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COMPUTERS – A BLESSING OR CURSE ? ADVANTAGES OF COMPUTERS |[pic][pic] |Is computer education important in India? | | |What are the advantages of computers for young children? | | |What about the disadvantages of computers? | | |How do the advantages and disadvantages compare? | | |What is children’s computer education?
KIDS AND COMPUTER | | |EDUCATION. | | |How do children learn computers? | | |Which is the right age to get them started and what should be | | |their minimum skills? | | |Is there an maximum age learn to use the computer? Any benefit to| | |starting early? | |What role does educational software play ? | | |What role do popular characters play in developing computer | | |literacy? | | |How can parents help in developing computer literacy? | | |What is the role of computers in the lives of young children? | |What can we conclude from this discussion? | Why is computer education for young children a growing concern? Over the past few years, computers have become a vastly popular household item. The luxury of emailing messages as opposed to charging up the phone bill is more appealing. Checking news, weather, and sports via the Internet is a convenience that many are taking advantage of. Our children’s lives are already getting influenced by technology – and this is just the beginning.
Computers and Internet are here to stay and software titles targeting young children continue to increase. Computer science is has become a compulsory subject in Indian schools. Today, We find computers in use everywhere, whether we go to reserve a train ticket or to a Bank. This is because it is faster and helps us complete our work without mistakes/errors. So Parents too have realized the need to help their children develop strong computer skills. Children are learning to read and write with computer games instead of homemade flash cards. They are reading their bedtime stories online instead of in bed with their parents.
Slowly traditions are being broken and the computer is becoming a child’s learning tool. Many parents are buying computer learning games instead of board games and pop-up books. Parents are leaving the learning up to the computers and spending less quality time with their children. The most important learning step for children is interaction with others. If they are sitting in front of the screen all day, they do not learn to share, wait their turn, or even something as simples as manners. Children need to be in contact with other children, adults, and animals. They need to experience things first hand not off a computer screen.
When children log on to the computer their innocence is noticeable. Children are an easy target for adults who pose to be other children with similar interests. Sexual offenders often chat online with children and then make plans to meet them or slowly filter information about them. Children are innocents and honesty on the computer can pose some huge problems. They do not know any better and usually it will only harm them in the end. One benefit of the computer age is that children are becoming smarter. They are growing up computer literate and will have that as a huge advantage.
Computer literacy is becoming a huge job qualification and feeling comfortable with one will put them a step ahead. Children will also be able to complete homework on line. In some places, if you miss school you can find out the assignments that you miss and catch up. This is very helpful if your child comes down with the flu, but do you want them to feel like it is okay to miss school because they can catch up with their computer? Overall, children can benefit from computers if they are used wisely. Parents that supervise their children when they are on the computer can ensure that everything is happening safely.
Computers are the wave of the future, but old fashioned learning techniques should not be forgotten. A child needs to interact physically with other people and not learn everything from computers. |[pic][pic] |What are the advantages of computers for young children? | | |Computers help children to be in control of their experience, to set their own pace, and to select| | |the level of challenge with which they feel comfortable. | | |Computers help children to use all of their senses to extract information.
Computers fascinate | | |kids and can draw their full attention, which often results in a deeper focus and concentration. | | |Computers enable children to learn through creating, just as they gain hands-on knowledge and | | |understanding when they build forts, make up stories, and paint, increase their skills | | |As they master computers, children build positive attitudes toward technology that will pay | | |dividends for the rest of their lives. |
Computers benefit the development of fundamental skills… Good educational software enables children to develop and practice a broad range skills. It can help them learn, for example, about letters, numbers, shapes, colors, and rhythm. Good software can also help children develop their understanding of cause and effect, higher order problem solving, procedural thinking, and creative expression. Today, the wide range of multimedia available for kids in India is really amazing. Emotional skills: By using a computer children develop self-confidence and self-esteem as they master computer skills and use the computer to make things happen.
This also gives them a reason to smile! Social skills: In the classroom setting or in the home when their friends or parents are available, children often prefer working with one or two partners over working alone, which leads to the development of social skills. Computers benefit children with special needs… Computers have proven extremely beneficial to kids with certain speech, audio, and motor limitations. Kids with special needs can use alternative input and output devices (assistive technologies) to interact with computers and do things that they normally could not accomplish independently.
