Science 101 Dec 2013 | Página 7

only used hardened clay and glass to store substances, but they were hard and could be broken easily. However, rubber wasn’t efficient for storage, as they get sticky when they are heated and couldn’t retain back i t s FACT every year over 1 million earthquakes shake the Earth shape. Until in 1839, Charles Goodyear accidently discovered a process that could cool the rubber after being heated by the reaction of sulfur with crude oil. This reaction shows that the sulfur forms chemical bonds between adjacent rubber polymer strands .These bonds cross link polymer strands allowing them to retain back its shape, which is known as “vulcanization” ,which made rubber more durable prevent it from bring sticky. In 1846, Charles Schonbein, a Swiss chemist, discovered accidentally that reaction of nitric acid with sulfuric acid on cotton will produce a new polymer. This polymer is nitrocellulose that burst into a smokeless flame, as it was used by the military in place of gunpowder. Then in1870, John Hyat discovered cellulose by the reaction of nitrocellulose and with champor. It was used in billiard balls and photographic films. tion of phenol and formaldehyde. This invention is known as”phenolic resins”, as it led to a class of plastic with similar properties. In other words, Bakelite is hard, resistant to heat and electricity and it doesn’t melt quickly. It was used for jewelry, phones and auto parts, as it could be molded when hot and solidified into hard plastics. In 1930, plastic was known as nylon by a chemist called Wallace Carruthers, who invented the polymer made from condensation of adipic acid and a certain type of diaminohexane monomers that could be drawn out into strong fibers, like silk. Nylon was used in the basis of our clothing and luggage, as it is lightweight and durable. Plastic is one the material that we use everything without realizing, and it totally facilities our lives. For instance, polystyrene is used in food packing to keep food fresh, and plastic made up 10% of all new vehicles materials, which is part of our transportation. Also, Silicon plastic is used in hospitals to achieve high standard of hygiene and it could be used in the production of artificial hearts. In addition, it is used in stopping energy from escaping our home, as silicone sealant around plastic double glazed windows. In 1909, the truly synthetic polymer”Bakelite” was synthesized by a chemist called Leo Baekeland by the reac6