聚丙烯酸脂高吸水交联小球的制备与表征

Preparation and characterization of crosslinked polyacrylate with high water-absorbing rate

采用反相悬浮法、氧化还原引发体系,合成了直径达毫米级的聚丙烯酸钠吸水小球.应用FT-IR证实了小球的化学结构,用DSC研究了交联剂用量对小球玻璃化转变温度的影响.研究发现,m(氧化剂):m(还原剂)为1.0:1.2、用量为单体质量的1.0%、w(交联剂)为5%、w(油):w(水)为5～7、分散剂为单体质量的0.2%,搅拌速度为200～250r/min时,合成的小球粒径较大且均匀,粒径达2.48mm,吸水后的小球直径可达10mm左右.小球的玻璃化转变温度值随交联剂用量的增加而降低.

The little sphere of polyacrylate sodium with the diameter of millimeter grade is prepared using inverse phase suspension polymerization and with redox initiation system.The chemical structure of the little sphere is confirmed with FTIR.The influence of the dosage of cross-linking agent on the glass transition temperature of the little sphere is studied using DSC.It is found that,the prepared sphere has greater and uniform diameter,and the greatest diameter can reach to 2.48 mm when the mass ratio of oxidant to reductant is 1:1.2;the dosage of cross-linking agent is 1% of monomer mass,the mass fraction of the cross-linking agent is 5%,the mass fraction ratio of oil to water is 5～7,the mass of dispersant is 0.2% of monomer,stirring speed is 200～250 r/min.After the little sphere absorbs water,its diameter can reach to 10 mm.The glass transition temperature of the little sphere reduces with the increase of the dosage of cross-linking agent.