| Corn starch enzymatic hydrolysis was carried out by using α-amylase, after enzymatic treatment, the starch was further oxidized by TEMPO oxidation system, then, the product was used for surface sizing. The experiment results indicated that the most efficient reaction condition of TEMPO system oxidation was as follows, pH value was 9.5, temperature was 5℃, reaction time was 2.0 h, dosage of TEMPO was 1.0 mg/g and the dosage of NaClO was 2.00 mmol/g. In this condition, the modified starch had 5.06% of the carboxyl contents. Using the starch as surface sizing agent and with the sizing dosage of 4 g/m2, tensile strength and surface strength of sized sheet rose by 51.6% and 334% compared with the sheets without sizing. |
