PLASTICS

What is plastic ?

A PLASTIC MATERIAL IS USUALLY A SEMI-SYNTHETIC SOLID. MONOMERS OF PLASTICS ARE EITHER NATURAL OR SYNTHETIC ORGANIC COMPOUNDS.

In Plastics, the arrangement of the individualunits may be linear or cross linked Linear or lightly cross-linked polymers form a class of plastics called thermoplastics.Heavy cross-linking plastics are called thermosetting plastics.

EFFECTS OF PLASTICS ON ENVIRONMENT Climate change The effect of plastics on global warming is mixed. Plastics are

generally made from petroleum. If the plastic is incinerated, it increases carbon emissions; if it is placed in a landfill, it becomes a carbon sink although biodegradable plastics have caused methane emissions. Due to the lightness of plastic versus glass or metal, plastic may reduce energy consumption.

For example, packaging beverages in PET plastic rather than glass or metal is estimated to save 52% in transportation energy.

Thermoplastic

THERMOPLASTIC IS A POLYMERTHAT TURNS INTO A LIQUIDWHEN HEATED AND FREEZES INTO A VERY GLASSY STATE WHEN COOLED SUFFICIENTLY.

THERMO SET MATERIALS ARE USUALLY LIQUID OR MALLEABLE PRIOR TO CURING AND DESIGNED TO BE MOLDED IN THEIR FINAL FORM

Thermo-setting plastics

Virtually any desired color or shape and many combinations of the properties of hardness, durability, elasticity, and resistance to heat, cold, and acid can be obtained in a plastic

Advantages of using plastic

oThey are corrosion resistance.o They have a Low electrical and thermal conductivityo They can be easily formed into complex shapeso Wide choice of appearance, colors and transparencies.

DISADVANTAGES OF USING PLASTICS

o They have low strengthoLow temperature range (up to 600 oF)o Becomes brittle over timeoSensitive to environment, moisture and chemicalsoHazardous to environment because they are non biodegradable. it is consumed by grazing animals such as cow when littered around.

RECYCLING PLASTIC

Thermoplastics can be remolded and reused, and thermoses plastics can be ground up and used as filler, although the purity of the material tends to degrade with each reuse cycle. There are methods by which plastics can be broken back down to a feedstock state.

The greatest challenge to the recycling of plastics is the difficulty of automating the sorting of plastic wastes, making it labor intensive. Typically, workers sort the plastic by looking at the resin identification code, although common containers like soda

bottles can be sorted from memory. Typically, the caps for PETE bottles are made from a different kind of plastic which is not recyclable, which presents additional problems to the automated sorting process. Other recyclable materials such as metals are easier to process mechanically. However, new processes of mechanical sorting are being developed to increase capacity and efficiency of plastic recycling.

bring your own re-useable shopping bags to the market

don’t buy bottled water – use a re-useable water bottle when you’re on the go, and if you do buy soft drinks, look for glass.

use a re-useable coffee cup – keep cups are great, but there are also ceramic re-useable coffee cups on the market shaped specifically for barista use.

buy in bulk and re-package for lunches and snacks. eg. buy blocks of cheese rather than ‘singles’, large bags of sultanas, chips and biscuits rather than ‘snack packs’

go nude for lunch. many schools now have one day a week that is ‘nude food day’ – make it a nude food day everyday! there are a number of fantastic children’s lunch box options around.

How to minimize the use of plastics?

Footer text here 12July 22, 2012

If you bring a reusable glass bottle or aluminium bottle from home and fill it with tap water(homemade lemonade/ice tea), the environmental impact is close to zero- and you save a lot of money too.