An Intoduction to Vinyl (Poly Vinyl Chloride)
History
The world's most versatile plastic had a rather humble beginning: A rubber scientist during the early 1920s stumbled onto a new material with fantastic properties during his search for a synthetic adhesive. Waldo Semon was intrigued with his finding, and experimented by making golf balls and shoe heels out of the versatile material called polyvinyl chloride, or PVC.
Soon after his discovery, PVC-based products such as insulated wire, raincoats and shower curtains hit the market. As more uses for vinyl were discovered, industry developed more ways to produce and process the new plastic.
The 1930’s
Plants manufacturing PVC began to spring up during the '30s to meet demand for the versatile material. Just a decade after its conception, PVC - commonly known as vinyl - was sought for a variety of industrial applications including gaskets and tubing.
The 1940’s
Joining industries across the nation during the '40s, PVC manufacturers turned their attention to assisting the war effort. Vinyl-coated wire was widely used aboard U.S. military ships, replacing wire insulated with rubber. Vinyl manufacturers were working in high gear as World War II wound down, and they quickly found new markets for the durable plastic. Following the war, news of vinyl's versatility and flame-resistant properties spread, leading to dozens of commercial uses.
The 1950’s and 1960’s
Five companies were making PVC at the century's midpoint, and innovative uses for vinyl continued to be found during the '50s and '60s. A vinyl-based latex was used on boots, fabric coatings and inflatable structures, and methods for enhancing vinyl's durability were refined, opening the door to applications in the building trades.
The 1970’s
Vinyl products quickly became a staple of the construction industry; the plastic's resistance to corrosion, light and chemicals made it ideal for building applications. PVC piping was soon transporting water to thousands of homes and industries, aided by improvements in the material's resistance to extreme temperatures. Twenty companies were producing vinyl by 1980.
Today
Today, vinyl is the second largest-selling plastic in the world, and the industry employs more than 100,000 people in the United States alone. Vinyl's low cost, versatility and performance make it the material of choice for dozens of industries such as health care, communications, aerospace, automotive, retailing, textiles and construction. Rigid as pipe or pliable as plastic wrap, vinyl is a leading material of the 21st century.
What is Vinyl?
Vinyl (polyvinyl chloride or PVC), is the world's most versatile plastic, used to make everything from food wrap to auto body parts. Vinyl is composed of two simple building blocks: chlorine, based on common salt, and ethylene, from crude oil.
The resulting compound, ethylene dichloride, is converted at very high temperatures to vinyl chloride monomer (VCM) gas. Through the chemical reaction known as polymerisation, VCM becomes a chemically stable powder, polyvinyl chloride resin.
Interesting Vinyl Statistics
· Vinyl is the second largest-selling plastic and the most versatile one.
· The vinyl resin industry has more than $4 billion in sales and employs more than 100,000 people.
· Vinyl is used in hundreds of consumer, industrial products.
· More than 14 billion pounds of vinyl are produced annually in North America.
Recycling
Even after a useful lifespan of decades, vinyl products can be recycled into new applications lasting decades more.
Manufacturing Scrap
A significant amount of vinyl scrap (coming from polymer manufacturers and plastic processors) is collected and recycled. Overall, more than 99 percent of all manufactured vinyl compound ends up in a finished product, due to widespread post-industrial recycling.
Post-Consumer Recycling
Post-consumer vinyl recycling continues to grow as an increasing number of recycling programs are equipped to handle vinyl bottles. The Vinyl Institute has supported the development of technology to automatically separate one plastic from another (a key to making plastics recycling successful). Several vinyl recycling systems have been developed around the nation by innovative companies with the encouragement of the Vinyl Institute. Researchers have found that vinyl can easily be separated from other plastics automatically because technology can spot its unique chlorine chemical composition.
Recycling Statistics
According to a 1999 study by Principia Partners, more than one billion pounds of vinyl were recovered and recycled into useful products in North America in 1997. About 18 million pounds of that was post-consumer vinyl diverted from landfills and recycled into second-generation products.
The Vinyl Institute is working to increase the number of communities recycling vinyl since studies show that the estimated demand for recycled vinyl is about twice the potential supply.
