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InterviewSolution
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What is vulcanization and when it is done? |
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Answer» Solution :Vulcanization is a process in which the natural rubber is heated with sulfur to convert the SOFT, tacky thermoplastic MATERIAL to a strong, temperature stable material. The physicochemical change ARISES out of cross-linking of unsaturated hydrocarbon chain of polyisoprene with sulfur. During the vulcanization, inter- molecular thioetherification of polyisoprene with sulfur takes PLACE. The percentage of S used is 1-3, time is 3 mins at `150^(@)C` and only about 0.2% unsaturation is lost. Vulcanization is carried out after shaping the article. The shaping is DONE with raw rubber compounded with S and other ingredients such as accelerators, antioxidants, fillers, etc. |
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