Wetting, pore structure, and liquid retention of hydrolyzed polyester fabrics

This study investigates the contributions of surface wetting and pore structure to liquid retention of fibrous materials using regular and microdenier poly(ethylene terephthalate) (PET) fabrics as the porous media. Varying surface wetting contact angles and pore structures are produced by hydrolysis of these PET fabrics using aqueous sodium hydroxide. Increasing levels of weight loss, porosity, and thickness reduction are observed with increasing hydrolysis temperatures (3N NaOH for 2 hours). The effects of hydrolysis temperature on wetting and pore structure are different for the two PET fabrics. Varying lengths of hydrolysis time (3N NaOH at 55 degrees C) also impose different effects on wetting and the pore structure of the microdenier fabric. With considerably varied wetting contact angles and pore structure, water retention of all PET fabrics is inversely related to water wetting contact angles. Data on hydrolysis of regular and microdenier PET fabrics show that improved water wettability plays a primary role in increasing water retention of these hydrophobic fabrics. Pore size distribution and pore connectivities can be limiting factors in liquid retention of hydrolyzed PET fabrics with modified wetting properties and porosity.