Category Archives: General Knowledge

Selecting Plastic Animal Cages

 source: http://www.animallab.com/articles.asp?pid=121

Selecting Plastic Animal Cages
By Dave Demorotski
September/October 2005

Buying on price is one way. But if you can answer a few what’s and how’s about your facility caging needs and procedures, you can purchase cages that will last longer plus add value.

For many, selecting the right plastic caging for housing rodents can be a “poly nightmare.” There’s “poly-this type cage” and “poly-that type cage.” And the “poly-that type cage” must be better because it costs 20% more than the “poly-this type cage.” Yet the “poly-that type cage” didn’t last 20% longer because it became cloudy and hazy after only a few times through washing and sterilizing cycles.

So how should you determine what is the right caging to buy for your vivarium? The best answer probably lies in understanding how your cages are used and how they move through your facility… from the animal housing room to washing/sterilizing, to storage and back to holding the animals. Below are some questions to consider that can help you determine which plastic cages may best serve your facility.

Questions to Consider Before You Buy
• First, of course, is how many new plastic cages does your facility need? Do you have an absolute minimum (number of cages) to purchase or is there a budgeted amount to spend?
• What is the budget level or limitation?
• How long does the caging need to last?
• For what type of research are the cages being used?
• Does the study require only a one time or very limited use?
• Does it involve dangerous or toxic materials that need disposal? Or, do the cages just need to last as long as possible?
• How frequently do you changeout cages?
• How is the caging handled throughout your facility? What processes will they go through? For example, how is the soiled bedding removed, by hand or mechanically? How is sticky bedding removed? How are the cages transported and stored? In general, how much does your caging get knocked around in moving it from the animal lab through cleaning and sterilizing and back to the animal room?
• What kind of detergents are used in cleaning? How much alkali does the detergent have, <pH7.0?
• How hot is the water? Is it hard or soft water? Is the rinse cycle sufficient to make sure all residue is removed?
• What chemicals are used to disinfect your plastic cages?
• Will the cages be autoclaved? What are the usual autoclave settings? Are amine corrosion inhibitors added to the central boiler steam supply to protect the pipes? Will the cages be autoclaved with the bedding, feed, and water bottles in them? If so, what type of bedding is used?
• Finally, how will the sterilized cages be stored? How high will they be stacked?

Okay, so it’s more than a few questions. But the more you can find out about how the cages are handled and treated within your facility, the better you will be able to select the type of plastic that will serve your requirements, at the price you can afford.

Suppliers and cage manufacturers conduct a variety of
tests on polymers. Most are to determine durability, chemical resistance, material clarity and steam resistance. This photo highlights an autoclave test of materials at 270° F for50 cycles under induced stress levels of 500 psi.

Selecting the Appropriate Type of Plastic Cage
Once you have completed your cage usage/care review and determined your caging requirements and budget, you can begin to quickly narrow the plastic options to the one or two polymers that will best fulfill your needs.

POLYSTYRENE OR POLYETHYLENE – These materials are low temperature and cannot be used in an autoclave. Polystyrene begins to distort at temperatures over 176°F (80°C) and polyethylene at temperatures over 200°F (93°C). The cages are rigid and are relatively low cost. For these reasons, cages of these materials are usually considered disposable and used in studies involving dangerous mate rials such as radiation. Polystyrene is a clear material so it is easy to view the animals, but its toughness and abuse resistance is fairly low. Polyethylene is opaque or translucent while offering a much higher level of impact resistance than polystyrene.

POLYCARBONATE (PC) – Polycarbonate is a popular material for animal cages and water bottles. It is also relatively inexpensive. PC can’t take the higher autoclave temperatures (>250°F/121°C) or the steam very well. It most likely will distort in the autoclave because of the temperature. Also, PC wants to absorb water (steam) which leads to its molecular breakdown evidenced by stress cracking after only a few sterilizer cycles. Stress cracking also occurs from chemical cleaning solutions such as alkalai and strong acid detergents as well as aromatic and chlorinated hydrocarbons.

HIGH HEAT POLYCARBONATE (PPC) – High heat PC is much the same as polycarbonate, just a little higher temperature tolerant (>270°F/132°C). The heat distortion is higher than PC, but the chemicals that attack it and the water absorption problem remain about the same.

