Because silicones can withstand astonishing stress and temperature extremes, they are used in many aspects of aircraft and spacecraft assembly and maintenance. Adhesives and sealants are used to seal and protect the following from the elements: doors, windows, wings, fuel tanks, hydraulic switches, overhead bins, wing edges, leading gear electrical devices, vent ducts, engine gaskets, electrical wires and black boxes. Silicones deliver the strength, adhesion and durability needed in high-performance automobiles, ocean vessels and spacecraft. Exteriors are more resistant to heat and cold, rain, wind, salt, abrasion, ultraviolet radiation and chemicals because of silicone adhesives and coatings used to extend theservice life of cars, boats and planes. Joints last longer and overall maintenance and repair is lesscostly. Silicone coatings ensure that airbags don’t deteriorate over time and that they remain gas-tightand heat-resistant under the pressure from rapid inflation and other extreme conditions, such as fire.Silicone coatings are also used as release agents to allow tire manufacturers to get the tires out oftheir manufacturing molds and silicone rubber is used in many tires to provide long wear life andsuperior traction.
Read moreMany experts and authorities consider silicone completely safe for food use. For example Health Canada states: "There are no known health hazards associated with use of silicone cookware. Silicone rubber does not react with food or beverages, or produce any hazardous fumes." Scientific American reports that in 1979 the US Food and Drug Administration determined silicon dioxides—the raw material for silicone products—were safe for food-grade applications. However, the first silicone cookware only appeared a decade later (e.g., spatulas) and no follow-up studies were done to assess whether silicone cookware leaches anything potentially harmful. The fact is, there has not been a lot of research done to date on the health effects of silicone.Nonetheless, our own research and review of peer-reviewed scientific studies that have been done indicates we should begin to be cautious about silicone. Here are some highlights: Silicones are not completely inert or chemically unreactive and can release toxic chemicals. They can leach certain synthetic chemicals at low levels, and the leaching is increased with fatty substances, such as oils. Evidence of contamination from silicone was found in wine and edible oil foods. Materials such as aluminium, platinum, magnesium and calcium were found to have leached into food when testing was carried out on silicone bakeware. Fluid silicone studies indicated release of siloxanes, one of which - cylcopentasiloxane - is considered toxic and persistent. This siloxane, also known as D5, is used as a softener in cosmetics, and according to the U.S. Environmental Protection Agency may also be carcinogenic. (2005 Report commissioned by the United Kingdom Food Standards Agency: Chemical migration from silicones used in connection with food-contact materials and articles) Silicone tubing commonly used for medical applications has been shown to leach several chemicals, including dioctyl phthalate (DOP). (2006 Study in International Journal of Pharmaceutics: Extractables/leachables from plastic tubing used in product manufacturing) Silicone intravenous devices have been shown to leach silicone and cause local inflammation. (1999 Study in Archives of Disease in Childhood: Plastic migration from implanted central venous access devices) Silicones likely not completely inert and may cause local inflammation. as suggested in this study on the breakdown of silicone joint implants. (1985 Study in Oral Surgery, Oral Medicine, Oral Pathology: Silicone-induced foreign body reaction and lymphadenopathy after temporomandibular joint arthroplasty) Our Suggestion: Relatively safe. But silicone is not as inert, stable and chemically unreactive as many claim. Use with caution, and if you can find an alternative, use it. As you can see from our product line, we carry a number of items that contain silicone, usually in the form of seals or gaskets. Silicone has become a standard high quality seal for products requiring a airtight watertight seal, and a suitable alternative has not yet become available. For now, we are comfortable continuing to carry products that have high quality, food grade silicone parts. We balance the toxicity information stated above with the knowledge that silicone is a high quality, relatively stable material, and leaching of chemicals from other plastics is of much greater concern. We feel uneasy about silicone cookware. While silicone is durable and has a high temperature resistance, it makes us queasy to be heating food to very high temperatures in a material like silicone which has now been shown to leach and is not completely inert and stable. If you are going to use silicone, be sure it is high quality, food grade silicone and does not contain any fillers. To test a product for fillers you can pinch and twist a flat surface of it to see if any white shows through. If so, a filler likely has been used. As a result, the product may not be uniformly heat resistant and may impart an odor to food. But most importantly, you will have no idea what the filler is and it may leach unknown chemicals into the food. For all you know, the filler may be a silicone of low quality or not silicone at all.
