Specialty Polymers
R. W. DYSON There will be few readers of this book who are not aware of the contribution that polymers make to modern life. They are to be seen around the home, at work, in transport and in leisure pursuits. They take many forms which include plastic moul
- PDF / 293,735 Bytes
- 2 Pages / 431 x 649 pts Page_size
- 34 Downloads / 202 Views
There will be few readers of this book who are not aware of the contribution that polymers make to modern life. They are to be seen around the home, at work, in transport and in leisure pursuits. They take many forms which include plastic mouldings and extrusions, plastic film and sheet, plastic laminates (fibreglass and formica) rubber gloves, hoses, tyres and sealing rings, fibres for textiles and carpets and so on, cellular products for cushioning and thermal insulation, adhesives and coating materials such as paints and varnishes. The majority of these polymers are synthetic and are derived from oil products. The most important of these in terms of tonnage used are polymers based upon styrene, vinyl chloride, ethylene, propylene and butadiene among plastics and rubber materials, and nylons, polyethyleneterephthalate and polyacrylonitrile among fibres. The total amount of these polymers used each year runs into millions of tonnes. These polymers are sometimes known as commodity polymers because they are used for everyday artefacts. They are available in many grades and formats to meet a variety of applications and processing techniques. The properties can be adjusted by using additives such as heat and light stabilizers, plasticizers, and reinforcing materials. Often, grades are specially designed and formulated to meet particular requirements and, in a sense, these might be regarded as specialities. Much has been written about these materials elsewhere and they are not the concern of this book. Instead, this book is concerned with a wide range of polymers which have been designed and created to meet special needs which often involve properties not usually associated with polymers. There has been a growing awareness over the last 20 years or so that there are many advantages to using polymers in applications which previously would not have been considered suitable or feasible. A great deal of research and development has gone into creating polymers to meet the demands of these specialized applications. Much of modern technology would hardly be possible without their use. The electronics industry, for example, could not have developed as it has without the use of polymeric materials which have been created to meet the most exacting requirements. Compared with the commodity polymers, the tonnage production of these polymers is small, being measured in tonnes each year. They are usually costly, partly because the quantities required are small and partly because the processes for making R. W. Dyson (ed.), Specialty Polymers © Blackie & Son Ltd 1987
2
SPECIALTY POLYMERS
them are themselves expensive. Nevertheless, all of the polymers discussed offer a unique combination of properties for a particular application and it is this which marks them as specialty polymers. The inclusion of polyurethanes might seem a little strange but they are specialty polymers in a different sense. They are unique in the enormous diversity of product types that can be obtained. Subtle changes in properties within types can readily be
Data Loading...
