Introduction :- Before starting this important topic, at first we have to know that what plastic really is, how it is made and the importance or necessity of it in our daily life. So at first, “Plastic” is a non – biodegradable human made element which has entered into our daily needs. The story begins here…Leo Baekeland , a famous scientist was the first inventor of plastic. Leo was worried about to make a non conducter element for electricity. He had been searching for a synthetic substitute for Shellac (another bad conducter of electricity),a natural electrical insulator to meet the needs of rapidly electrifying United States .After a long research and after many failures, at last Leo invented Bakelite, the first fully synthetic plastic, which means , it contained no molecules found in nature. But it was just the beginning, thereafter many other people made more different types of plastic innovative , which became popular with time. From 1960’s , plastics were prepared on a large scale in the United States, United Kingdom , Sweden and in many other countries. And now each and every country even states or districts are producing plastic so that it can satisfy the daily human needs.
Types of plastic :- Plastics are usually classified by their chemical structure, polymer type , side chain , bondings . According to these basis there are normally five different types of plastics, they are :- acrylics , polyesters , silicones , polyurethanes , and halogenated plastics .
On the basis of some other characteristics like their various physical properties , the chemical process used in their synthesis such as – condensation , polyaddition and cross linking; even on it’s hardness , tensile strength , resistance to heat , density , organic processions such as – oxidation , ionizing radiation plastics can be defined into four types : Polyethylene(PE), Polypropylene(PP) , Polystyrene(PS) , and Polyvinyl chloride(PVC) . To summarize we can say that there exists totally seven types of plastics in the modern world and they are :- 1.Polyethylene terephthalate (PET or PETE) 2.High density poly ethylene (HDPE) 3. Low density polyethylene (LDPE) 4. Polyvinyl chloride (PVC) 5. Polypropylene (PP) 6. Polystyrene(PS) 7. Low quality polymers.
How plastic is made :- Plastic can either be “synthetic” otherwise “biobased”. Synthetic plastics are derived from crude oil , natural gas or coal . Whilst bio based plastics are made from renewable products like carbohydrates , vegetable fats , vegetable oils , starch , bacteria and likewise other biological substances. The vast majority of plastic in use today is synthetic because of the ease of the manufacturing methods involved in the processing of crude oil . However the growing demand for limited oil reserves is driving a need for newer plastic made from renewable resources such as waste biomass or animal waste products from the industry.
Most of the plastic in use today is derived from the following steps :
1. Extraction of raw materials:- (largely crude oil and natural gas, but also coal)—these are a complex mixture of thousands of compounds that then need to be processed.
2. Refining process transforms the crude oil into different petroleum products including monomers and various polymers. At first crude oil is heated into a blast furnace, then it is sent to the distillation unit where it separates into lighter components called fractions. One of these components is Naphtha , a crucial compound to make a large amount of plastic .
3. Polymerization is the next and the most important step where light olefin gases such as ethylene , propylene , butylenes (i.e. monomers) are converted into higher molecular weight hydrocarbons (polymers). This happens when monomers are chemically bonded into chains. This process decides that the plastic will be of which kind.
4. Compounding/Processing : In compounding various blends of materials are melt blended to make formulations of plastic. Generally an extruder of some type is used for this purpose which is followed by pelletizing the mixture. Compounding often occurs on a twin screw extruder where the pellets are then processed into plastic objects of unique design , various size, shape, color with accurate properties according to the predetermined conditions set into the processing machine.
Usage of plastic:- Plastic has become a very important need in our whole everyday life. Plastic is where not? From the pipeline of water to the electrical wires, from carry bags to other weighing products , various household materials , insulators , tires , furnitures , combs to shoes…..plastic is everywhere. It provides us cheaper price but higher durability and higher efficiency than most other substitution materials . No big deal , it’s productivity has made us to be highly dependable on plastic. That’s why the modern world has been converted into “The Plastic World”.
The upcoming danger due to the usage of plastic and it’s solution:- The polypacks , plastic materials plastic toys and vase have flooded the market now. They have become an inseparable part of our daily lives. Thinking of any material without plastic has become an utterly impossible idea. But this high and hazardous usage of plastic have thrown us towards a very serious upcoming environmental danger. Plastic materials are handy, portable , durable and cheap. People tend to use them without knowing their seamy sides. At present polythene bags are used at random by the shopkeepers . Paper packets have practically vanished Fruits, sweets, spices, fish, meat and what not are all carried in polythene packets . It is argued that polypacks are comparatively cheap, neat and handy. But we know overuse of anything is bad. Now experience tells us that polypacks are harmful for users. First of all , plastic is not bio friendly. Secondly, medical research reveals that the use of plastic may cause certain respiratory and skin diseases. It is poisoning the environment other than the equally damaging effluents. The chemicals the polypacks are made of are dangerous for the food products. Lastly, polyethylene goods never mix with soil. This hampers fertility of the soil . Over and above, it results in land pollution. Sometimes they are bornt but the problem remains unsolved. After burning it turns into micro components but never destroys. Poisonous gases released therefrom affect the eco balance. Many aquatic or roaming creatures consume them as their food and as a result they are choked to death. This is a danger alarm for the allover biological and environmental balance. Thus the use of polyethylene goods can on no ground be justified.
The governments and the higher officials of all most of the countries has already put a ban on the usage of polyethylene goods (commonly polythene packets) . It is surely a welcome move. But the law is not enough. This problem should be seriously emphasized and dealt with so that we can create general public awareness against the use of harmful plastic made things. We have to return to the various other substitutes of plastic which would not affect the mother nature . Papers, jutes , and some metals can be used as a proper substitute of plastic goods. It would be difficult at first to intentionally exclude plastic from our daily use but it is not impossible. If this natural world converts into a human made “plastic world”, then it will be impossible to survive in this world for any natural being. This is high time to take necessary steps to make this earth a plastic free , greener , safer and happier world. Hope all the well conscious thoughts will arise amongst in the human being to save this world from being cluttered as human being is the only game changer in this play.
