1 – What is the mechanism of UV aging of polymeric materials? 2 – Why the...

1 – What is the mechanism of UV aging of polymeric materials? 2 – Why the mechanical properties of polymers varies with processing technique? 3 – How the dynamic friction of composite depends on the filler’s nature?

Expert Solution

1. The mechanism of UV aging involves an attack on tertiary carbon bonds in the chain structures of polymers. Free radicals are formed as a result of this attack which then react further with oxygen in the atmosphere producing carbonyl groups in the main chain. The effect of all this on the external surfaces of products includes discolouring and crack formation.

2. Mechanical properties of polymers varies with processing techniques because of change in temperature going from glass-like brittle behavior at low temperatures to a rubber-like behavior at high temperatures.

3. The addition of a filler in the form of a particulate can offer more resistance to the wear loss of the composites.

samet mamat answered 2 years ago

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