两性羧酸类接枝共聚物混凝土超塑化剂的制备与性能评价

从羧酸类接枝共聚物外加剂吸附作用机理和两性聚电解质溶液理论着手,设计和合成了一种掺量低、饱和点高、减水率高、增强效果好的两性羧酸类接枝共聚物超塑化剂.当超塑化剂掺量为02%时,减水率达到30%;掺量为0.4%时,减水率高达40%,增大掺量,减水率可以进一步提高.无论是早期或中后期强度增长都比较稳定,在该外加剂掺量为水泥用量的0.30%,每立方混凝土仅采用390 kg的低水泥用量就可实现C80强度等级混凝土的配制.

Synthesis of amphoteric carboxylic acid-based graft copolymer superplasticizer for concrete and its property evaluation

Based on adsorption mechanism of carboxylic acids graft copolymer admixture and polyampholyte solution theory,an amphoteric carboxylic acid-based graft copolymer superplasticizer with low content,higher saturation point,high water reduction rate,and better reinforcement was designed and synthesized.When the content of superplasticizer is 0.2%,water reduction rate reaches to 30% that can be up to 40% when the content of copolymer is 0.4%.The water reduction rate will be further improved with increasing dosage.The strength increases stably no matter whether it is at early stage or at middle late stage.The concrete with C80 strength grade can be manufactured by using only 390 kg low grade cement/m3 concrete,when the content of superplasticizer is 0.30% of the cement amount.