Poly , molecular Polyethylene, chain flexibility compared

Compared to traditional materials, especially metals, organic polymers show high sensitivity to temperature [1-3]. Most importantly, they exhibit very low softening points, which is attributed to the intrinsic flexibility of their molecular chains. Thus, whereas most metals do not soften appreciably below their melting points, which maybe 1000°C or higher, many polymers commonly used as plastics such as polyethylene, polystyrene, and poly( vinyl chloride), soften sufficiently by about 100°C to be of no use in any load-bearing applications. 

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