This project is written to give a practical knowledge of the assessment of finishing using PVC in modern Building. This research is more of reportorial and description any descriptive analysis of finding. It is in four chapters.
Chapter one consist of introduction of the study and History, also the literature review was discussed in the second chapter, chapter three highlight research methodology and details of instrument used for the study. Chapter four deals with the Conclusion; finding and overall summary and recommendation arising from the study.
Polyvinyl chloride (PVC) is prepared from the organic compound vinyl chloride (CH29CHCl). PVC is the most widely used of the amorphous plastics. PVC is lightweight, durable, and waterproof. Chlorine atoms bonded to the carbon backbone of its molecules give PVC its hard and flame-resistant properties.
In its rigid form, PVC is weather-resistant and is extruded into pipe, house siding, and gutters. Rigid PVC is also blow molded into clear bottles and is used to form other consumer products, including compact discs and computer casings.
PVC can be softened with certain chemicals. This softened form of PVC is used to make shrink-wrap, food packaging, rainwear, shoe soles, shampoo containers, floor tile, gloves, upholstery, and other products. Most softened PVC plastic products are manufactured by extrusion, injection molding, or casting.
PVC is capable of playing an important role in sustainabledevelopment. One prerequisite is that political decisions are made based on proven criteria. Considerable improvements in raw material and energy efficiency have been established in the current ecological profiles on manufacturing PVC.The low life-cycle costs of many PVC products allow for the financing of important ecological and social improvements. Progress in recycling and disposal has greatly resolved the problem of waste. Many formerly, fiercely-debated topics concerning risk (substitution of problematic additives) could be defused. This has lead to a scientific and political re-evaluation of PVC.
Environmental, economic, and social policy is oriented towardsthe guiding principle of sustainable, future-oriented development. Cost-effective products such as those made of PVC are economically, ecologically, and socially “competitive”.
PVC offers many positive prerequisites for sustainable development for our industrial society through:
- low-energy expenditure in manufacturing and processing
- the use of the practically unlimited resource of salt
- the combined production of chlorine and sodium hydroxide
- low emissions and waste during manufacturing and processing
- mechanical and feedstock recycling
- good price-performance ratio of products along with environmental costs
- immense ecological/social optimization potential based onoutstanding economical advantages.
PVC is a modern, high-performance material which will be urgentlyneeded in the future as well. The low share of crude oil saves limited resources and increases the economic efficiency of this material. Longevity and resistance to environmental factors make PVC the material of choice for economic planning and sustainable construction.
1.1.1 Manufacturing and Raw Materials
The European PVC industry has consistently improved its manufacturing processes in recentyears. This is especially true for formulas. Thus, there have been considerable changes in the use of stabilizers and plasticizers.
Synthesis of Crude Oil and Rock SaltCrude oil/natural gas and rock salt are the starting productsfor PVC manufacturing. Ethylene is the result of crude oil inthe intermediate stage of naphtha through thermal “cracking”.Chlorine, on the other hand, is produced from rock salt throughchloralkali electrolysis. For this purpose the modern, energysavingmembrane process is commonly used today. Sodiumhydroxide and hydrogen are thereby produced as importantby-products. In turn, they are the raw materials for many othersyntheses. Vinyl chloride (VC) is produced from ethylene andchlorine at a ratio of 43% to 57%. VC is the monomeric buildingblock of PVC. The transformation of VC to PVC takes placethrough various technological processes.
PVC products are derived from a white, odorless powder which is mixed with additives for the further processing of semi-finished and finished products. Such admixtures are not only found in practically all plastics, but also in materials such as glass, steel, concrete, etc. Basically, the following additives are use:
- stabilizers and co-stabilizers
- polymer agents to improve tenacity, heat-and-form stability, and processing performance
Additives facilitate processing and simultaneously determinethe properties of end products. The choice of additives depends on processing procedures and demands on the finished products. Depending on the choice of additives, PVC as a rawmaterial is developed into sturdy, thick-walled pipes for drinking water or extremely thin, flexible film for packaging fresh meat. Additives thereby provide a wide range of product properties.