· PVC can be, and is being recycled.
· Automatic sorting of vinyl is now possible.
· Demand for recycled vinyl far exceeds the supply.
Vinyl Lifecycle
Vinyl has become one of the most widely used materials in part because of its cost efficiencies. These efficiencies begin when vinyl is produced and continue throughout its lifecycle, encompassing such elements as raw material usage, energy used in processing, energy used in distribution and transportation, durability, maintenance requirements and disposal costs. Vinyl consistently scores better than other materials in many economic and environmental performance categories.
Vinyl's beneficial qualities affect every aspect of our lives. Because it will not rust or corrode, vinyl is widely used in water pipe to deliver clean water and in sewer pipe to ensure the integrity of wastewater handling systems. PVC pipe installations last up to 50 years, reducing raw material consumption. Vinyl is also the material of choice for blood bags and tubing, helping maintain the world's blood supply and supporting critical healthcare procedures such as dialysis.
In packaging, vinyl helps to keep food safe and fresh during transportation and on store shelves, and provides tamper-resistant packaging for food, pharmaceuticals and other products. Vinyl's resistance to high electrical voltage and its ability to bend without cracking make it the leading material for wire and cable insulation. It helps add years to the life of motor vehicles as an under body coating. Vinyl's toughness and durability make it the most widely used plastic for building and construction applications such as siding, windows, single-ply roofing membranes, fencing, decking, wall coverings and flooring.
· Over 50 percent of the vinyl polymer comes from an inexpensive, renewable resource.
· Selected vinyl products are shown to have a distinct lifecycle advantage over competitive materials.
· Vinyl has demonstrated its utility and value worldwide.
Vinyl and the Environment
Conservation of natural resources
Only 43 percent of vinyl comes from nonrenewable petroleum feedstocks. The balance (57 percent) comes from salt.
According to an independent study, vinyl uses less energy to make, generates fewer emissions and requires fewer natural resources than some of the other leading packaging materials.
In transportation and construction applications, vinyl is one of three plastic materials with the lowest energy requirements of the 12 major plastics used. It saves more than 34 million BTUs per 1,000 pounds manufactured compared to the highest energy-consuming plastic.
Incineration
Vinyl can be safely incinerated in state-of-the-art facilities and its energy recaptured and reused.
A number of studies, including one by the New York State Energy Research and Development Authority (NYSERDA), have found that the presence or absence of vinyl has no effect on the amount of dioxin produced during the incineration process. Rather, incinerator operating conditions (primarily temperature) are the key to controlling dioxin formation.
A 1995 study sponsored by the American Society of Mechanical Engineers (ASME), involving the analysis of more than 1,900 test results from 169 large-scale commercial incinerator facilities throughout the world, found no relationship between the chlorine content of waste like vinyl and dioxin emissions from combustion processes under real-life conditions. Instead, the study stated, the scientific literature is clear that the operating conditions of combustors are the critical factor in dioxin generation. Additionally, the Swedish Environmental Protection Agency declared in June 1996 that, "Reducing the quantity of PVC in waste does not reduce the quantity of dioxin in the waste gases."
Incinerator scrubbing systems can remove about 99 percent of the hydrogen chloride (HCl) generated by incinerating vinyl plastics and other chlorine-containing compounds and materials.
Also, a study by the Midwest Research Institute determined that wastes containing vinyl plastics are not a significant factor in cost-effectively operating either medical or municipal solid waste incinerators.
Landfilling
Vinyl products are extremely resistant to the corrosive conditions found in landfills and will not break down or degrade under them. In fact, vinyl is often used to make landfill liners because it is inert and stable.
Chlorine
Vinyl won't harm the atmosphere. Once chlorine is processed into vinyl, it is chemically locked into the product more tightly than it was in salt. When vinyl is recycled, landfilled, or disposed of in a modern incinerator, chlorine gas is not released into the atmosphere.
Environmental Summary
· Vinyl can be safely incinerated or landfilled.
· Operating conditions, not vinyl, affect dioxin creation in incinerators.
· Vinyl conserves natural resources and is good for the environment.
