反阳离子类型影响多电解质复合物的玻璃过渡温度
Suvesh Manoj Lalwani1, Kayla Hellikson1, Piotr Batys2
1Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, United States.
Macromolecules
|June 3, 2024
概括
盐离子的类型影响了多电解质复合物 (PEC) 的玻璃过渡温度 (Tg). 增加了离子离子.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 物理化学 物理化学
背景情况:
- 盐在多电解质复合物 (PEC) 中起着塑化剂的作用,影响其物理,热和机械性能.
- 添加的盐破坏了水合PEC中的内在离子对,降低了它们的玻璃过渡温度 (Tg).
- 反类型对PEC Tg的特定影响尚不清楚.
研究的目的:
- 为了研究不同类型的盐离子对水合聚二甲基 (PDADMA) -多二硫酸盐 (PSS) PECs的Tg的影响.
- 要了解阴离子的混沌性质如何影响PEC Tg.
- 探索PEC中离子对,水含量和Tg之间的关系.
主要方法:
- 研究了含有不同盐离子类型 (NaCl,NaBr,NaNO3,NaI) 的化PDADMA-PSS PECs的Tg.
- 分析了增加阴离子的混变性质对Tg的影响.
- 检查了Tg,内在离子对和含水量之间的缩放关系.
主要成果:
- 水合PEC的Tg随着盐离子的混乱性质的增加而降低.
- 阴离子类型影响了Tg,原因是兴奋剂水平,结合水,水流动性和聚合物相互作用.
- 在所有盐类型和度中,Tg遵循了-1 / Tg ≈ ln (([IP]/[H2O]) 的缩放.
结论:
- 固态类,化PEC的Tg受到盐离子类型的显著影响.
- 在这些PEC中,玻璃化过渡的基本机制无论盐类型如何,都保持一致.
- 该研究提供了对PEC中玻璃化过渡所需的离子对破坏的定量估计.
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