Morphological Impact of Segment Dispersity in Lithium Salt-Doped Poly(styrene)/Poly(ethylene oxide) Triblock Polymers
Morphological Impact of Segment Dispersity in Lithium Salt-Doped Poly(styrene)/Poly(ethylene oxide) Triblock Polymers
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DOI：
10.1021/acs.macromol.9b00900
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发表时间：
2019-07
期刊：
影响因子：
5.5
通讯作者：
Hongyun Xu;Eric Greve;M. Mahanthappa
中科院分区：
文献类型：
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作者：
Hongyun Xu;Eric Greve;M. Mahanthappa
研究了中心链段分散度对17种锂盐掺杂聚(苯乙烯-低聚环氧乙烷)碳酸酯-苯乙烯三嵌段聚合物相行为的影响，其中宽分散度O嵌段(ĐO=mW/mN≈1.45)位于窄分散度S链段(ĐS≤1.18)之间，体积分数fo=0.33~0.69，总Mn=11.6~43.8 kg/mol。通过串联缩聚和原子转移自由基聚合反应合成了宽分散性bSOS三嵌段。利用随温度变化的小角X射线散射，绘制了双(三氟甲基磺酰亚胺)锂(LiTFSI)掺杂的bSOS样品的形貌图，其中r=(摩尔Li+)/(摩尔环氧乙烷)=0.00-0.09。与13个掺杂LiTFSI的窄分散度SOS三元组(fo=0.30~0.58，Mn=7.1~45.2 kg/mol)的相行为比较表明，O段分散度使片层形态窗口向较高fO/盐方向移动，片层微区尺寸减小。
We investigate the impact of center segment dispersity on the phase behavior of 17 lithium salt-doped poly(styrene-block-oligo(ethylene oxide) carbonate-block-styrene) (bSOS) triblock polymers, in which broad dispersity O blocks (ĐO = Mw/Mn ≈ 1.45) are situated between narrow dispersity S segments (ĐS ≤ 1.18) with volume fractions fO = 0.33–0.69 and total Mn = 11.6–43.8 kg/mol. Broad dispersity bSOS triblocks are synthesized by a tandem polycondensation and atom transfer radical polymerization reaction sequence. Using temperature-dependent small-angle X-ray scattering, we map the morphology diagrams for bSOS samples variously doped with lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) with r = (mol Li+)/(mol ethylene oxide) = 0.00–0.09. As compared to the phase behavior exhibited by 13 LiTFSI-doped, narrow dispersity SOS triblocks with fO = 0.30–0.58 and Mn = 7.1–45.2 kg/mol, we demonstrate that O segment dispersity shifts the lamellar morphology window to higher fO/salt and the lamellar microdomains di...