They benefit especially from having access to an on-demand, patient tutor that allows them to work at their own pace. What they achieve through using a computer enhances their self-esteem and provides them with a greater sense of control and engagement with the world. The internet provides them with the best of knowledge for their treatments and they can be in touch with doctors or friends through the internet, in India or Abroad. Also, the internet can later help them earn their means of livelihood. What are the disadvantages of computers for young children?
Computers are very engaging and can exercise a strong “holding power” on children as well as adults. They really seem to mesmerize children. Since we do not yet understand the impact of this power, we need to monitor the amount of time a child spends before a computer. If the software is not age-appropriate, children are likely to become frustrated and associate a computer with failure. Kids with access to software that is not age appropriate may be exposed to such negative influences as violence, strong language, and over-stimulation from fast-action graphics.
Frequent and prolonged computer sessions may pose physical health risks for children. The most frequently cited are visual strain, harmful effects of radiation, and posture and skeletal problems. In the case of normal usage and normal operating conditions, however, research has shown that computer monitors are safe and do not compromise the health of our eyes and that computer monitors emit little or no harmful radiation. What does seem to pose a hazard is the strain placed on a child’s posture and skeletal structure if she consistently uses a computer set-up designed for an adult.
For Surfing the Internet, parental involvement & control is a must. How do the benefits and drawbacks compare? Overall, the benefits seem to outweigh the drawbacks. And, the fact is, actively involved parents can control most of the drawbacks. This puts even greater responsibility on parents to be vigilant and conservative in their judgment about their children’s computer usage. A regular and constant watch is very necessary, especially regarding the internet. Although cyber laws in India are trying to regulate the content within Indian sites, the Internet hold no barriers since it is a World Wide Web.
Parents could install parental control tools to prevent children from going to undesirable sites. Just what is children’s computer education. Years ago, computer literacy was defined in terms of specific knowledge of computer technology and terminology. Today, it is regarded more as a continuum of awareness, skills, experience, and attitudes based on the age and capabilities of the individual child. 1. An awareness of what the computer can do – that it is a tool for learning and finding out about things, and for expressing and creating things. 2.
An awareness of ideas and behavior that are a part of the computer culture, such as knowledge of safe behavior on the Internet. 3. Basic operational skills learned by immersion in a variety of software programs. 4. A body of successful experiences that over time develop within a child an intuitive feel for dealing with new things that he encounters in a computer environment. Typical examples are how to navigate a new program and how to “trouble-shoot” when something isn’t working. 5. An attitude of discovery, mastery, purposefulness, and pleasure in using computers. How do children gain computer literacy? Is there a series of steps?
Children develop computer literacy by observing others at the computer and by diving in and actively exploring different software programs. As with learning to read, each child will progress at the rate appropriate to that child. By and large, children are curious and pick up fast. There are lots of computer classes in India which specially specially cater to young children. STEPS:- Exposure and observation: A child’s relationship with the computer typically begins with the child watching a sibling, parent or classmate busy at the computer. She eventually crawls up on Daddy’s lap, and through the so-called Daddy Interface” has her first computer experiences, passive in nature. Active participation: The child quickly moves from observer to active participant, grabbing at the mouse, banging on the keyboard, and pointing at things that excite her on the screen. The parent, however, still operates the software. Taking control: Eventually, the child learns how to control a mouse or trackball and subsequently how to control what is happening on the computer screen. Using her newfound “point and click” and “click and drag” skills, she can now actively explore a software program.
The computer is my tool: With greater control, the child begins to see the computer more as her tool – something she can use to make and find things. Increasingly, she approaches the computer with a goal, for example to find dinosaurs or or click on something colorful or moving. Mastering skills: As she plays with different software programs, a child develops a general sense of how to navigate through simple environments, how to start and quit an activity, and how to operate specific programs. Although she may still rely on a parent or sibling for many functions, she is rapidly mastering an impressive skill set.
Independence: Most children with consistent access to a computer over the period of a couple years are eventually able to power up the machine, start up a pre-loaded application either from the hard disk or a CD-ROM, quit an application, operate the printer and scanner, access the Internet from the desktop, and even send an email. At what age can children reasonably begin to develop computer literacy? What underlying development skills do they need to possess? Certainly a baby can watch animations unfold across a computer screen. But computer control and interaction with software requires certain developmental skills.
