Topic of the Month July 2012
The plastics industry is worldwide one of the most innovative sectors. The secret of its success lies in the plastics themselves, which leave almost nothing to be desired – even in view of our society’s globally important tasks. The Topic of the Month in July 2012 takes a closer look at the literally moving aspects of plastics and the special exhibition during next year’s K.
Population growth, increased energy demands, scarcity of resources, climate change – mankind faces challenges of previously unknown dimensions. “This re-quires creative minds and equally creative materials to realize necessary innova-tions”, says Dr. Rüdiger Baunemann. The managing director of PlasticsEurope, the association of plastics manufacturers in Germany, emphasizes that synthetic materials or plastics (polymers) contribute greatly to fulfilling existing and future demands. How mobilizing – both literally and metaphorically – polymer materials can be will be shown in the special exhibition “Plastics Move” during the K 2013.
Can we imagine a world without plastics?
The question seems justified, considering the rapidly evolving plastics industry. Last year, approximately 280 million tons of plastics were produced; in 1950 it was only 1.5 million. Part of this development is the fascinating possibility to turn ideas into real, tangible innovations with the help of plastics. The applications and possibilities are numerous and varied; simply too extensive to be covered fully and in detail in a few lines. Therefore the diversity of plastics and their applications will be demonstrated according to the ‘pars-pro-toto’ principle, by taking a look at a few, but most important areas.
Plastics, the packaging star
One of the biggest areas for the application of synthetic materials is packaging. In Germany, approximately every third ton (34 percent) of plastics is used for the production of packaging materials (Source: PlasticsEurope Germany e. V.). As flexible, tear-proof and intelligent wrapping materials, plastics ensure the safe and efficient transport of food products. Good examples are films made from polyethylene (PE), a material with a good moisture barrier, or from polyamide (PA), which provides a good oxygen barrier. Composite PE/PA-materials can be used to create films of varying thickness for the packaging of foods, which are resistant to water vapor and nearly impervious to air. For example, spices wrapped in a PE/PA film retain their aroma and do not form clumps.
Another excellent example for the use of plastics as packaging materials is the polyethylene (PET) bottle. In 2010, approximately 10 billion liters of mineral and healing waters were bottled in German mineral water facilities; the average per-capita consumption was at around 131 liters mineral water per year. The biggest advantage of the PET bottle in comparison to the conventional glass bottle is its significantly lower weight – a fact which is not only appreciated by the consumer in the supermarket, who has to transport the purchased crate of water bottles from the checkout to the trunk of his car and to the storage room in his house. A PET bottle weighs around 37 grams, a glass bottle around 600 grams; in other words: 16 PET bottles weigh approximately as much as one glass bottle of the same volume. The low weight of the PET bottle presents a significant economical as well as ecological advantage: because PET bottles are so light, the cargo hold of a truck can be fully used without overloading the vehicle, and fewer vehicles on the road means less environmental pollution from car exhaust. With a per capita consumption of 131 liters of mineral water, a consumer would have to transport around 80 kilograms of empty glass bottles per year, while the same number of PET bottles only weighs 4.85 kilograms. Clear advantage for plastics.
Synthetics as ideal insulation material
An uninsulated single-family house, built in the 1960s, loses up to two thirds of its heating energy through external walls, cellar and roof. Every year, approxi-mately 2000 liters of heating oil are wasted this way. In order to prevent the heat loss and reduce the energy demand, houses need a solid coat of modern insulating materials. The most important fully synthetic material in heat insulation is foamed polystyrene. Most widely used is expanded polystyrene rigid foam (EPS), which can be formed into blocks, boards, and other geometrical shapes. Extruded polystyrene rigid foam (XPS) can be produced as a continuous string of foam in varying dimensions (also see Topic of the Month February 2011: “Comfort is key – synthetics as cold weather protection”). All in all, polymer foams sustainably contribute to the insulation of buildings, to the advantage not only of the consumer, but also of the environment. In comparison: The consumption of heating oil in a conventionally built house is approximately 19 liters per square meter (2470 liters/year), the consumption of a house with synthetic insulation only 5.5 liters (585 liters /year). A reduction of 1900 liters of heating oil translates into savings of 1600 Euros and a reduction of greenhouse gases like carbon dioxide of more than 75 percent; instead of 7700 kilograms of carbon dioxide, only 1800 kilograms are emitted (Source: PlasticsEurope).
Transporting drinking water and waste water through plastics safely and without losses
Around eight percent of the German drinking water seeps into the ground un-used, which approximately equals a billion liters per day. Across Europe, the rate of loss is even higher with approximately 25 percent. A similar situation can be found for waste water: approximately a third of the waste water system shows faults and defects. Drinking water pipes usually consist of different materials, such as plastics, metals and composite materials. Aside from steel, underground pipes also use polyethylene pipes (PE-pipes) or pipes made from polyvinyl chloride (PVC). For installations in the house, pipes are predominantly made of copper, stainless steel, galvanized steel (threaded tube), aluminum-multilayer composite and other plastics (PE, PVC-U). Plastic pipes are increasingly used because of their quick and simple installation. The repair of (often aging-related) damages on underground pipes and sewers nowadays mostly utilizes repair methods that do not require digging and therefore avoid damage to streets and sidewalks. Different methods are available, such as the insertion of partial liners or flexible pipe or tube strands. The common factor is the insertion of a synthetic tube impregnated with synthetic resin (epoxy resin or polyurethane resin) or a flexible tube made of polyethylene or polypropylene into the damaged pipe and the leaks are sealed.
