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30 Haziran 2011 Perşembe

WHAT IS A POLYMER? and knowledge on the history



Polymer, monomer so-called small molecules formed by connectinga large molecule with a covalent bond to each other. Likened toignite the chain of hand in hand with people.

Play an important role in the process of living things of life as well asmany organic polymers, inorganic polymers in nature are also many.In addition, synthetic polymer made ​​of a large number oflaboratories using various methods. This product is manufactured in laboratories producing synthetic polymers now used in manyindustries. As an example, the polymers are most suitable to usPVC (Poly Vinyl Chloride) and PU (poly urethane), in the classes ofthermoplastic polymers. Softer and malleable when heated to temperatures above the vitrification temperature of the standing.The desired shape and harden when cooled. Soften when heated, but again and again, and can be shaped if desired. So many timesand can be shaped. PVC, plastic case at the time committed a stable, dry, and they have a flexible feature.



Some of the important first year of production of polymers:


1930 Styrene-butadiene rubber

1936 Poly (vinyl chloride)
1936 Polychloroprene (neoprene)
1936 Poly (methyl methacrylate)
1936 Poly (vinyl acetate)
1937 Polystyrene
1939 66-Nylon 
1941 Polytetrafluoroethylene
1942 Unsaturated polyesters
1943 Polyethylene, branched
1943 Butyl rubber
1943 6-Nylon 

1943 SILICONES

1944 Poly (ethylene terephthalate)

1947 Epoxies 1948 ABS resins
1955 Polyethylene, linear
1956 Polyoxymethylene 1957 Polypropylene 
1957 Polycarbonate
1964 lonomer resins1965 Polyimides
1970 Thermoplastic Elastomers 
1974 Aromatic polyamides


A BRIEF HISTORY OF polymer chemistry:



 sap of the rubber with the feet of the Indians initially occupies the liquid oxygen in the air and then tied together with the effect of these molecules in some locations. These attachments which can easilybe separated from each other because of the longer molecules, so that the liquid-solid state is reached. But some are specific to thesetimes. This rigid structure may move in and all of the small molecularstructure in motion. Structure can be thought of behaving like afishing net. Therefore, this structure acts as partly solid partly fluid.This substance is called rubber. However, it would diffuse in rubbershoes a day. Despite tying together the molecules of oxygen in the air because the oxygen after a period of time, begin to cut thechains and the building would diffuse at the end of one day.


In 1400 the Chinese made ​​a wax-dipped fabric umbrella, then"Direct Coating" will be named as the first application of the date ofthe transaction. Fabric is coated with a material that is completelydifferent (combined) occurred in the function of the idea of ​​change for the better.


• Today, we use the ancestor of polymers such as PVC and PU in 1839, produced by Goodyear. Goodyear, rubber vulcanized with sulfur, which has produced Libonit'i. In 1849, Charles Goodyearrubber tree juice stings flexible to react with sulfur, a substanceclose to the black solid was obtained. Goodyear, this invention is still in production, but in those years, the concept of polymer been taken yet.


 The second largest group of polymers, plastics, the first productin 1868, by John Wesley Hyatt in the United States cottonselülozunu prepared by the reaction of nitric acid and camphorpolimerdi semi-synthetic. Direct Coating process measuring cylinder was produced in Italyin 1900. 1 In the following years The first model produced the Germans during World War II U-Boat. However, very weak against external influences. Between 1920-1930 the German chemist H. Staudinger, "Macromolecule" hypothesis propounded and provedexperimentally. Here is a revolution in the world after this date,polymer chemistry. 1960's fabric and plastic properties of a structure containing at the same time they began touring. Surface, while the strength ofnatural leather effect fabric provided. During these years the "transfer coating" emerged. Used in those transfers up to 100 º C,strong. The development of artificial skin applications of technology and material knowledge has become today.




POLYMER ECONOMIC AREAS:


 SUİTS:



Perhaps many of us never thought our shoes are made ​​of apolymer. Sometimes the skin is different in different and sometimes the softness of gold. Talking about the skin itself ismade ​​of leather is a natural polymer. Hiking boots made ​​ofpolyurethane, most of the six. PVC is found in some of thestructure. Sometimes they use products made ​​of nylon. Many ofour objects we wear wool, cotton (cellulose), natural or artificial means of polymeric materials derived from polyester,polyacrylonitrile (artificial silk), such as training and use of polymeric products.

Only in our daily lives we use every day at sea, as well as textilesfor use in many products made ​​of polymeric materials. Examples include chloroprene and polyurethane products.


 PACKAGING, PROTECTION AND SOME PRODUCTS:


Today, preservation and transportation of the products have beenused in the packaging area on its own. You can clearly see thesimplest form, if you enter a supermarket. Almost all products arepacked. Polymeric materials used in packaging materials, almost all of them are prepared. We use so many materials in our homes.Some of these materials as nylon, polypropylene, some of them,made ​​of polyester or polyethylene.

Children's water-resistant polyethylene or natural rubber pads are used. But perhaps the most important part of the polyacrylic acidportion of the pad. Able to absorb more water than its own weight.
Hydroxyethylcellulose is located in shampoos. If hair sprays;polivinilprolidondan used.


 PHOTOGRAPHY, EYEWEAR AND LENSES:



Cellulose-nitrate films were made of old photos. Later, this product is easy to replace the burning of cellulose acetate polyester later heleft the place.
Tough and transparent color filters used in photography today made​​of polycarbonate.
Refractive index glass lenses are lighter and more in the location, the polycarbonate lenses are. Contact lenses are used in thepolymethylmethacrylate. Car lights are often Acriats also being prepared.





HOME CONSTRUCTION:


One of the most used building materials in our homes, the basicelement in the tree in cellulose materials. The most important elements of domestic water systems, PVC pipes. Electrical wiringin the house just about anything other than copper wires made ​​ofpolymeric materials. PVC doors and windows of buildings because of the advantages of cheap and large sections of the heat insulationis used. Some cracks or holes in the frequent use silicones toprovide water tightness.

In addition, many polymeric products are used in home decorationand flooring. Made of stain-resistant carpets used in flooring, as well as many politetrafloroetilenden use the type of carpet.
Sometimes contain polyvinyl acetate copolymer ofpolymethylmethacrylate acrylic latex paints.


TRANSPORT:


A modern automobile, tires, rubber fibers, except for flooring andpaint are used about 150 kg of polymer material.

Rapidly reduced by the use of metal for airplanes to be able tosave on fuel. Because polymeric materials are lighter than metals.In the air when they are lighter than metals require less fuel spent.




WE ARE AND HEALTH:



If you are single-celled organisms, multicellular organisms to question what if the basic structure, the basic structure of DNA orRNA that contained the information is basically up to 20 amino acids and connecting them to each other that we see in thephosphate bonds. Though the number of amino acids in an organism is greater. But still, this diversity of living things and the amino acid change in ranking is due to conformation. We alsorepeated his body, we might think that there are molecularstructures. So today, the importance of artefact studies of polymersis also increasing day by day.





Polymers are used in many products, only a portion of which is specified appear nearly every day were discussed. If we look more carefully around us, we can see a lot more than the productsmentioned.

To emphasize the importance of the chemistry of the polymer to saythe last word, perhaps, in the U.S. chemical research of more thanone-third of the budget allocated for research in polymer chemistrymay specify leaving.



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