多孔酚醛树脂微球的制备

Preparation of Porous Phenolic Resin Microspheres

采用水相悬浮聚合法制备了多孔酚醛吸附树脂,通过正交试验探讨了致孔剂、酚醛比、催化剂、搅拌速率、温度、分散剂等对产物产率、产物粒径分布的影响,得到多孔酚醛树脂微球最优制备工艺条件:苯酚与甲醛占总体系质量14.5％,且n(甲醛)∶n(苯酚)=1.2∶1；催化剂为25％ NaOH溶液,用量0.732 g；交联剂六次甲基四胺(HMTA)用量0.6 g；分散剂聚乙烯醇(PVA),用量0.28 g；致孔剂十八醇添加量5 g,搅拌速率185 r/min;在95 ～97℃下预聚45 min,反应4h,酸固化30 min.制得的多孔聚合物微球产率高、粒径分布较窄、形态规整.以十八醇-甲苯混合致孔的酚醛树脂具有较高的产率(81.9％),且40～80目的微球占有率也高达97.2％.

A porous phenolic resin adsorbent was prepared with aqueous phase suspension polymerization technique.The effects of porogen,phenol-to-aldehyde ratio,catalyst,stirring rate,temperature and dispersant,etc.on product yield and product particle size distribution were studied in orthogonal tests,and the optimum porous phenolic resin microspheres preparation conditions were identified as follows:mass ratio of phenol and formaldehyde to the overall reaction system:14.5%,n(formaldehyde):n(phenol) = 1.2:1,catalyst:0.6 g of 25% NaOH solution,crosslinker:0.6 g of hexamethylenetetramine(HMTA),dispersant:0.28 g of polyvinyl alcohol(PVA),porogen:5 g of octadecyl alcohol,stirring rate:185 r/min,pre-polymerization temerature:95 to 97 ℃,reaction time:4 h,acid curing time:30 min.The yield of the porous polymer microspheres thus prepared was high,their size distribution was narrow,and their shapes were neat.The yield of the phenolic resin made porous with octadecyl alcohol and toluene was as high as 81.9%,and the 40-mesh to 80-mesh microspheres accounted for 97.2% of the total microspheres produced.