Read moreIS SILICONE A PLASTIC? Good question. Here are some others... Is it a rubber? Is it natural? Is it synthetic? What the heck is it? And most importantly: Is it safe? Description and Typical Use: What is silicone? Technically, silicone is considered part of the rubber family. But, if you define plastics widely, as we do, silicone is something of a hybrid between a synthetic rubber and a synthetic plastic polymer. Silicone can be used to make malleable rubber-like items, hard resins, and spreadable fluids. We treat silicone as a plastic like any other, given that it has many plastic-like properties: flexibility, malleability, clarity, temperature resistance, water resistance. Like plastic, it can be shaped or formed and softened or hardened into practically anything. But it is a unique plastic because it is much more temperature resistant and durable than most plastics and has a low reactivity with chemicals. And while water resistant, it is also highly gas permeable, making it useful for medical or industrial applications where air flow is required. It's also easy-to-clean, non-stick, and non-staining, making it popular for cookware and kitchen utensils. Thus, while most plastics have a polymer backbone of hydrogen and carbon, silicones have a backbone made of silicon and oxygen, and hydrocarbon side groups - all of which gives them plastic-like characteristics. Silicone is often used for baby nipples, cookware, bakeware, utensils, and toys. Silicones are also used for insulation, sealants, adhesives, lubricants, gaskets, filters, medical applications (e.g., tubing), casing for electrical components.
Read more-- Silicones Are Extremely Versatile Silicones are used across some of the most strenuous and yet some of the most sensitive applications. They add "industrial" to the "strength" of coatings, sealants and joints in skyscrapers, bridges, highways and ocean vessels. Used in personal care products and health care, they make lotions, topical medications and skin adhesives easy to apply and less irritating. Regardless of the application, silicones' wide-ranging properties make them a key ingredient in thousands of consumer and industrial materials. Silicones' versatility stems from their performance and protective qualities. -- Performance Silicones can be made in a range of forms, including: solids, resins, rubbers and fluids. Silicones have a wide range of material properties, such as: Adhering or releasing Hard or soft Rigid or flexible Absorbent or water repellent Conductive or insulating Foaming or defoaming -- Protection Silicones in clothing, outerwear, shoes and personal care products protect people from heat, cold, wetness, electricity and UV damage. Silicones used in industrial applications protect equipment and possessions from: Water damage UV damage Extreme heat Extreme cold Climate changes Corrosion Chemicals and oils UV damage Microbes And, silicones retain these properties over time so materials are less susceptible to damage from weathering, aging, temperature or climate fluctuations and normal wear and tear.
