Plastic is the general common term for a wide range of synthetic or semi synthetic organic amorphous solid materials used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce costs.
The word is derived from the Greek πλαστικός (plastikos) meaning fit for molding, and πλαστός (plastos) meaning molded. It refers to their malleability, or plasticity during manufacture, that allows them to be cast, pressed, or extruded into a variety of shapes—such as films, fibers, plates, tubes, bottles, boxes, and much more.
The common word plastic should not be confused with the technical adjective plastic, which is applied to any material which undergoes a permanent change of shape (plastic deformation) when strained beyond a certain point. Aluminum, for instance, is plastic in this sense, but not a plastic in the common sense; in contrast, in their finished forms, some plastics will break before deforming and therefore are not plastic in the technical sense.
There are two types of plastics: thermoplastics and thermosetting polymers. Thermoplastics will soften and melt if enough heat is applied; examples are polyethylene, polystyrene, polyvinyl chloride and polytetrafluoroethylene (PTFE). Thermo sets can melt and take shape once; after they have solidified, they stay solid.
For the past few years, there has been rising international awareness regarding the damaging and dangerous impact on the environment of plastic bags. Governments all over the world have decided to get involved in that particular issue. Some governments have decided to ban them: Bangladesh, Bhutan and Zanzibar. Plastic bags should no more be given for free in China from June 1st. These bags are surcharged in Germany, South Africa, Ireland and Israel. Several countries try and promote, through major retailers, the use of cloth bags, paper bags or grocery bags: United Kingdom (with Tesco), France (with Carrefour), and New Zealand.
The thing is, the raw material of plastic bags is oil. Therefore, the more we use plastic bags, the more we waste oil - a non-renewable energy source. The petroleum-based plastic bags take decades to break down, so if they are not recycled they litter. It creates visual pollution: in the streets, on the beaches etc. Also, they can clog roadside drains, which could cause street flooding during heavy rainfall. Plastic bags can be recycled but it rarely happens: according to the United States Environmental Protection Agency, only 1% of plastic bags were recycled in 2000, against twenty percent for paper bags. They endanger wildlife and particularly sea life such as sea turtles and dolphins which can die of entanglement, suffocation, and ingestion because they assume that these bags are jellyfish.
Bisphenol A, a common chemical used to make certain plastics has been linked to potentially deadly diseases like diabetes, heart disease, and cancer. Studies have shown that 90% of American people have Bisphenol A in their bodies. Exposure to Bisphenol comes from many different sources such as the foods we eat, the water and beverages we drink, electronics, and even our dentists Even babies come in contact with Bisphenol at an early age, as many baby bottles are made from the plastic.
When San Francisco became the first U.S. city to prohibit large grocery stores and pharmacies from distributing disposable plastic bags in March 2007, it appeared to have sparked a trend. At least a dozen other cities, counties and states were soon considering proposals to ban or severely restrict distribution of what many environmentalists consider a wasteful and harmful product.
The plastics industry had no intention of allowing the San Francisco model to spread without a fight, though. It quickly and quietly joined with retailers and other business interests and launched a successful counterattack, using lobbying muscle to quash proposed bans. In the face of the onslaught, the cities have instituted voluntary recycling programs that proponents of the bans say are ineffective and likely to remain so. And in at least two instances, plastics interests have turned the tables on their green adversaries by filing lawsuits on environmental grounds in an effort to prevent bans from taking effect.
Plastic materials display properties that are unique when compared to other materials and have contributed greatly to quality of our everyday life. Plastics, properly applied, will perform functions at a cost that other materials cannot match. Many natural plastics exist, such as shellac, rubber, asphalt, and cellulose; however, it is man's ability to synthetically create a broad range of materials demonstrating various useful properties that have so enhanced our lives. Plastics are used in our clothing, housing, automobiles, aircraft, packaging, electronics, signs, recreation items, and medical implants to name but a few of their many applications.
The synthetic plastic industry started in 1909 with the development of a phenol formaldehyde plastic (Bakelite) by Dr. L. H. Baekeland. The phenolic materials are, even today, important engineering plastics. The development of additional materials continued and the industry really began to blossom in the late 1930's. The chemistry for nylons, urethanes, and fluorocarbon plastics were developed; the production of cellulose acetate, melamine, and styrene molding compounds began; and production of commercial equipment to perform the molding and vacuum forming processes began.
Acrylic sheet was widely used in aircraft windows and canopies during World War II. A transparent polyester resin (CR-39), vinylidene chloride film (Saran), polyethylene, and silicone resins were also developed. The first polyethylene bottles and cellulose acetate toothpaste tubes were manufactured during this time period.
