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The Raw Material Shift by Dipl.-Phys. Michael Carus, nova-Institut

The terms “raw material shift” and “energy shift” mean the transition of the raw material and energy supply from fossil to renewable resources. While the term “energy shift” has been deep-seated for years, the term “raw material shift” is still quite new.

Demand for renewable resources is rising

For almost two years, scientists at nova-Institut Germany have been noticing new dynamics in the raw material market. The demand for renewable resources is rising and driven by economics for the first time – and not by ecology and the desire for rural employment, as was the case up to now. The high oil price is starting to deeply change the raw material supply structure. The raw material shift is unstoppable and we are already right in the middle of it. Hundreds, if not thousands, of product lines are already being converted from mineral oil to renewable resources, Figure 1. After agricultural raw materials as a raw material base for industry lost market shares to

mineral oil-based raw materials for decades, a trend can now be observed due to the high oil and plastics prices. Agricultural raw materials – cellulose, starch, sugar, vegetable oils, natural fibres and natural rubber — are regaining lost market shares. This applies to both traditional applications and new techniques such as biotechnology or new composites, which have massively advanced since the first oil crisis in the 1970s. The raw material shift is still retarded by the heavy subsidisation of the energy shift. The artificially stimulated demand in the energy sector currently increases the price of many agricultural raw materials, with the result that they are often still too expensive for

the working material sector. In the mid to long term, however, the use of renewable resources will become considerably more important, as there are hardly any alternatives to them. Will there be enough agricultural land worldwide to supply the raw materials required? The energy and raw material shift will lead to a shortage of land and crops and to fierce competition for cultivation areas. This can – and will – result in substantial socio-economic problems on a regional level. Even today, there is resistance in the Asian population to new palm oil plantations. The regional population becomes the loser in the large-scale utilisation of renewable resources by finan-

27 components of the S-Class are made of renewable raw materials.

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Figure 1: Door trim beam made of flax in the BMW 3 Series.

cially sound companies – not to mention the destruction of rainforests. Bringing about the raw material shift in a socio-ecologically friendly way constitutes a challenge. Otherwise, our grandchildren might prefer a return to the ecological and beneficial mineral oil age! Without a doubt, the shortage of agricultural land will lead to high agricultural raw material prices. The era of cheap raw materials will inevitably be over – regardless of whether it is based on the decreasing mineral oil supply or based on renewable resources. In the field of industrial materials, numerous new developments and market launches have been made in recent years, Figure 2.

Comeback of Jute Sacks All over the world, but especially in Asia and North Africa, woven jute sacks have a long tradition of serving as packaging for commodities such as rice, sugar or coffee. In recent decades, these have been increasingly replaced by woven polypropylene (PP) sacks, mainly for price reasons. Even in 2002, jute sacks were still three times as expensive as woven PP sacks. According to FAO 2005, the price relation between sacks made of jute fibres and PP has since shifted more and more in favour of jute. Currently, prices are approximately the same and jute sacks are able to regain lost market shares. Because of the increasing demand for jute, jute fibres have naturally also become more

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expensive. However, this is unproblematic from the point of view of the raw material shift, as long as jute fibre prices increase more slowly than plastics prices. In recent months, this has not always been the case, but it can be expected for the future.

Comeback of Natural Rubber The development of the market shares of natural rubber over the past three years is an extreme example of the raw material shift. The production of natural rubber has never been as high as today, but nevertheless cannot meet the demand. While less than seven million tons were produced in 2000, production will already be more than nine million tons this year. An even faster increase in production is prevented by the fact that the establishment of new plantations takes six to seven years until the first harvest comes in, and additionally is in land competition with palm oil plantations used for energy production. After decades of decline, the market share of natural rubber has rapidly increased in recent years. While the share was previously only about 30 %, it is now once again more than 42 %, equalling the level of 1964. The worldwide tyre industry, the main buyer of rubber, raised the use of natural rubber from 39 to 42 % in 2005 – and would have liked to further increase this share if enough natural rubber had been available on the market.

The synthetic alternatives such as styrene butadiene rubber and polyisoprene suffer from high oil prices and limited capacities that, due to competition from natural rubber, are not currently being expanded. The considerable shift in demand has initiated a price spiral. After synthetic rubber had been cheaper for decades, the price of natural rubber was merely about 85 % of synthetic rubber at the end of 2005. After the present price increases for natural rubber, the two are now approximately on the same level. Within only 18 months, the price for natural rubber has almost doubled!

Era of cheap raw materials will inevitably be over

Car Seats Made of Coir with Natural Latex Car seats made of coir fibre with natural latex have been in standard use for a long time, but were then superseded by cheap PUR foams and survived only as a high-quality niche product in some luxury cars. Now they are returning thanks to increased process automation and the high oil price. FaserTec, Figure 3, has reached the price level of foam. Due to the continuous price increase and the shortage of crude oil which, as the basic material for the production of PUR, has an influence on the price of foam cushions, FaserTec products might become even cheaper than foam cushions one day [1]. As with traditional rubberised fibre products, the production of FaserTec starts with coir and la-

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tool is completely filled, it closes to form the final geometry of the cushion.

Renewable Raw Materials in Automotive Production

Figure 2: Headrests made of coconut fibre for DaimlerChrysler commercial vehicles.

