| A new method of hemicellulose determination was established through multivariate chemometrics analysis software, which in ways to help us analyze the impact of dissolved hemicellulose content on pulp physical properties, the impact of uromic acids to optical performance of the pulp was also discussed. Then, the modification of the core of corn stalks, which is hemicellulose-rich, was optimized and improved in order to explore the utilization pattern of the hemicellulose in pulp and paper field.The analytical method of the hemicellulose usually exists defects, such as using organic reagents regularly and operating intricately , although there are many ways to detect the content of hemicellulose. In this paper, a new determination method of hemicellulose that conveniently and without using organic solvents was established by the spectral measurement of a set of hydrolyzed standard sugar solutions by treating with concentrated sulfuric acid and a chemometrics software. A part of hemicellulose which can be detected using the former method have been removed from poplar wood Alkaline Peroxide Mechanical Pulping by xylanase treatment in order to analyze the impact of the hemicellulose content on pulp properties.The results showed that the dissolution of total sugar and reducing sugar increased with the increasing of enzyme dosage at a given range, so did the hemicelllulose. Also, the pulp's tensile index and burst index were decreased with the decrease of hemicelluloses in pulp, and the greatest decrease reached 21.88% and 20.81% respectively comparing with the blank pulp, Contrarily, opacity and tear index were decreased with the reduction of hemicelluloses, and the greatest increase reached 21.88% and 20.81% respectively. The uronic acid added experiment showed that the kappa number of the plup increased by adding uronic acid which maybe indicated that the carboxyl group played a role in the determination of kappa number and the brightness stability.For there exists defects with the extraction process of hemicellulose, such as high extraction cost, modest extraction efficiency and extract purity, as well as difficult separation, the core of corn stalks added to the pulp directly after modification was also studied in this paper. The optimum condition of the key modification process was determined using response surface analysis method: processed at 57.59℃for 5.49 hours with 6.48% of the hydrogen peroxide dosage. But adding a large quantity of the core of corn stalks in the pulp brings to a low drainage rate. In order to solve this problem, a new attempt was carried out with different modification methods, and the result showed that the modification effect of the core of corn stalks was improved significantly through adding the oxygen-alkali process. Plackett-Burman design was used to evaluate the effective degree of factors before the optimization of the main factors of oxygen-alkali process was carried out by response surface analysis method.Mechanism about how the oxygen-alkali process affects modified core of corn stalks to improve pulp strength performance have been studied by SEM and FTIR spectrograms. SEM shows that there is no block or a group-like kind of material exsist in the modified core of corn stalks after the oxygen-alkali process, which means that the modified core of corn stalks was easier to flow and permeate between fibres. FTIR spectrograms analysis shows that the hemicelluloses in core of corn stalks were oxidized and some groups changed,such as–OH (become–COOH or–CHO)which can reinforce fiber bonding and improve paper's strength performance, especially adding the oxygen-alkali process.
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