The post war era saw the production of vinyl resins started, the use of vinyl films, molded automotive acrylic taillights and back-lighted signs introduced, and the first etched circuit boards developed. The injection molding process entered commercial production. Due to the newness of the materials, the properties and behavior of the plastic materials were not well understood. Many products were introduced that failed, creating a negative impression about plastics in the public's mind.
Chemists continued the development of materials, such as ABS, acetyls, polyvinyl fluoride, ionomers, and polycarbonate. The injection molding, thermoforming, extrusion, transfer molding, and casting processes were all improved. This allowed the industry to provide an even greater number of cost-effective products suitable for many, more demanding engineering applications.
In the early days, Bakelite (phenolic resin) is most often actually a product called Catalin. Both, along with Plaskon, are formaldehyde based plastics. Allow me to expand (with liberal borrowing from Dr. Stephen Z. Fadem - a true expert). Around the turn of the century, the Belgian born scientist Dr. Leo Baekeland, working as an independent chemist, came upon the compound quite by accident. He sold his rights to Velox to Eastman Kodak for three quarters of a million dollars and started developing a less flammable bowling alley floor shellac; bowling was becoming the latest rage in New York City. Dr. Baekeland soon realized that a resin that was both insoluble and infusible could have a much wider appeal when used as a molding compound. He obtained a patent and started the Bakelite Corporation around 1910.
Phenolic resin could be produced in a multitude of colors, commonly yellow, brown, butterscotch, green and red. Omitting the pigment could produce a transparent or translucent effect. The resin could be molded or cast, depending on variations in the formula. For molding, the formula was cooked until resinous, spread out in thin sheets to harden, then ground to a fine consistency. At this point, powdered fillers and pigment were added, to enable the resin to be molded and to add color. This mixture was then put through hot rollers which created large sheets of colored, hardened resin. These sheets were then ground into a very fine powder which was molded under high heat and pressure into the final product form. As a molded material the resin's drawback was the limited range of colors which could be created. For casting, the formula was modified slightly, enabling the resin to be poured into lead molds and then cured in ovens until it polymerized into a hard substance. The liquid resin could be tinted to any color or "marbleized" by mixing two colors together.
For the first ten years or so after its introduction, the resin was used primarily to make electrical and automobile insulators and heavy industrial products. Eventually, uses for the resin spread into the consumer market. Castings were made in the shape of cylinders or blocks, and then sold to novelty and jewelry makers. Industrial designers began experimenting with the new material. Fine craftsmen sculpted the molded products on fast wheels with razor-like tools to carve out designs that the world has not seen since; after World War II, most companies switched to creating designs through the use of patterned molds, instead of hand-carving. Bakelite replaced flammable celluloid, previously the most popular synthetic material for molded items, as a major substance for jewelry production.
The process to the collector of today may not be significant, as Bakelite is now treasured for its unique, irreproducible beauty. A deeply carved half inch bangle bracelet may sell for $225.00, and a two and one half inch bangle may command $900.00. Bakelite often acquires a patina within a few months to a few years of its date of production, and metamorphosizes into a completely different appearing color. The red, white and blue Bakelite designs of yesterday have mellowed into lovely yellows, reds and blacks, enhancing further the value of those rare pieces which have continued to maintain their original color and luster.
Bakelite's many uses allowed it to become a standard item in the family home of the 1930s and 1940s. It was frequently found in the kitchen, in the form of flatware handles, rabbit or chicken napkin holders, salt and pepper shakers, or serving trays. During the Depression Bakelite sold more than any other commercial product, and was loved by the public for its brilliant and cheerful colors and its affordability.
When the Bakelite patent expired in 1927, it was acquired by the Catalin Corporation that same year. They began mass production under the name "Catalin," using the cast resin formula which enabled Catalin to add 15 new colors to the original five produced by the Bakelite Corporation, which used the limited color range molded formula, as well as the now-famous marbleized effect. One of their most notable products was the Fada bullet radio. The Catalin Corporation was responsible for nearly 70% of all phenolic resins that exist today.
Bakelite-Catalin was sold mostly by Saks Fifth Avenue, B. Altman and Bonwit Teller, but was also on the shelves of F.W. Woolworth and Sears. To the wealthy socialites, whose husbands had fallen on tough times during the Depression, with Tiffany diamonds and Cartier jewelry now well beyond their means, the vibrantly colorful carved jewelry adorned with rhinestones became de rigueur for cocktail parties and formal dinners. Yet, Catalin and Bakelite were within everyone's reach with Depression prices ranging from twenty cents to three dollars. Diana Vreeland, editor of Vogue, often spoke of the versatility of Bakelite, as did Elsa Schiaparelli, who was constantly contracting with the Bakelite and Catalin Corporations for exclusive buttons for her dress designs.
