Biodegradation
The biochemical breakdown of the materials is Biodegradation. It is different from Biomineralization, which refers to production of minerals by the living organisms. All kinds of animals are able to form minerals. 6 taxonomic Kingdoms Plantae and Animalia have members that produce minerals.
However, Biodegradation involves the degradation of the material. The degradation can be either aerobic or anaerobic.
Biodegradable Plastics
The plastics that decompose in aerobic and anaerobic environment are called biodegradable plastics. They are of mainly two types, viz. bioplastics, which are plastics whose components are derived from renewable raw materials, or petroleum-based plastics which utilize an additive.
Bioplastics are derived from renewable biomass sources, such as vegetable oil, corn starch, pea starch or microbiota. Some notable examples are given here:
- Plastarch Material (PSM)is a biodegradable, thermoplastic resin composed of starch combined with several other biodegradable materials.
- Cellulose Bioplastics, which are mainly the cellulose esters.
- Polylactic acid (PLA)is a transparent plastic produced from cane sugar or glucose
- PA 11, which is also known as Nylon 11is a biopolymer derived from vegetable oil (mostly castor). However, Nylon 12 is a petroleum-based plastic with similar properties and applications. It is being eclipsed by Nylon 11 due to the increasing value of its non-petroleum origin.
Renewable Polyethylene
Renewable Polyethylene is also known as Biopolyethylene. It is made by Ethanol by dehydration. By Dehydration, the Ethanol becomes Ethylene which gets polymerized to give Renewable Polyethylene. The sources of making this material are sugarcane, sugar beet and even wheat. The product is similar to Naphta or Gas based Polyethylene.