Read morehttp://www.culinarylore.com/tools:5-advantages-of-silicone-baking-sheets Have you heardof silicone baking mats? These are silicone impregnated fiberglass sheets thatcan be placed on a baking sheet to replace parchment paper or aluminum foil.But that is not all they replace. They are not new. Professional bakers havebeen using them for years. Today, they are becoming a common piece of cookwareat home. Why are they better than regular baking sheets? Why should you usethem? There are several advantages to using silicone baking sheets over regularmetal baking sheets. 1. They ReplaceParchment Paper or Aluminum Foil Parchment paper issilicone impregnated paper. When you use it to line baking trays to bakecookies and other baked goods on, you don't need any grease and there is nosticking. Siliconebaking mats replacerolls of parchment paper, and can be used over and over. Saving money andcausing your kitchen to be a little bit greener. They will also stand in nicelyat times when you would normally use aluminum foil liners. Not only do theyseem to have almost magical non-sticking qualities, they can be used up to 2000times. They are made to fit into rimmed baking sheets or to place on flatcookie sheets and they can withstand temperatures of up to 480°F but also betaken straight from the freezer to the oven. Another advantage over silicone baking sheetsover metal baking sheets is that they can be used in the microwave! Check tomake sure your particular mat is safe for this use, though. 2. Easy toClean Since nothing sticks to silicone baking mats, they are very easy to clean. A quick soap and water cleanup is all you need, there is no scrubbing, soaking, or other cleaning hassle.If you are baking something that is messy, with a lot of sugar or butter, for instance, you'll love them. They are perfect for turnovers or pocket pies. You do need to lay them flat, or hang them, to dry, though. They resist staining and odors. 3. You Need Less Cookie Sheets Normally, if you wanted to make many batches of cookies, you'd be laying out your cookies on one baking tray while another one baked in the oven. You need at least two cookie sheets for that, and if you are baking a huge batch with two ovens, fore example,you'd need up to four. With silicone baking sheets, you only need one or two metal baking trays (depending on the number of ovens you have going). Several silicone mats can be used to line one or two cookie sheets. You just lay out your cookies on a mat while a batch is cooking on another mat, and when they are done, you slide off one mat as slide on the new one. Of course, they take up a lot less storage space, and they can even be rolled up for storage. 4. There Is Less Burning or Browning Silicone baking mats have the same advantage that parchment paper can give you. There tends to be less browning on the bottom of baked goods, and less potential for burning. Silicone mats are especially good for baking fish on, as you won't have to worry about the fish sticking and tearing when you lift it off the mat. As well, if you are using any sort of sticky glaze, you'll appreciate the non-stick surface of the mat. 5. They Are Good Also Good For Kneading Dough On A regular silicone baking mat can be used to knead dough on. It's great for kneading pizza, bread, or even pie dough. The dough doesn't stick to the mat and, although you still need to use flour to incorporate into the dough, you don't have t o worry as much about sticky dough clinging to the kneading surface. As well, silicone pastry mats are available with measurements, to use for rolling out pie and other pastry dough. Professional bakers use silicone mats for working with fondant,chocolate, sugars, and other sticky things.
Read morehttps://www.masterbond.com/techtips/why-use-silicone-adhesive With the vast supply of adhesivesavailable, silicone adhesives stand out from the crowd. Based on elastomerictechnology, silicone adhesives offer unparalleled flexibility and exceptionallyhigh heat resistance, making them suitable for a wide range of applications inthe electrical, electronic, automotive, aerospace and construction industries. Silicone adhesives are available in varieties includingtwo component systems that require the addition of a curing agent, onecomponent systems that cure simply by the moisture in the air, UV or EBradiation curing adhesives that cure with exposure to a UV light or pressuresensitive versions that adhere to surfaces with very slight contact pressure. In general, users can count on siliconeadhesives to produce bonds that can withstand high temperatures (in some casesup to 600°F), remain flexible even after curing and resist chemicals includingwater. However, each type of silicone adhesive also offers its own set ofadvantages. One component systems emphasize convenience, with no mixingrequired and the ability to cure at room temperature. While a two componentsystem does require mixing, it can cure in thicker sections than one partsystems, which might be necessary for certain applications. UV or radiationcured silicone adhesives use UV lamps or an electron beam to cure withoutadditional heating or excessive heat generation. Silicone adhesives boast excellent electricalproperties and can be formulated to be insulative with a high dielectricstrength, or conversely electrically conductive. Many one part siliconeadhesives release a corrosive entity, such as acetic acid, but there arespecial formulations that are totally non-corrosive and can be used withelectronics. These are often used as a conformal coating for electronic circuitboards. Silicone systems are also used for sealing cables and sensors in bothappliances and electronics. Silicone adhesive applications run the gamut fromhousehold tasks to bonding and sealing in outer space. Their unique properties makethem ideal for a wide variety of applications ranging from the assembly ofcomponents for commercial printers to bonding medical catheters. With theirability to resist water and other chemicals, silicone systems are used forsealing gaskets and engines in the transportation industry. They are also usedfor potting and heat sink attachment in electronic applications.