As these skills develop, a child will gain more and more benefit from using a computer. Babies and Young Children: Passive Observers At this age, kids are able to sit on a parent’s lap and watch the activity on a computer screen. They have the curiosity, attention span to track and enjoy the media experience. This relatively passive computer experience with the parents, however, is not very different from being read to or watching a TV program, with the parent making the effort to connect the child with the media. Three-Year-Olds: Ready, Set, Go
A few essential skills are required for directly controlling a computer software program. Children must first have adequate fine motor skills and hand-eye coordination to operate a mouse or track ball. Second, they must possess the cognitive skills of causality and vertical/horizontal transfer in order to understand that what they are doing with the keyboard or mouse is making things happen on the computer screen. They also need to possess the related skill of knowing what is up, down, right and left, so that they can control which direction they want the cursor to move on the computer screen.
Typically these capabilities are present in the three to three-and-half-year-old. This is when becoming proficient with a mouse is a quasi-effortless, rapidly acquired skill. Although many two’s are able to control a mouse, for most younger children, it is a struggle and it is better to simply wait until they are ready rather than build up frustration and negative feelings toward the computer. With basic mouse skills, three-year-olds can explore and experiment with cause and effect in simple environments like interactive stories and play rooms.
They can also dabble with basic draw and paint programs and enjoy sing alongs, finding games and other activities that are simple to control. Preschoolers and Kindergartners: Computer Explorers As children move through pre-school into kindergarten, their insatiable curiosity, growing attention span, increasing memory, and developing cognitive skills make for an increasingly richer, more independent experience. They can stay with an activity longer, remember more about where things are and how to get where they want to go in a program, and they can enjoy a broader range of content and activities.
They move from simple cause and effect experiences to acquiring readiness and problem-solving skills through structured activities, creating illustrated stories and multimedia pictures with graphics programs, and even using visual reference programs like Microsoft Encarta to answer their many “why’s? ” At this stage, four and five year olds become computer “explorers”, never tiring of finding more things to do with a program and the computer. First and Second Graders: Computer Competency As children enter elementary school, their computer experience continues to broaden with their emerging reading and writing skills.
Programs that require or revolve around some reading come within their reach, and they can supplement their learning in school with subject-specific software programs, from the three “Rs” to science and geography. Their more sophisticated logic and problem-solving skills enable them to enjoy puzzles, strategy games and building and simulation programs. Their ability to follow longer multi-step procedures allows them to use more sophisticated creativity programs to make slide shows, theater productions, paper doll designs, even animations.
The text-heavy Internet starts to become more comprehensible, and as their sense of the world broadens, email and correspondence with children from far away places becomes more comprehensible and exciting. Their facility with the printer and other input and output devices gives them control over a wide range of creative “productions. ” Is there an optimal age for a child to learn to use the computer? Is there a benefit to starting early? Rather than predicating an age, it is best to allow the child to take the lead.
As in the case of reading and writing, her own readiness should drive when she starts using a computer and at what pace she develops her computer skills. Since most children seem to “catch up” whenever they start using a computer, parents needn’t worry that their child will fall behind on computer skills if she doesn’t demonstrate an interest at an early age. |What role does educational software play in developing computer literacy? |[| |In short, everything. The computer is a tool and the software tells the computer what to do. Accordingly, the value of the |p| |computer for a child is as good as the experience provided by the software.
Having access to a library of high-quality age |i| |appropriate titles spanning the product categories relevant to kids (e. g. creativity, storybooks, and reference) is essential |c| |for enjoying the full benefits of a computer. |]| | |[| | |p| | |i| | |c| | |]| What role do popular characters play in developing computer literacy?
Popular characters from across the media spectrum have migrated into the world of early learning software. In a positive sense, characters and stories are what engage us in the act of reading or watching a movie. It is therefore no surprise that this is often what draws a child into playing with a computer. The warmth, familiarity and context of the story step the child into the other aspects of the software program. Whether software featuring a popular character is a positive experience for the child or a negative one depends more on other design aspects of the software, including the actual learning experience.