The use of stabilizers guarantees sufficient heat stability for PVC during processing and protects the end product from change due to heat, UV-light, or oxygen. Especially inorganic and organic salts of the metals calcium, zinc, barium, lead and tin are added to PVC products. These salts are firmly anchored in the polymer matrix. They are not released during the use of these products. The use of stabilizers has undergone a significant change in recent years. One reason for this was that the
European industry discontinued the sale and use of cadmium stabilizers in all EU member states. In addition, the European Stabilizer Producers Association (ESPA) and the European Plastics Converters Association (EUPC) agreed to the voluntary commitment “Vinyl 2010” in October 2001 to replace lead stabilizers. Several intermediate goals have therefore been established (basis: consumption in 2000):
- 15 % reduction in 2005
- 50 % reduction in 2010
- 100 % reduction in 2015.5
The goal for 2010 was surpassed in 2008. The reduction of leadstabilizers was already at ca. 76% in 2010. At the same time, the research and development of alternative stabilizer systems in
recent years has made enormous stride at great financial cost.In addition to systems based on calcium/zinc, whose market share in Western Europe increased from 5% in 1994 to over 50% today, tin also plays an important role. Moreover, new developments utilize metal-free organic stabilizing systems.
The amount of thermal stabilizers used in mixtures has beenreduced in recent years through effective additives and more exact engineering processes. Recycled materials might contain cadmium and lead due to the recycling of older products. This is permitted by law in order to create incentives for the use of recycled materials.6 Directive 494/2011 by the EU Commission from 20 May 2011 regulated the use of recycled materials containing cadmium.
Approximately 70% of PVC produced is used in Europe to manufacture rigid products such as window profiles and pipes, which are distinguished by their longevity and weather resistance.
The remaining 30% covers soft applications. Plasticizersprovide PVC with special properties of use similar to those of rubber. This naturally hard material becomes flexible and elastic through plasticizers. At the same time, it retains its shape.
Soft PVC can be applied to a wide range of products in various ways. Pastes made of a mixture of PVC and plasticizers expand the range of possibilities, e.g. by means of expressive vinyl wallpaper or easy-to-clean flooring. Soft PVC is distinguished by its outstanding properties of use which offer a versatile range of possibilities. Flexible products such as artificial leather, weather-resistant roofing membranes, or flame-retardant cables enhance our lives and make them safer and more comfortable. In medical care, soft PVC applications have stood the test of time for decades. Blood bags, tube systems, and wound dressings are essential components of patient care. PVC products are even recommended for allergy sufferers due to their compatibility.
The most frequently used plasticizers are esters from phthalicacid. In terms of application, a change has taken place on the European market in recent years in favour of high-molecular weight plasticizers. The largest share is made up of DINP and DIDP.8 These substances have extensively replaced low-molecularweight plasticizers on the market such as DEHP, DBP, and BBP
Processing And Products
PVC can be processed into various products in a number of ways. The range extends fromheat-insulating, energy-saving windows to sturdy pipes and easy-to-clean floor coverings. Approximately seventy percent of PVC materials are used in the building sector, many of which are long-life products.
Extruder or Injection Moulding
PVC is one of the few polymers which can be processed thermo plasticallyand by means of pastes.14 Thermoplastic processestake place primarily on extruders or so-called screwpresses. The final products are pipes, profiles, sheets, tubes,and cables.15 Film and floor coverings are created by meansof calendar (rolling mills). Fittings and casings are producedin the injection moulding process and hollow bodies by blowmoulding.
Emulsion and micro-suspension PVC is applied as a paste tovarious soft PVC products such as tarpaulins, flooring, coverings,and artificial leather. As an alternative, rotation mouldingis used to shape dolls and balls.
A Wide Range of Products
PVC can be used in numerous products due to its outstandingproperties and therefore is an integral part of our lives.
In Germany, approximately 70% of all PVC applications are intendedfor the construction sector. In particular, this includeswindow profiles, pipes, floor coverings, and roofing membranes.
PVC windows are weather resistant, durable, easy to clean, economical,and recyclable at the end of their life cycles. Sturdypipes made of rigid PVC transport valuable drinking water,drain roofs, and dispose of sewage water. They can be easily,safely, and economically installed by means of structural andcivil engineering. Building products made of PVC are distinguishedespecially by their longevity: this is a decisive criterionfor selecting the appropriate material.