Read moreThis article is about comparison between porcelain and silicone rubber for use as outdoor insulation on high voltage bushings. The contents include Hydrophobicity, Leakage currents, Lightweight, Maintenance free, etc. Comparison between porcelain and silicone rubber bushings: Introduction: Silicone rubber has been in use as outdoor insulation for suspension insulators and in other applications for more than 25 years. Today, silicone rubber together with EP- rubbers is the most used polymeric materials for medium and high voltage outdoor insulation. Below follows a list with the most important properties for outdoor insulation and a short comparison between the characteristics of silicone rubber and porcelain both as materials and as an integral part of the bushing. Hydrophobicity: The surface of SIR maintains a high level of hydrophobicity even during severe environmental conditions. If the hydrophobicity of the surface is decreased, the surface will recover its hydrophobic properties in less than 12 hours since the SIR continuously emits molecules of silicone oil to the surface. The layer of silicone oil is only a few molecules thick and provides the hydrophobic properties of the surface. The hydrophobicity of porcelain on the other hand is reduced already after a few days with medium severe pollution levels and will not recover unless the surface is cleaned. The design criteria for porcelain insulators according to standards are 31 mm/ kV at severe pollution levels. In order to fulfill the standard requirements, the same design criteria for specific creepage distance for SIR insulators as for porcelain is used which provides an even more robust design regarding the limitation of leakage currents. Leakage currents: Thanks to the improved performance during and after severe environmental conditions, the leakage current level along the insulator is very low compared to porcelain. A typical value for porcelain is 10 mA and for silicone < 1 mA. This property also reduces the risk for flash-overs and thus increases the reliability of the product and eliminates the disturbances in the power grid resulting from such events. Lightweight: The density of SIR is 1530 kg/m3 and 2500 kg/m3 of porcelain. The electrical insulation inside the SIR is made of resin impregnated paper. The high mechanical strength of the insulation material supports the SIR, which need to be just 5 mm thick with the exception of the sheds. Thus the weight of the GSA bushings is reduced to approximately half of its equivalent oil impregnated bushings with porcelain as outdoor insulation. With a more light weight design, the ability to withstand earthquakes is increased as well. Maintenance free: The need for cleaning the insulator is almost eliminated when using SIR. Porcelain on the other hand might have to be cleaned more often in medium polluted areas as well. SIR may need to be cleaned but only in extreme environmental conditions. Non-shattering material: The SIR material has a non shattering failure mode if subjected to vandalism, mechanical shocks etc. The GSA bushings with SIR insulators are well suited for applications where vandalism by for example stone or brick throwing can be expected. The risk for transport damage is almost eliminated as well. The safety of personnel is increased due to the non shattering material in the case of an unexpected failure on site. Self extinguishing: Silicone rubber is proved to be self extinguishing even if a test sample is held vertically over an open flame. With this feature the bushing with its SIR insulator will not cause fire, not even maintain or develop a fire. Porcelain will of course not burn but it can explode or crack by extensive heating from fire sources and consequently increase the fire when the oil is let out from the bushing. Summary: The GSA bushings and the SIR are thoroughly tested according to relevant standards and the outdoor SIR insulators have proven their good performance during long time testing at test stations in severe environmental conditions.
