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How Bakelite is prepared? |
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Answer» Bakelite is a thermosetting plastic (phenol-formaldehyde resign). It is used for making TV cabinets, telephone components, billiard ball, bearings, electrical goods etc. It is prepared by the polymerisation reaction between formaldehyde and phenol. In the formation of Bakelite, the reaction mixture is prepared by mixing formaldehyde with phenol with glacial acetic acid under fume hood. Some quantity of reaction mixture is taken in a beaker and placed on a white paper towel. 10 to 12ml of conc. Hydrochloric acid is added drop by drop by continuous stirring. On heating polymerisation begins, white precipitate starts appearing (60-55 degree C). On vigorous and constant stirring pink colour plastic forms (75 to 60 degree C). The reaction is very fast and heat of the reaction is also high |
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