Saturday, January 11. 2020PLASTICS AND THEIR HISTORY Cellophane In 1913, Dr Jacques Edwin Brandenberger invented a wipeable surface by adding a clear, flexible film to cloth. Brandenberger invented cellophane. Now it is widely used for packaging and is a fully flexible, waterproof wrap. Bakelite telephone In 1907, a New York chemist, Leo Bakeland, created a liquid resin which he named Bakelite. This resin could be moulded into any shape and it would not burn, boil or melt when it was set. Bakelite was the first thermosetting plastic which would always keep its shape and form. V Kevlar In a laboratory in 1965, two research scientists created a new fibre. They named it Kevlar. It was strong, light and flexible. Today it is used for sports equipment, bullet-proof vests and for ropes used on the expedition to Mars. Nylon stockings In 1939, nylon stockings were unveiled and were extremely popular with many women during the war years (1939-1945). Nylon replaced animal hair in toothbrushes, and silk in stockings. Velcro In 1957, George de Maestral was so impressed with the way that cocklebars — a type of vegetation — used thousands of tiny hooks to cling to anything, he invented a product, using nylon, that would replicate this natural phenomenon. He called it Velcro. Picture Credit : Google Saturday, January 11. 2020PLASTICS AND THEIR USES
Plastics have so many uses and many also have different names. These names include the brand names, trade names, manufacturers' names and the inventor's name. The unique characteristics of plastics mean that an enormous variety of products can be made, such as hard and flexible sheets, foams and fabrics as well as moulded objects. Plastics are an important part of everyday life. The world is full of plastics. Whether you realize it or not, practically everything you see and use on a daily basis is entirely or partly plastic material. Your television, computer, car, house, refrigerator, and many other essential products utilize plastic materials to make your life easier and more straightforward. However, all plastics are not made alike. Manufacturers utilize a variety of different plastic materials and compounds that each possesses unique properties. 1. Acrylic or Polymethyl Methacrylate (PMMA) Well-known for its use in optical devices and products, acrylic is a transparent thermoplastic used as a lightweight, shatter-resistant alternative to glass. Acrylic is typically used in sheet form create products such as acrylic mirrors and acrylic plexiglass. The transparent plastic can be made colored and fluorescent, abrasion-resistant, bullet-resistant, UV-tolerant, non-glare, anti-static and many more. In addition to being than glass and polycarbonate sheeting acrylic is seventeen times more impact resistant than glass, easier to handle and process, and has endless applications. 2. Polycarbonate (PC) Tough, stable, and transparent, polycarbonate is an excellent engineering plastic that is as clear as glass and two hundred and fifty times stronger. Thirty times stronger than acrylic, clear polycarbonate sheets are also easily worked, molded, and thermo-formed or cold-formed. Although extremely strong and impact-resistant, polycarbonate plastic possesses inherent design flexibility. Unlike glass or acrylic, polycarbonate plastic sheets can be cut or cold-formed on site without pre-forming and fabrication. Polycarbonate plastic is in a wide variety of products including greenhouses, DVDs, sunglasses, police riot gear, and more. 3. Polyethylene (PE) The most common plastic on earth, polyethylene can be manufactured in varying densities. Each different density of polyethylene gives the final plastic unique physical properties. As a result, polyethylene is in a wide variety of products.
This density of polyethylene is ductile and used to make products like shopping bags, plastic bags, clear food containers, disposable packaging, etc.
Possessing more polymer chains and, thus, greater density, MDPE is typically in gas pipes, shrink film, carrier bags, screw closures, and more.
More rigid than both LDPE and MDPE, HDPE plastic sheeting is in products such as plastic bottles, piping for water and sewer, snowboards, boats, and folding chairs.
UHMWPE is not much denser than HDPE. Compared to HDPE, this polyethylene plastic much more abrasion resistant due to the extreme length of its polymer chains. Possessing high density and low friction properties, UHMWPE is in military body armor, hydraulic seals and bearings, biomaterial for hip, knee, and spine implants, and artificial ice skating rinks.
