AKD专用高分子表面活性剂的性能研究

设计并合成了一种高分子表面活性剂,用FTIR、DSC、GPC分析手段研究了高分子表面活性剂的分子结构,并对其表面张力进行了测定。测试结果显示,4种单体都参与了共聚反应,无均聚物存在,高分子表面活性剂的重均分子量为58 536,数均分子量为16 812,多分散性系数为3.48,说明相对分子质量(简称分子量)的分散程度较小。温度为25℃时,高分子表面活性剂的CMC为0.8 mmol/L,γCMC为50.1 mN/m。当m(高分子表面活性剂)/m(烯酮二聚体)=0.23时,可制备出稳定的烯酮二聚体(AKD)乳液,且该AKD乳液质量占绝干浆质量的0.13%时,浆内施胶度可达200 s以上。用马尔文纳米粒度及Zeta电位分析仪测定出AKD乳液的平均粒径为574.4 nm,Zeta电位为11.16 mV。通过TEM观察,AKD乳胶粒子在高分子表面活性剂的包裹下呈核壳结构,并且形成水包油乳液。该高分子表面活性剂具有良好的表面活性与应用潜力。

Study on Property of a Polymeric Surfactant of AKD Emulsion

The polymer surfactant was designed and synthesized dedicated to the AKD emulsion.The structure of the polymer surfactant is characterized by FTIR、DSC and GPC,and the surfactant tension was measured by the surface tension method.The results indicate that four monomers are copolymerized very well and have no homopolymer existing,and the weight-average molecular weight is 58 536,the number average molecular weight is 16 812,the polydispersity coefficient is 3.48,so the polymer surfactant has a narrow molecular weight distribution.The CMC and γ_(CMC) was 8×10~(-4) mol/L and 50.1 mN/m respectively at 25 ℃.The AKD emulsion was relatively stable when m(polymeric surfactant)/m(AKD)was 0.23,and the internal sizing value is more than 200 s when the emulsion solid amount was 0.13% of the absolute dry pulp content.It was found that the average diameter and the Zeta potential of the AKD emulsion is 574.4 nm and 11.16 mV respectively by the Malven nanometer particle-size and the Zeta potential analyzer.The AKD particle wrapped by polymeric surfactant shows the core-shell structure,which was observed by TEM,and formed O/W emulsion.The polymer surfactant might be an excellent surfactant for practical use.