2-羟基-3-丁氧基丙基淀粉的制备

以玉米淀粉为原料,丁基缩水甘油醚(BGE)为疏水化试剂,氢氧化钠作催化剂,水为溶剂,在较温和反应条件下合成了2-羟基-3-丁氧基丙基淀粉(HBPS)。考察了反应温度、反应时间、碱用量、水用量和BGE用量等因素对取代度和反应效率的影响,确定了最佳制备条件为:当n(BGE)/n〔淀粉葡萄糖单元(AGU)〕=0.615,m(H2O)∶m(AGU)=2∶1,n(NaOH)∶n(AGU)=0.5∶1,反应温度75℃和反应时间为5h,产品取代度MS=0.45,反应效率RE=73%。用IR、1HNMR、13CNMR对产物结构进行了表征。热重实验表明,疏水基团的引入可提高淀粉的耐热性能。

Preparation of 2-Hydroxy-3-butoxypropyl Starch

2-Hydroxy-3-butoxypropyl starches(HBPS) were synthesized by an environmentally friendly process using butyl glycidyl ether(BGE) as the hydrophobic reagent,water as solvent and sodium hydroxide as a catalyst.The reaction conditions were investigated and optimized.Optimum conditions were obtained as follows:n(BGE)/n(AGU)=0.615,amount of solvent was m(H2O):m(AGU)=2:1,amount of catalytic NaOH was n(NaOH):n(AGU)=0.5:1,reaction time was 5 h,reaction temperature 75 ℃,molar substitution(MS) of 2-hydroxy-3-butoxypropyl was up to 0.45,the reaction efficiency(RE) was 73%.The HBPS and corn starch were characterized by IR,1HNMR and 13CNMR.In addition,the TG result indicates that the hydrophobic modification can improve the thermal stability of starch.