4. Polypropylene (PP) This plastic material is a thermoplastic polymer and the world’s second-most widely produced synthetic plastic. Its widespread use and popularity are undoubted because polypropylene is one of the most flexible thermoplastics on the planet. Although PP is stronger than PE, it still retains flexibility. It will not crack under repeated stress. Durable, flexible, heat resistant, acid resistance, and cheap, polypropylene sheets are used to make laboratory equipment, automotive parts, medical devices, and food containers. Just to name a few. 5. Polyethylene Terephthalate (PETE or PET) The most common thermoplastic resin of the polyester family, PET is the fourth-most produced synthetic plastic. Polyethylene Terephthalate has excellent chemical resistance to organic materials and water and is easily recyclable. It is practically shatterproof and possesses an impressive high strength to weight ratio. This plastic material is in fibers for clothing, containers for foods and liquid, glass fiber for engineering resins, carbon nanotubes, and many other products that we use on a daily basis. 6. Polyvinyl Chloride (PVC) The third-most produced synthetic plastic polymer, PVC can be manufactured to possess rigid or flexible properties. It is well-known for its ability to blend with other materials. For example, expanded PVC sheets are a foamed polyvinyl chloride material that is ideal products like kiosks, store displays, and exhibits. The rigid form of PVC is commonly in construction materials, doors, windows, bottles, non-food packaging, and more. With the addition of plasticizers such as phthalates, the softer and more flexible form of PVC is in plumbing products, electrical cable insulation, clothing, medical tubing, and other similar products. 7. Acrylonitrile-Butadiene-Styrene (ABS) Created by polymerizing styrene and acrylonitrile in the presence of polybutadiene, ABS is robust, flexible, glossy, highly processable, and impact resistant. It can be manufactured in a range of thicknesses from 200 microns to 5mm with a maximum width of 1600mm. With a relatively low manufacturing cost, ABS plastic sheeting is typically used in the automotive and refrigeration industries but is also in products such as boxes, gauges, protective headgear, luggage, and children’s toys. Picture Credit : Google Saturday, January 11. 2020HOW DOES PLASTIC ENVIRONMENT?
Wildlife Plastics can be extremely hazardous to wildlife. Each year, many birds become entangled in plastic drinks can holders. Once the plastic is wrapped around a bird's neck or feet, it is difficult to escape. This causes panic and, ultimately, death. Pollution The Trabant emerged in the 19505 as one of the first cars to be made almost entirely out of plastic. While its benefits included value for money and a vehicle that would not easily rust, it also had its downfalls. The plastic used on this car would not breakdown naturally in the environment and so disposal was difficult. Unfortunately, the Trabant added to the mass waste in landfill sites. Re-using Large water containers like these can be re-used many times. This is far more considerate to the environment than disposing of numerous smaller bottles each time you have a drink. it's also a good idea to donate old computers, compact discs, video tapes, toys and household goods to charity shops for re-use. Alternative sources Plastics are made from natural resources that are not renewable. These resources are rapidly running out. Alternative sources such as soya beans and sugars can be processed into plastic products, saving our valuable non-renewable sources. Picture Credit : Google |
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The first plastic-type material was unveiled by Alexander Parkes at the Great International Exhibition in London in 1862. Parkes claimed that his new material could do anything that rubber was capable of, but at a much lower price. This material could be moulded into thousands of different shapes.
Plastics are derived from natural resources — oil, coal and natural gas. We are using oil so fast that the Earth's supplies may run out within 100 years. If they do, so will plastics. Scientists are investigating new ideas for making plastics by processing plants such as the sweet potato, bamboo and flax. .61 Using organic raw materials to make plastics would be kinder to the environment. Items such as a car would be easier to dispose of. If a car was made of organic raw materials most of the parts would naturally rot. Instead of scrapping it, you may just end up eating it!