POLYETHERIMIDE (PEI) – This polymer doesn’t have great impact strength to start and degrades further after autoclaving. It can withstand higher temperatures, up to 400°F (204°C), than the polycarbonates. It has good chemical resistance, especially against acidic detergents and organic solvents, but is susceptible to breakage because of its initial brittleness. PEI has very poor resistance to low pH solutions of alkaline chemicals. PEI should not survive more than 50 autoclave cycles unless it is given tender loving care. PEI is dark in color which doesn’t allow for much light transmission and makes it more difficult to view animals inside the cages.

POLYSULFONE (PSU) – Polysulfone can withstand higher temperature than PC or high heat PC, about 300°F (149°C) and should withstand about 100 autoclaves with minimal affect. PSU has good chemical resistance to all commercial cage cleaners, only being attacked by high levels of ionic surfactants. While polysulfone is completely unaffected by pure steam, amine corrosion inhibitors used in some central steam supply systems can cause crazing and cracking in areas of cages under high stress. It can also be attacked by ketones, aromatic and chlorinated hydrocarbons.

POLYPHENYLSULFONE (PPSU) – This is the highest level of the transparent polymer materials. Polyphenylsulfone offers great chemical resistance, great steam sterilizing (up to 380°F/193°C) capability, and high impact strength. Heat deflection begins to appear at the high range above 400°F (204°C). Tests have shown PPSU to withstand 2000 autoclave cycles with very little affect. PPSU also shows good to excellent resistance to both inorganic and organic cleaning chemicals. The hindrance to PPSU is a somewhat higher cost than other polymers used for animal cages.

A Little TLC Can Go a Long Way
As described above, the main areas that can determine the longevity of your plastic cages are its chemical resistance, steam resistance and toughness. If you follow some of the practices listed here, you may increase the useful life of your plastics.

Handling
Be as careful as possible in handling and transporting cages. In particular, avoid hitting or banging the plastics against hard surfaces. One common practice to avoid is hitting the cage against a surface to remove soiled and stuck bedding. This can significantly shorten the life of your cages. Even the higher end polymers with greater impact strength lose some of their resistance after repeated chemical cleanings and sterilization. To remove stubborn bedding, it is best to use a soft polymer spatula or scraper. Do not use a metal scraper because it can scratch the plastic surface.

Also, do not overstack the caging, especially cages with bedding. The stress on the lower cages can cause cracking. Again, this is especially true for older cages that have been through several cleaning cycles. As a general rule, mouse cages should not be stacked more than 15 high. Rat cages should not be stacked more than ten high.

Washing
Plastic cages and bottles should be washed in hot, soft water with a manufacturer recommended detergent solution. Washing plastics in hard water could cause a milky-gray discoloration on the surface after frequent washing. Optimum water temperature is in the 140°-150°F (60°-66°C) range. A short rinse at approximately 180°F (82°C) is helpful for disinfection.
If an alkaline detergent is used, a short acidic rinse cycle followed by a final fresh water rinse is recommended. In general, selecting a detergent with a pH between five and seven will work well for most polymers.

Be sure all residue is removed from cages and bottles by the final rinse. This is especially important if autoclaving is to follow. The extreme heat of autoclaving will most likely cause the residue to be baked onto the plastic, resulting in loss of clarity and gradual deterioration.

To help prolong the life of your plastic materials, you should consult your cage wash supplier to ensure that the cycle times and temperatures are correct for the plastics you are using.

Disinfecting
There are many disinfectants that can harm plastics. Check with your disinfectant supplier regarding the use of their products for your particular plastic materials. You should NEVER heat cages that contain a disinfectant residue.

Autoclaving
It is important that plastic cages and bottles are washed, thoroughly dried, and free from any residue before autoclaving. Effective autoclaving depends upon proper temperature controls and appropriate steam supply. Autoclaves should be regularly checked to ensure effectiveness.

While polycarbonate (PC) is considered autoclavable, it will deteriorate after repeated autoclaving. It is recommended that PC cages should be autoclaved only on an as needed basis and at a temperature no greater that 250°F (121°C) for a short cycle, about 20 minutes.

While cages with bedding, feed, and water bottles can be autoclaved together, it is important to note that heating these combined materials may possibly release damaging substances which can attack the plastic. This could cause clouding and/or cracking of the polymer material.

For steam sterilization systems supplied by a boiler feed, check for the use of corrosion inhibitors with amine. These could also dull or damage the plastic material.

Summary
Answering a few questions regarding the chemical, disinfecting/sterilizing procedures and how your plastic cages are handled within your facility should be the first part of your selection process. Finding answers to the chemical and steam resistance as well as impact strength of the various plastic resins you are considering for your cages is the second step. Finally, determine your budget and longevity goals. With these answered, you will be able to select the plastic animals cages that will best serve the needs of your facility.

