The effect of polyethylene glycol Mw 400 and 600 on stability of Shellac Waxfree

The effect of polyethylene glycol (PEG) having molecular weight of 400 and 600 on stability of shellac waxfree prepared by solvent-evaporation method was reported in the present paper. The stability of shellac was tested by life under heat at 125 °C for 10,30,90, and 180 minutes. It was found that that stability of shellac decreased with heating time at 125 °C. PEG400 gave the most stable effect of shellac for 30 minutes of heating, whereas at 90 minutes and above PEG600 gave the most effect of shellac stability as shown by insoluble solid test and FTIR. The WVTR showed that water vapour barrier properties of PEG600/shellac was beter than that of PEG400/shellac system.