Science has come a long way in the development of new materials and products. 30 years ago, the world had been deprived of new and fantastic materials that have shaped lifestyles. These new products have an extreme diverse range of new developments. This ranges from what we carry our groceries home in and what we store our vegetables in. The efficiency of our cars and the new ways in which we communicate. All of these new developments are courtesy of new breakthroughs in the developments of new materials such as-
Laminates which overtook timber in building.
Glad wrap or plastic cling film replaced grease proof paper.
PVC pipes replaced outdated earthware pipes.
Carbon fibers can replace plastics and fiberglasses.
Space research programs are largely responsible for the new breakthroughs in materials, which potentially have the ability to absolutely modify and reinvent areas of technology, to which they associate with.
Strong and lightweight materials are called composite materials. They are made from
fibers such as glass and carbon embedded in a polymer mix. This is a strong focus in development in materials in areas such as construction and sporting goods- such as tennis racquets and snowboards and boats. These composite materials are also demanded when high strength ratios to weight are needed e.g.- aircraft s.
Substances that have the ability to conduct electricity without losses due to resistance are called superconductors. When superconductivity was first discovered it was only observed at extremely low temperatures (-250 C)
In the late 1980 ssuperconducting ceramics were able to function at-196 C. Low temperature conductors greatly improve the future for electric motors and computer circuitry. This will decrease running costs of such machines dramatically.
Development of materials has extended past machines and products also, the human body has benefited a great proportion of the new developments of materials also. New materials has enabled replacement of legs, arms, hips and even extremely complicated things such as testicles, optical areas and nerves amongst your brain and spine.
All these new fantastical new materials have been produced thanks to developments in the microscope and other such machines. Microscopes though have allowed scientists to see more detailed structures of materials and therefore have been able to understand the ways in which to improve them, and more importantly learn from previous failures without loss of resources.
Most of these new breakthroughs have been motivated and driven by an ever demanding changing society which insists upon cheaper, more efficient, stronger, durable and better materials to source their styles of living. This pressure for new breakthroughs doesn t ever seem to be weakening so therefore a brighter and better technological future can be expected and insisted upon.
Silicon- It is a name given to any of the many polymeric organic compounds made of silicon and oxygen. Their features are that they have high resistance to cold, heat, water and they do not conduct electricity well at all.
Silicon has many uses in many different industries and business areas.
They are used as a grease, a release agent in bread pans to stop the bread from sticking. Silicon is an advantage here because it does not give off smoke and isn t harmful to the atmosphere. Silicon is also used in rubber molds for the same purposes.
Silicon is also used as a waxing and polishing agent on furniture and cars. Its main advantage to furniture is miles ahead of other compounds. Silicon will not absorb water-based products as in ink, juice or tea, no wear or washing will ever remove the silicon, silicon will not lessen the quality of the fabrics either.
Silicones are non-reactive which means they are good for replacement body parts, as they will not disrupt any chemical function that goes on in your body. Silicon is used as hips, lips, breasts, heart valves and joints.
Because of silicones good uses on furniture, they can also be used as permanent lubrication on clocks, chains and ball bearings.
Silicon is also applied on boats and water related bodies because it will not absorb water. It is mixed with house paints and on tile coats in bathrooms.
Silicones are very practical also because they are in prime applicational ability at a range in between 540 C and -70 C
Composition- bonds between silicone are extremely strong- better than Carbon bonds. This is why they are so resistant to heats and so malleable.
Synthetic materials are materials made from chemicals similar of normal rubbers-soft to touch, smooth and stretchy. But synthetic rubbers are intended for cheaper more efficient substitutes. Chemists use the word elastem for any substance that can stretch several times that of their normal position and still maintain normality. Manufacturers of synthetic rubbers group in two types. General purpose and special purpose.
General purpose rubbers (g.p.r.) – the most common used is styrene -butadiene rubber
which is made of 3 components of butadiene and 1 part of styrene. Styrene is made from tar, coal or petroleum. Butadiene is consisted from petroleum and like styrene must be in liquid form to compound into a synthetic rubber.
Special purpose -Contact to oil, sunlight and some gases are fatal for normal rubbers. Special purpose rubbers are far more resistant to these enemies. S.P.R. also have far greater resistance to heat and coolness. S.P.R are more expensive but are well worth it for their advantages.
Special purpose synthetic rubbers and their properties
butyl rubber-
- withholds air and gases better than natural rubbers.
-resists aging, heat and the effects of acid and does not readily conduct electricity.
-wide use in inner tubes and used in lining of tubeless tires.
-main ingredients is butelyne-gas- and isoprene-liquid-both are by-products of oil refining
CIS-polyurethane rubber-Chemical composition virtually the same as naturally occurring rubbers therefore lessening the need for rubber plantations.
-New catalysts which names have not been released have been developed to form this rubber.
Neoprene rubber-
-resists sunlight, oil, oxygen, petrol and other chemicals.
- primary uses are for petrol hoses and insulation for wire cables
- seals for oil and gas containers.
- Neoprane rubber is made from acetylene gas, which is made by cracking petroleum.
Nitrate rubber-
-has an especially high resistance to petrol, oil grease and solvents.
withstand heat up to 177 C, better than natural and most synthetic rubbers.
-used in petrol hoses, papers, and leather products.
-Acryu lanitrile comes from chemical reaction between propylene, oxygen and ammonia which is the components of Nitrate rubber.
Polycrethans rubber
-resists age, heat and high levels of pressure and stress. Made so tough that it is used for car tyres
-used in large quantities usually for upholstery, foamrubber matresses and insulating materials.
- polyurathane foams range from dense to light, flexible too rigid.
- Ingredients are ethylene, propylene, glycols, adipic acids and diisocynates
Silicone rubber-
-keeps its rubber like qualitiesat much lower and higher temperatures.-90 -360 C
- other rubbers become brittle and useless at such temperatures.
-used in seals gaskets and other parts of jet planes and other types of machinery in temperature extremes
- silicon rubber is made from oxygen , silicon, hydrogen and carbon.
Thermoplastic rubbers-
-combined strength of vacranised rubber with processing abilities of plastics.
- Used in such products as shoe soles, car components and adhesives.
Silicon Si, Elements, Reed library.
I for Inventions- Meredith Hooper
The World books Encyclopedia, volume 16. 1990 USA
The World books Encyclopedia, volume 17. 1900 USA
Encarta 1998 Encyclopedia, Microsoft Corporation USA 1996.
Focus on rubber- Theodore Rowland Entwise
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