Dave Demorotski is Marketing Manager of Alternative Design Manufacturing & Supply, Inc., 3055 Cheri Whitlock Dr., Siloam Springs, AR 72761;479-524-4343;
dave@altdesign.com; www.altdesign.com.

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Plastic? You Might Be Chewing It

source: http://www.technologyreview.com/Nanotech/19486/

Nonstick Chewing Gum

A U.K.-based company is set to launch a new kind of chewing gum that’s easy to wash off any surface.

By Prachi Patel-Predd


Most everyone has had the displeasure of stepping on chewing gum in a parking lot. Cleaning up the sticky mess might become easier, thanks to a new gum created by U.K.-based Revolymer. The gum easily comes off roads, shoes, and hair, and it barely sticks at all to some surfaces.The company has conducted extensive trials on the ease of cleaning up the gum and has done independent taste tests. Revolymer’s CEO, Roger Pettman, says that the company is now looking to get a U.S. Food and Drug Administration safety affirmation. If all goes as planned, Revolymer will launch the gum in three different flavors–mint, fruit, and lemon–next year.

About 600,000 metric tons of chewing gum are manufactured in the world every year, Pettman says. A large percent of that ends up on streets and pavements, becoming a pollution issue. “There is no great way to remove it,” says Pettman. Every year, London spends an estimated two million pounds, or more than four million dollars, to clean gum from subway trains and stations, according to a 2005 report by the London city council. The United Kingdom’s Department of Environment, Food and Rural Affairs has launched a national campaign to tackle gum litter, while Singapore has enacted the famous chewing-gum ban.

Revolymer’s product has a formulation unlike most commercially available brands. The main ingredient in most chewing gums is a gum base: a mix of synthetic petroleum-derived polymers, natural latex, resins, and waxes. All of these components are hydrophobic–they stay away from water–which means that they are oil loving, says Pettman. This is the reason that gum traditionally sticks to the grease and grime on sidewalks. The Revolymer gum base has polymers with a hydrophobic part that’s wrapped inside a hydrophilic, or water-attracting, part. So even though the gum sticks to a surface, a film of water can form around it so that it easily washes away with water.

The new gum performed well in tests. When Revolymer researchers stuck it on sidewalks in U.K. towns, rainwater or street cleaning would wash it off within 24 hours. Most commercial gums, on the other hand, remained stuck and were difficult to remove. Tests also showed that when the new gum was stirred into water, it disintegrated completely in eight weeks, which means it could degrade once it goes into a drain.

The gum also did well in blind taste tests, Pettman says, with testers saying that it tasted just as good as leading brands. The texture, though, is slightly softer, he says, because the hydrophilic polymer interacts with saliva.

So far, no other company has developed a nonsticky, degradable chewing gum. Soo-Yeun Lee, a food-science professor at the University of Illinois at Urbana-Champaign, has developed a natural, biodegradable chewing gum that uses corn proteins instead of synthetic polymers. Her work was published in 2004 but is not ongoing.

Lee says that leading gum manufacturer Wrigley has a patent on a similar corn-based gum. According to the London city-council report, Wrigley has spent more than $10 million on research to find a biodegradable product but has yet to report success.

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Diploma In Plastics From St. Clair College – Ontario

 source: http://www.stclaircollege.ca/fcem/fcem-3-6.html

Plastics Engineering Technology (Co-Op) (T913)

Location: Windsor

Plastics Engineering Technology includes the theory and practical applications of various aspects of plastic parts production from design through to mass production and testing. Topics include properties of plastics and composites, product design, mould design, plastics processing, cost estimating, prototyping and project management. It is a three year diploma program with an optional fourth year leading to a technology degree currently under development.

KEY PROGRAM FEATURES

  • Optional Co-op Work Terms
  • Transfer Agreements with Universities
  • First Year is Common with T826, T841 and T842 providing flexibility to transfer between these programs at the start of semester 3 without loss of credit

PERSONAL CHARACTERISTICS:

  • Interested in concepts and theories
  • Mechanical Aptitude
  • Good communication and interpersonal skills
  • Ability to receive, understand and give instruction
  • Good work habits

EMPLOYMENT OPPORTUNITIES
Excellent employment opportunities exist for graduates of Mechanical Engineering Technology – Plastics. This program was designed to reflect the current requirements of the plastics industry and will prepare students for diverse and financially rewarding positions in plastic product design, mould design, production supervision and project management.

