Page 38 - Curriculum Visions Dynamic Book

Vulcanising rubber
Vulcanising is the addition of sulphur to rubber. American inventor Charles Goodyear discovered the vulcanising effect of sulphur by chance in 1839 when trying to find an improved form of rubber.
Rubber is a polymer, that is a material
made of long chains of subunits called monomers. The rubber is soft and elastic because the chains of atoms move relatively freely across each other. In the process of heating rubber with sulphur, the sulphur atoms bond with the chains of rubber,
linking one chain to another. This makes it harder for the chains of rubber to move against each other and the result is a stronger material.
Vulcanised rubber does not soften as it is heated in the way that natural rubber does and so can be used for tyres and other applications where durability and strength is important.
An extreme form of vulcanising causes so many sulphur atoms to link together the rubber chains that the material becomes
a solid. This solid is called ebonite.
Also...
Sulphur atoms are found in human fingernails, where they crosslink the proteins to form a rigid material. So when you look at your nails, you are looking at a natural form of vulcanising.
 A vulcanised rubber hammer can be used for applying soft blows to steel panels, for example when beating out dents from damaged vehicle bodywork.
3
38
38
8