甜菜碱淀粉的制备及性能研究

Preparation and properties of betaine starch

以木薯淀粉、十二烷基二甲基甜菜碱(BS-12)为主要原料,采用水溶液法制备了甜菜碱淀粉。采用红外光谱(FTIR)、扫描电镜(SEM)、偏光显微镜(PL)、X-射线衍射(XRD)对其结构进行表征。结果表明,甜菜碱淀粉被成功制备,反应不仅发生在淀粉颗粒的无定形区,也发生在结晶区,且产生新的晶体结构。通过表面张力探讨甜菜碱淀粉在不同浓度、温度、pH和不同盐条件下的表面活性,及其与传统表面活性剂的复配性能,并研究其乳化性能和起泡性能。结果表明,甜菜碱淀粉临界胶束浓度3 g/L对应的表面张力为30.1 mN/m,饱和浓度10 g/L对应的表面张力为25.8 mN/m,在温度25~65℃、pH=7~12范围内均具有较高的表面活性,耐盐性能优良,乳化性能好,泡沫稳定性高,与传统表面活性剂兼容性好。

Betaine starch was prepared by aqueous solution with cassava starch and dodecyl dimethyl betaine(BS-12)as main raw materials.Its structure was characterized by infrared spectroscopy(FTIR),scanning electron microscopy(SEM),polarizing microscope(PL)and X-ray diffraction(XRD).The results showed that betaine starch was prepared successfully,the reaction occurred not only in the amorphous region of starch particles,but also in the crystalline region,and the new crystal structure was produced.The surface activity of betaine starch at different concentration,temperature,pH and salt conditions was investigated by surface tension test,and the compound performance of betaine starch with traditional surfactants was investigated.The emulsifying and foaming properties of betaine starch were studied.The results showed that the critical micelle concentration of betaine starch is 3 g/L,the surface tension was 30.1 mN/m,and the saturation concentration is 10 g/L,the surface tension is 25.8 mN/m.Betaine starch has high surface activity in the temperature range of 25℃to 65℃and pH 7 to 12.Betaine starch has excellent salt resistance,good emulsification performance,high foam stability,good compatibility with traditional surfactants.