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Thermoplastics For Aircraft Interiors

source: http://www.compositesworld.com/hpc/issues/2007/September/112011

Thermoplastics for aircraft interiors

By Staff | September 2007

GE Plastics (Pittsfield, Mass.) has launched three new resins designed for use in aircraft interiors. Noryl LS6010 is a polyphenylene ether (PPE) that has a specific gravity of 1.1, which is one of the lowest available for thermoplastics used in aerospace. It also features low smoke, good durability and nonhalogenated flame retardance (FR). Applications include rub strips and seat track covers, for which low smoke propagation is mandated. Lexan FST9705 is a polycarbonate (PC) copolymer said to be suitable for personal service units, window reveals and bezels, and offers full flame/smoke/toxicity compliance, including OSU 55/55 heat-release performance. Flame-retardant Ultem 9085 is a polyetherimide (PEI) resin that is said to offer better flow and ductility than GE’s Ultem 9075 resin and can reduce part weight by 5 to 15 percent via thinner walls. The material also provides the highest modulus of any Ultem resin grade. Potential applications include decompression grilles, window reveals and personal service units. 1197

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New Laser Marking Technology For Plastics

source: http://www.azom.com/details.asp?newsID=10146

The Sabreen Group, Inc. announces its Patent Pending VectorJet™ Laser Marking Technology that achieves unprecedented “dark-on-light” contrast, line edge detail, and marking speed on Acetals, and many more plastics that have traditionally been difficult, if not impossible, to laser mark. Utilizing this breakthrough technology, true “dark-on-light” marking of Acetals can be successfully used in a far broader range of applications, even those requiring reliable machine vision and micro-marking for product security and traceability.

This quantum leap in laser marking technology will assure consistent and permanent markings on products that require exacting identification and traceability in demanding markets such as aerospace, automotive, electronics, medical, and industrial applications.

Significance of the Laser Marking Technology:
Copolymer and homopolymer Acetals (POM), and other chemically inert thermoplastics, possess highly desirable performance properties for a broad range of industries and applications including automotive and medical. Historically, expensive ink printing and surface pretreatments fail to provide long-term field product identification or safety warning information, particularly when exposed to chemicals and environmental forces. Non-contact, indelible laser marking is a preferred process in part because of its capability to code variable, sequential and unique part information.

Since the mid-1990’s some manufacturers of Acetals, as well as compounding and colorant companies, have sold a lasermarkable grade which can yield “light” colored contrast on dark colored substrates and tone-on-tone. However, the majority of Acetal products are not dark, rather white or light colored substrates (typically pigmented with TiO2). Traditional Nd: YAG laser marking incorporating high levels of laser doping additives produce less than desired detailed contrast quality. To work around printing/marking limitations, designers are often forced to select alternative resins that can be more expensive and possess less than ideal performance properties.

VectorJet™ Laser Marking Technology achieves breakthrough “dark” marking contrast on “light” colored acetal products, as well as “light” contrast on “dark” products. The result is a far reaching laser marking technology that eliminates virtually all restrictions when selecting product and marking color, reduces costs relative to conventional marking lasers, and enables reliable machine vision readability and micro-marking. “We are excited to continue the advancements in plastics laser marking which will benefit industry in manufacturing the best products at lower costs while incorporating six-sigma marking processes” said Scott Sabreen, Founder & President.

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Bayer Makrolon: Investing In A Sustainable Future

source: http://www.happynews.com/news/9212007/bayer-materialscience-continues-commitment-sustainable-development.htm 

Bayer MaterialScience Continues Commitment to Sustainable Development


(Business Wire) :: The north wall of the 2005 Carnegie Mellon Solar Decathlon competition house (pictured) uses translucent polycarbonate siding provided by Bayer MaterialScience.

Makrolon(R) Polycarbonate and Other Bayer Materials Featured in Carnegie Mellon University’s Solar Decathlon Competition House

Bayer MaterialScience LLC (BMS) continues its commitment to sustainable development education and research by again participating as a sponsor of Carnegie Mellon University’s 2007 Solar Decathlon competition house. Progress on the latest Carnegie Mellon decathlon project was showcased yesterday afternoon at an event at Pittsburgh’s “Construction Junction,” the construction site for the university’s 2007 Solar Decathlon competition house.

“We are proud to be continuing our involvement with this important project through our sponsorship of another Carnegie Mellon Solar Decathlon house,” said Mark Witman, Director, Future Business, Industry Innovations, BMS LLC. “The 2007 project makes extensive use of Bayer MaterialScience’s Makrolon(R) polycarbonate. Makrolon is the backbone of Bayer’s broad product portfolio and a material that has been an important part of the innovative design and environmentally conscious construction of the Solar Decathlon house.”

