MPOB Technology No. 24 : Palm-Based Polyols and Polyurethanes
The MPOB Technology series contains technical articles on specific aspects of the compoaition, properties, processing, refining, and end-uses of palm oil. It also covers oil palm technology
In the year 2000, the world consumed about 8.65 million tonnes of polyurethanes (PU) comprising 4.64 million tonnes polyols and 3.81 million tonnes isocyanates. All these raw materials were petrochemical-based. Due to the fast depletion of petroleum, R&D to look into alternative sources for PU raw materials has been on-going. But to date, only the production of polyol based on renewable materials such as oils/fats and starch has been reported. A process to convert palm oil into polyols was developed by the Malaysian Palm Oil Board (MPOB) and InterMed Sdn. Bhd. The process was scaled up to 800 kg batch -1 and the palm-based polyols were used to produce a variety of PU products. Depending on the reagents and process conditions, palm-based polyols with viscosities ranging from 4000 cP to 35 000 cP, hydroxyl values ranging from 110 - 200 mg KOH g-1 , and molecular weights ranging from 4500 to 30 000 were produced. Some of these polyols were similar in properties to petroleum-based while others were very different. The polyols were used to prepare polyurethane foams (PUF) with only water as a blowing agent and their properties evaluated. Based on the special properties exhibited by palm-based PUF, certain niche applications were identified and these include flower foam, ceiling panel and roof insulation. The price of palm-based polyols and PUF are expected to increase with the price of palm oil; however, the price is expected to remain competitive to petroleum-based even when the price of palm oil is RM 2500 t-1 . The world market for PU is expected to grow at about 6% per year with the major growth expected to be in the Asia Pacific region. Thus, the commercialization of palm-based polyols is anticipated to be economically viable.