Puryfing water safely with synthetic materials
Besides the transport of water, synthetics also play a large role in the treatment and purification of drinking water. A major problem is the availability of clean drinking water. Currently clean water is in short supply for approximately 1.1 bil-lion people. According to the United Nations (UN), 6000 people die every day, around two million people each year, because the hygiene is not appropriate and there is no access to clean, safe drinking water. Part of the problem is ‘home made’, the logical consequence of human existence: waste water. 2.4 billion people do not know what to do with their waste water. It is introduced into the environment without any treatment and purification and finds its way maybe into a lower-level drinking water reservoir in the area. According to calculations, one liter of waste water can pollute eight liters of fresh water. Not surprisingly the main sufferers in this issue are people in the developing nations. But how can this problem be managed? Perhaps by decentralized solutions directly at the location of water withdrawal. The Swiss company Vestergaard Frandsen has developed a mobile, easily transportable water treatment unit, which apparently points in the right direction.
For their new, portable water purificantion system Lifestraw® Family the company Vestergaard Fransen utilizes Ultrason E 6020 P, a polyether sulfon (PESU) created by BASF. The easy-to-operate plastic construction LifeStraw® Family is used to purify large amounts of waste water on location in the villages and families into drinking water. Central element is a plastic casing, approximately 30 centimeters in length, which contains filtering membranes made from Ultrason E. These achieve ultrafiltration (UF-membranes) and remove viruses as well as bacteria from dirty surface waters from rivers, lakes, rainwater collection barrels or even puddles. The special advantage of the high-performance synthetic material Ultrason E in these filters is that it can be processed extremely well into membranes with precisely adjustable pore sizes and therefore clearly defined filter characteristics. The mobile purification station drastically reduces the danger of diseases that are transmitted via dirty water, such as gastro-intestinal diseases. According to the World Health Organization (WHO), every year 1.8 million people die of the consequences of diarrhea.
Efficiently mobile in the future with plastics
The characteristics of plastics – being extremely flexible, highly resilient and yet very light – have boosted the career of plastics in many areas of application. Re-ducing weight in vehicles of all kinds also means savings in terms of cost, use of resources and emissions. It is not about rivaling conventional materials like met-als, explains Dr. Baumann, but about “combining the best of different material worlds”.
For years, plastics-based composite materials have been experiencing a boost in the car industry. Storage compartment lid, hood, sliding roof, brakes, attenuator, tie rod, hub cap, heating tubes, seat belts, driving belt, air filter, valve lid, ignition distributor cap, spark plug connector, connector strips, airbag, headrests, seat covers – approximately 2000 vehicle parts in body, chassis, motor electrics or interior features are today made from plastics or are based on plastics and the trend continues to increase. There are good reasons for this, as the following three examples show. Better functionality: an intake manifold made from synthetic material increases the efficiency of the motor by optimizing the flow properties. Fuel tanks made from plastics can be designed according to individual requirements, which not only reduces the weight of the vehicle, but the available room is also used efficiently and visually attractively. Mufflers made from synthetic material are approximately 13 kilograms lighter than conventional equivalents and only need 50 percent of their space. The waste gas pressure is reduced by half, which means a reduction of carbon dioxide emissions or an enhancement in horsepower. Brought to the point: savings of 0.2 liters fuel per 100 km, transferred to a German car fleet of 42 million cars, results in total savings of 8.4 million liters fuel per 100 kilometers driven. This makes both drivers and the environment happy.
The aviation industry, too, has learned to appreciate the added value of synthetic materials in terms of cost and fuel reduction. For example, 25% of the Airbus A380 consists of plastics reinforced with carbon-fiber. The result: 15 percent less kerosene consumption. Airplane manufacturer Boeing goes even further: “The amount of synthetic materials of the Boeing 787 Dreamliner is already at 50 percent, which leads to considerably lower emissions of environmentally harmful gases during operation, says Dr. Baunemann.
Green energy needs plastics
Clean, environmentally friendly ways of producing energy also cannot get around polymer materials: “The rotors of wind turbines are made of plastics and synthetic materials are the base of commercial solar systems for energy production,” the managing director reports. Polymers furthermore play a central role in fuel cell technology.
By the way: even though the majority of all synthetic materials is still produced from crude oil and natural gas, renewable raw materials are increasingly utilized. Dr. Baunemann:”Fossil resources are simply too limited for the plastics industry to solely rely on them.” However, without plastics, says Dr. Rüdiger Baunemann, the future is not possible: “This is the material of the 21st century.”