A character can lead a child into a program but leave her stranded in a content-poor, non-intuitive, and ultimately frustrating environment. A well-loved character teamed up with a well-designed learning experience, however, can be a strong recipe; the character will lead the child in, but rewarding opportunities for discovery and learning will keep her engaged. What role do parents play in developing computer literacy? Parents play a critical role in shaping their child’s development in general, and computer literacy is no different.
First, they are in control of what kind of computer set-up the child has, where the computer resides in the household, and what kind of access the child has to the computer. As noted above, parents also purchase the software their child plays with. And as we have seen, software is everything, so parental knowledge and judgment in this area have a major impact on what a child gains from the computer. Once the computer is set up and software is purchased, there is the question of how productive and beneficial a child’s time on the computer will be.
The parent has an important role to play here as facilitator. Young children typically need an adult to guide their discovery process and to ensure that they challenge themselves. Monitoring a child’s computer usage is just as essential. By reviewing hard copy output of a child’s computer activities, for example, the parent can track her abilities to accomplish the task at hand. This enables the parent to supplement learning or introduce new experiences and challenges at the right time. What is the appropriate role of computers in the lives of young children?
Given the important benefits of computers and parental ability to control many of their drawbacks, computers have a positive, useful role to play in the development of young children. However, this role must be carefully circumscribed, as computers can be misused and cannot provide all of the kinds of experiences that are critical to a young child’s development. MOST OF ALL ALWAYS REMEMBER THIS “Computers supplement and do not replace highly valued childhood activities and materials, such as art, blocks, sand, water, books, exploration with writing materials, and dramatic play. In other words, the computer is an enrichment tool for enhancing readiness skills, problem-solving, and creative expression. It adds another dimension to concrete exploration and expression, like playing with sand, puzzles and crayons. The good news is that most parents, teachers, and kids in particular seem to know this intuitively. Young children flit between blocks, dress-up, drawing, books, the computer, and other favorite activities according to their spontaneous interest. They will rarely sit at a computer for more than fifteen minutes at a time and not more than a few sessions per day, if the computer is left on.
What can we conclude from this discussion? Computers offer substantial benefits to young children and their development, and to families as a whole. At the right age, a computer is a wonderful thing that every child deserves to have. Accordingly, if a family can afford a computer without sacrificing other important, traditional childhood experiences, then this environment should contain a computer set-up that can be accessed as easily as books and other playthings and integrated in the family’s day-to-day activities in a natural way.
The actual benefit of a computer to a child depends primarily on: • The quality of parental involvement • The quality of educational software that the child is using • Following developmentally appropriate practices in the way the child uses the computer • Achieving a balanced role for the computer in the child’s life as one important element in the mix of quality learning and play opportunities With parental guidance, quality software, Parental control software, safe surfing tips, and their own love of discovery and learning, young children can work wonders with computers & the internet.
They can also gain and reap the benefits of computer literacy for the rest of their technology-filled lives. [pic][pic] It’s Plastic Decoding Plastics Disposing of Plastic Recycling Plastics How Plastic is Recycled Energy from Plastic Paper or Plastic? Degradable Plastic IT’S PLASTIC! Americans seem to have a love–hate affair with plastic. We look down on plastic imitations of natural products and fibers. They are cheap, we say. We all want real leather, for example, rather than imitation plastic. Yet we are using plastic products more than ever before.
We cover our food in plastic wrap, drink coffee from Styrofoam® cups, wear clothes made from man-made fibers like nylon, polyester, and rayon, and even buy our plastic things with plastic credit cards! We use plastic hundreds of times every day. Plastic is a versatile product. Plastic can be flexible or rigid; transparent or opaque. It can look like leather, wood, or silk. It can be made into toys or heart valves. Altogether there are more than 10,000 different kinds of plastics. The basic raw materials for plastic are petroleum and/or natural gas.
These fossil fuels are sometimes combined with other elements, such as oxygen or chlorine, to make different types of plastic. Plastics are not the waste and energy culprits that some people think they are. Plastics are really very energy efficient. It takes 20-40 percent less energy to manufacture plastic grocery bags than paper ones. And, since plastics are lightweight and take up so little space, it is much more efficient to transport them. It takes seven trucks to deliver the same number of paper bags as can be carried in one truckload of plastic bags.
