Biodegradable Plastic

Introduction

Plastic is known from long time. In 19^th century Europe and America has invented synthetic plastic. During World War II, Nylon played major role. Since then invention in plastic has done in various part of world. Consumption of plastic during World War II was 1.7 kg per person; in 2007 it was almost 100 Kg per person. Now it is reached to 150 Kg per person.

Plastic has several benefits over metal and paper. Their low energy requirement in production, corrosion resistance, and light weight, durable make them unique. In food packaging, it increases food shelve life without using preservative. Today, synthetic plastic faces problem due to health issues. To run the multibillion dollar business industry is looking for new product called biodegradable plastic.

Biodegradable plastics are plastics that can be decomposed by the action of living organisms, usually microbes, into water, carbon dioxide, and biomass. Bio degradable plastics are set to substitute the current plastic in the packaging, single-use, agricultural, and fishing sectors.

Bio-Degradability of Plastic

All type of plastics undergoes some degradation. This could be either Physico-chemical or Bio degradable. Physico-Chemical process is due to weathering like sunlight, wind, rains or hydrolysis/oxidation. This causes micro plastic.

Physico-Chemical degration type

1.       Oxy-degradable plastic –These are generally fossil carbon derived plastic with mixture of additives.

2.       Photodegradable Plastic –these are sub category of Oxy degradable plastic where oxidation is caused by UV light.

3.       Hydro degradable plastic- these are blend of Petro based plastic with natural plastic like starch.

All these type of plastic causes micro plastic at the end of their life.

Bio-Degradable plastic –

      These are caused by micro-organism like bacteria, fungus. Degradation depends on Humidity, temperature and other natural conditions.

Consumers often confuse biodegradable plastics with bio-based plastics. The bio based plastics are plastics made from biomass, generally related to the use of plants as feedstock. Given their natural origin, one could erroneously assume that these plastics are also biodegradable. However, biodegradability depends on the properties of the plastic at hand, including chemical structure and crystallinity.

Similarly, some petro-based plastics are also biodegradable. Bio-based plastics can be considered green as they are made from renewable resources. At the waste management step, a plastic is termed circular if its components are reused or recycled. In as much as that plants use CO2 for growth and CO2 are emitted in aerobic degradation, bio-based and biodegradable plastics are circular.

Below table will give brief about plastic and its defination.

Plastic	Definition	Example
Bio-based	A plastic made from renewable resources, namely biomass or waste	PEF
Bio-degradable	A plastic that can be assimilated by bacteria and/or fungi to give environmentally friendly products	PHB (bio-based),PBAT (fossil-carbon-based)
Oxo-degradable	A plastic whose degradability is induced by additives that initiate oxidation reactions	Oxo-PP
Hydro-degradable	A plastic whose degradability is induced by the polar groups susceptible to hydrolysis	PolyAcryaloamid

 

With all points considered, while tackling plastic pollution, Bio degradable plastic has very appealing properties. It can solve plastic waste management. Carbon emission can be reduced with use of bio degradable plastic. In todays days, Bio degradable plastic is used predominantly in food packaging.

Below diagram give overall view of plastic degradation.

Advantages of Bio Degradable Plastic.

1.       Consumes less energy for production:- Corn based polymer requires 65 percentage less energy than same plastic from petro based.

2.       Plastic is easy to recycle: - They are non-toxic since no chemical involved.

3.       Reduction in waste production:-They break down easily and can be absorbed in soil.

4.       Lower petroleum consumption: - Petroleum has negative impact on environment.

5.       Reduction in Carbon dioxide-Decomposition does not produce much of CO2.

6.       Easily Broken down: - Biodegradable plastic can easily broke down by microorganism.

Dis-advantage of Bio-Degradable Plastic.

1.       Engineering Problem: - Biodegradable plastics are made from plants such as soybeans and corn. Therefore, there is a risk of contamination as the crops are typically sprayed with pesticides when on the farm and can easily be transferred or included in the end product

2.       Costly Setup:- biodegradable plastic is that there is a need for costly industrial processors and composters

3.       Higher Cost:-20-50% more costly than conventional plastic.

 

Treatment of plastic waste

The three Rs- Recycle, Reuse, and Reduce are the simplest steps which can be followed by each person to do their part. This can save energy and other resources as well. Another step is separate biodegradable from non-biodegradable at home and dispose of them separately.

Application Of Bio degradable plastic

These are mostly used in food packaging, transportation, and single use disposable plastic.

In many applications bio degradable plastic can replace synthetic plastic, but have some challenges.

Many biodegradable plastics are designed to degrade in industrial composting systems.

A 2009 study found that the use of biodegradable plastics was financially viable only in the context of specific regulations which limit the usage of conventional plastics

Plastic items labelled as 'biodegradable', but that only break down into smaller pieces like micro plastics, or into smaller units that are not biodegradable, are not an improvement over conventional plastic