Answers

2015-03-31T15:51:07+05:30
in toothbrush  not choose same type of plastics to make handle and bristles because bristles are used to clean our teeth and so it must be a type of smooth so not injured our gum but handles of toothbrush must be strong and tough so that it can give some grip and resist our efforts on it. 
for bristles 
thermoplastic type plastic are use 
and for handle 
thermosetting type plastic is use
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