Abstract: Synthesis technology and property of hydroxypropyl starch by using potato starch as raw material, propylene oxide as etherization reagent and sodium hydroxide as catalyst, were studied in this paper. The effects of some factors such as reaction time, amount of propylene oxide, reaction temperature and amount of sodium hydroxide on substitution degree of hydroxypropyl starch were investigated. It showed that molar substitution degree of hydroxypropyl starch was affected by the amount of sodium sulfate, its increase with the increase of reaction time, the amount of propylene oxide, the reaction temperature and the amount of sodium hydroxide. The spectrophotometer method was used for assaying the molar substitution degree of hydroxypropyl starch.

Key words: potato starch, hydroxypropyl starch, etherization, synthesis technology, property