On the two mechanisms of the effect of physically aggressive media on the mechanical properties and structure of polyamide-6

Evolution of the Nanoporous Structure of High-Density Polyethylene during Drawing in Supercritical Carbon Dioxide

“…The temperature increase has resulted in the decrease in the amount of the adsorbed gas and, hence, has reduced its crazing action. Other reports 28,29 have marked that the crazing is not observed when the relative gas pressure is below the threshold value of p/p s = 0.2−0.25. It has been demonstrated that the threshold gas pressure corresponds to the appearance of the gas monolayer adsorbed on the planar surface.…”

“…Using the Tomson−Kelvin equation, it has been shown that surface defects at which the gas condensation starts are about 2.2 nm in diameter. 29 The use of a gas in the supercritical state can enhance its activity as the crazing agent far from the condensation point. It is known that the physicochemical properties of supercritical fluids are significantly changed depending on the temperature and pressure.…”

“…It has been suggested that the adsorption action of the gas requires its condensation in the forming pores, that is, the appearance of the liquid phase. Using the Tomson–Kelvin equation, it has been shown that surface defects at which the gas condensation starts are about 2.2 nm in diameter …”