Techniques Research Of Preparation For Oxidized Potato Starch And Its Adhesives

The starch is a high-molecular compound, composed by α-D-glucose molecules, whichare attached by the gtlycosidic bond, and its molecular formula is (C6H10O5)n. The starchcontains the two kinds of amylose and amylopectin. The starch is a important kind of industrymaterial. Its advantages are inexpensive, rich, short maturity period and renewable. And it canbe decomposed compeletly without poison. However, the starch has some shortages due to itsmolecular structure. And the kinds aren’t enough, too. So we need to denature the starch inorder to utilize the starch.Oxidized starch is the starch oxidized by antioxidants in the medium whoes environmen-t is acid, alkaline or neutral. Oxidized starch has many advantages, such as good diaphaneityof glue, high solid containing, low viscosity, strong bond, good liquidity, not easily gelling,and so on. So it is widely used in the fields of paper, textile, food, and building.This research includes three parts: techniques research of preparation of the oxidized po-tato starch by potassium permanganate, the function studying of the oxidized potato starch inhelping washing and techniques research of preparation of the oxidized potato starch’s adhesi-ve.In the second part, through single-factor test and L9（3~4）) four factors and three levelsorthogonal test of the temperature and the quantity of sodium hydroxide, potassium permanga-nate and sulfuric acid, with the carboxyl content as the standard, the optimum conditions oxi-dation were obtained: starch25.00g, water37.5mL, the temperature25℃, the quantity ofpotassium permanganate0.24g, the quantity of sodium hydroxide0.125g, the quantity of sul-furic acid0.85ml, and the carboxyl content is up to0.4323%.In the third part, through the research on the four factors of pH, the temperature, calciumion concentration and binding time, we found that the optimum conditions of the calcium bi-nding ability of the oxidized potato starch with0.423~4%carboxyl content are: pH12, thetemperature40℃, calcium ion concentration4mmol/L,binding time20min, the calcium ionbinding ability is up to76mg/g. In the forth part, through the research on the four factors of the dosage of the potassiumpermanganate, the sodium hydroxide, the PVA and the dry casein，with the adhesive viscosity,the adhesive drying time and the adhesive bonding strength as the standard, the optimum cond-itions were obtained: starch25.00g, potassium permanganate0.20g, sodium hydroxide5.00g, PVA3.00g, the dry casein7.50g and a little boric acid and ethanol as the preservative, andthen the adhesive viscosity is79Pa·S, the adhesive drying time is2.6h, the adhesive bondingstrength is24Pa.