We can say the present world economy is largely based on petrochemicals. Untill the beginning of the 19 the century global economy was largely based on carbohydrates. With the emergence of petroleum and its diverse set of products, world shifted progressively from carbohydrates to hydrocarbons.
Hydrocarbons are responsible for most of the present day pollution. Further petroleum reserves are gradually diminishing and one day they will be no more. The diiping reserves may even cause a raise in the price. There is thus a need to shift focus on alternatives to petroleum and its products.
Alternative forms of energy like wind, solar, and wave energy serve as alternatives to petroleum for fuel. Experts project that wind power will cader 20% of total electricity needs of America by 2030. Many efforts are in place to harness the wind, solar and wave energy across the globe.
Unlike the Petroleum based fuels, these are clean forms of energy and generate no pollution. Green house gas emmisiions can be reduced by increasing the share of these alternative forms of energy in the global energy usage. One day they might be the only option left behind. So its better we start workin on them seriously right from now.
Its not just in the area of fuel that we got to look into alternatives for petroleum. Many polymers are petroleum derivatives. About 7% of the petroleum reserves are used for polymer production. This can be replaced by Bio-Polymers. Biopolymers are obtained from raw materials produced by plants and animals or microbes. Unlike the hydrocarbon based polymers they are readily degradable under composting conditions (You should remember that normal conditions are not compostinditions. Special composting facilities are necessary. Hydrocarbon based polymers donot degrade under composting conditions).
Ofcorse there sre still many hurdles in the use of these alternatives.
Solar energy is very expensive at present.
Wind energy can be harnessed only in locations where sufficent wind speeds are available. Also proper infrastructure has to develop.
Coming to biopolymers they are not as efficient as synthetic polymers. The are either fragile, opaque, less tensile etc. So they can't be applied for the diverse apllications served by the synthetic polymers.
Efforts are in place and we will have the results in the years to come. Wish this happens at the earliest.
Biopolymers:
Biopolymers are obtained from natural sources like plants, microbes and animals. Plant biomass (carbohydrate) is a major source for the production of biopolymers. Countries like India and China that have abundant agricultural waste have a huge potential for the production of Biopolymers from plant biomass. (Crop residue in India is about 2 billion tonns). Its not wise to divert food material for the production of Biopolymers.
At present the share of biopolymers in the global polymer industry is 0.5% and is expected to grow to around 1.5 to 5%.
Yes, biopolymers are more environmental friendly. But to what extent are they good enough to replace the synthetic polymers. Certin properties of biopolymers act as barriers. Some biopolymers are brittle, some are thermally unstable, some are oaque. Example: PHB and PLA are extremely brittle. Combinations of various polymers can help in improving the properties.
(PHB: Poly Hydroxy Butyricacid. PLA: Poly Lactic Acid)
Apart from the above mentioned properties, some other market barriers include:
- Price
- Inadequate facilities for composting.
- Packaging films.
- Drug delivery Systems
- Foams
- Blends and composites
- Integrated Bio-refinery
