What is Plastic?
The Plastic is an organic substance and it consists of natural or synthetic binders or resins with or without molding compounds. It is also used as an engineering material available in the market all over the world. To know the importance of plastics as an engineering material , it will be interesting to know about its properties.
Example of Plastics as a Construction Material
In Beijing , capital of china , Beijing national aquatic center (water cube) named structure was constructed for the purpose of swimming competitions in 2008 Olympics. The structure consists of steel frames which are covered by ETFE pillows (ethylene Tetra Fluoro Ethylene) which is a fluorine based plastic.
ETFE plastic have high corrosive resistance and as well as high strength against temperature. This is the largest ETFE structure in the world.
Properties of Plastics as a Construction Material
Each plastic material has its own peculiar properties to suit its particular uses. The success of plastic as an engineering material will depends up on the selection of variety of plastic. Following are the general properties of plastic.
Appearance of Plastics
In the market there are so many types of models of plastics are available such as transparent , colored etc. suitable pigments are added in the process of manufacturing of plastic material to get these different properties. So , these will give good appearance to the structure and makes it attractive.
Chemical Resistance of Plastics
Plastics offer great resistance against chemicals and solvents. Chemical composition of plastics during manufacturing will decide the degree of chemical resistance. Most of the plastics available in the market offer great corrosion resistance. So , corrosive metals are replaced by plastic in the case of water carrying pipes , etc.
Thermo-plastic types of plastics can be easily reshaped and reused. But in the case of thermo-setting type plastics , it is not possible to reshape or remold the material.
Ductility of Plastics
Ductile nature of plastic is very low. When tensile stress is acting on plastic member they may fail without any prior indication.
Durability of Plastics
Plastics with sufficient surface hardness are having good durability. Sometimes , plastics may be affected by termites and rodents especially in the case of thermoplastic types , however it is not a serious problem because of no nutrition values in plastic.
Plastics are good electric insulators. So they are used as linings for electric cables and for electronics tools.
Any type of finishing treatment van be given to the plastics. Mass production of plastic particles with uniformity of surface finish is done by having technical control during manufacturing.
The resistance to temperature or fire for varieties of plastics considerably varies depending upon the structure. Plastics made of cellulose acetate are burnt slowly. PVC made plastics do not catch fire easily. Plastics made of phenol formaldehyde and urea formaldehyde are fire proof materials.
Fixing of plastic materials is so easy. We can bolt , drill or glued to fix plastic material position.