Vinyl and Health
Worker health hazards resulting from prolonged, high exposure to vinyl chloride monomer (VCM) came under scrutiny by the Occupational Safety and Health Administration (OSHA) and the EPA in the late 1970s. Through new manufacturing technology, industry was able to address those problems.
Vinyl production facilities are regulated by the Occupational Safety and Health Administration, and all emissions are regulated by the EPA and reported under state and federal law.
Health Risk Estimates
The EPA has estimated that the industry's VCM emissions have been reduced by more than 99 percent since the 1970s. Moreover, there is no confirmed case on record in which a member of the general population has been harmed by exposure to VCM. The actual risk among the five million individuals presumed to live within five miles of a VCM or vinyl production facility has been calculated to be less than 0.1 case of cancer in the next 70 years. This compares with the risk over a lifetime of smoking 1.4 cigarettes or drinking one-half litre of wine; travelling 10 miles by bicycle, 300 miles by car or 1,000 miles by jet; or having one chest X-ray. No other confirmed community health effects have been linked to the presence of vinyl or VCM production facilities.
In its recent review of the toxicological data on vinyl chloride, the EPA reduced its cancer unit risk estimate for vinyl chloride to 20 times lower than its previous estimate.
Dioxin Emissions
The vinyl industry's dioxin emissions are a very small part of overall emissions, constituting less than one-half of one percent of the total emissions to air, water and land as identified by the EPA. The vinyl industry emits about 12.6 grams of dioxin a year, compared to the EPA's recent estimate of nearly 3,000 grams a year from known sources. The EPA also stated that dioxin emissions in the United States decreased by about 80 percent between 1987 and 1995, primarily due to reductions in air emissions from municipal and medical waste incinerators. Notably, while the amount of dioxin in the environment has decreased sharply over the past 30 years, VCM production has more than tripled - which is the best evidence that the vinyl production chain is a minor contributor to dioxin levels in the environment.
· Close regulation makes vinyl production safe.
· Vinyl production poses no risk to community health.
· PVC production is a "classic case of waste minimization."
· Vinyl production is a minimal contributor of dioxin.
· Vinyl industry is working with the EPA to ensure safety.
Vinyl and Fire
Vinyl products are inherently flame-retardant due to their chlorine base, do not readily ignite and most will not continue to burn once a flame or heat source is removed.
Unlike metal tubing, vinyl conduit will not arc or short, thereby reducing the hazard of fires in electrical applications.
Combustion by-products
The products of vinyl combustion are no more hazardous than those produced by many other common materials, both natural and synthetic. When it burns, vinyl does release hydrogen chloride (HCl), but studies have shown that HCl does not incapacitate or become dangerous until it reaches concentrations much higher than those measured in real fires.
Systematic investigations of large-scale accidental fires in Germany, Sweden and Canada have indicated that dioxins will be produced in accidental fires whether vinyl is present or not, and that the quantities produced in such fires posed no threat to human health or to the environment. A recent analysis conducted by one of the industry's leading authorities on vinyl's fire performance found that fires involving the combustion of vinyl products most likely contribute less than half a gram per year to overall airborne dioxin emissions.
· Chlorine in vinyl helps stop it from burning.
· Tests show PVC not an unusual fire hazard.
· Its properties make vinyl an ideal material in electrical applications.
Additives
Many polymers, including vinyl, require additives during the manufacturing process. Individual additives include heat and light stabilizers, colorants, impact modifiers, processing aids and plasticizers.
Additives typically constitute a small part of the overall vinyl formulation and their use is closely regulated by a number of agencies including the U.S. Environmental Protection Agency (EPA), the Food & Drug Administration (FDA) and the National Sanitation Foundation (NSF). All additives used in food and drug applications must have specific regulatory clearance from the FDA.
Plasticizers
Plasticizers are used as softening agents and provide low temperature flexibility and weldability. Phthalate ester plasticizers have been safely used for more than 50 years and are some of the most studied compounds in the United States from a health and environmental viewpoint. These plasticizers are used in wire and cable products, medical devices, toys, flooring, shower curtains and synthetic leathers such as automotive upholstery, as well as in pharmaceuticals and personal care products such as cosmetics and lotions. Their versatility and excellent performance prolongs products' service life, gives them resistance, and helps reduce spoilage and waste.
