Polymers- Dealing with out waste/other uses of waste Flashcards
What are the uses of poly(phenylethene) or polystyrene?
Its cheap, used in foam packaging and insulation.
What are the uses of poly(propene)?
Used in food packaging, for containers that are dishwasher-safe; as a fibre in carpets;and for making synthetic ropes. It is also used as a material for certain laboratory equipment, due its resistance to chemical attack.
What are the uses of poly(ethene) or polythene?
The most widely-used plastic; used to make grocery bags, shampoo bottles,toys,etc.
Define biodegradable.
Biodegradable material is a material that is broken down naturally in the environment by living organisms.
What is the major reason for the need of plastics to be recycled?
The non-biodegradability of plastic.
- Plastic waste contains many poisonous heavy metal ions.
What is sorting?
Before plastic waste can be processed and converted into new products, it has to be sorted. Optical scanning techniques are used to separate PET bottles from HDPE.
What is reclamation?
Polymers are mechanically chopped into small flakes and then sent to manufacture companies,where waste is turned into new materials by melting the pellets and remoulding them.
How can waste polymers b used as a fuel source?
Burning polymers under controlled conditions produces heat energy, which can be harnessed to make electricity.
What is feedstock recycling?
Processes are being developed to convert polymers into synthesis gas, a mixture of hydrogen an carbon monoxide. Hydrocarbons and synthesis gas can be used as a chemical feedstock for conversion into useful products or as a fuel at oil refineries.
How is PVC recycled?
The recycling of poly(vinyl chloride) is problematic because of its high chlorine content.
Incineration has been used to prevent PVC going into landfill sites
What are bioplastics?
These plastics are derived from renewable raw materials such as starch,maize,cellulose and lactic acid.
Why are bioplastics better than normal plastics?
Bioplastics are manufactured by non-hazardous processes and are kinder to the environment. When disposed of, bioplastics degrade naturally from bacteria in the environment to carbon dioxide and water.