In the packaging sector PVC is found in special applicationssuch as blister packs, adhesive tapes, hollow bodies, and cups. Cables and wires with an insulation or coating made of soft PVC play a decisive role in the smooth operations of our daily lives in terms of energy supply, control functions, and communications. Protective undercoating, interior panelling, and cable harnesses inside vehicles and under the bonnet play an important role in the automotive sector.
In addition, medical products such as blood bags or tubes, office articles, garden
equipment and furniture, and tarpaulins are indispensable.
These examples alone demonstrate the versatile possibilities
of applications for PVC.
Versatile Material Properties
PVC is an all-around talent: it is hard and durable or soft andflexible as need be. Simple changes in the formula allow for practically any desired material property. Therefore, PVC exists
crystal-clear or colluded, electrically well-insulating or antistatic.
This durable plastic is largely resistant to chemicals,weather and abrasion, and harmless to human health. Moreover, the chlorine content makes the material highly flame retardant. Further advantages of the material include efficient production and easy processing as well as the material-saving manufacturing of consumer goods.
1.1.3 Characteristics of PVC
PVC, PE, PP and PS are called general purpose plastics. The features of the plasticare determined by the chemical composition and type of molecular structure (molecular formation: crystalline /amorphous structure). PVC has a unique amorphous structure with polar chlorine atoms in the molecular structure. Having chlorine atoms and the amorphous molecular structure are inseparably related. Although plastics seem very similar in the daily use context, PVC has completely different features in terms of performance and functions as compared with olefin plastics which have only carbon and hydrogen atoms in their molecular structures.
(1) Chemical stability
Chemical stability is a common featureamong substances, containing halogens such as chlorine and fluorine. This applies toPVC resins also, which furthermore possess fire retarding properties, durability, and oil/chemical resistance.
Fire retarding properties: PVC has an inherently superior fireretarding property due to its chlorine atomcomponents, and do not require addition offire retardants to its products. For example,the ignition temperature of PVC is as highas 455
and is a material with less risk forfire incidents since it is not ignited easily(Fig.1-13).
Furthermore, the heat radiation inburning is considerably low with PVC, whencompared with those for PE and PP, and ishard to spread fire to nearby materials evenwhile burning (Fig.1-14). Therefore, PVCis the most suitable plastic to be used inproducts requiring fire retarding propertiessuch as housing materials.
Under normal conditions of use, the factormost strongly influencing the durability ofa material is resistance to oxidation withinthe air. PVC, having the molecular structurewhere chlorine atom is bound to every othercarbon chains, is very resistant to oxidativereactions, and maintains its performance almost semi-permanently. In contrast, other general purpose plastics with structures made up only of carbon and hydrogen are susceptible to deterioration by oxidation in extended use conditions.
According to measurements on underground PVC pipes by the Japan PVC Pipe & Fittings Association, a pipe used underground for 35 years showed no deterioration, and its strength remained the same as with new pipes (Fig.1-15).
(2) Mechanical stability
PVC is a chemically stable material, which shows little change in the molecular structure, and also exhibits little change in the mechanical strength.
However, high-polymer material is a viscoelastic bodyand deformed by continuous application of exteriorforce, even if the applied force is well below its yield point. This is called creep deformation. Although
PVC is a viscoelastic body, its creep deformation isvery little compared with other plastics due to little molecular motion at ordinary temperature, in contrast to PE and PP, which have greater molecular motion in their amorphous sections. Through a joint research with the Kyoto Institute of Technology, it was found out that the service lives of rigid PVC pipes were over 50 years. Specifically, internal pressure creep tests revealed that rigid PVC pipes retain about three times the designed circumferential stress even after 50
(3) Process ability and moldability
The process ability of a thermoplastic materialdepends largely on its melt viscosity. PVC is not meant for injection molding of large sized products, since its melt viscosity is comparatively high. On the other hand, the viscoelastic behavior of molten PVC is less dependent on temperature and is stable. Therefore PVC is suitable for complex shaped extrusion profiling (e.g., housing materials), as well as calendaring of wide films and sheets (e.g., agricultural films and PVC leather). The exterior surfaces of molded
PVC products are excellent, and displays superiorembossing performance – enabling a wide variety of surface treatments with textures ranging from enamel gloss to the completely DE lustered suede. Since PVC is an amorphous plastic with no phase transition, molded PVC products have high dimensional accuracy.
