BIOPOL. Biopol, commonly known as PHA is a member of a family of environmentally friendly performance plastics made from renewable sources. They are biodegradable and can be processed into molded goods which are useful in numerous applications for example water resistant coatings. If we continue to use petroleum to make polymers for plastic etc, we will eventually run out therefore Biopol has been introduced as a replacement polymer for petroleum. Biopol is made from a biological substance which is a microorganism known as Alcaligenes eutrophus.
Properties; Biopol is stable when stored in air and even in humid conditions. The decomposition into carbon dioxide and water will only occur when they expose the polymer to microorganisms found in soil, sewage, river bottoms and other similar environments. Other properties include; * Insoluble in water * Good oxygen permeability * Good ultra violet resistance but poor resistance to acid and bases * Soluble in chloroform and other chlorinated hydrocarbons * Biocompatible and hence is suitable for medical applications * Melting point – 175°C Crystallinity can lie in a range of a few to 70% * Sinks in water * Non-toxic Applications/Uses; There are many potential applications for PHA within the medical and pharmaceutical industries mainly because of their biodegradability. Some of its uses include bone plates and bone plating systems, orthopedic pins, adhesion, bone marrow scaffolds, ocular cell implants etc. A PHA copolymer called PHBV is less stiff and tougher which therefore may be used as packaging material such as bottles and canisters. Development of Biopol;
In the 1980s, the British chemical company, Imperial Chemical Industries (ICI) was developed and created copolyester. It was sold under the name “Biopol” and was distributed in the US where it has been further developed. Biopol is a copolymer of hydroxybutyric and hydroxyvaleric acid which is achieved during the fermentation of sugars from sugar beet in the presence of bacteria that transforms glucose into polymer. Researchers in the industry are working on methods with which transgenic crops will be developed that express PHA synthesis routes from bacteria and so produce PHA as energy storage in their tissues.
Another group of researchers at Micromidas Inc. is working to develop methods of produce PHA from municipal waste water. PHAs are mainly processed via injection, molding, extrusion into films and hollow bodies. In June 2005, a US company (Metabolix Inc. ) received an award for their development and commercialization of a cost-effective method for manufacturing PHAs. Evaluation; Biopol being biodegradable has benefited the society at a much greater level compared to materials made by petroleum.
This is because, Biopol is easier to break down whereas plastic made from petroleum may take hundreds of years. Also, petroleum is non-renewable and therefore will eventually run out so Biopol would be a good replacement as it is made of natural organisms that can continue to reproduce. When Biopol is decomposed into carbon dioxide and water, it is not harmful to the environment which again much better than the decomposition of materials made from polymers that originated as petroleum.