JEC Group have brought together the international community of composites leaders and executives in our Composites Circle as an unique networking opportunity to meet with both peers and future partners.
Like other natural fibres, kenaf is arousing a growing interest, and not just on the part of stakeholders in the composite industry. As the environment becomes not only a major concern but also a source for development, public authorities far and wide are also getting involved, and many projects are emerging. This article presents a Malaysian initiative.
ABDUL RAHMAN KHAN MANAGING DIRECTOR HARUSMAS AGRO SDN. BHD.
Kenaf (Hibiscus Cannabinus, L.) is an annual fibre crop related to cotton and okra. It is native to Africa, where it has been cultivated for use in ropes and animal consumption for at least 4,000 years.
A tropical plant
This tropical plant thrives best on land with good water-holding capacity and is drought tolerant. Kenaf grows up to a height of 3-4 metres within a period of 120-150 days, and is then ready for harvesting.
The kenaf stem is divided into two separate parts, the bark or bast containing relatively long fibres and the stem containing short fibres, called the core. The ratio of the core to bast is 65:35% of the whole stem weight. Kenaf grows on various types of soil but is best grown during the rainy season for good yields. Yields of kenaf range from 8-12 metric tons of dry stem per hectare. Mechanized operation from seeding to harvesting is required for large-scale cultivation.
Fibre production can be processed through mechanical and water retting (separation) where stems are soaked in ponds. Traditional growers of kenaf are China, Indonesia, Myanmar, Thailand, and the United States of America. The fibres (Fig. 1 & 2) are produced mostly for textiles, gunny sacks and, to a certain extent, paper. New uses for kenaf have recently been developed for different industrial applications. Products range from biocomposites, paper, textiles, cattle feed and absorbing agents.
The crop has begun to attract much attention and interest in the last decade. This can be attributed to the growing concerns of global warming and the rising price of petroleum-based products. Paramount is that kenaf is a renewable and sustainable alternative with a short gestation period of only four months. Considerable research has been conducted, and proven that kenaf is an environmentally friendly plant with the potential to replace materials such as synthetic polymers, glass fibres and timber. For example, it was found to have a high absorption rate for carbon dioxide, which is stored when processed. In paper manufacturing, lesser land, energy and fewer chemicals are required for the process. Kenaf was also found to be the most promising candidate for paper production through a research programme conducted by the United States Department of Agriculture (USDA). The trials were conducted with 500 other plant species. Malaysia is also currently looking into the viability of kenaf paper production.
The exhibitions have provided huge opportunities for Malaysian companies in promoting their products and, most importantly, exploring new technologies and information from leading players.
Processing technology has made great strides since the early years. Kenaf has already been used in commercial applications such as composite boards, automotive panels, insulation mats and geotextiles. Major global corporations such as Toyota Motor Corporation and Panasonic Electric Works have taken the lead in the global kenaf industry. Toyota has developed kenaf fibres for automotive interior applications, and Panasonic, a structural wall board to replace timber-based plywood. The kenaf board is far stronger and lighter than plywood.
An original kenaf project
Harusmas Agro Sdn. Bhd. (HASB) based in Sabah, Malaysia initiated a kenaf project back in the year 2000. First, twelve different kenaf varieties were imported from around the world to conduct cultivation trials on HASB’s farm land. Throughout the trials, the crop showed good adaptability to local conditions. The project was then presented to the Sabah state government. Under the leadership of the Chief Minister YAB Datuk Musa Aman the state government is focussing on diversifying its agriculture industry and the development of the green economy. The project was favourably received when a 2,000-hectare piece of land was allocated to HASB for what was called the “Kenaf Commercial Pilot Project”. Also high on the agenda was the introduction of kenaf to the rural farming community as a means to raise their income. This was done through local demonstrations in rural areas.
A strategic plan is being outlined to ensure efficiency and productivity on the part of the rural farmers.
HASB has carried out extensive research and development and trials. Cultivation and harvesting trials started in 2000, followed by trials on high-protein kenaf forage for dairy cattle. The trials showed that 6-8 week-old kenaf contains approximately 18% crude protein (Fig. 3). The next step involved trials on kenaf biocomposites (Fig. 4) for timber replacement in applications such as floor decking, exterior and interior panels. These trials were conducted in Nanjing, China. Several different compositions of polymers and kenaf fibre blends were produced. Different components of the plant were utilized such as bast, core and whole stem. Various profiles were produced from the trials for light and heavy home exterior decking and wall panelling applications. HASB is looking into the viability of converting its core-stem material into polymer-blended interior panels after the extraction of bast fibres. These products will be promoted as green renewable materials. Currently, HASB and the National Kenaf and Tobacco Board of Malaysia are jointly developing a 5-hectare plot for a kenaf variety test in Kota Marudu Sabah. Another 50 hectares will be developed by the end of 2010 for bast fibre and powdered core production. Cut-to-length fibres and powdered-core fibres with specifications of 1-5 mm are produced. The powdered-core fibres will be processed into pallets for biofuel applications.
An alternative fibre
HASB is currently developing kenaf fibres (Fig. 5) to replace glass fibres in exterior automotive parts such as front and back bumpers (Fig. 6).
The project is aimed at developing an ecofriendly product for the automotive customization and modification segment.
The conventional materials used are glass fibre mats processed by hand lay-up methods. The same method was used to apply kenaf fibres, which were converted into mats through various preparation and treatment steps.
The kenaf mats were then laid up with resin at a ratio of 1 kg kenaf:1 kg resin. The project was jointly developed by HASB with Universiti Malaysia Sabah and is currently supported by the Fibre Bio-Composite Development Centre, FIDEC, under the Malaysian Timber Industry Board.
Malaysia has committed to reduce 40% of its greenhouse gas emission by the year 2020. Malaysia’s carbon emission stood at 187 million metric tons in 2006, or 7.2 metric tons for each Malaysian. Serious steps have been taken to address the issue, and Malaysia is fully committed in achieving this objective. Environment-friendly kenaf has been developed in Malaysia since 1999 and will continue to play a part in fulfilling this commitment. The Prime Minister Dato’ Seri Najib Tun Razak has already launched a Green Technology programme. The world can expect to see Malaysia emerging as a formidable player in the natural-fibre and composite industry in the near future. Major development efforts are underway to position the country as a leading producer of kenaf, along with its by-products. Strong support from the government and an emphasis on driving the economy through innovation and technology as envisionned by the Prime Minister, will ensure the success and sustainability of Malaysia’s kenaf industry.