Natural Plant Straw Preparation Of The Gender Of Cellulose

A novel amphoteric cellulose graft copolymer (PCGD) using wheat-straw and maize straw as synthetic materials were prepared in this work. The straw materials were treated with Steam-Explosion firstly, secondly they were cooked in chemical agents repeatly to get well-purified cellulose, then the straw cellulose were used to prepared carboxymethyl cellulose (CMC) possessing wonderful water-solubility and high degree of carboxymethyl substitution(DS). At last we gained grafted copolymer (PCGD) of methacrylate-ethyl trimethylammonium chloride (DMC) and CMC with potassium persulphate (K2S2O8) and hyposulphite (Na2S2O3) as initiators.The results showed that SE treatment can not only destroyed the molecular structures of cellulose but also effectively separated cellulose from other components. Compared with other methods, SE treatment can help to improve cellulose's purity effectively. We also found straw cellulose can get a better effect if SE pressure is 2. 5 MPa and keep the pressure about 120 seconds.The optimum techniques preparing CMC and the influences made by some factors , such as materials and SE treatment, were also studied in this work, we affirmed that the ultimate production are CMC by infrared spectrum (IR) analysis. The experimental results indicate that chemical agents can easily arrive the interior of cellulose after going through SE treatment and the degree of carboxymethyl substitution can easily arrive at 0.8 even in the relaxing techniques condition. So the straw materials can serve as the producer's goods of CMC simply.In this paper, the graft reactions of CMC and DMC and the characteristic of PCGD water solution were studied at large. The existence of amphoteric cellulose also were affirmed by IR analysis and Chemical Titration. The experimental results show that K2S2O8 / Na2S2O3 initiators system is very effectual to initiate CMC . The factors affecting the reaction were investigated in details, including the effectes of the initiator concentration, the ratios of the raw materials and temperature , and so on. At last we concluded that the neutral condition is suitable for grafting reactions, theoptimum reaction temperature is 40℃, the optimum ratio of initiator K2S2O8 andNa2S2O3 is 1:1, and optimum DS of CMC is 0.7-0.9. Besides, we also found that PCGD solution can resolve if we put inorganic salt in solution and show amphoteric characteristic. If the system acid of PCGD water solution varies continuously, there exist obviously isoelectric point(IEP).At last, the linkes between structural parameter and isoelectric point(lEP) also were studied in this work.