But in 1942 Bakelite and Catalin suspended sales of their colorful cylinders to costume jewelry manufacturers in order to concentrate on the wartime needs of a nation which had totally shifted its focus. Defense phones and aviator goggles, as well as thousands of other Bakelite products, found their way to armed forces around the world. The scheme shifted from the 200 vibrant colors which brightened the dark days of the Depression to basic black, the no-nonsense symbol of a nation at war. By the end of the war, new technology had given birth to injection-molded plastics, and most manufacturers switched to less labor-intensive and more practical means of developing products. The next generation of plastics had been born - Acrylic, fiberglass, and vinyl - and they were molded into products commonplace in our everyday lives today. Occasionally plastics are still improperly used and draw negative comments. The thousands of successful applications that contribute to the quality of our life are seldom noticed and are taken for granted. Remember, MATERIALS DON'T FAIL, DESIGNS DO.
The number of variations or formulations possible by combining the many chemical elements is virtually endless. This variety also makes the job of selecting the best material for a given application a challenge. The plastics industry provides a dynamic and exciting opportunity.
Plastics encompass a large and varied group of materials consisting of different combinations or formulations of carbon, oxygen, hydrogen, nitrogen and other organic and inorganic elements. Most plastics are a solid in finished form; however, at some stage of their existence, they are a liquid and may be formed into various shapes. The forming is usually done through the application, either singly or together, of heat and pressure. There are over fifty different, unique families of plastics in commercial use today and each family may have dozens of variations.
As eco awareness continues to expand and the availability of alternative options continues to increase and gain support, individuals and businesses seek ways to assess the sustainable aspects of various products. One recent result is the development of plastic ratings, like the new Plastics Scorecard. This scorecard, like other measures, will be a rating system for not only product manufactures to aspire to but a quick reference guide for consumers to make informed choices.
A similar pursuit is the International Resin Identification Coding system, which assigns an internationally accepted number from 1-7 to all plastics (resins). The number can be found on the bottom of plastic containers. This new scorecard will be another measure to increase eco awareness.
For manufacturing, plastic ratings are creating an immediate need for business sustainability improvements. According to Clean Production Action's Research Director, Mark Rossi, “The Scorecard is essentially a decision-making tool aimed at improving the design of plastic products.”
Aimed at helping manufacturers, purchasers and government agencies, this product transparency will hopefully move consumers away from the most hazardous types of plastics and switch to more-preferable options. Plastics will be given a grade of A+ to F rating based on their environmental and social impacts. This evaluation will take into account the full lifecycle of the product, from production to disposal.
Which materials were used in the development of the product?
Which manufacturing processes were used in the production of the product?
Does the product contain materials that could be detrimental to health?
Does the product contain materials that could be detrimental to the environment?
Is the product recyclable?
From the viewpoint of business, we believe that growing eco awareness and resulting pressure will dictate that best of the best products and services will continuously rise to the top. The key, like most improvement pursuits, will be engagement to reduce the production and use of undesirable plastics. I personally encourage everyone to be as much a part of the change as the business world. By increasing personal eco awareness and taking proactive steps to make changes in your daily life, individuals can create sustainable development in the market. Become aware of your plastic alternatives and drive change through informed choices.
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Sources : Wikipedia, Google, Yahoo, MSNBC.
Here is the thing, if Facebook is a country then it will make it the fifth biggest nation in the world with more than 175 millions members and still counting. It has more population than Japan as a country. This site was actually started from a brilliant idea from a college student Mark Zuckerberg and his classmates at Harvard University Dustin Moskovitz, Eduardo Saverin, and Chris Hughes who were thought that it would be so much fun if you can get connected with anyone you want in the whole world. How fun it would be if you can exchange pictures and messages with your old mates that you haven’t seen for ages only with one click and only took like thirty second of your precious time. The good thing about this site is you, yourself, are the one who’s in control on your own profile. So yeah, am very sorry for anyone who’ve got done by this site over their own stupidity, that was not counted at all in what am going to said about this networking site. Seriously guys, this web is supposed to be a fun thing. Yeah, of course you can take it serious as some people do, but once again, you are the person who is in charge on your personal thing that you put in your profile and that was what I like about it.
