Determination of the influence of structure and thermal history on the dynamic mechanical properties of high density polyethylenes

摘要: This work is aimed at determining the influence of molecular weight distribution, branch content, and thermal history on dynamic mechanical properties four high density polyethylenes. Molecular segregation as a function crystallization conditions has been measured by means differential analysis, whereas infrared spectroscopy allowed us to relate structural changes introduced use different with both properties. The α-relaxation most affected transition treatments. plays an important role in behavior when amount segregated material big enough shield effect due isothermally thickened crystals. presence degree brings about asymmetry peak well detectable reorganization factor (which defines order within system) obtained spectroscopy. supermolecular structure found not affect β-relaxation depends λ-relaxation remains constant regardless characteristics conditions.