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Plastic : History & evolution

The word plastic is derived from the Greek word (plastikos) meaning capable of being shaped or molded,Unveiled in 1862 at Great International Exhibition in London, it over-shaded all means of materials that were used before it for industrial & household purposes.

First man-made plastic was created by Alexander Parkes who publicly demonstrated it at the 1862 Great International Exhibition in London. The material called Parkesine was an organic material derived from cellulose that once heated could be molded, and retained its shape when cooled.

 PRE 1700
South American Indians used natural rubber (Isoprene) to create items such as raincoats, shoes, balls, and water containers. They used rubber tree sap and a primitive dip molding process to create most of these items.

Small blocks of natural rubber are sold to erase marks made by lead pencils. The motion used to erase these marks leads to the naming of the material – rubber.

Charles Goodyear develops the vulcanization process which improved on the properties of rubber materials by adding sulphur and heat to the natural rubber. This allowed for increased hardness, chemical resistance and wear resistance in the materials by cross-linking, creating chemical bridges between the molecules of the base material.

Christian Friedrich Schönbein develops cellulose nitrate, guncotton, by wiping up a mixture of sulphuric and nitric acid with his wife’s cotton apron. The apron burst into flames when hung above a hot stove to dry.

Alexander Parks displayed Parkesine at the International Exhibition in London. Parkesine is a Cellulosic material made from Nitric Acid and Cellulose.This is known to be 1st true discovery of plastic.

John W. Hyatt submitted a material he developed as a contest entry. The contest was to find a replacement material for Ivory, due to its high cost. The material, Celluloid, was created by mixing Camphor with pyroxylin, a low nitrogen nitrocellulose material. Mr. Hyatt began the production of plastic materials in the United States.

Casein formaldehyde is discovered by Adolf Spitteler.

Leo Baekeland patented Bakelite, a phenol-formaldehyde resin (phenolic). He began the mass production of items that would replace those made of other materials like metal and wood.
This not only produced items that were lighter, more chemically and electrically resistant, and in many cases stronger than the original item, but also allowed for more experimentation in the design due to the ease of fabrication of the newly developed material. Phenolic was the first fully synthetic resin.

Cellulose Acetate was developed as a safer alternative to the explosive cellulose nitrate.
The most common use of Cellulose Acetate today is in cigarette filters
Plasticized Polyvinyl Chloride (PVC) developed by Waldo Semon

Wallace Carothers at DuPont developed Polychloroprene (Neoprene), Polyester, and Polyamide 6. He also coined the terms addition polymerizationand condensation polymerization.
Polyamide, better known as Nylon is the backbone of plastic materials & real star in plastic industry.
Polyvinyl Acetate, Polystyrene, Polymethylmethacrylate, and Polyurethane developed.

Eric Fawcett and Reginald Gibson polymerized Polyethylene

Polypropylene is produced with Zeigler-Natta metallocene catalyst

Polycarbonate discovered at General Electric by Daniel Fox while trying to develop a wire coating material.

Stephanie Kwolek discovered Liquid Crystal Polymers (LCPs) which led to the development of Aramid fibers (Kevlar)

Development of many high temperature engineering polymers; Polyetherketone, Polyetherimide, Polyethersulphone, etc.

2000 -->
Development and commercialization of biopolymers (Polylactic acid and starch based).Plastics and chemicals used in their production come under attack by many environmental groups.

Types : thermoplastics and thermosetting polymers. Thermoplastics are the plastics that do not undergo chemical change in their composition when heated and can be moulded again and again; examples are polyethylene, polypropylene, polystyrene, polyvinyl chloride and polytetrafluoroethylene (PTFE). Thermosets can melt and take shape once; after they have solidified, they stay solid.

Plastics can also be classified by various physical properties, such as density, tensile strength, glass transition temperature, and resistance to various chemical products.Due to their relatively low cost, ease of manufacture, versatility, and imperviousness to water, plastics are used in an enormous and expanding range of products, from paper clips to spaceships. They have already displaced many traditional materials, such as wood, stone, hornand bone, leather, paper, metal, glass, and ceramic, in most of their former uses.

Plastics differ from other materials largely because of the size of their molecules. Most materials have molecules made up of less than 300 atoms, plastics contain thousands of atoms. We call them Macromolecules.

Some plastics are derived from natural substances such as animals, insects and plants but most are man-made. These are named Synthetic Plastics.
Most synthetic plastics come from crude oil but coal and natural gas is also used.
When crude oil is refined gasses are given off . The gasses are broken down into Monomers. These are chemical substances consisting of a single molecule. Thousands of these are linked together in a process called Polymerisation to form new compounds called Polymers.
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