In the field of work materials, numerous developments have been made

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tex. Johnson Controls procures these raw materials from countries such as India, Sri Lanka, Cameroon, Malaysia, Thailand, China and South America. Under the old procedure, the coconut fibres are spun into long threads and wound onto reels. Then, the coir is mechanically twisted against the direction it was spun and formed into a continuous non-woven sheet, which is then sprayed on both sides with liquid latex and dried. The latex bonds the fibres together and provides a degree of strength to the matting. Next, the material is punched out and placed by hand into compression moulding machines. The final steps include vulcanising, stamping and sanding, as well as assembling the components, if the car maker so desires. Cushions can be made significantly more quickly and more efficiently with a new procedure called FaserTec Direct Application. The method combines several fabrication steps into one, using robots. Most importantly, this avoids the cost-intensive moving and stamping of the coir matting. The FaserTec facility consists of eight round tables, each equipped with five tools. On each table, a robot applies the fibre-latex mixture from a special nozzle in precisely defined strokes onto the tool, which has been fitted with a non-woven material made of recycled wool wadding. The fibrelatex mixture is then moulded into the proper shape by the respective mould stamp. When the

BMW’s involvement in use of renewable raw materials in automotive production began in the early 1990s with projects to investigate the use of plant fibres, Figure 4. At that time, the Bavarian Ministry of Agriculture and a flax management specialist were integrated into a pilot project undertaken by BMW together with a partner company and a manufacturer of nonwoven fabrics. The background to this work lay in the European Union policy of curbing the surplus production of foodstuffs. In return for appropriate compensation, growers within the Community were required to set aside a certain percentage of their land used for arable crops. In order to address the question of cultivation, however, they were permitted to use this land for the production of renewable raw materials. These efforts to promote the production of renewable materials have paid off. Whereas industry was previously compelled to import the requisite fibres such as flax from abroad, a substantial proportion can now be supplied by the domestic agricultural sector.

Natural Fibre and Wood Fibre Reinforced Plastics In the field of work materials, numerous developments have been made in recent years and market introductions have taken place. Examples are bioplastics made from starch, sugar and cellulose, natural fibre and wood fibre-reinforced plastics. These new working materials and composites will particularly benefit from the raw material shift. The following chart gives an overview of the use of natural fibres – bast fibres including coirs, wood fibres and reprocessed cotton — in composites in German passenger car and truck production. While the use of bast fibres has been steadily increasing for seven years, the use of wood fibres and wood flour has decreased in parallel, as has the use of reprocessed cotton, although to a lesser degree. Table 1 shows that, regarding the total amount of natural fibres, approximately 89,000 tons of natural fibres were used in about 145,000 tons of composites in German passenger car production in 2005. Reprocessed cotton composites have a fibre content of approximately 71 %, consisting of 80 % reprocessed cotton, 5-10 % wool and 10-15 % other fibres. The reprocessed cotton content is therefore approximately 57 %.

Figure 3: Producing cushions on FaserTec round tables. AutoTechnology 1/2007

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An analysis from November 2006 by nova-Institut shows that the use of natural fibre-reinforced plastics has further increased, although with lower growth rates than in previous years. While more than 99 % of natural fibre and wood fibre-reinforced plastic working materials were processed in compression moulding processes in 2003, since then new processes such as natural fibre press flow-moulding and PP-NF injection moulding have been able to gain ground. They reached a market share of 5 % in 2005. But the natural fibre compression moulding technique is also steadily advancing and is still an interesting option for several automotive interior parts from a technical and economic point of view. This particularly applies to construction parts with an annual production quantity of less than 100,000 units, because compression moulding tools are considerably cheaper and more flexible than injection moulding tools. The first automotive natural fibre exterior parts were manufactured in natural fibre flow-moulding presses, and are currently being used in the underbody of the Aand B-Class from DaimlerChrysler. Abaca fibres from Philippine production are used as natural fibres for this purpose. Several, mostly small and medium-sized companies from the Netherlands, Germany and France are today offering PP-NF granulates on the market, several thou-

Figure 4: Assembly of the door trim in the BMW 3 Series.

sand tons of which were used in 2006. For example, in Germany a flap disc made from PP-NF instead of PP-FG (fibre glass) is produced and marketed – meanwhile accounting for more than 500,000 parts. It is expected that, over the next years, there will be substantial growth in the PP-NF injection moulding sector. At present, unusually low glass fibre prices, due to dumping prices from China, are retarding the market success. However, since glass fibres are ten to twenty times more dependent on the energy price than natural fibres, the market success of natural fibres in the injection moulding sector should be unstoppable on the long term. While petroleum-based matrices (PP, PE and PVC) are still dominant today in the field of

Use of natural fibres in tons

natural fibre-reinforced plastics and wood plastic composites (WPC), a trend towards the use of bioplastics can now already be observed, primarily for PLA, which is produced from sugar and starch. In Japan, NEC has proven that this is already possible today. In 2006, a mobile phone was introduced to the market with a body consisting of kenaf fibre-reinforced PLA. What are still PP and glass fibres today, could be PLA and natural fibres tomorrow. PLA still costs three times as much as PP, but production costs already equal to PP are expected in the case of mass production.

While petroleumbased matrices are still dominant

[1] Klusmeier, W., Technische Textilien 1/2006.

Natural fibre

Main applications

Average content of natural fibres in the composite

Natural fibre composites in tons

Natural fibres (plant fibres except cotton and wood)

Interior of mediumclass and luxury class passenger cars

19,000 (2005)

approx. 40 %

approx. 30,000 (2005)

Wood fibres and wood flour composites

Interior of passenger cars and lorries

approx. 25,000 (2003)

approx. 70 %

approx. 36,000 (2003)

Reprocessed cotton (recycling)

Interior of passenger cars and particularly lorry driver`s cabs

approx. 45,000 (2003)

approx. 71 % and 57 % resp.*

approx. 79,000 (2003)

Total (all vegetable natural fibres)

Passenger cars & lorries

approx. 89,000

-

approx. 145,000

Table 1: Natural fibre composites in German automotive production in 2003/2005. AutoTechnology 1/2007

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