Effect of Water Absorption on Flexural Properties of Kenaf/Glass Fibres Reinforced Unsaturated Polyester Hybrid Composites Rod

This study investigates the effect of water absorption on the flexural strength of kenaf/ glass/unsaturated polyester (UPE) hybrid composite solid round rods used for insulating material applications. Three volume fractions of kenaf/glass fibre 20:80 (KGPE20), 30:70 (KGPE30), and 40:60 (KGPE40) with three different fibre arrangement profiles of kenaf fibres were fabricated by using the pultrusion technique and were aimed at studying the effect of kenaf fibres arrangement profile and its content in hybrid composites. The fibre/ resin volume fraction was maintained constant at 60:40. The dispersion morphologies of tested specimens were observed using the scanning electron microscope (SEM). The findings were compared with pure glass fibre-reinforced UPE (control) composite. The water absorption results showed a clear indication of how it influenced the flexural strength of the hybrid and non-hybrid composites. The least affected sample was observed in the 30KGPE composite type, wherein the kenaf fibre was concentrated at the centre of a cross-section of the composite rod. The water absorption reduced the flexural strength by 7%, 40%, 24%, and 38% of glass/UPE (control), 20KGPE, 30KGPE, and 40KGPE composites, respectively. In randomly distributed composite types, the water absorption is directly proportional to the volume fraction of kenaf fibre. At the same time, flexural properties were inversely proportional to the volume fraction of kenaf fibres. Although the influence of water absorption on flexural strength is low, the flexural strength of pultruded hybrid composites was more influenced by the arrangement of kenaf fibre in each composite type than its fibre loading.

Kenaf Fibre Reinforced Cementitious Composites

Increased environmental awareness and the demand for sustainable materials have promoted the use of more renewable and eco-friendly resources like natural fibre as reinforcement in the building industry. Among various types of natural fibres, kenaf has been widely planted in the past few years, however, it hasn’t been extensively used as a construction material. Kenaf bast fibre is a high tensile strength fibre, lightweight and cost-effective, offering a potential alternative for reinforcement in construction applications. To encourage its use, it’s essential to understand how kenaf fibre’s properties affect the performance of cement-based composites. Hence, the effects of KF on the properties of cementitious composites in the fresh and hardened states have been discussed. The current state-of-art of Kenaf Fibre Reinforced Cement Composite (KFRCC) and its different applications are presented for the reader to explore. This review confirmed the improvement of tensile and flexural strengths of cementitious composites with the inclusion of the appropriate content and length of kenaf fibres. However, more studies are necessary to understand the overall impact of kenaf fibres on the compressive strength and durability properties of cementitious composites.

Evaluation of Kenaf/Polyester Fiber Blended Sliver Produced from Carding Machine

Controlling sliver evenness is very important since this parameter can affect the quality of the yarn produced. In kenaf sliver production, kenaf fibres alone could not form a good sliver. Thus, fibres such as polyester are needed to blend with kenaf to improve fibre cohesiveness and form a better sliver. The aim of this study is to identify the optimum ratio of kenaf that can be used for sliver production. The heart of the process for the production of kenaf/polyester slivers is carding. The weight percentage of kenaf used for the kenaf/polyester sliver production was 50%, 60% and 70%. After sliver formation, the waste percentage, diameter and size were determined. The sliver images were analysed under video analyser and captured by digital SLR camera to observe the fibre blending. The research showed that lower percentage of kenaf offered better waste percentage and sliver diameter. Whereas, sliver size showed some decrement with an increment of kenaf fibre percentage. The presence of polyester in the production of kenaf/polyester sliver seems to play an important role to bind the kenaf fibres together.

The Influence of Meteorological Variables on Air Pollutants Improvement using Hibiscus Cannabinus L. Kenaf Filter

Bauxite mining activities has led to serious consequences towards humans and environment in term of water pollution, air pollution and has extensively damaged the ecosystem of aquatic life. This study investigates the performance of Hibiscus Cannabinus L. (Kenaf) fibres in improving air pollutants. The influence of meteorological conditions i.e. temperature and wind speed, as well as the thickness of Kenaf fibre filter on the concentration of PM10, NH3, NO2 , and Cl2 after the Kenaf fiber treatment is established. The bauxite sample was collected near Kuantan Port, Pahang and a prototype was fabricated to test ability of the Kenaf fibres in improving air quality. Wind speed and temperature was modified to be similar as the actual conditions on site. The study found that the Kenaf fibre filter improved the concentration of PM10, NH3, NO2 , and Cl2 efficiently after air treatment. Two layers of Kenaf fiber filter showed better performance in removing air pollutants as compared to one-layer filter. One-layer filter is capable to improve 16% to 43% of PM10, NH3, NO2 , andCl2 concentration, whereas as high as 70% of pollutants can be removed when two-layer filter is utilized. The removal efficiencies of NH3 , NO2 , Cl2 and PM10 (with Kenaf) increased from 33%, 17%, 38% and 75% to 60%, 67%, 73% and 85% respectively when the wind speed increased from 900 rpm to 1200 rpm. In contrast, the percentages of removal decreased when higher temperature was applied. The removal of PM10, NH3, NO2 , andCl2 decreased from 75%, 60%, 69% and 41% to 57%, 50%, 65% and 39% respectively when the temperature was increased from 27 °C to 32 °C.

The Physical and Morphological Properties of Kenaf/ Epoxy Fibres in Coating Treatment Process

Natural fibre is an economical material that often used in various applications due to its low in density, non-abrasiveness in processing and biodegradable. But, its usage in various applications is still limited due to the low in overall properties. The acceptable method to improve the properties of the fibres is by chemical treatment method that is costly, meticulous process and high energy demand. Thus, a new, simple and cost-effective fibre coating treatment method was developed which was able to improve the physical and morphological properties that open a new path for natural based materials to be used in a more robust application. In this study, the physical and morphological properties of various coated Kenaf fibres were analysed to comprehend the cutting behaviour of coated fibres after subjected to the pulverisation process. The Kenaf fibres were individually immersed in 1:4, 1:5 and 1:6 epoxy to acetone coating solutions prior cured, and pulverised consecutively using 5 mm, 1 mm, 0.5 mm and 0.25 mm mesh sizes aperture. The morphological characteristic was analysed using polarised optical and scanning electron microscope. The result showed that 1:6 coating ratio solution able to effectively coat the fibres’ aspect ratio that forming individual coated fibre which in long length pulverised fibres. Moreover, the low viscous 1:6 solution able to penetrate inside fibre structure that supported by density and fibre cross-section analysis compare to the other solutions. In future, this analysis is crucial to give insight on the coated fibres behaviour after subjected to the mechanical means of cutting process that later relates to the reinforcing mechanism in the composite samples.