BMS supplied the translucent polycarbonate siding for the north wall of the 2005 Carnegie Mellon Solar Decathlon house. The Makrolon polycarbonate material will also be used in a light diffusing insulating roof panel for the 2007 competition house. It is the same high-tech and energy-efficient polycarbonate sheet that BMS is supplying for the roofing material for sporting arenas at China’s 2008 Olympic Games.

The Carnegie Mellon team has also chosen Makrolon Multiwall IQ-Relax reflective polycarbonate sheet for windows in the house. This insulating product reflects infrared energy – and consequently heat – by virtue of its unique composition and multiwall structure. The sheets function as panes in concept windows in the 2007 structure and provide high light diffusion and extreme heat reduction that result in increased energy efficiency. Bayer MaterialScience collaborated with TRACO, a southwestern Pennsylvania-based commercial and residential window manufacturer, to design the concept windows.

BaySystems North America LLC supplied BaySeal(TM) sprayed foam insulation for sealing and insulating portions of the building envelope of the competition house. BaySeal spray polyurethane foam is a highly efficient insulating material, and homeowners have reported energy savings of 50 percent or more over conventional insulation systems like fiberglass. It also serves to reduce air movement in and around the wall, thus cutting down on cold air drafts by achieving a moisture and thermal seal. The 2-pound, closed-cell BaySeal spray foam insulation was applied to the structure by InsulRight of North Versailles, Pa.

Other BMS materials are also featured in the 2007 competition house, including Baydur(R) polyurethane insulating foam raw material that was used by CENTRIA Architectural Systems to manufacture the polyurethane/metal composite panels used for the building exterior. VIVAK(R) co polyester sheet, supplied by Bayer subsidiary Sheffield Plastics Inc., is used by 3form, Inc., to produce its decorative architectural panels that are being used for a variety of interior design and architectural applications.

The Solar Decathlon, sponsored by the United States Department of Energy, is a two-year process where 20 collegiate teams from across the United States, Europe and Canada compete to design, build and operate the most attractive and energy-efficient solar-powered home. In October the teams will transport their solar houses to the National Mall in Washington, D.C., where they will form a solar village. The schools will then compete in 10 contests to determine an overall winner. Using only energy from the sun, the competing structures will generate enough electricity to run a modern household.

“At Bayer, we are committed to the principles of sustainable development and strive to make a lasting and positive contribution to sustainable and environmentally compatible construction,” said Witman. “As an ongoing part of Carnegie Mellon University’s Solar Decathlon Project, we continue to demonstrate our dedication to treating the planet responsibly while offering products that can be used to generate creative solutions to address global concerns about the environment.”

The design of the 800-square-foot 2007 Carnegie Mellon solar house is based on the “plug and play” construction concept, which demonstrates the ways in which basic building blocks can be reconfigured to suit multiple contexts. The design is also multi-level to increase useable floor area for a given footprint. Construction of the 2007 house concludes this month at Construction Junction in Pittsburgh.

“We appreciate Bayer’s ongoing involvement and support of this project,” said Steve Lee, architecture faculty advisor to the Carnegie Mellon team. “We believe that the 2007 solar house, with the use of Makrolon polycarbonate resin, will be another successful example of innovative and sustainable urban design.”

Following the Solar Decathlon competition Oct. 12-20 in

Washington, D.C., the 2007 Carnegie Mellon solar house will become a permanent addition to the facilities in Powdermill Nature Reserve, located outside Pittsburgh in Westmoreland County. Powdermill Nature Reserve is an outdoor educational center and biological field station affiliated with the Carnegie Museum of Natural History.

Bayer MaterialScience LLC is one of the leading producers of polymers and high-performance plastics in North America and is part of the global Bayer MaterialScience business with nearly 14,900 employees at 30 sites around the world and 2006 sales of 10.2 billion euros from continuing operations. Our innovative developments in coatings, adhesive and sealant raw materials, polycarbonates, polyurethanes and thermoplastic urethane elastomers enhance the design and functionality of products in a wide variety of markets, including the automotive, construction, electrical and electronics, household and medical industries, and the sports and leisure fields. Our inorganic basic chemicals unit produces chlorine and related essential products for the chemicals industry. Let us give life to your vision. Bayer MaterialScience – Where VisionWorks.

