功能添加剂对石膏凝胶晶体生长习性影响的研究进展  

Influence of functional additives on crystal growth habit of gypsum gel

作　　者：耿佳芬 刘东辉[1] 李桦军[1] 

机构地区：[1]昆明理工大学化学工程学院,云南昆明650500

出　　处：《化工科技》2015年第2期67-73,共7页Science & Technology in Chemical Industry

摘　　要：二水石膏的结晶形态和晶粒大小从宏观上对石膏硬化体的凝结时间、稠度、吸水率、强度、耐水性等影响很大。缓凝剂能抑制石膏晶体晶核的形成和生长,导致晶粒变粗,延长石膏凝结硬化时间;煅烧会导致石膏晶体晶格发生畸变,化学激发剂可促进石膏晶体生长,提高硬石膏水化活性,形成的石膏晶体多呈柱状且晶体间搭接更紧密,使石膏强度增加;除有机硅防水剂外,其它防水剂均会在石膏晶体表面形成一层薄膜,使形成后的晶体细小、搭接紧密,从而提高防水性能;不同减水剂对石膏晶体生长的影响各不相同,但成形石膏晶体之间的搭接均变致密,降低了水膏比。Crystal morphology and grain size of dihydrate gypsum have a great influence on macro- properties of gypsum sclerotium, such as setting time, consistency, water absorption, strength, water resistance, etc. The addition of retarder can inhibit the formation and growth of gypsum crystal nucleus and lead to the grain coarsening and prolong gypsum condense sclerosis. Crystal lattice of gypsum could be distorted by calcination, the anhydrite hydration would be promoted by adding chemical a- gent, thereby the gypsum crystal growth accelerated, the formed gypsum crystals take the columnar joints and space between the crystals change-and closer to increase the strength of gypsum. Besides or- ganosilicon waterproofing agent,the gypsum crystal surface will be covered with a layer of thin film when other waterproofing agent was added, it makes the crystal become smaller and the gypsum crys- tal overlap closely and the waterproof properties improve greatly; The influence of gypsum crystal growth is not identical while different water reducing agents was added, but overlap among the formed gypsum crystals all becomes dense,reducing the ratio of water and gypsum.

关 键 词：石膏晶体 缓凝剂 激发剂 防水剂 减水剂 

分 类 号：TQ177.3[化学工程—硅酸盐工业]