Effects of succinic acid cross-linking and mono-phosphorylation of oxidized cassava starch on its paste viscosity stability and sizability

Oxidized cassava starch (OCS) was cross-linked with succinic acid (SA) and then phosphorylated with sodium tripolyphosphate to improve viscosity stability and usability of OCS for warp sizing. The level of cross-linking (LCL) and the degree of substitution (DS) of the phosphorylation were determined according to the stability, water dispersibility, adhesion-to-fibers, desizability, aerobic biodegradation, and film properties of the cross-linked and phosphorylated OCS. The cross-linking exhibited significant effects on the stability, water dispersibility, adhesion, film properties, and desizability, but was less sensitive to the biodegradation. The phosphorylation after cross-linking not only showed active effect on the usability, but also did not exhibit any adverse influence upon the stability. Suitable LCL and DS values resulted in stable viscosity, strong adhesion-to-fiber, tough starch film, and good desizability. Low LCL and DS could be employed to enhance the stability and improve the usability of OCS for warp sizing. Based on the stability and usability, the LCL and DS values were recommended to be 1 cross-link for 370-590 AGU units and 0.038, respectively.