PVC also exhibits excellent secondary process ability in bending fabrication, welding, high-frequency bonding, and vacuum forming, as well as on-site workability. Paste resin processing such as slush molding, screen printing and coating is a convenient processing technique that is feasible only with PVC. These processing methods are used in flooring, wall covering, automobile sealants and undercoating.
(4) Others (versatility in designing through compounding)
PVC has polar groups (chlorine), and is amorphous,therefore mixes well with various other substances. The required physical properties of end products (e.g., flexibility, elasticity, impact resistance, anti-fouling, anti-bacteria, anti-mist, fire retarding) can be freely designed through formulation with plasticizers and various additives, modifiers, and coloring agents. PVC is the only general purpose plastic that allows free, wide and seamless adjustment of the required physical properties of products such as flexibility, elasticity, and impact resistance, by adding plasticizers, additives, and modifiers.
Since the physical properties ofend products are adjustable through compounding, it requires only a few types of resin to cover all the applications of high-polymer materials (fiber, rigid and flexible plastic, rubber, paint, and adhesive). This controllability is also extremely beneficial recycling wise.
The polar groups in PVC contribute to ease in coloring, printing and adhesion, therefore PVC products do not require pretreatment, which enables a wide variety of designs. PVC is used in various scenes taking full advantage of its superior printability, adhesion properties andWeatherability. Patterns such as wood grain, marble, and metallic tones are possible. Familiar examples include wall coverings and floorings, housing materials, furniture, home electric appliances, or signboards and ads on airplanes, bullet trains, buses and trams.
(1) Production safety
VCM, which is the intermediate raw material forPVC, has a boiling point of – 13.9and a flash point of – 78. Caution is required upon handling since it is a dangerous substance in gaseous form. The PVC industry in Japan handles VCM with utmost care at PVC manufacturing facilities and has safe working environments. No hazard has ever been brought to local communities. Neither has there been any deathincidence or sufferers due to improper manufacturing process control throughout the years.
(2) Safety upon use
PVC is a chemically and mechanically stable materialwith excellent fire retarding properties, and is a safe plastic under normal conditions of use. Fig.1-19 is an excerpt of the Material Safety Data Sheet (MSDS)prepared by PVC manufacturers. The MSDS shows data for the safe use of PVC.
(3) Evaluation of carcinogenicity
In 1974, cancer incidents were reported amongworkers who had been employed by the PVC industry in the U.S., and VCM were reported to be responsible.
As a result of an epidemiological survey, a very raretype of cancer (angiosarcoma) was identified in workers who had been exposed to high concentrations of VCM for an extended period of time.
Following this report, improvements of workenvironments were accelerated through closed system EDC/VCM manufacturing processes and automated cleaning of PVC polymerization reactors, in the U.S. and across of the world.
In Japan, a new guideline was introduced in 1975where the geometrical average was to be within 2ppm in the general work environments and within 5ppm inside the polymerization reactor. Subsequently, better process control technologies were introduced such as enhanced polymerization rates and recovery of unreacted VCM from the reactor. The PVC industry also worked on the reduction plan for hazardous air pollutants in cooperation with administrations There were once cancer incidents among workers who cleaned polymerization reactors for extended
(4) Residual monomers in PVC
Trace amounts of unreacted VCM are found in PVC,but their concentrations are not a problem upon processing and use of PVC products. Food packaging and medical appliances require stringent safetymeasures; therefore the following specifications have been established.
1.2 History of Plastic
For more than 50 years, PVC has been very successful throughout the world. Today, this
versatile material is one of the most important plastic materials recognized internationally and proven on the market.
PVC has distinguished itself especially with its wide range of applications. PVC products are often cost-effective in terms of purchasing and maintenance. At the same time, they contribute more and more to sustainable development throughout their entire life cycle: this occurs by means of state-of-the-art manufacturing and production methods, the responsible use of energy and resources, cost-effective manufacturing and processing, as well as numerous recovery possibilities. This progress has led to a continuous increase in the demand for this plastic material. Moreover, through cost-effective PVC products, society saves money which can be spent on sound ecological and social investments.