Man-made fibre industry has been showing significantly high rate of growth in recent times. The world fibre consumption ratio of natural to man-made fibres today is about 35 % to 65 %, with nearly all man-made cellulosics and synthetic fibres showing a double digit growth against that of natural fibres. The reason is not far to see. Global population has been growing at an average growth rate of 1.2% over the last decade, and is expected to continue to increase from the current level of 7 billion people to about 9 billion in the year 2050.
The global annual growth in fibre consumption is now 3.4% raising the average per capita fibre consumption to 12 kg. Cotton and other naturals have been the fibre of choice for the warm tropical climate of these countries; but with rapidly depleting availability of land and water resources, and looming food scarcity, their cultivation is increasingly getting restricted. The resultant decline in cotton production globally, shrinking manufacturer margins and sharp rise in cotton prices have pushed man-made fibres to the forefront.
Recycled polyester demands increasing
Clearly man-made fibres are to play an increasingly meaningful role in the textile sector to cater to the future enhanced needs in apparel, household and technical textiles. The challenge will be availability and cost of raw-materials, energy prices and the consciousness related to environment and climate change.
Among the synthetics (polyester, acrylic and nylon), Polyester has been the most important fibre and will remain so in the future. Though there are sufficient raw materials for the polyester industry to last the upcoming decade, the price will be higher and will continue to rise. Because of increasing raw material prices, recycling has emerged as an attractive option recently. Some companies are already using polymers recycled from post-consumer waste, such as PET bottles (which had been used for some kind of consumer product). Recycled polyester, also called rPET, is now accepted as a “sustainable” product in the textile market. The recycling rates in Europe and the USA have been growing rapidly. In Europe, collection rates for bottles is 46% of all PET bottles on the market, while in the US it is 27%. Factories are investing in technology and increasing their capacity. The demand is high, according to a report, beggars in China stand watching people drink so that they can ask for the empty bottles.
Raw material of recycled plastic bottles
Nike is one company that has expanded use of recycled polyester in performance apparel getting a saving on raw materials and reducing energy consumption by an estimated 30% compared to manufacturing with virgin polyester. Nike’s Hyper Elite basketball shorts are made from 100% recycled polyester; while the jersey fabric is made from approximately 96% recycled polyester. The uniforms are made using an average of 22 recycled plastic bottles. Football uniform kits are made using an average of 13 recycled plastic bottles per kit. Approximately 16 million plastic bottles were recycled last year, enough to cover 28 soccer pitches.
Given the increasing demand for fibre, there has been dramatic increase in energy prices and raw material costs. The price of energy has become more volatile than ever in the last 12 months. Increasing from the customary US$10 to US$20 a barrel a few years ago, day-to-day fluctuations in oil prices are hovering between US$60 and US$140 per barrel. According to experts, the era of relatively inexpensive natural resources is over. This situation is unlikely to change in near future as production of raw materials is a very capital-intensive and time-consuming process. Any expansion in capacity of petroleum-based raw materials is unlikely to be solved in a short time.
Cellulosic man-made fibres alternative to cotton
Although marginally sidelined by superior synthetic counterparts, Cellulosic (Viscose, rayon and cupro) man-made fibres have been regaining momentum recently, primarily backed by heightened consumption in Asian countries, improvements in manufacturing processes, plant modernisations, abundant and sustainable raw materials and technological enhancements. Cellulosic man-made fibres by virtue of being moisture absorbent are being looked upon as ideal alternative to cotton. There has also been development of modified cellulosics with premium qualities such as color-fastness, feel, and water retention, aimed at the textiles market and augmenting the demand for viscose fibres. Some recent product innovations in cellulosic fibres and fibre technologies which were presented at last Dornbirn included Tencel Biosoft, TencelWeb and Tencel fibre webs containing activated carbon for use in electrode technology from Lenzing; Umberto speciality fibres, Leonardo speciality fibres, viscose speciality fibres for enhanced fluid management and viscose speciality fibres designed to improve the dispersibility of wet wipes for personal hygiene applications from Kelheim Fibres; a thermoplastic cellulose derivative which can be successfully melt spun into filaments from Toray; inexpensive nanofibres for filter media using supramolecular self-assembly from the University of Bayreuth and RWTH Aachen University; and Supermicro fibres based on cellulose from ITCF Denkendorf.
The fact is that cellulose is one of the most widely used natural polymers, which is easiest to process, particularly in an ecologically sensible manner, based on the technologies available today. Perhaps, some years from now, the cellulose required for the fibre industry will not only be derived from wood, but also from quickly growing plants, such as sugar cane, grass and straw, thus opening up new perspectives. Production of viscose is considered sustainable, as wood from trees is the basic raw material required for 90% of regenerated cellulosic production, and trees have a very low impact on the environment and the fertility of the soil. Moreover, one is far from tapping the full global potential for wood production. According to Austria-based Lenzing AG, the leading producer of viscose fibres, only about 10% of the annual worldwide wood harvest, currently totaling about 1.7 billion metric tons, is processed into pulp. Of this amount, only about 3% is chemical pulp, which is used in the fibre industry and for other applications. In addition, 90% of the renewable land biomass is lignocellulose, which underlines the growth potential.
Bio-synthetics used commercially
Global cellulosic market is being driven by India and China, ranked as two of the largest producers and consumers of cellulosics fibres and its derivatives. Global Cellulosic Man-made Fibre market is projected to reach 5.16 million tons by 2017. In line with the market sentiments, various fibre-manufacturing companies are now beginning to expand their production capacities. New investments are unlikely as the viscose industry is characterized by large technical and capital entry-barriers, which is likely to benefit existing manufacturers.
Many research labs around the globe are busy trying to discover completely new raw materials for the man-made fibre industry. The latest buzz in the man-made fibre space is bio-synthetics. These are fibres created from either 100% natural renewable resources (living organism) or only part of them. Some fibres are already available commercially. PLA (polylactic acid)is polyester derived 100% from corn that was first commercialized as Ingeo from NatureWorks LLC. Known as a hybrid due to its part oil, part renewable content, PTT (polytrimethylene terephthalate) also belongs to the polyester family. Its 37% renewable content is derived from corn and commercial fabrics are branded as Sorona from DuPont. There is also PA11, a bio based nylon derived from castor oil, also known as Rilsan from its polymer supplier Arkema.
Fibres from corn meet challenge
It is understood however that these raw materials will only be able to gain commercial importance and a significant market share in the long-term and there would be many challenges. Take for example the fibres from corn. Corn can easily be used as a raw material for fibre production, but its production puts fibre production in direct competition with the food industry. Also these fibres come with a premium price tag and sometimes they can’t match their mainstream competitors when it comes to a range of performance. The PLA fibres for example have a melting point lower than other synthetics, which in turn put limits on its production and its functionality, like ironing for example.