What are the types of degradable mechanics? How do they work?

Question

Another Qns
1) How are plastics wastes recycled?
2) What are the limitations(or long term impacts) of these degradable plastics?

Answer 1

Research as been done on biodegradable plastics that break down with the exposure to snlight. Starch can be mixed with plastic to allow it to degrade more easily, but it still doesn't lead to the complete breakdown of the plastic, unfortunately. Researchers have even genetically engineered a bacteria that will synthesize a completely biodegradable plastic, however this material is very expensive at the moment.

Q: How are plastics recycled?

Thermoplastics can be remelted and reused. There are certain 'codes' placed on the plastics to help sort them out during the recycling process. You've probably seen them on various bottles, too. The link below lists the sort of labels you may find on plastics.
http://en.wikipedia.org/wiki/Plastic#Biodegradable_Plastics

Q: What are the long term impacts of these degradable plastics?

The disadvantage of biodegradable plastics is that the carbon that is locked inside them is released as a greenhouse gas, carbon dioxide, when they degrade. These plastics are also too costly and limited to use at the moment. When such plastic materials are dumped into landfills, they can become "mummified" and persist for decades even if they are supposed to be biodegradable. In this regard, though, plastics are no worse than food or paper, which also fail to degrade in landfills.

Hope this helps!