| 초록 |
ESCR(environmental stress cracking resistance) is the ability of a polymer to resist slow crack growth or environmental stress cracking, which is an important performance parameter for different applications of high density polyethylene (HDPE), from the blow moulding bottles up to the highly demanding applications like water and gas pipes. ESCR is influenced by molecular structure such as molecular mass, molecular mass distribution and SCB(short chain branch) and increases with increasing density of tie molecules. Huang & Brown's model has been used to theoretically predict density of tie molecules in the polymer. Generally ESCR testing methods are time consuming and tedious. The strain hardening modulus (SHM), measured by tensile experiment, provides even simpler and rapider method to assess slow crack resistance. In this study density of tie molecules and relationship between SHM and ESCR were investigated for different molecular structured HDPE. |