Bayer Corporation, headquartered in Pittsburgh, is a subsidiary of Bayer AG, an international health care, nutrition and innovative materials group based in Leverkusen, Germany. In North America, Bayer had 2006 net sales of 7.8 billion euros and employed 17,200 at year end. Bayer’s three subgroups, Bayer HealthCare, Bayer CropScience and Bayer MaterialScience, improve people’s lives through a broad range of essential products that help diagnose, prevent and treat diseases; protect crops and enhance yields; and advance automobile safety and durability. Bayer AG stock is a component of the DAX and is listed on the New York Stock Exchange (ticker symbol: BAY).

This news release contains forward-looking statements based on current assumptions and forecasts made by Bayer Group management. Various known and unknown risks, uncertainties and other factors could lead to material differences between the actual future results, financial situation, development or performance of the company and the estimates given here. These factors include those discussed in our public reports filed with the Frankfurt Stock Exchange and with the U.S. Securities and Exchange Commission (including our Form 20-F). The company assumes no liability whatsoever to update these forward-looking statements or to conform them to future events or developments.

VIVAK(R) is a registered trademark of Sheffield Plastics, Inc.
BaySeal(TM) is a registered trademark of BaySystems North America LLC

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Learning To Live With Plastic

 source: http://economictimes.indiatimes.com/News/News_By_Industry/Indl_Goods__Svs/Paper__Wood__Glass_Plastic_Marbles/Plastics_for_Environment__Sustainable_Development/articleshow/2388151.cms

Plastics for Environment & Sustainable Development

21 Sep, 2007, 0126 hrs IST, TNN

Plastics are ubiquitous in today’s world and have contributed to the improvement in the quality of life. There is no human activity where plastics do not play a key role, from clothing to shelter, from transportation to communication and from entertainment to health care.

Plastics, because of its many attractive properties, such as lightweight, high strength and ease of processing, meet a large share of the material needs of man. From practically zero in the fifties, humankind today consumes close to one hundred and seventy five million tonnes of plastics. We truly live in a ‘Plastics Age’. Our daily lives would be very much poorer without plastics, rubber and synthetic fibers.

Nature has produced ‘plastic’-like materials for centuries. Silk and cellulose are example of natural polymers. Reference to Shellac, a thermoplastic can be found even in Mahabharatha!

Plastics are employed in myriad applications where they actually conserve natural resources. For example, asceptic packaging of food in barrier packaging films will render refrigeration unnecessary, saving capital and energy. Edible oils and milk are packaged in flexible packages eliminating the use of tin and glass containers.

Rigid HDPE barrels are used for bulk chemical storage instead of steel drums. Apart from conserving natural resources, use of plastics in these applications saves transportation fuel as plastics are substantially lighter than tin, glass or steel. This specific characteristic of plastics is especially made use of in industries like the automobile & aviation, resulting in fuel efficiency.

Modern buildings and constructions use plastic doors, windows, floor and wall coverings instead of wooden ones, ultimately saving trees. In Agriculture, plastics are used in irrigation pipes, tubes, hoses to better the micro-irrigation system as well as in greenhouses, mulching films, increasing productivity.

The health care sector uses plastics in blood bags, tubing, heart catheters, IV fluid bags, disposable products (gowns, masks, syringes) because it is both hygienic as well as easier to handle than other materials. Lifestyle products like electrical appliances, furniture, luggage, toys are also made of plastic for similar reasons.

Safe drinking water packaged in PET bottles is a very common sight now-a-days. They provide confidence to the consumer on the quality of water and help reduce waterborne diseases.

The fact that plastics are made from hydrocarbons derived from petroleum, which is non-renewable, has raised questions concerning its sustainability. Nevertheless, the consumption of petroleum hydrocarbon for the production of plastics is less than 5%, the balance being consumed as fuels and energy source. Consequently, concerns about sustainability of plastic materials is somewhat exaggerated.

On the contrary, processing of many natural materials (glass, paper, wood, metals) consume far more energy derived from fossil fuel. Additionally, research and development work currently in progress globally will provide future opportunities to make some of the plastics from biomass and other renewable resources.

It is fair to say that plastics replace several natural materials, which are either scarce, consume more energy for processing or cause damage to the eco-systems during their production. Thus, use of plastics makes a positive contribution to the sustainability of earth’s resources in myriad ways.

Another issue that is often discussed is whether because of their non-biodegradability, plastics will cause damage to our eco systems. The signature of all natural materials made by biological processes is that they are biodegradable and bio-assimilable. The long life and desirability of plastics, which have made them a material of choice for many applications is seemingly a disadvantage when it comes to their disposal. However, when handled properly, plastics do little damage to our environment.

