程序降温反相悬浮技术制备球形纤维素珠体

以纤维素/N-甲基吗啉-N-氧化物(NMMO)/H2O溶液为原料,用NMMO法,通过程序降温反相悬浮技术制备出球形纤维素珠体,并进行制备工艺的优化实验和纤维素珠体的性能检测。实验结果表明,以10#变压器油为分散相,油水体积比V(油)∶V(水)=4∶1,m(复合型分散剂L-1)∶m(纤维素/NMMO/H2O溶液)=15∶100,在300r/m in的搅拌速度,可制备出粒径分布均匀的球形纤维素珠体,此时均一系数K=1.216。所制备的纤维素珠体的w(H2O)=74.0%,比表面积为215.6 m2/g,孔度为81.2%,湿视密度为0.63 g/mL,湿真密度为1.21 g/mL。在酸浓度或碱浓度为0.1~6.0 mol/L,随着酸浓度或碱浓度的增高,纤维素珠体的质量损失率递增,分别为0.1%~12.4%和0.8%~28.8%。

Preparation of Spherical Cellulose Beads by Sequential Cooling Reversed Phase Suspension Technique

The cellulose/NMMO/H_2O solution was used as the raw material to prepare the spherical cellulose beads by adopting the NMMO method and sequential cooling reversed phase suspension technique.Spherical cellulose beads with uniform particle size(uniformity coefficient 1.216) were obtained by using 10~# transformer oil as the disperse phase under such conditions as volume ratio of oil to water 4∶1,mass ratio of compound dispersing agent L-1 to cellulose/NMMO/H_2O solution 15∶100 and mixing speed 300 r/min.The moisture content of the prepared beads was 74.0%,the specific surface area was 215.6 m~2/g,the porosity was 81.2%,the bulk density was 0.63 g/mL and the true density was 1.21 g/mL.Moreover,the spherical cellulose beads had satisfactory acid-resistance and alkali-resistance.The mass loss of the spherical cellulose beads increased with increase in acid or alkali concentration in the range of 0.1 to 6.0 mol/L,the mass loss being 0.1%～12.4% and 0.8%～28.8%,respectively.