Absorción de líquidos en una resina epoxi inmersa en diferentes soluciones de limpieza

Abstract

The sorption of the epoxy network Diglycidyl Ether of Bisphenol A (BADGE n=0)/ isophorone diamine (IPD) immersed in basic solutions of sodium hydroxide, potassium hydroxide and sodium hypochlorite has been studied at different temperatures (25 and 45º). Because these materials can require a periodic cleaning, it is important to study the effect of the absorption of the cleaning habitual products and the chemical attack that they may cause on the materials. For the polymer immersed in sodium hydroxide, and in potassium hydroxide the liquid uptake increases with the increase in temperature. In contrast, the system immersed in sodium hypochlorite behaves in a different way since the liquid uptake tends to decrease as the temperature rises. This is because the volume occupied by the hypochlorite ion is larger and, when the molecular movement increases with increase in temperature, there are less microvoids for the liquid uptake. The diffusion at different temperatures shows a typical Fickian behaviour. The effects of liquid uptake above the glass transition temperature (Tg) have been studied at 25 and 45ºC. The material plasticization is higher at 45ºC for the systems immersed in sodium hydroxide (NaOH) and in potassium hydroxide (KOH). However, for the polymer immersed in sodium hypochlorite (NaOCl) the behaviour is the opposite because this ion occupies a much larger volume.