纸面石膏板生产中减水剂适应性问题的研究

摘要

从纸面石膏板生产中减水剂类型与石膏体系存在适应性问题的实际情况出发,选择了3类目前应用较多的减水剂:木质素类、萘系和聚羧酸系减水剂.在满足生产工艺要求的基础上,系统研究了它们对建筑石膏的凝结时间、强度、水化进程的影响规律,并进行了水化后石膏晶体形貌分析.结果表明,萘系减水剂与建筑石膏的适应性最好,既可提高产品质量,又可有效降低石膏拌合用水量,起到节能降耗的目的；聚羧酸系减水剂减水率高,但有缓凝效果,不利于石膏板的生产,且其适应性随生产厂家不同变化较大；木质素类减水剂与石膏体系的适应性较差,且染色严重.%According to the actual situation there are poor adaptability between water reducing agents and gypsum in the production of plaster board, three types of water-reducing agent are chosen in this subject: lignin. Naphthalene and polycarboxylate. Based on the requirements of the production process * effects of three different types of water-reducing agent on setting time, strength,hydration process of the building plaster have been studied systematically,and the morphology of the gypsum crystals have been analyzed after the gypsum hydrated. The results show that the adaptability of naphthalene superplasticizer with gypsum is the best in production. It not only can improve the product quality, but also can reduce the plaster mixing water, playing the role of saving energy. Water reducing rate of polymer superplasticizer is the highest, but it has retarding effect which is not conducive to the gypsum board production, and its adaptability vary greatly with different manufacturers. There is poor adaptability between lignin and gypsum system, and the phenomenon of severe staining appeared.