the ZnO nanoparticles has good purity with (Zinc content of- 55.38% and; Oxygen content of- 44.62%). XRD result spectrum displays mainly oxygen and zinc peaks, which indicate the crystallinity in nature as exhibited. FESEM micrographs shows that synthesized ZnO have a rod-like structure. The obtained ZnO nanoparticles are homogenous and consistent in size which corresponds to the XRD result that exhibit good crystallinity. ZnO nanoparticles were successfully synthesized by sol-gel method in nanosize range within 81.28 nm to 84.98 nm
Green biosynthesis of silver nanoparticles using ‘Polygonum hydropiper’ and study its catalytic degradation of methylene blue
The green synthesis of silver nanoparticles with the small size and high stability paved the way to improve and protect the environment by decreasing the use of toxic chemicals and eliminating biological risks in biomedical applications. Plant mediated synthesis of silver nanoparticles is gaining more importance owing its simplicity, rapid rate of synthesis of nanoparticles and eco-friendliness. In this study, focus on biosynthesis of silver nanoparticles using Polygonum hydropiper extract and its catalytic degradation of hazardous dye, methylene blue has been highlighted. The rapid reduction of silver (Ag) ions was monitored using UV-Visible spectrophotometer and showed formation of silver nanoparticles within less than one hour with maximum absorption of silver nanoparticles at 430 nm. The major functional groups present in the synthesis responsible for the formation of silver nanoparticles. It was identified by using Fourier Transform Infrared spectrophotometer (FTIR). Field Electron Scanning Microscope (FESEM) was used to characterise the nanoparticles synthesized using P.hydropiper. The morphology of silver nanoparticles was predominantly spherical and aggregated into irregular structure with average diameter of 60 nm. In addition, this report emphasizes the effect of the silver nanoparticles on the degradation rate of hazardous dyes by sodium borohydride (NaBH4). The efficiency of silver nanoparticles as a promising candidate for the catalysis of organic dyes by NaBH4 through the electron transfer process is established in the present study