摘要
对硅碳白悬浮体做了系统工作。在含量较少的情况下呈牛顿型。含量达到一定程度后,产生三维结构,出现塑性体系。产生结构的固体含量与 PH 值有关。实验证明,在等电点(i,e,p.)附近结构最松驰。研究了水解聚丙烯酰胺(HPAM)对悬浮体的影响,发观在体系里的 HPAM 性能起主导作用,并破坏了原来硅碳白聚集体结构,呈絮凝体结构,并出现触变性。当高聚物在固体表面上一半时,具有最大动切力,即机械强度最高。同时产生最大触变性。聚丙烯酰胺的水解度较大时,体系出现了负触变性。
The rheological characteristic of aqueous silica dispersion was inve-tigated and regarded as a function of PH against the volume fraction ofailica.A gradual transition from Newtonian to pseduoplastic behaviorwas observed as the silica content was gradually increased.The plots ofηp versus the percentage of silica showed a rapid increase in ηpL abovea critical silica concentration,which was dependent on the PH of thedispersion.These results were explained in terms of the interaction bet-ween the silica particles and the size of the units formed.the preliminaryresults about the effect of addition of HPAM at PH=4 showed anincrease in yield value τ reaching a maximum at HPAM concentrationcorrsponding to 0.5 coverage.Moreover,the rheological results showedextensive hysteresis in shear stress-shear rate curves,indication ofthixotropy.The negative thixotropy behavior was further increased withhydrolyzed degree of HPAM.The results were related to bridgingflocculation and partially“restrained”by interaction of polymer moleculesby silica particles.
出处
《青岛化工学院学报（自然科学版）》
1992年第2期71-77,共7页
Journal of Qingdao Institute of Chemical Technology(Natural Science Edition)
基金
中国科学基金资助项目
