Microphase separation in polymeric systems provides a bottom-up strategy to fabricate nanostructures. Polymers that are reported to undergo microphase separation usually include block copolymers or polyelectrolytes. Neutral homopolymers, which are comparatively easy to synthesize, are thought to be incapable of microphase separation. Here, using a minimal model that accounts for ion solvation, we show that microphase separation is possible in neutral homopolymer blends with sufficient dielectric contrast, upon a tiny amount of salt-doping. The driving force for the microphase separation is the competition between selective ion solvation, which places smaller ions in domains with higher dielectric constant, and the propensity for local charge neutrality to decrease the electrostatic energy. The compromise is an emergent length over which microphase separation occurs and ions are selectively solvated. The factors affecting such competitions are explored, including ion solvation radii, dielectric contrast, and polymer fraction, which point to directions for observing this behavior experimentally. These findings suggest a low-cost and facile alternative to produce microphase separation which may be exploited in advanced material design and preparation.

中文翻译：

---

盐掺杂诱导的中性均聚物共混物中的微相分离

聚合物系统中的微相分离为制造纳米结构提供了一种自下而上的策略。据报道经历微相分离的聚合物通常包括嵌段共聚物或聚电解质。比较容易合成的中性均聚物被认为不能进行微相分离。在这里，使用考虑离子溶剂化的最小模型，我们表明在少量盐掺杂的情况下，在具有足够介电对比度的中性均聚物混合物中，微相分离是可能的。微相分离的驱动力是选择性离子溶剂化（将较小的离子置于具有较高介电常数的域中）与局部电荷中性倾向以降低静电能之间的竞争。折衷方案是出现微相分离和离子被选择性溶剂化的出现长度。探讨了影响此类竞争的因素，包括离子溶剂化半径、介电对比度和聚合物分数，这为通过实验观察这种行为指明了方向。这些发现表明了一种产生微相分离的低成本和简便的替代方案，可用于先进的材料设计和制备。