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Types of Biodegradable Plastic Bags

Most grocery, clothing and specialty stores use plastic bags. In an effort to help the environment, many people are now bringing reusable bags with them when they go shopping or recycling old plastic bags. Stores are also trying to lessen their impact on the earth by using biodegradable plastic bags. Biodegradable bags are classified by the polymers they are made of.

Biodegradable Polymers
- Biodegradable polymers primarily biodegrade using microorganisms to break down enzymes after the plastic reacts with oxygen. Biodegradable polymers decompose into water, methane, carbon dioxide or inorganic compounds.
Oxo-biodegradable Polymers
- Oxo-biodegradable polymer plastic is made by adding a pro-degrading agent to plastic while it is in the extrusion process. This additive triggers an accelerated oxidative degrading process when the bag is exposed to UV rays or mechanical stress. Once disposed, Oxo-biodegradable polymers will degrade in about 12 months. Oxo-biodegradable plastic has no difference in texture, quality or strength to non-biodegradable plastic.
Photodegradable Polymers
- Photodegradable polymers is made by adding UV-sensitive additives to plastic. Once disposed of, the polymers are broken down photochemically into smaller pieces. The small pieces are further broken down with microbial degradation.
Compostable Polymers
- Compostable polymers work with the composting process to be broken down into total mineralization. Compostable polymers break down quickly using bacteria, algae or fungi into water, methane, carbon dioxide or inorganic biomass.
Water-soluable Polymers
- Water-soluable polymers are designed to break down when in put in contact with water. The polymers only break down at a certain temperature and are fully biodegrade using microorganisms.
Starch-based Polymers
- Starch-based polymers are made primarily of renewable sources. Thermoplastic starch-based polymers contain 90 percent of corn, wheat or potato. Star-polyester blends mix renewable sources with hydrocarbons. Starch-based plastic bags break down in 180 days or less, depending on environmental conditions.

Nature