How to prepare plastic

<div dir="ltr" style="text-align: left;" trbidi="on"> <h2 style="text-align: left;"> <span style="font-size: large;"> Plastic </span></h2> <span style="font-size: large;"> Plastics are synthetic resins which are rapidly becoming important in everyday life. These are classified into two types: </span><br /> <span style="font-size: large;"> Thermoplastics </span><br /> <span style="font-size: large;">Thermosetting plastics </span><br /> <br /> <h3 style="text-align: left;"> <span style="font-size: large;">Thermoplastics </span></h3> <div style="text-align: left;"> <span style="font-size: large;"> These are the plastics which can easily be softened when heated and become hard when cooled with a little change in their properties. When heated they melt and form a fluid which can be moulded into any desired shape and then cooled to get the desired product. Common examples are polythene, polypropylene, polyvinyl chloride etc. </span></div> <h3 style="text-align: left;"> <span style="font-size: large;">Thermosetting Plastics</span></h3> <div style="text-align: left;"> <span style="font-size: large;"> These are the plastics which undergo permanent change on heating. When heated they get highly cross linked to form hard, infusible products. Common examples are bakelite, melamine etc.</span></div> <h3 style="text-align: left;"> <span style="font-size: large;"> Methods of preparation and uses of plastics </span></h3> <h4 style="text-align: left;"> <span style="font-size: large;">Polythene</span></h4> <div style="text-align: left;"> <span style="font-size: large;"> It is prepared by the polymerization of ethjfrie under high pressure and in the presence of traces of oxygen (0.01 %) </span></div> <div style="text-align: left;"> <span style="font-size: large;"> nCH2 = CH2 ► —{-H2C— CH2)t- </span></div> <div style="text-align: left;"> <span style="font-size: large;">It is used in the manufacture of pipes, laboratory apparatus, bottles, buckets, toys and electrical insulators. </span></div> <h3 style="text-align: left;"> <span style="font-size: large;">  Polyvinyl chloride (PVC) </span></h3> <div style="text-align: left;"> <span style="font-size: large;">It is prepared by the polymerization of vinyl chloride (CH2=CHCI) in an autoclave PVC is used: in the manufacture of rain coats and hand bags. for artificial flooring. as a good insulating material for wires and other electrical goods. </span></div> <h3 style="text-align: left;"> <span style="font-size: large;">Polystyrene </span></h3> <div style="text-align: left;"> <span style="font-size: large;"> It is prepared by the polymerization of styrene in the presence of benzoyl neroxide. It is resistant to shock and chemical action. It is used for: making hot drink cups, toys, combs, etc. making radio and television bodies. Making tiles to be used in covering ceilings and floors. Teflon (Polytetrafluoroethylene) It is prepared by the polyemerization oftetrafluoroethylene. Pressure It is used in the manufacture of non-stick utensils. </span></div> <h3 style="text-align: left;"> <span style="font-size: large;">Bakelite</span></h3> <div style="text-align: left;"> <span style="font-size: large;"> It is prepared by the polymerization of phenol and formaldehyde. It is used for making combs, fountain pens, formica, tabletops and electrical goods. </span></div> </div>

How to prepare plastic

 Plastic   Plastics are synthetic resins which are rapidly becoming important in everyday life. These are classified into two types:   ...

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