QUIZ 2

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1) Define:

a) Natural rubber (2 marks)– elastic hydrocarbon polymer which naturally occur as latex in the sap on the plants.

b) Synthetic rubber (2 marks) – artificially hydrocarbon polymer which act as elastomer and is made by a process known as polymerization.

2) Describe the rubber tapping process in order to produce rubber sheet. (6 marks)

Rubber tapping starts once the trees reach its maturity which is about 7 years. First, the tree is tapped using a chisel by shearing off the tree’s bark. The latex is collected in a small cup and collected frequently to prevent contamination. The latex is then brought to the nearest station. Ammonia is added as preservative into the rubber. It is continued by a process known as coagulation where formic acid is added. At the end of the process, solid rubber appears as a solid block. The rubber is initially rolled using a roller before it enters mangle machine for further rolling to make it thinner and also to squeeze out the water. Finally, the rubber is dried either using mechanical dryer or by traditional method of using smoke house. The white rubber sheet turns to golden brown rubber sheet. This rubber is sent to other rubber industries to make the end products.