PVC is a chlorinated hydrocarbon polymer and its basic building blocks are chlorine, carbon and hydrogen. These elements are obtained from two hydrocarbons, sea salt or sodium chloride (NaCl) and crude oil or natural gas.
Most of us use PVC every day. Around our homes, it is used in a wide range of products such as pipes for our fresh water, drainage pipes, floor coverings, window frames, cabling, toys, pool membranes, kitchen cabinetry, wall cladding, medical drainage tubingand food packaging.
PVC is equally useful at work where you will find PVC in furniture, stationery and in the equipment we use. Not surprisingly, PVC is the one of the most common plastics in the world. Not only can PVC be made into rigid or flexible products it can be made as either a coloured or transparent material.
PVC is typically the material of choice in the building and construction sector because of its high performance, affordability and environmental properties.
Light in weight - PVC performs well in lightweight construction systems where durability and strength is needed such as large area roofing membranes. Its lightweight also facilitates transportation, handling on-site and safe construction.
Rigid PVC is inherently difficult to ignite because of the chlorine from which the polymer is made. It stops burning once the source of heat is removed. Compared to other common plastic, PVC performs well in terms of lower combustibility, lower flammability, less flame propagation and less heat release.
Low cost is an important consideration with this high performance material. Ease of installation compared to alternatives, greater durability and lower maintenance requirements also make PVC competitive on a life cycle cost basis.
PVC has been in wide scale use for more than 50 years. It is one of the most researched and thoroughly tested building materials in the world. It meets international standards for safety and health for the applications for which it is used.
PVC is a very good electrical insulator and, therefore, an excellent material to use for applications such as insulation sheathing for electric cables. With low conductivity, it is an effective heat insulator, providing thermal efficiency in applications such as window and door profiles.
PVC is versatile. The physical properties of PVC allow designers a high degree of freedom as they design new products and develop solutions using PVC. PVC can be cut, shaped, welded, coloured and joined easily in a variety of styles.
Many PVC products are designed to last for decades.
Many PVC products find use in applications requiring durability, such as windows profiles, pipes & fittings, flooring, decking, power and telecommunication cables, electrical conduit, cladding, trunking, etc. Its superior toughness, fire resistance, chemical and corrosion resistance, long life-span and superior cost-performance ratio make PVC the ideal material for industrial applications.
The ability of PVC medical devices to withstand various sterilization methods makes it the product of choice for blood bags, intravenous tubing, masks, surgical gloves, and many other similar applications. The hygiene requirements for flooring and wall coverings at medical facilities place enormous demands on materials used. PVC has proven to be ideal for these applications, allowing for ease of disinfection which enables these facilities to offer life-saving services in hygienic conditions.
PVC continues to be widely used in cling film, shrink wrap, bottles and blister packaging, among others, based on its packaging properties. It exhibits excellent barrier properties which are vital for preservation of foodstuff, while its superior chemical resistance enables use in various pharmaceutical and other industrial packaging applications.
From high temperature wire harnesses to door panels, dashboards and upholstery, PVC has maintained presence in various automotive components despite the onslaught by other competitive materials. The introduction of heavy metal free stabilizer systems has placed PVC in a favourable position to meet stringent environmental and safety standards of the automotive industry.
PVC’s versatility enables use in many consumer products, including umbrellas, toys, shower curtains, footwear, gloves, banners and coated fabric. This versatility affords designers limitless opportunities to create fashion and artistic items of convenience to today’s modern society. Few other materials can lay claim to such variety of consumer applications as PVC.
PVC is one of the most researched polymer materials today, partly due to the pursuit of improved safety, health and environmental attributes of this material, but also due to misconceptions which have been shown to be either outdated or purely misleading. PVC products are today safely used to achieve various environmental and sustainability objectives predominantly as a result of the global PVC industry’s voluntary initiatives and partnerships with stakeholders. These initiatives have resulted in PVC being recognized for its sustainability credentials and subsequent reversal of previously adopted de-selection policies.
With the benefits of PVC products widely recognized and accepted, it remains important for the PVC industry to address perceptions which continue to persist in some quarters regarding this material.
A. Residual vinyl chloride monomer may be found in PVC as trace amounts which are regarded as safe for use in PVC packaging applications. PVC packaging products for food and medical applications must, similar to any other packaging material, meet strict regulations governing safety and health. In terms of international regulations, residual vinyl chloride monomer in all PVC packaging for food contact and medical applications must meet specification of maximum 1g VCM per ton of PVC. Most PVC manufacturers have adopted this specification to enable converters to comply with relevant food contact and medical legislation. Thus PVC products continue to be safely specified or used in the manufacture of blood bags, intravenous tubing, cling film, etc.
A: Not all PVC products contain lead, and where lead is used, it is normally locked within the polymer matrix following processing. For example, PVC pipes have for years been used to safely convey potable water while complying with strict health stipulations prohibiting toxic hazards, microbial growth and unpleasant tastes or odours. PVC packaging products have historically been free of lead and other heavy metal stabilizer systems.
A. SAVA’s Product Stewardship Programme (PSP) demonstrates support for responsible and sustainable use of additives used in the manufacture of PVC products. SAVA has recognized the importance of environmental sustainability and embraces the use of heavy metal free additives, compliance with food contact and other application-related regulations, while closely monitoring global trends affecting the vinyl value-chain. In line with these trends, lead free policies have already been adopted largely within the pipe and cable markets, with similar initiatives in progress in other sectors. These are done on voluntary basis without the need for regulation.
A: The sources of dioxins are not confined to PVC only. Dioxins form when various materials burn, such as wood, paper, cigarette smoke, and many other waste products. Studies have shown that no detectable amounts of dioxins could be found in PVC resin using available analytical techniques. Thus removing PVC from waste streams will therefore not necessarily result in any significant reduction of dioxin formation in the environment.
A. Manufacturing processes, whether PVC or many other industrial products, lead to some form of emissions. However, responsible PVC manufacturers comply with strict emissions standards and have demonstrable targets to continuously reduce such emissions. Incineration is used to capture and destroy most of the emissions, thereby further reducing potential environmental risks.
A. PVC has one of the best fire resistance properties of thermoplastic materials. Rigid PVC products are difficult to ignite and combustion will not be sustained without an external source of flame. Flexible PVC products used in buildings such as power cables are formulated with flame retardants and have to meet stringent fire specifications. Hydrogen chloride gas can easily be detected at very low concentrations due to its pungent smell, and is considered an irritant in building fires. However, carbon monoxide, which is odourless and is released by all organic materials when burning, is recognized as one of the main causes of deaths in fires, alongside heat.
A. Most PVC products are used in medium and long term applications that require durability and are known to last for many decades. This not only reduces PVC waste generation but also results in reduced maintenance costs for these applications. Many PVC products can be recycled a number of times for re-use while retaining performance properties. As an example, evidence exists that shows that PVC pipes retain mechanical properties for decades after installation and may therefore be safely re-worked to produce new pipe or other products. The challenge for all materials is the implementation of effective collection schemes and sorting of waste at community level. Recycling of post-consumer PVC scrap is one of the key focus areas of SAVA.
A.PVC products will continue to offer the best cost/performance ratio in the applications where they are used. With technologies such as biaxially oriented PVC (oPVC) pipes finding wide acceptance across the specifier community, the future does indeed look bright. The recent decision by the Green Building Council of Australia to recognize “best practice” PVC is indicative of how the global PVC industry has taken the challenge of sustainability to heart. The Southern African PVC industry is very much part of these trends!
This compilation is based on research of various publications and information available in the public domain. Examples of sources of information are listed below.
Information sources for further reading: