在稀释溶液中由miktoarm星聚合物形成的聚合物的pH诱导的形态转变:一个介光学模拟研究
Zengwei Ma1, Gaiqin Liu1, Nan Hu1
1College of Science, Chongqing University of Technology Chongqing 400054 China redskywei@cqut.edu.cn.
RSC advances
|August 5, 2024
概括
我们使用DPD模拟来探索miktoarm明星聚合物的自我组装和pH响应行为. 聚合物臂的长度和pH值的变化决定了复杂结构的形成,如囊泡和小胞.
科学领域:
- 聚合物化学 聚合物化学
- 软物质物理学 软物质物理学
- 计算化学的计算化学
背景情况:
- 微星聚合物是复杂的宏分子,在纳米技术中具有潜在的应用.
- 了解它们的自我组装和对pH等外部刺激的反应对于设计先进材料至关重要.
研究的目的:
- 为了研究在中性溶液中miktoarm星聚合物 (μ-A(B(D)) C) 的自我组装.
- 在酸性环境中探索聚合物囊泡和小粒的pH响应行为.
- 阐明静电相互作用在形态转换中的作用.
主要方法:
- 消散粒子动力学 (DPD) 模拟被用于模拟聚合物行为.
- 研究了响应pH的手臂 (B) 和水友的手臂 (C) 长度对形态的影响.
- 响应pH的手臂的质子度调整以观察结构变化.
主要成果:
- 在中性溶液中,自组合的形态 (囊泡,盘状小,球状小) 通过臂长度来调节.
- DPD模拟显示了囊泡和小胞的动态进化路径 (核化,凝聚,生长).
- 响应pH的手臂质子化诱导从纳米盘转变为囊泡的纳米片和纳米丝带,以及类似虫的微粒,纳米片和纳米丝带的球形微粒.
- 静电相互作用影响对子离子分布,在纳米薄膜中形成六边形图案,在纳米丝带中形成替代分布.
结论:
- 聚合物臂长和pH值是控制miktoarm星聚合物自我组装和形态的关键因素.
- 该研究提供了关于聚合物聚合物的动态路径和pH触发转变的见解.
- 静电相互作用在观察到的形态过渡和对照的排序中起着重要作用.
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