substituting degree
1.The mass ratio of cellulose,sodium hydroxide,and chloroacetic acid was 1∶1∶1.7.Cellulose was alkalified at 30~40℃ for 60min and etherified at 70~75℃ for 120~150min in the 90% ethanol. Viscosity of CMC was above 500 mpa·s. Substituting degree and available composition were>65% and >85% respectively.
2.The mol ratio of cellulose to sodium hydroxide to chloroacetic acid is 1∶3.7∶1.9.Celluloses were alkalified at 35℃ for 60min and etherified at 70℃ for 150min in the 90% ethanol. Viscosity of CMC is above 500mPa·s. Substituting degree and available composition are>65℃ and >85% respectively.
3.Carboxymethyl celluloses were prepared from bagasse fibers via oxidation (oxidant:H?2O?2), alkalization and etherification (catalyst:KI/NaAc) in the solution of 95% ethanol. The available component and the content of chloride of CMC are 85%～95% and <3%, the substituting degree and the viscosity of CMC being 0.65～0.80 and 500～800 mPa·s.
4.Based on the information of trainee providing by Qingniao information center of Beijing University,the author analyzed the situation of curriculum substituting from degree,speciality and employment,maintain the curriculum of ACCP be suit to the teaching for secondary specialized school and associate college degree,and vocational training of IT for trainee of non-computer speciality,then provide a path of vocational profession development of IT talents.
