| Natural wood powder F691 was carboxymethylated under microwave irradiation in order to increase its water solubility. The effects of reaction factors were investigated, such as the mass of chloroacetic acid (MAC) and NaOH, power of microwave irradiation, reaction time. The optimal conditions for the reaction were determined as:F6913 g, sodium hydroxide 1.4 g, chloroacetic acid 1.0 g, reaction time 50 min under microwave irradiation power of 500 W. The anionic charge concentration of the modified products could reach 3.523 mmol/g. The result also indicated that the degree of substitution (Ds) will be improved further by adopting microwave irradiation during the procedures of alkalization and etherification.The influence of stability of inverse emulsion including carboxymethylated nature powder granule were investigated. The inverse emulsions were prepared with a mixture of two kinds of nonionic surfactants (span-80 and op-10) as the emulsifier, liquid paraffin as oil phase, hydrophilic monomer AM and nature powder as aqueous phase. The effects of HLB value and concentration of emulsifier, aqueous phase volume percentage, the mass of nature powder granule, pH value, and temperature on stability of emulsion were investigated. The results show that, mass of nature powder and pH value has small influence on stability. The optimal conditions for steady water-in-oil emulsion are HLB of emulsifier 7.36, concentration 0.03g/mL in oil phase, aqueous phase volume percentage<60%, temperature low than 60℃.The present paper reports the grafting copolymerization of acrylamide onto carboxymethylated nature powder by free radical W/O polymerization using Ce4+-K2S2O8 redox system in the N2 atmosphere. The effects of reaction variables such as the time, temperature, and monomer, carboxymethylated nature powder and initiator concentrations on these parameters were investigated. Under the optimal conditions, the polymerization conversion ratio, the grafting ratio and the grafting efficiency were respectively 97.7%, 576.2% and 98.2. FTIR spectroscopy and 1H-NMR has given proof of grafting copolymers, and their molecular and thermal stability has been characterized.This study emphasized the application of grafting copolymer of CC-Na-g-PAM as strengthening agent of pulp. The results showed that the strength of pulp was improved when added CC-Na-g-PAM, it could obtain good effect in ONP (old newspaper pulp).The optional conditions were:mass of copolymerl.Og, percent of grafting 452.0%, reaction time was 6min. The tensile index, tear index and burst index could improve 30.30%,16.69% and 28.12%.
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