Plastics have the advantage that they can be easily reprocessed and recycled. In some cases, one can recover even the raw materials that were originally used in their manufacture. Plastics offer the unique advantage that one can recover the fuel value contained in the hydrocarbon polymer after its use.

The overall eco-friendliness of plastics becomes apparent when one evaluates the total ‘life cycle’, namely, an analysis of raw materials, energy, effluents, methods of disposal, etc., of a material from its origin to its final disposal.

It is believed that established scientific data will set to rest any lingering doubts about the sustainability of plastics as materials or their adverse impact on our environment and will lead to more enlightened discussion on the role of plastics in the armoury of materials used by men.

Courtesy: Indian Centre for Plastics in the Environment

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Cool Light Poles Made With Acrylic

Light poles from Selux Australia

source: http://www.infolink.com.au/articles/Light-poles-from-Selux-Australia_z74520.htm

Selux Hollow Light Guides

Modern light poles from Selux Australia offer architects tools to create an unique identity.

Selux Hollow Light Guides consist of a special PMMA Acrylic Light Pipe, which is illuminated internally by a 150 watt Metal Halide lamp.

Designed with internal reflectors for uniformity, a 150w metal halide lamp per luminaire is used in order for the light to be carried through the tube resulting in the luminescence effect.

The Selux Hollow Light Guides feature a solid round metal tube base of Cast aluminium or galvanised steel with an access door flap IP 65. A special internal stainless steel support rod allows for the system to be mounted at angles of up to 15 degrees.

Cox Architects used the Selux Hollow Light Guide to form a striking and functional lighting system leading into the main entrance of The Perth Convention and Exhibition Centre. Using a combination of 10-degree and 15-degree offset, the Selux Hollow Light Guide matches the scale and modern nature of the architecture.

Zaha Hadid Architects and the Strassburg car park uses Selux Hollow Light Guides set at 15 degrees.

20-Sep-2007

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Four Story Tall Wine Rack Made From Acrylic

 source: http://www.plasticsmag.com/features.asp?fIssue=Jan/Feb-01&aid=3115

World’s Tallest Wine Rack

Las Vegas Restaurant Features Four-story Acrylic Wine Tower

It’s a four-story acrylic “cellar in the sky”. Clad in black bodysuits and rock climbing gear, “Wine Angels” scale the 42-foot structure to collect wine for discriminating patrons. Where else but Las Vegas – a city with eight million annual hotel guests and a reputation for over-the-top interior design. When the Mandalay Bay Resort & Casino opened its 3,700-room resort to guests, it took its interior to new heights by installing the tallest wine rack in the world within its Vegas version of New York chef Charlie Palmer’s Aureole restaurant.

Patrons enter the restaurant via a catwalk-style bridge and stairway that spirals around the wine tower, which sits atop the 64-foot square room center, making it the focal point of the restaurant. In addition to its functionality of housing wine, the rack acts as an entertainment piece and adds to the rooms ambiance.

This monumental structure must maintain its stunning appearance and stability, which accommodates the weight of approximately 16,000 bottles plus the “Wine Angels”, a true challenge for fabricator, Perry Youssefy, president of Crystal Craft (La Verne, CA).

“We needed to use a dense cell-cast acrylic material for this tremendous structure,” explained Youssefy. “We chose CYRO Industries’ ACRYLITE® GP acrylic sheet for its lightweight, high-impact strength, excellent optical clarity, and its ability to withstand expansion and contraction due to the refrigerated sections of the tower.”

Chilled To Perfection

The white wine sections of the tower must be kept at 40° F. To allow for cool air circulation and to keep the temperature continuous, 2 1/2″ holes were drilled into the refrigerated inner core at the back of the white wine cavities. The red wine section backs remained closed.

“This material is able to handle expansion and contraction due to temperature changes,” said Youssefy. “Our fabrication technique allowed enough room for this purpose, otherwise the piece would fall apart.”

Initially built in four towers, the wine rack was freighted to the assembly site. Each tower measured 12″D x 8′W x 42′H. Crystal Craft used 1/2″ thick acrylic sheet for five to ten shelf modules, which hold anywhere from five bottles to a case of wine. To secure the structure and hold modules together (some as large as 8′ x 11′), stainless steel screws and inserts were used.

“Cementing was a pivotal issue because poor bonding causes the structure to sag or fall apart. Plus, proper cementing protects the structure from moisture penetration,” added Youssefy. “ACRYLITE GP sheet responds positively to bonding and gluing, 99.9 percent of the time.”

