Effect of modified maize starch binder on the quality of seed tape twisting

In order to improve the tensile strength and the accuracy of hill distance of seed tape, and to prevent seed dropping during the process of seed tape twisting and during the direct sowing, this paper proposed a new approach which brushed binder on the inclusive materials and developed a binder with modified corn starch. Experiment results showed that the influence of modified maize starch binder and its dosage and viscosity on the emergence rate of rice seeds was indistinctively. By means of quadratic regression orthogonally rotational combination experiment, the effects of dosage and viscosity of the modified corn starch binder on the tensile strength of the seed tape, the accuracy of hill distance and the pass rate of the quantity per hill were studied respectively, and then the corresponding mathematical model were established. By the method of multi-objective nonlinear optimization, parameters of dosage and viscosity of the modified corn starch binder were optimized, then the optimal parameters combination was found out as following: the dosage of binder was 80% and the viscosity was 7 792 mPa·s. Under this optimal conditions, the tensile strength of seed tape reached 18.84 N, coefficient of variation of drop-hill distance was 3.25%, and the pass rate of the quantity per hill got 91.05%. The results showed that brushing the modified corn starch binder on the inclusive materials played an important role in improving the seed tape tensile strength and the accuracy of hill distances during the process of seed tape twisting. Moreover, it had no influence on the emergency of rice seeds and environment. The results will offer an important reference to improve the designing of seed tape twisting machine.