Read morehttp://www.lanews.org/silicone-adhesives-and-sealants-market-challenges-and-opportunities-report-2016-2026/ Adhesivesand sealants have beenknown since centuries. They are primarily used for bonding of two differentsubstrates. Development in chemicals and polymers technology have broughtadhesives and sealants to the next level of industrial solutions. The uniquechemicals structure of silicone offers outstanding adhesion properties overother materials. Silicone bonds can resist great stress, pressure and can bestable over extreme temperature conditions. Due to its versatility, siliconeadhesives and sealants deliver reliable and long lasting adhesion to differentsubstrates ranging from glass, metals and plastics. Silicone adhesives andsealants offer unparalleled flexibility, resistance to extreme temperatures,durability, outstanding performance and making it suitable for variousapplications in electronics, aerospace, construction, automotive and healthcareindustry. Various types of silicone adhesives and sealants areavailable in the market such as one component, two component and UV curedadhesives, which differs on the basis of their functioning and benefits. Onecomponent adhesives are more convenient as no mixing is required and it has theability to cure at normal temperature. While the two component adhesivesrequire mixing and it can cure in thicker parts as compared to one componentadhesives. UV cured adhesives use electronic beam for curing without anyexcessive heat generation. Silicones have unique properties over otheradhesives such as temperature stability at high temperature and offerselasticity at low temperature. In addition, silicone has moisture resistanceand it is chemically inert which makes silicone adhesives and sealants suitablefor many industrial applications. Silicone material retains its properties over longperiod and gives excellent performance as compare to other materials due tostrength and flexibility. The unique properties of silicone adhesives andsealants make it suitable for various applications such as sealing wires inelectronics, structural glazing of façade in construction and medical tapes inhealthcare industry. The ability to resist chemicals and water, they have beenused for sealing engines and gaskets in the automotive industry. Silicone Adhesives and Sealants MarketSegmentation Based on the type: One Component, Two Component, UVCured; Based on the composition: Alkoxy Silicones, Acetic Silicones,Oximinics Silicones, Amino Silicones; Based on the end-use: Construction,Automotive, Marine & Aerospace, Electrical & Electronics, Healthcare,Packaging, Other End Use Industries. Rising use of UV curing technology and thermosets inthe manufacturing of product is expected to enhance production speed, improvescratch resistance and provides superior bonding, which in turn is expected toemerge as the most significant growth driver for global silicone adhesives andsealants market over the forecast period. Further, growing demand of adhesivesin the construction industry owing to their various physical and chemicalproperties as compared to other sealants including polysulfide, acrylic andpolyurethane is expected to fuel the demand of silicone adhesives and sealantsand thus driving the global silicone adhesives & sealants market. Silicone adhesives and sealants market is growing withfaster pace and trend is likely to continue for the next decade. Asia-Pacific,the largest market for silicone adhesives and sealants is the main contributorfor the growth of this market. However, volatile organic compound in siliconeadhesives and sealants and rising consumer awareness for environmental safetyis expected to restrain the growth of silicone adhesives and sealants. Thislimits the growth of global silicone adhesives and sealants market. Examples of some of the key players identified in theglobal silicone adhesives and sealants market include 3M, Henkel Corporation,ALSTONE, Mc Coy Soudal, Dow Corning Corporation, Momentive, Aerol FormulationsPrivate Limited, Wacker Chemie AG, MASTERBOND, AVERY DENNISON, Sika AG, ACCSilicones Ltd., American Sealants, Inc., Novagard Solutions, NITTO DENKOCORPORATION. Companies are largely focusing on product innovation for providingexceptional performance of the silicone adhesives and sealants.