Heavy cement that contained both resin and hardening components, was used. “It is heavier than liquid cement and fills up all cavities. It must be machined, sanded, and polished. Ultimately, it becomes extremely strong, remaining stable in terms of expansion and contraction, just like the acrylic,” said Youssefy.

Neon lighting was used to illuminate the inside of the tower. To accommodate this, translucent white acrylic sheet was used to diffuse the light.

The wine cavities were notched together, horizontally, inside the modules. This was necessary to avoid one section pushing too hard against another, which could cause deformation or crazing. The design also had to compensate for the potential weight of a full rack, 16,000 bottles.

“We made these horizontal shelves with negative/positive notches, and depending on the length and size of the module, a gap of 1/32″ to 1/16″ was implemented. Each had to be perfectly notched together or the glue joints wouldn’t hold,” explained Youssefy.

The Finished Project

Despite a tough challenge and tight timeframe, the Mandalay Bay debuted its “cellar in the sky”, on time, after six weeks of 22-hour workdays.

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Make Your Own Plastic

source: http://www.spartechsoftware.com/reeko/Experiments/ExpMakingPlastic.htm

Making homemade plasticYep, we’re surrounded by plastic. Sit right there and look around the room and see if you can spot something made of plastic. See, I told you so. The keys on your keyboard are made of plastic. The mouse you’ve got your hand resting on is made of plastic. Even parts of the monitor you’re looking at right now is made of plastic (yikes… Reeko, I don’t know how you know all these things but stop it – it’s giving me the creeps).

These plastics can be either natural plastics which are made of materials such as wax or natural rubber, or they can be synthetic plastics which are made from polyethylene or nylon. Most plastic is made of petroleum oil. The type of plastic we’re fixing to make is of the natural type.

  1. Have an adult slowly warm 1/2 cup of heavy cream (or milk).
  2. When it begins simmering, stir in a few spoonfuls of vinegar (lemon juice will also work).
  3. Continue adding spoonfuls of vinegar and stirring until it begins to gel.
  4. Now let the it cool.
  5. Next, wash the rubbery stuff with water to clean it off. You’ll have little plastic ‘curds’.

Voila! You have plastic! If you want to really have some fun with it, take it to Dad and tell him you’ve been sitting out in the garage watching this stuff drip off from under the car for about an hour now. Note: if he begins gathering up tools, it might be a good time to level with him…

The acid - a sour tasting, corrosive substance – the opposite of a base substance. Acidic solutions will turn a litmus red - in the vinegar reacts with the casein in the milk making the plastic. In practice, this type of plastic would be much too expensive for household use. Oil-based plastics are much cheaper since the raw materials needed are much easier to come by. But alas, even oil is a resource that will someday run out. Scientists know this and are hard at work searching for new ways to make plastic. Maybe you could be the one to find the answer…

Parent’s Note. Plastics are characterized by high strength-to-density ratios, excellent thermal and electrical insulation properties, and good resistance to acids, alkalis (a substance having marked basic properties (i.e. substance with properties of a base), and solvents. The giant molecules  ( one of the basic units of matter. It is the smallest particle into which a substance can be divided and still have he chemical identity of the original substance.) of which they consist may be linear, branched, or cross-linked, depending on the plastic. Linear and branched molecules are thermoplastic (soften when heated), whereas cross-linked molecules are thermosetting (harden when heated).

The development of plastics began about 1860, after Phelan and Collander, a United States firm manufacturing billiard and pool balls, offered a prize of $10,000 for a satisfactory substitute for natural ivory. One of those who tried to win this prize was U.S. inventor John Wesley Hyatt. Hyatt developed a method of pressure-working pyroxylin, a cellulose nitrate of low nitration that had been plasticized with camphor and a minimum of alcohol solvent. Although Hyatt did not win the prize, his product, patented under the trademark Celluloid, was used in the manufacture of objects ranging from dental plates to men’s collars. Despite its flammability and liability to deterioration when exposed to light, Celluloid achieved a notable commercial success.

Other plastics were introduced gradually over the next few decades. Among them were the first totally synthetic plastics: the family of phenol-formaldehyde resins developed by the Belgian-American chemist Leo Hendrik Baekeland about 1906 and sold under the trademark Bakelite. Other plastics introduced during this period include modified natural polymers such as rayon, made from cellulose products.

 

Sources:
Encarta 98
Museum of Life and Science, Durham, North Carolina

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