Method for predicting long-term durability of resin composition for piping and olefinic polymer used for resin for piping

A method for predicting long-term durability of a resin composition for piping comprising:

• collecting data of the resin composition, the data comprising a content (wt %) of tie molecules, an entanglement molecular weight (Me), and a content (wt %) of a component having a mass average molecular weight (Mw) of 1,000,000 or more;
• and
• using Equation below to determine a value of long-term durability of the resin composition:
• Long-term durability predicted value of resin composition=a×(X)b×(Y)c×(Z)d [Equation]
• wherein, a=386,600, b=4.166, c=−1.831, and d=1.769, X, Y and Z represent, in the resin composition, the content (wt %) of tie molecules, the entanglement molecular weight (Me), and the content (wt %) of the component having the mass average molecular weight (Mw) of 1,000,000 or more, respectively, where X, Y and Z are used as dimensionless constants excluding their respective units.