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Polymers — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryPolymers2 Marks
Question
To have practical applications why are cross links required in rubber?
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Answer

To improve upon physical properties of natural rubber, a process of vulcanisation is carried out. This process consists of heating a mixture of raw rubber with sulphur and an appropriate additive at temperature range between373K to 415k. On vulcanization, sulphur forms cross links at the reactive sites of double bonds and thus the rubber gets stiffened.

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