Monodisperse and Telechelic Polyethylenes Form Extended Chain Crystals with Ionic Layers
Monodisperse and Telechelic Polyethylenes Form Extended Chain Crystals with Ionic Layers
复制标题
单分散和遥爪聚乙烯形成具有离子层的长链晶体
DOI：
10.1021/acs.macromol.9b00962
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发表时间：
2019
期刊：
影响因子：
5.5
通讯作者：
K. Winey
中科院分区：
文献类型：
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作者：
Lu Yan;M. Häußler;J. Bauer;S. Mecking;K. Winey
我们报道了合成具有精确链长的离子远螺旋低分子量聚乙烯（PEs），该聚乙烯来源于植物油，具有其形态和温度依赖的离子电导率。以C48远旋二甲酯或C23类似物为对照，采用微波辅助皂化化学方法引入了不同的羧酸离子端基（H+、Na+、Cs+、Zn2+）。由于聚乙烯序列的精确长度，这些双官能远螺旋聚乙烯在室温下结晶成非常有序的纳米级层状结构。由于其延伸链晶体性质，层厚度直接由远旋分子亚甲基链长度编码。差示扫描量热法和原位x射线散射结果表明，C21(COONa)2、C46(COONa)2和C46(COOCs)2的晶体结构在完全无序熔体状态之前发生了转变。熔化转变是…
We report the synthesis of ionic telechelic low-molecular-weight polyethylenes (PEs) with precise chain lengths that are derived from plant oils along with their morphologies and temperature-dependent ionic conductivities. Starting from the C48 telechelic dimethyl ester, or the C23 analogue for comparison, different ionic carboxylate end groups (H+, Na+, Cs+, Zn2+) were introduced by microwave-assisted saponification chemistry. Because of the precise length of the polymethylene sequence, these difunctional telechelic PEs crystallize into exceptionally well-ordered nanoscale-layered structures at room temperature. As a consequence of their extended chain crystal nature, the layer thickness is directly encoded by the telechelic molecules methylene chain length. Notably, C21(COONa)2, C46(COONa)2, and C46(COOCs)2 exhibit transitions in the crystalline structure prior to the fully disordered melt state, as evidenced by differential scanning calorimetry and in situ X-ray scattering. The melting transition is ty...