Effect of amylopectin content on pasting behavior and crystallization of corn starch size

Amylopectin was added into corn starch and thus obtained a mixed size for textile.Rapid Visco analyzer(RVA) and X-ray diffraction(XRD) were used to study the effect of different amylopectin contents on the rheological behavior and crystallinity of the corn starch size.The results indicated that with the increase of amylopectin content,the peak viscosity,valley viscosity,final viscosity of the corn starch size decreased gradually,the time to reach the peak value of the size viscosity was shortened,and attenuation coefficient and reversion coefficient decreased gradually.It means that addition of amylopectin facilitated the pasting and stablity of the size and improved the gluing.Meanwhile,the crystallinity of the mixed starch films and intensity of 2θ=5.8° decreased,but the crystallite dimension inceased with the increase of amylopectin content.