DECODING PLASTICS [pic]PET Polyethylene Terephthalate Two-liter beverage bottles, mouthwash bottles, boil-in-bag pouches. [pic]HDPE High Density Polyethylene Milk jugs, trash bags, detergent bottles. [pic]PVC Polyvinyl Chloride Cooking oil bottles, packaging around meat. [pic]LDPE Low Density Polyethylene Grocery bags, produce bags, food wrap, bread bags. [pic]PP Polypropylene Yogurt containers, shampoo bottles, straws, margarine tubs, diapers. [pic]PS Polystyrene Hot beverage cups, take-home boxes, egg cartons, meat trays, cd cases. [pic]OTHER
All other types of plastics or packaging made from more than one type of plastic. DISPOSING OF PLASTIC |ANOTHER look | |PLASTICS RECYCLING IN AMERICA | | | |Today, Americans recycle only 5 percent of all the plastics produced in this | |country. Why aren’t we recycling more? There is no simple answer. | |Part of the issue in recycling plastics is the cost.
To remain competitive in | |the global marketplace, manufacturers usually choose the cheapest option for | |making products. New plastic resin, or virgin resin, often costs less than | |recycled plastic. Until recently, when the U. S, experienced massive | |hurricanes, virgin resin was cheaper than recycled plastic. After the | |hurricanes in 2005, supplies of oil and natural gas–the building blocks of | |virgin resins–became limited and more expensive. Prices for virgin resin | |soared, and the demand for recycled plastics increased. | |Another important consideration is human behavior.
Surveys conducted by | |Proctor & Gamble and other companies show that while most people expect their | |plastic to be recycled, they won’t go out of their way or pay a few cents more| |to buy products made of recycled plastic. | |There are success stories in plastics recycling, nonetheless. Soft-drink | |bottles made of polyethylene terephthalate (PET) can be melted down and made | |into carpet, t-shirts, stuffing for ski jackets, or molded into bottles again. | |In 1999, Ford Motor Company used more than 60 million 2-liter plastic soda | |bottles (7. million pounds) to make grille reinforcements, window frames, | |engine covers and trunk carpets for its new vehicles. | |[pic] | |In recent years, several plastics recycling companies have closed their doors. | |They claimed they could not sell their products at a price that would allow | |them to stay in business. Thanks to the relatively low cost of petroleum | |today, the price of virgin plastic is so inexpensive that recycled plastic | |cannot compete.
The price of virgin resin is about 40 percent lower than that | |of recycled resin. | |Because recycled plastic is more expensive, people aren’t exactly lining up to| |buy it. Surveys conducted by Procter & Gamble and others show that while most | |people expect their plastic to be recycled, they won’t go out of their way or | |pay a few cents more to buy a bottle made of recycled plastic. Recyclers say | |plastics recycling won’t be profitable until we close the loop by creating | |more demand for recycled plastics. | |Soft-drink bottles, however, are one success story in plastics recycling.
Made| |of polyethylene terephthalate (PETE), they can be melted down and made into | |carpet, t-shirts, stuffing for ski jackets, or molded into bottles again. When| |a soft-drink bottle is recycled into another soft-drink bottle, the loop is | |closed. | Is plastic trash choking the Earth with Styrofoam® cups and fast-food plates? Not really. That’s just another misconception. By weight, plastics make up about 11 percent of America’s municipal solid waste. In comparison, paper makes up about 35 percent. Of course, plastics are generally very lightweight.
When plastics are buried in a landfill, they occupy about 25 percent of the space. Putting plastics into landfills is not always the best disposal method. There are two other alternatives: recycling and incineration. These methods recover some of the value from the plastic. Recycling recovers the raw material, which can then be used to make new plastic products. Incineration recovers the chemical energy, which can be used to produce steam and electricity. Landfilling plastics does neither of these things. The value of landfilled plastic is buried forever.
RECYCLING PLASTICS Recycling plastics is easy. First, you should learn what types of plastics can be recycled and only give your collector those types of plastics. Resist the temptation to slip plastics that recyclers don’t want into the recycling bin. Plastics have different formulations and should be sorted before they are recycled to make new products. Mixed plastics can be recycled, but they are not as valuable as sorted plastics because the recycled plastic’s physical properties, such as strength, may vary with each batch.
