Pictures of the Future Fall 2007
Materials for the Environment – Facts and Forecasts
The World Turns to Renewables
Alongside food production, the production of renewable raw materials has always been one of the agricultural and forestry sector’s tasks. Examples include starch-bearing plants such as potatoes and wheat for paper, cardboard and adhesives; corn and sugar cane for ethanol production; rape for biodiesel; and flax, hemp and jute as natural fibers. Many natural products are direct competitors of petroleum-based products. Against a background of increasing and increasingly volatile prices for petroleum, interest in renewable raw materials is growing substantially.
The hemp industry, for example, is expanding globally. Hemp fibers can be used to reinforce plastics in window frames and floor coverings. Fiber-reinforced plastics have high stiffness and strength, which make them ideal for lightweight engineering. In comparison to glass-fiber reinforced plastics, which due to their high corrosion resistance and good insulating properties are mainly used in electrotechnical products, plastics reinforced with natural fibers can save up to 40 % in weight.
They are also better insulators and hardly splinter when broken. That’s why they are used in passenger car interiors—in interior door panels and trunk upholstery, for example. On average, a middle or upper range car contains 3.5 kg of flax or hemp fibers. But other sectors too, are interested in plastics reinforced with natural fibers. Areas of application range from office chairs and briefcases to cladding for large-scale medical equipment (Renewable Materials).
The International Energy Agency (IEA) is currently forecasting a threefold increase in global demand for bioethenol—for use in engines and petrochemicals, as well as in the cosmetics and beverage industries—from the current 40 billion to 120 billion liters per year by 2020. The world’s biggest supplier is Brazil, which intends to expand its bioethanol production from sugar cane from currently 17 billion to 35 billion liters per year by 2013. In Europe and the U.S., biofuels are increasingly being blended into vehicle fuels in order to reduce dependence on petroleum and increase environmental compatibility. This boosts demand for biodiesel from rape and for ethanol from sugar cane or corn—which, in turn, pushes up corn prices in the U.S. and Mexico. The number of facilities producing ethanol from maize in the U.S. has tripled since 2000 and is increasing further. In Germany, two million of the total 11 million hectares of arable land are devoted to cultivating renewable raw materials, mostly for biofuels. Around 1,600 l of biodiesel can be obtained from 1 ha of rape.
Renewable raw materials also include bioplastics from starch, sugar, and vegetable oils. These materials are used in the fabrication of short-lived packaging, disposable dishes, and flower pots, as well as in automobile interiors. Thermoplastic starches are the most important such biomaterials, accounting for 80 %. Polylactic acid (PLA), polyhydroxybutyric acid (PHB) and cellulose acetate serve as the basis for biopolymers, for use in packaging, in landscape architecture and in medical technology—as pins for small fractures, for example. Petroleum-based plastics could also be replaced by bioplastics in electronics, for example in equipment housings.
Market experts from European Bioplastics expect growth rates of around 20 % per year for bioplastics for the foreseeable future. Today’s global production is around 500,000 t, and is expected to rise to 900,000 t as early as 2010. Bioplastics’ share of the world plastics market (260 mill. t) is still very small, because bioplastics are usually more expensive than petroleum-based plastics. But market researchers from European Bioplastics are convinced that bioplastics are still at the start of their development and that their technical potential is a long way from being exhausted.
Sylvia Trage