Independent scientists, international government bodies and phthalate producers have conducted extensive studies on the safety, health and environmental effects of phthalates. There have been no confirmed reports of adverse health effects in children or adults from phthalate exposure. A blue-ribbon panel of leading physicians and scientists chaired by former U.S. Surgeon General Dr. C. Everett Koop concluded in 1999 that vinyl toys and medical devices made with phthalate plasticizers are not harmful to children or adults.
Stabilizers
The principal metals from which stabilizers are made include tin, barium, zinc, calcium and, decreasingly, lead and cadmium. Most stabilizers are used in rigid vinyl applications such as construction products thanks to their processability and durability. Lead-based stabilizers are used principally in vinyl wire and cable insulation.
Because the additives are firmly bound within a rigid vinyl matrix, there is no mechanism by which these additives can escape into the environment at levels that pose a health risk to humans. Lead and cadmium stabilizers are not used in food packaging or toys. In fact, strict regulations on the use of lead in toys exist both within the international toy industry and under U.S. federal law. Building wire, usually used inside walls and away from regular human contact, must meet strict insulation standards.
New studies affirm that disposal of metal-stabilized vinyl waste in landfills poses no appreciable risk to human health or the environment. In fact, vinyl sheet is used as landfill liner to help prevent leachate from contaminating groundwater, specifically because vinyl is so resistant to the aggressive conditions typically found there.
In short, the demonstrated performance and scientific facts about stabilizers confirm that they are the right choice for most rigid vinyl processing. Extensive testing and review have shown that there is no risk to processors, consumers or the environment when these stabilizers are used as intended.
· Vinyl plasticizers are well-researched; found to be safe.
· Heavy metal stabilizers are used selectively and do not represent a health or exposure risk.
· Additives do not hamper the recyclability of vinyl.
Key Properties
Because PVC resin can be combined with many additives and modifiers, vinyl can meet the requirements for products in many industries.
Vinyl is often chosen over other materials because of its low cost, versatility and performance properties.
Vinyl is strong, durable, abrasion and moisture resistant; withstands rust and corrosion; is electrically non-conductive and has excellent fire performance properties.
Colour Availability
Vinyl can be produced in almost any colour, with end products ranging from opaque to crystal-clear.
Versatility
Through a variety of extrusion, calendering and moulding processes, vinyl is used in products as rigid as pipe or as flexible as upholstery and food wrap.
Economics
Because it is less than half petroleum, vinyl is the most energy-efficient plastic. And because it has been used for more than a half century, it is one of the world's most analysed and tested materials.
· Vinyl comes from salt, an inexpensive, renewable resource.
· Vinyl products consume less energy, generate fewer emissions and save more energy than many competitive products.
· Most vinyl products are durable and long-lived.
Applications
· Vinyl's largest use is in construction.
· It is one of the most time-tested synthetic materials in use.
· Vinyl is critical to many quality-of-life products.
Building Products
Vinyl is especially widely-used in construction, in products like water pipe, house siding, window frames, gutters and downspouts, floor tile, electrical wire and cable insulation and wall coverings.
Packaging
Flexible vinyl film is a leading packaging material for wrapping meats and produce, and for tamper-proofing over-the-counter medications and food products. Rigid vinyl film is widely used in the blister and clamshell packaging that protects hardware items. Vinyl bottles store everything from peanut butter and cooking oil to shampoo, lighter fluid and motor oil.
Appliances
Vinyl is used in parts for appliances, computers and automobiles, in fibre optics and electronics, as well as in consumer and institutional goods like shower curtains, window blinds, garden hoses, footwear and credit cards.
Medical Applications
Vinyl's medical uses include blister packaging for pharmaceuticals, blood bags, heart catheters, tubing and surgical gloves.
Recycled Applications
Scrap vinyl is being recycled into a variety of new and useful products, including:
· Bottles
· blister packaging
· floor tiles and mats
· garden hoses
· fencing
· truck bed liners
· automotive applications
· pipe
· boots
· notebook covers
· traffic cones
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