Report by Dr Ho Lim, KPX Chemical Co.Â Ltd, R&D Center, 300-2 Yeocheon-dong, Nam-gu, Ulsan, Korea Paper given at the 2nd international polyurethane forum held in Busan, Korea, 31 May - 1 June 2010, organised by the Korean Polyurethane
Traditionally, the materials used to form polyurethane foams for industrial applications are derived from petrochemical resources such as propylene oxide and ethylene oxide. Using renewable resources as feedstocks for chemical processes will reduce the environmental impact by decreasing the demand for non-renewable fossil fuels currently used in the chemical industry and reduce the overall emission of carbon dioxide, the most notable greenhouse gas. Over the years, natural oil based polyols (NOPs) are getting a lot of attention and have been synthesised utilising biobased material (vegetable oil) such as soyabean, palm and castor oil to replace petroleum feedstock.
In this study, we review the background of NOPs, properties and market of vegetable oils and manufacturing processes of NOPs. Also we show several NOPs, and then go on to describe experimental work at KPX on polyols based on various seed oils. We discuss the physical properties of polyurethane foam made with these NOPs, compared with properties of foams made using conventional polyols. Lastly we consider the present problems and the future of NOPs as a eco-friendly material.
The chemical sector is normally a petroleum based economy, using naphtha cracking to turn crude oil into basic raw materials for developing and making other chemicals. But, as sustainability issues and protecting the environment become more pressing in the global economy, alternatives have gradually been developed.
Global issues which will determine the future of resource uses in polyurethanes and other sectors include the uncertainty of future oil supply. Energy demand is predicted to rise by 20 percent by the year 2020, and oil production is expected to reach a peak some time between 2010 and 2020 and then decline.
Sustainable development necessitates the move towards other sources of materials than crude oil (Figure 1).
These factors, together with the need to limit climate change by cutting greenhouse gas emissions, are pushing all sectors towards developing alternative, renewable sources of raw materials.
In the polyurethanes sector, we can use biomass technology and biochemical processes, including fermentation of sugars and biorefining techniques, to develop bio-products, including biopolyols, or natural-oil-based polyols (NOPs).
The 21st century is seeing a group of âmegatrendsâ that include the rising price of oil as a result of fossil-fuel depletion. This has been accompanied by rising interest in alternative energy sources and a particular focus on renewable forms of energy generation.
Another of the megatrends is the focus on environmental protection, to reduce climate change by cutting CO2 emissions. This can lead to what is called a âBlue Oceanâ market â one where a player may be able to generate business by creating new demand in an uncontested market space.
Biotechnology and bio-refining fall into this category â and may also create new jobs in an industrial economy.
Advantages of naturally based chemicals over petroleum-based products include the fact that they use natural and renewable resources that are theoretically available in abundance. The production system for bio-oils is eco-friendly, as it uses natural resources. Environmental pollution is lowered with such materials as their production gives low emission of greenhouse gases and cuts air pollutants. The method also offers a diversity of energy forms (liquid, gas, electricity, biochemicals, etc).
Against this are ranged some disadvantages, including difficulties in gathering and transporting agricultural resources, and the restricted vegetable resources available in any specific area. The diversity of resources available tends to also result in the need for a wide range of technologies to handle them.
Another drawback is that excessive development of agricultural resources for chemicals and energy may lead to environmental destruction. Also high on the list of negative aspects is the potential that food shortages may result from use of food biomass in this way, if food sources such as corn and soya beans are exploited widely to make chemicals and fuel.
World trends in bioprocesses
In the reports quoted in Table 1, various bodies predict a rise in use of biomaterials in electrical goods in the next five years to 260 kilotonnes, from 100 kt presently. In the same period, these organisations expect use in automotive outlets to rise six-fold to 860 kt, from 140 kt in 2010.
|Table 1 World market trends in bioplastics usage (won, bn)|
|Electrical goods||-||5000 (100kt)||13000 (260kt)|
|Automotive interior materials||-||7000 (140 kt)||43000 (860kt)|
|Commodity (packing material)||3500||20000||46000|
|Total 3500 32 000 99 000||3500||32000||99000|
|Source : IDC (â06), CMAI (â06), BCC Inc. (â05); (I000 Won = $0.86 Sept 2010)|
|Table 2 Trends in biochemical technology|
|DuPont Biomaterials||Sorona fibre||(polytrimethylene terephthalate); 1,3-propanediol (with Genencor)|
|Dow||Biomaterials||Enzyme (Genencor); PLA (Cargill-Dow JV)|
|Cargill||Food/agriculture||PLA (Cargill-Dow JV); 3-HP producing enzyme( with Codexis)|
|BASF||Biocatalysts||Amino acid; Vitamins (with Novozyme); Methoxy isopropyl amine; Styrene oxide|
|Degussa||Fine chemicals||Acrylamide; Fatty acid induced ester; Polyglycerine ester; organic silicone|
|â¢ Source: Report of Korean Ministry of Commerce, Industry and Energy 2007.|
|Table 3 World production of oils and fats (million tonnes)|
|M tonne||%||M tonne||%||M tonnes||%||M tonnes||%|
|World oils and fats||30.78||129.14||165.66||184.8|
|Sources : Malaysian Palm Oil Board (2004). Oil World|
|Table 4 Production costs for raw material for biopolyol by region|
|Table 5 Raw materials for NOPs â harvest area for NOPs â harvest area (M HA)|
|Table 6 Worldwide biopolyol product maker|
|Company||a Brand name||Raw material Use||Capacity||kt/y|
|Urethane Soy Systems||Soyol||Soyabean oil||Flex; rigid||22.68|
|Bio Based Technologies||Agro||Soyabean oil||CASE, Flex, Rigid|
|Intermed Sdn Bhd||Palm oil||Rigid||50|
|Maskimi Polyol Sdn Bhd||Palm oil||Flexible||21.6|
|Laizhoushi Jintian Ind. Co. Ltd||Castor oil||Rigid||12|
|Shanghai Gaowei Shiye||Soyabean oil||7|
|Australia Bioresin Pty Ltd||Rescon||Castor oil Rigid|
|a. First four companies, US, next two, Malaysia, next two, China, last one, Australia|
|Table 7 KPX Biopolyol substitution in PU foam|
|PU foam type||Type of use||Substitution(a)||Status|
|slabstock||Flame lam. Foam||30%||Commercial|
|Flexible||Seat pad foam||10%||Proto finish|
|Moulded||Dash pad foam||10%||Lab. test|
|Rigid||Refrig. Foam||30%||Line trial|
|Table 8 Properties of KPX biopolyols|
|Appearance of liquid||Yellowish||Clear||Yellowish||Clear||Visual|
|Colour, APHA No||120||50||120||50||ASTM D4890|
|Viscosity, cps at 25Â°C||710||460-520||1560||1100-1200||ASTM D4878|
|pH value||6.9||5.5-7.5||6.9||5.5-7.5||pH Meter|
|Acid value, mgKOH/g||0.01||0.1||0.01||0.1 max||ASTM 4890|
|OH value,mgKOH/g||55||53-58||26.8||27-29||ASTM D4274|
|% Water||0.02||0.1 max||0.02||0.1 max||Karl Fisher|
|Table 9 Physical properties of|
|slabstock foam with KPX biopolyol|
|Table 10 Physical properties of|
|flame lamination foam with KPX biopolyol|
|Compression set (70C, 50% def, 22h)||%||34.4||4.7|
|Adhesion Str (b)||Good||Good|
|a) MVSS-302, (b) KPX chemical method|