外加剂对磷石膏基抹灰石膏性能的影响

利用煅烧低强磷石膏配制抹灰石膏,研究了粉煤灰、石粉、缓凝剂、纤维素醚、减水剂掺量等因素对抹灰石膏性能的影响。结果表明,填料总量不变条件下,粉煤灰、石粉掺量对抹灰石膏标准扩散度用水量影响较小,随着粉煤灰掺量的减小及石粉掺量的增加,抹灰石膏的凝结时间缩短、强度降低;随着缓凝剂掺量的增加,抹灰石膏的凝结时间以及初终时间间隔逐渐延长,强度降低;随着聚羧酸减水剂掺量的增加,抹灰石膏标准扩散度用水量降低,凝结时间延长,强度提高;随着纤维素醚掺量的增加,抹灰石膏标准扩散度用水量逐渐增大,凝结时间与初终凝间隔时间逐渐延长,抗折、抗压强度不断降低,而拉伸粘结强度不断升高。

The effect of additives on the properties of phosphogypsum-based plastering gypsum

In this study,the plastering gypsum was prepared by calcining low-phosphorus gypsum,and the effect of dosage of fly ash,stone powder,retarder,cellulose ether and water reducing agent on the properties of plastering gypsum was studied. The results show that the change of fly ash and stone powder has little effect on the water consumption of the standard diffusion degree of plastering gypsum under the condition of the total amount of filler being constant. With the decrease of the amount of fly ash and the increase of the amount of stone powder,the setting time is shortened,the strength is reduced;as the amount of retarder is increased,the setting time of the phosphogypsum-based plastering gypsum and the initial time interval are gradually extended,and the strength trend is lowered;With the increase of the amount of acid water reducing agent,the water consumption of the standard diffusion degree of plastering gypsum is gradually reduced,the setting time is gradually prolonged,and the strength is continuously increased. With the increase of the amount of cellulose ether,the standard diffusion water consumption of plastering gypsum gradually increasing,the setting time and the initial setting interval are gradually prolonged,the flexural and compressive strength is continuously decreased,and the tensile bond strength is continuously increased.