Once you know what kinds of plastics your recycler wants, you should follow the wash and squash rule—rinse the container and squash it. You may leave the paper labels on the container, but throw away the plastic caps. Plastic caps are usually made from a different type of plastic than the container and cannot be easily recycled. HOW PLASTIC IS RECYCLED A recycling plant uses seven steps to turn plastic trash into recycled plastic: [pic]1. Inspection Workers inspect the plastic trash for contaminants like rock and glass, and for plastics that the plant cannot recycle. . Chopping and Washing The plastic is washed and chopped into flakes. [pic]3. Flotation Tank If mixed plastics are being recycled, they are sorted in a flotation tank, where some types of plastic sink and others float. 4. Drying The plastic flakes are dried in a tumble dryer. [pic]5. Melting The dried flakes are fed into an extruder, where heat and pressure melt the plastic. Different types of plastics melt at different temperatures. 6. Filtering The molten plastic is forced through a fine screen to remove any contaminants that slipped through the washing process.
The molten plastic is then formed into strands. 7. Pelletizing The strands are cooled in water, then chopped into uniform pellets. Manufacturing companies buy the plastic pellets from recyclers to make new products. Recycled plastics also can be made into flowerpots, lumber, and carpeting. ENERGY FROM PLASTIC Because plastics are made from fossil fuels, you can think of them as another form of stored energy. Pound for pound, plastics contain as much energy as petroleum or natural gas, and much more energy than other types of garbage. This makes plastic an ideal fuel for waste-to-energy plants.
Waste-to-energy plants burn garbage and use the heat energy released during combustion to make steam or electricity. They turn garbage into useful energy. So, should we burn plastics or recycle them? It depends. Sometimes it takes more energy to make a product from recycled plastics than it does to make it from all-new materials. If that’s the case, it makes more sense to burn the plastics at a waste-to-energy plant than to recycle them. Burning plastics can supply an abundant amount of energy, while reducing the cost of waste disposal and saving landfill space. PAPER OR PLASTIC? A paper cup or a plastic cup?
Should you choose paper cups over plastic cups since the paper cups are made from natural wood products and will degrade? Not if the plastic cup is polystyrene (another name for Styrofoam®). A study by Canadian scientist Martin Hocking shows that making a paper cup uses as much petroleum or natural gas as a polystyrene cup. Plus, the paper cup uses wood pulp. The Canadian study said, “The paper cup consumes 12 times as much steam, 36 times as much electricity, and twice as much cooling water as the plastic cup. ” And because the paper cup uses more raw materials and energy, it also costs 2. times more than the plastic cup. But the paper cup will degrade, right? Probably not. Modern landfills are designed to inhibit degradation so that toxic wastes do not seep into the surrounding soil and groundwater. The paper cup will still be a paper cup 20 years from now. Learn more about how long it takes buried trash to disappear. DEGRADABLE plastic Degrade is another word for rot. It’s nature’s way of getting rid of dead plants and animals or the things made from them. Of course, plastics are man-made materials, but scientists have figured out two ways to make plastics degrade: biodegradation and photodegradation.
Biodegradable plastics are made with five percent cornstarch or vegetable oil. The idea is that hungry bacteria will devour the starch or oil in the plastic, causing the plastic to disintegrate into a fine dust. That is the idea, but does it really work? No, say both environmentalists and plastics manufacturers. Nothing degrades quickly in a modern landfill, not even organic wastes like paper and food scraps, so there is no reason to think that the corn starch in biodegradable plastics will disappear overnight either. Modern landfills are designed to inhibit degradation, not promote it.
The idea is to keep wastes in, so landfill contaminants do not seep into the surrounding environment. In addition, biodegradable plastics cannot be recycled because the starch or oil additive compromises the quality of recycled plastics. Photodegradable plastics are a different matter. They use no organic additives. They are made with a special type of plastic that breaks down and becomes brittle in the presence of sunlight. Of course, that means photodegradable plastics do not break down when they are covered by leaves or snow, or when they are buried in a landfill.
