Poly(ethylene-b-styrene-b-ethylene) (ESE) triblock copolymer-based alkaline anion-exchange membranes (AAEMs) were synthesized and characterized to evaluate the effects of polydispersity and ion exchange capacity (IEC) on the structures and properties of semicrystalline block copolymer AAEMs. The ESE AAEMs with relatively low polydispersity (Đ < 1.9) formed long-range-ordered lamellar microstructures oriented primarily parallel to the membrane surface, which resulted in adversely rough membrane surfaces and low strain at break (<60%). In contrast, the ESE AAEM with a relatively high polydispersity (Đ ≈ 2.5) developed microphase-separated domains without long-range order and formed membranes with smooth surfaces and excellent strain at break (>350%). These polydispersity-driven changes to the long-range-ordered states of block copolymer membranes show that the microphase separation in block copolymers benefits the dimensional stability and conductivity, but the long-range ordering of microphase-separated domains in block copolymers is not necessarily beneficial for the overall properties of block copolymer-based membranes.

中文翻译：

---

使用半结晶三嵌段共聚物在有序和无序状态下阴离子交换膜的合成和表征

合成了基于三嵌段共聚物的聚（乙烯-b-苯乙烯-b-乙烯）（ESE）碱性阴离子交换膜（AAEMs），并进行了表征，以评估多分散性和离子交换容量（IEC）对结构和性能的影响。半结晶嵌段共聚物AAEM。具有相对低的多分散性的ESE AAEMs（Đ <1.9）形成主要平行于膜表面取向长程有序层状微观结构，这导致断裂（<60％）不利地粗糙膜表面和低应变。与此相反，ESE AAEM具有相对高的多分散性（Đ≈2.5）形成了没有长程有序的微相分离域，并形成了具有光滑表面和出色的断裂应变（> 350％）的膜。这些多分散性驱动的嵌段共聚物膜长程状态变化表明，嵌段共聚物中的微相分离有利于尺寸稳定性和电导率，但嵌段共聚物中微相分离域的长程排序不一定有利嵌段共聚物膜的整体性能。