THE STUDY ON MECHANISM OF BINDER MIGRATION DURING COATING PROCESS

Binder migration during coating process and the mechanism of binder migration were studied in this paper. After the latex was tagged by osmium, the degree of binder migration was measured by energy-dispersive X-ray spectrometer. For the wet sample just after coating application, the real information of binder distribution was kept by quenching the sample in liquid nitrogen followed by freeze-drying. The results showed: under the condition of this research, binder migration occurred both in the process of coating application and drying.But the amount of binder migration occurred during coating application was much little than that occurred during drying. The mechanism of binder migration during the process of coating application was studied by force analyses. And one viewpoint was proposed that was binder migration was caused by Magnus force and Saffman force.