关于主链分子结构对聚碳酸超塑化剂吸附,分散和水合的影响的研究
Yunhui Fang1,2,3, Zhanhua Chen1, Dongming Yan3
1KZJ New Materials Group Co., Ltd., Xiamen 361101, China.
Materials (Basel, Switzerland)
|July 14, 2023
概括
合成和测试了具有多种结构的聚碳酸 (PCEs). 带有硫和碳基组的PCE增强了水泥吸附率,而烯胺组改善了分散和延缓水解.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 物理化学 物理化学
背景情况:
- 聚碳酸乙烯 (PCE) 是混凝土技术中至关重要的超塑性化剂.
- 了解PCE的结构属性关系对于优化水泥材料性能至关重要.
- 功能组对PCE吸附,分散和水化阻滞的影响需要详细研究.
研究的目的:
- 合成具有多种主要链结构的PCE,包括硫酸,烯胺和炭基.
- 研究这些合成的PCEs对水泥颗粒的吸附行为,分散能力和水化阻滞效应.
- 阐明特定功能组对PCE在水泥系统中的性能的影响.
主要方法:
- 使用水溶液自由基聚合来合成PCEs.
- 使用红外光谱学和凝染色学来表征分子结构.
- 用总有机碳分析,风力测量和异热微热量计来评估吸附,分散和水合性质.
主要成果:
- 对水泥颗粒的PCE吸附是一种由静电相互作用和结合驱动的自发物理过程.
- 硫酸和聚碳酸组加快了PCE吸附率,增加了平衡吸附,同时减少了初始吸附.
- 烯胺组增强了初始分散,降低了水泥泥的塑料粘度,并延长了水泥水化诱导期.
结论:
- 主链结构显著影响固系统中的PCE性能.
- 含有烯胺基组的PCE有效地提高了水泥泥的可加工性,并延迟了水化.
- 硫酸组的存在增强了吸附动力学,但对水泥水化有有限的减缓作用.
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