History of Polymers
Polymers are as old as humanity ( mankind ), yet as new as last century. Indeed, natural polymers and bio-polymers existed before human history.
Early POLYMER History
Natural polymers were obtained from insects, animals, plants, nature. Natural polymers were used for FOOD, CLOTHES, CONSTRUCTION [shelter] and for making TOOLS. Polymers were also ( unknown to the people at that time ) an essential partof LIFE itself. These we call bio-polymers. Natural Polymers include:
| Horn | animal protein |
| Caoutchouc | natural rubber, from the latex of trees |
| Gutta Percha, Balata | natural thermoplastic from the latex of trees |
| Shellac | resin extrudate from insect |
| Amber | the ancient resin of trees |
| Cellulose | papyrus, straw, wood (polysaccharide, straight chain for structure) |
| Proteins | [casein] meat |
| Starch, Glycogen | polysaccharide for energy storage [carbohydrate: rice, potatoe] |
| Wool | protein (polypeptide) |
| Cotton | cellulose (polysaccharide, straight chain for structure) |
| Silk | protein (polypeptide) |
| Jute | natural fibers |
| Hemp | natural fibers |
| Flax | natural fibers |
| Sisal | natural fibers |
| Bitumen | naturally-occuring viscous hydrocarbons: pitch, tar |
| Elaterite | naturally-occuring branched PE |
Cellulose is the most abundant polymer on earth.
Bio-polymers are polymers that we find in organic life. DNA is a very large polymer that contains the entire genetic formula for an organism in one polymer molecule. Proteins are polypeptides ( polyamides ). Human bodies make about 100,000 defferent proteins, that are used as enzymes, hormones, structure ( muscle, hair, hair, skin ).
Life as we know it is simply not possible without polymers. Almost all the 3.5 trillion cells in your body contain billions of DNA building blocks (monomers).
Modified natural polymers
natural polymers were modified to make useful polymer materials. Cellulose Nitro-Cellulose + camphor to make ivory substite for billiard balls Cellulose derivative to make fiber ( rayon, viscose ) or film ( cellophane ) Natural Rubber Rubber solutions applied to cloth ( Charles Macintosh ) Rubber ‘mastication’ process: to make it processble ( Thomas Hancock ) Vulcanization ( crosslinking with heat and sulphur ) Charles Goodyear Highly-crosslinked rubber: Ebonite
Rise of the Macromolecular concept
Although polymer molecules had been used practically for thousands of years, and natural polymers were being modified for new uses and applications, their molecular structure and nature was only discovered recently. Originally, polymers were thought to be a special arrangement of matter, called colloids, with a special kind of bonding. The pioneering work of Hermann Staudinger, only about 80 years ago, showed that polymers were macromolecules – large molecules – with exactly the same covalent bonding as small molecules. Wallace Carothers, working at DuPont Laboratories, used simple chemical reactions between small moleculees to synthesize (nylon and polyester) polymers, thereby proving that polymers are indeed large molecules, made by ordinary chemical reactions and having ordinary covalent bonds
Synthetic Polymers
The first commercial synthetic polymer was a phenol-formaldehyde resin called Bakelite®, developed by Leo Baekeland, in 1910. In the last 100 years, numerous commecially useful polymers have been discovered, invented or developed. Polystyrene was first synthesised in 1839 by a German pharmacist Eduard Simon. Dr. Waldo Semon at B F Goodrich developed PVC in 1926. Polyethylene was accidentally discovered at ICI in 1935 by Eric Fawcett & Reginald Gibson. Roy Plunkett at DuPont accidentally discovered Teflon®. PET was developed at the Calico Printers Association in 1941 by Rex Whinfield & James Dickson. HDPE and PP were developed in the 1950′s by many groups, attributed to Robert Banks & Paul Hogan of Phillips Petroleum. Stephanie Kwolek at DuPont developed Kevlar®.
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