当前位置：
X-MOL 学术
›
Macromolecules
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Influence of Nonstoichiometry on the Viscoelastic Properties of a Polyelectrolyte Complex
Macromolecules ( IF 5.1 ) Pub Date : 2021-09-02 , DOI: 10.1021/acs.macromol.1c01154 Yuhui Chen 1 , Mo Yang 1 , Samir Abou Shaheen 1 , Joseph B. Schlenoff 1
Macromolecules ( IF 5.1 ) Pub Date : 2021-09-02 , DOI: 10.1021/acs.macromol.1c01154 Yuhui Chen 1 , Mo Yang 1 , Samir Abou Shaheen 1 , Joseph B. Schlenoff 1
Affiliation
|
Depending on conditions such as the mixing ratio, speed and order of addition, and ionic strength, when solutions of oppositely charged polyelectrolytes are mixed, the stoichiometry of the formed polyelectrolyte complexes (PECs) can vary. In fact, for most conditions, some degree of nonstoichiometry is inevitable because the ratios of positive and negative charges do not “lock” themselves to 1:1, as was believed in some early work. PEC morphologies and mechanical properties depend on the molar ratio between the polycation and polyanion. In this work, poly(diallyldimethylammonium) and poly(styrene sulfonate) were used to make PECs with varying stoichiometries. PECs that were overcompensated with one polyelectrolyte were shown to have lower glass transition temperatures and moduli due to the plasticizing effect caused by increased water content. In addition, time–temperature superposition revealed a correlation between segmental relaxation times and stoichiometry. Nonstoichiometric PECs were shown to have elevated fractional free volumes and decreased polymer volume fractions, which are responsible for changes in their mechanical properties.
中文翻译：
非化学计量对聚电解质复合物粘弹性的影响
根据混合比、添加速度和顺序以及离子强度等条件，当混合带相反电荷的聚电解质溶液时，形成的聚电解质复合物 (PEC) 的化学计量会发生变化。事实上，在大多数情况下，一定程度的非化学计量是不可避免的，因为正负电荷的比率不会像一些早期工作中认为的那样“锁定”到 1:1。PEC 形态和机械性能取决于聚阳离子和聚阴离子之间的摩尔比。在这项工作中，聚（二烯丙基二甲基铵）和聚（苯乙烯磺酸盐）用于制造具有不同化学计量的 PEC。由于含水量增加引起的增塑效应，用一种聚电解质过度补偿的 PEC 显示出较低的玻璃化转变温度和模量。此外，时间-温度叠加揭示了节段弛豫时间和化学计量之间的相关性。非化学计量 PEC 的自由体积分数升高，聚合物体积分数降低，这是导致其机械性能变化的原因。
更新日期：2021-09-14
中文翻译：
非化学计量对聚电解质复合物粘弹性的影响
根据混合比、添加速度和顺序以及离子强度等条件，当混合带相反电荷的聚电解质溶液时，形成的聚电解质复合物 (PEC) 的化学计量会发生变化。事实上，在大多数情况下，一定程度的非化学计量是不可避免的，因为正负电荷的比率不会像一些早期工作中认为的那样“锁定”到 1:1。PEC 形态和机械性能取决于聚阳离子和聚阴离子之间的摩尔比。在这项工作中，聚（二烯丙基二甲基铵）和聚（苯乙烯磺酸盐）用于制造具有不同化学计量的 PEC。由于含水量增加引起的增塑效应，用一种聚电解质过度补偿的 PEC 显示出较低的玻璃化转变温度和模量。此外，时间-温度叠加揭示了节段弛豫时间和化学计量之间的相关性。非化学计量 PEC 的自由体积分数升高，聚合物体积分数降低，这是导致其机械性能变化的原因。
京公网安备 11010802027423号