Read morehttp://edition.cnn.com/2017/08/31/africa/kenya-plastic-ban/index.html By Osman Mohamed Osman, CNN Holding a pack ofplastic bags, Jonathan Mwagangi maneuvers through a crowd of shoppers inEastleigh, Nairobi's busy shopping market, looking for his next customer. For 15 years, the56-year-old has been selling plastic bags here, but his business will come toan abrupt end thanks to a new law from the Kenyan government. Starting on August 28it will become illegal to use, manufacture and import plastic bags forcommercial and household packaging. "The purpose ofthe government ban (on) the use of plastic bags is to avoid health andenvironmental effects resulting from the use of plastic bags," the National Environment Management Authority (NEMA), a stateagency that enforces environmental policies and laws, said in a statement. If found selling aplastic bag, suppliers like Mwagangi risk a jail term of up to fouryears or a fine of $38,000 or both. Dealers were given six months to cleartheir existing stock; that period is now over, and so is Mwagangi's business. "I sell plasticbags because it's my only source of income," Mwagangi tells CNN. "Iwill not have anything to sell unless manufacturers give alternative bags forpeople like me to continue working." Third time lucky? This isn't the first time the country hastried to tackle the issue of plastic bags. In 2007, Kenya tried to discourage theiruse by limiting the thickness of plastic bags, ordering manufacturers andimporters to only sell bags with more than 30 microns. Four years later, theytried again by banning plastic bags less than 60 microns, which were consideredmore recycle- friendly. Both plans failed. "This fell into technical hitches asit was hard for common citizens to differentiate the papers in terms of micronscontained in a given plastic paper bags. As a result, the enforcement was hardto sustain," says Evans Nyabuto, a NEMA spokesman. Nyabuto says it will be effective this timebecause plastic bags have been banned completely. He says the government hassufficiently educated the public about it, and support from major supermarketslike Nakumatt willprovide a boost. 'Kenya should be commended' The ban has been praised by The UnitedNations Environment Programme (UNEP), which estimates that Kenya uses about 24 million bagsevery month. Most of them find their way into the Indian Ocean, contributing tothe eight million tonnes of plastic dumped in the sea every year. "Kenya should be commended for itsenvironmental leadership," says Erik Solheim, the head of UN Environment."It's a great example that I hope will inspire others, and help drivefurther commitments to the Clean Seas campaign." Earlier this year, UNEP launched the "CleanSeas Initiative" in a bidto urge governments around the world to get rid of plastics entirely.UNEP predicts thatby 2050, the fish in the oceans will be outnumbered by pieces of plastic, threateningmarine ecosystems, wildlife and tourism. '1.2 million jobs at stake' But the ban has been met with someopposition. According to the KenyanAssociation of Manufacturers, there are 176 plastic bagmanufacturers in thecountry. "The direct employment created by the plastic sector is over2.89% Kenyan employees," says Phyllis Wakiaga, KAM CEO. "Indirectemployment and dependents through retailers, wholesalers, recyclers, packersand outlets is over 1.2 million personnel nationwide." Nyabuto counters thisargument by saying that the government has tried to engage with manufacturerson how to resolve "the menace of plastic bags in the environment," tono avail. "On a positivenote, the ban will create more employment" he says. "Industriesmanufacturing plastic bags will switch to manufacturing of the requiredbags." Dr. Leah Oyake-Ombise, an environmentspecialist in Nairobi, thinks that the government should invest in technologiesthat would help put a plastic waste management system in place. "We have failed to address (the) solidwaste management system. Nobody is talking about it. That's where we need toinvest," she said, adding that the government should look for"resources required and source for them to manage this sector." A change across the continent? Kenya joins more than a dozen Africancountries that have either banned or proposed the prohibition of plastic bags.They include Rwanda, Mauritania, Eritrea, Cameroon, Guinea-Bissau, Mali,Tanzania, Uganda, Ethiopia, and Malawi. So far, Rwanda's effort to do away withnon-biodegradable plastic is seen as the most successful among the Africancountries, and the country has maintained its stand. In 2008, Kigali was awarded the scroll of honor,a recognition by UN Habitat for "its slumclearance and upgrading of urban amenities, particularly refuse collection andthe provision of housing, water and sanitation." Rwanda, through itsrepresentative to East AfricanLegislative Assembly, fronted a bill that seeks to ban the use ofplastic bags in all East Africa Community member states. But the bill isstill being debated. The latest move byKenya will be seen as a boost for other countries to join hands and totally banthe use of these bags. Back in Eastleigh,Mwagangi is hoping that manufacturers will provide alternative bags for him tocontinue with his business. "The ban willmake people like me idle," he says.
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