在水溶液中通过反序聚合诱导的自我组装合成聚烯氧化物) -聚烯 (N,N'-二甲基烯胺) 双块共聚合物纳米粒子
Matthew A H Farmer1, Osama M Musa2, Iris Haug3
1Department of Chemistry, University of Sheffield, Dainton Building, Brook Hill, Sheffield, South Yorkshire S3 7HF, U.K.
Macromolecules
|January 15, 2024
概括
用反序列聚合诱导的自我组装方法合成了固态稳定的双块共聚合物纳米粒子. 这些纳米粒子表现出热反应性行为,形成可逆凝和脱凝的凝.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 立体稳定双块共聚物纳米颗粒为各种应用提供了独特的特性.
- 基于聚乙烯氧化物 (PPO) 的材料由于其可调节性质而引起人们的兴趣.
- 控制的聚合技术对于合成精确定义的纳米结构至关重要.
研究的目的:
- 用于制备带有聚氧化核心的绝缘稳定双块共聚合物纳米颗粒.
- 研究这些纳米粒子在水溶液中的自我组装行为和热反应性质.
- 探索这些纳米颗粒在形成热可逆的微粒凝中的潜力.
主要方法:
- 在水溶液中利用逆序聚合诱导自组合 (PISA).
- 使用的可逆添加碎片链转移 (RAFT) 聚合N,N'-Dimethylacrylamide (DMAC) 的聚合.
- 使用动态光散射和传输电子显微镜来表征纳米粒子大小和形态.
主要成果:
- 在20°C时成功合成了PPO核心纳米粒子,其直径在120-190nm之间.
- 已证明具有高单体转化率 (>99%) 和低分散率 (Mw/Mn ≤ 1.31) 的良好控制的RAFT聚合物.
- 观察到显著的热敏反应性行为,纳米颗粒在70°C时缩小到~33nm,并在15-25%w/w度下形成热可逆的微粒凝.
结论:
- 反向序列PISA是一种有效的方法,用于创建定义精确,固态稳定PPO核心纳米粒子.
- 合成的纳米粒子表现出可调节的热响应性质,从分散过渡到紧的球体,然后到状凝.
- 这些发现突显了这些纳米粒子在需要刺激响应材料的应用中的潜力,例如在水凝形成中.
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