Synthesis and analysis of new humidity-controlling composite materials

摘要

Gypsum is a traditional building material.To improve the humidity-controlling properties of gypsum,we prepared a new type of humidity-controlling composite using the sol–gel method.Methods to determine the maximum equilibrium moisture content and speed of adsorption/desorption were subsequently applied to analyze the performance of the samples.The appearance and structural properties of the samples were characterized by scanning electronic microscopy(SEM).The experimental results show that the humidity-controlling gel with added LiCl exhibits high moisture storage and that the equilibrium maximum moisture content is 5.652 g/g at a 75.29% relative humidity(RH).A mass ratio of LiCl/sol = 0.15 is demonstrated to be appropriate for the preparation of the new humidity-controlling composites.A coarse network with tiny pores is observed on the surface of the new humidity-controlling composites,and this pore network provides sufficient space for moisture adsorption.