The maker of the plastic six-ring carrier that is used to attach six cans of soda, beer, and other beverages, says its photodegradable carrier loses 75 percent of its strength when exposed to sunlight after just a few days, and totally disintegrates within a matter of weeks. This means if an animal were to become entangled in the six-ring carrier, it could rip through the weakened pack to free itself. Since photodegradable plastics contain no organic additives, they can also be recycled, unlike their biodegradable cousins. Last Revised: September 2006 Source: National Energy Education Development Project, Museum of Solid Waste , 2006
EIA Main Home Page • Related Links • Kid’s Page Privacy • Contact Us |An Introduction to the History of Plastics |[pic] | | | |Plastic Recycling and the Environment | |Although plastics have had a remarkable impact on our culture, it has become increasingly obvious that there is a| |price to be paid for their use. | | |The first controversy arose in the late 1950s and early 1960s. There were a number of incidents where small | |children crawled into plastic bags used by launderers to cover clothing, and suffocated. The plastics industry | |managed to fend off trouble by launching a massive public-education campaign. | | | |By the late 1960s, plastics were increasingly seen as a symbol of an outdated 1950s consumer culture. The term | |”plastic” became an insult, used to describe someone thought of as soulless.
At the end of the 1960s, the | |Beatles would even sing of “Polyethylene Pam,” a “go-getter” who would do anything to get ahead. | | | |This was partly just a fashion statement, since plastics remained in widespread use anyway, and in many cases | |were much more effective and environmentally benign than alternative materials. However, this led to a problem | |as well, since the consumption of massive amounts of plastic goods led to a massive problem with litter and waste| |disposal. | | |Plastic was almost too good, as it was durable and degraded very slowly. In some cases, burning it could release| |toxic fumes. There was also the problem that manufacturing plastics often created large quantities of nasty | |chemical pollutants, and depleted the Earth’s bounded supply of fossil fuels. | | | |By the 1990s, plastic recycling programs were common in the United States and elsewhere.
Thermoplastics can be | |re-melted and reused, and thermoset plastics can be ground up and used as filler, though the purity of the | |material tends to degrade with each reuse cycle. There are methods by which plastics can be broken back down to | |a feedstock state. | | | |Products such as automobiles are now being designed to make recycling of their large plastic parts easier.
To | |assist recycling of plastic disposable items, the Plastic Bottle Institute of the Society of the Plastics | |Industry devised the now-familiar scheme to mark plastic bottles by plastic type. A recyclable plastic container| |using this scheme is marked with a triangle with three “chasing arrows” inside of it, which enclose a number | |giving the plastic type: PETE, HDPE, PVC, LDPE, PP, PS, and OTHER (for more info see plastic packaging resins). | |Unfortunately, recycling plastics proved difficult.
The biggest problem with plastic recycling is that it is | |difficult to automate the sorting of plastic waste, and so it is labor-intensive. While containers are usually | |made from a single type and color of plastic, making them relatively easy to sort out, a consumer toy like a | |cellular phone may be made of many small parts consisting of over a dozen different types and colors of | |plastics. As the value of the material is low, recycling plastics is unprofitable. For this reason, the | |percentage of plastics recycled in the US is very small, somewhere around 5%. | | |Research has been done on “biodegradable” plastics that break down with exposure to sunlight. Starch can be | |mixed with plastic to allow it to degrade more easily, but it still doesn’t lead to complete breakdown of the | |plastic. Some researchers have actually genetically engineered bacteria that synthesize a completely | |biodegradable plastic, but this material is expensive at present. | | |So far, these plastics have proven too costly and limited for general use, and critics have pointed out that the | |only real problem they address is roadside litter, which is regarded as a secondary issue. When such plastic | |materials are dumped into landfills, they can become “mummified” and persist for decades even if they are | |supposed to be biodegradable. | | | |There have been some success stories.
The Courtald concern, the original producer of rayon, came up with a | |revised process for the material in the mid-1980s to produce “tencel. ” Tencel has much superior properties to | |rayon, but is still produced from “biomass” feedstock, and its manufacture is extraordinarily clean by the | |standards of plastic production. Whether the use of plastics can be made completely consistent with | |environmental quality demands, still remains to be seen. | |Some interesting plastic recycling sites: Plastics Resource, Recycler’s World, Plastics. org. Yahoo | | | | | |Plastic Polymers | Celluloid & Rayon | Bakelite | Polystyrene & PVC | Nylon Synthetic Rubber | A | |Plastics Explosion | Plastic Recycling | Packaging Products | | | | | | | | |