An analytical approach to study the loading behavior of hollow fibers under negative pressure and atmospheric pressure

Hollow fibers have been widely used as important components of membranes for drug delivery in the medical field. However, their usages in environmental and agricultural aspects have not been commonly unearthed. In our previous research, a new drug delivery system was established by utilizing hollow fiber as a carrier to convey medical substances in different phases, respectively. Our current research aims to expand the application of hollow fibers apart from medicine. In this study, the loading efficiency of the liquid under standard atmospheric pressure (nonvacuum) and negative pressure (vacuum) were further examined to achieve a higher loading system. The physical properties and the loading abilities of the three types of hollow fibers including original short crimped fibers, fibers from roving yarns, and fibers from spun yarns were studied and discussed. In-depth investigations of loading efficiency, wicking performance, water absorption, and thermal conductivity were conducted. Higher loading efficiency was observed by adopting the method of vacuum under negative pressure resulting from all experiments of which the result was at least 15 times higher than the nonvacuum-loaded methods. It was also at least 0.25% greater in moisture content, almost two times larger in the water absorption rate for yarn samples, and 35% higher for fabric samples. The differences in thermal conductivity within the two conditions were 0.00016 W/cm°C. Using the vacuum approach can improve the overall performance of precise liquid loading, increasing the efficiency and thereby reduce the production costs. It is believed to bring high-value advantages in agricultural aspects such as for sustainable pest control and crop growth.