화학공학소재연구정보센터
KAGAKU KOGAKU RONBUNSHU, Vol.30, No.1, 91-94, 2004
Control of polymer content profile within dried porous material wetted with aqueous polymer solution by sequential drying with microwave and convection
Sequential drying with microwave and convection was examined in a packed bed of glass particles wetted with aqueous polyvinyl alcohol solution. Samples with a higher initial moisture content than the critical moisture content gave a flat profile of polymer content except near drying surface after being dried. Such a profile had not been observed in the case of convective drying, in which minimum polymer content appeared at the bottom of the dried sample, or in the case of convective-conductive drying, in which minimum content appeared in the center. The profile was the result of enhanced evaporation of water inside the wet sample by the microwave. This sequential drying was effective for giving a new profile of polymer content within the dried sample.