Sagot :
There are two types of biodegradable materials — natural biodegradable materials and engineered biodegradable materials. Natural biodegradable materials include grass, leaves, and wood. They are the major forms of renewable resources, however they are biodegradable in short periods of time. And they are easily available, which is beneficial for the mass production of products.
Engineered biodegradable materials are based on natural biodegradable materials but contain some modification to make them more effective for industrial applications. Engineered biodegradable materials can be subdivided into two categories: naturally degradable biodegradable materials and synthetically degradable biodegradable materials. Natural degradable biodegradable materials include starch, cellulose, chitosan and polymers. Synthetically degradable biodegradable materials include polylactides and polyglycolides and polyesters. In all cases, these materials can degrade into monomeric carbon dioxide and water when exposed to water and/or certain enzymes.
There are many advantages to using engineered biodegradable materials instead of more conventional products. These include the reduction in our reliance on non-renewable resources, reduction in the need for toxic and persistent substances, reduction in hazardous materials, reduction in the demand for energy and water, and reduction in the emission of carbon dioxide, greenhouse gas.
To make a product to be biodegradable or non-toxic is not enough. Many products like toys, plastic bags, and disposable diapers are now biodegradable and can be disposed of in landfills. Biodegradable and eco-friendly is the future for our environment.
natural biodegradable are the most commonly used in many types of industries. They are easy to get, easy to process, and can be processed rapidly. But they are not as eco-friendly as synthetic biodegradable materials. Synthetic biodegradable materials have the advantage of being more sustainable, more resistant to harsh conditions and more eco-friendly.