The formation of complex structures in thin films is of interest in many fields. Segregation of polymer chains of different molecular weights is a well-known process. However, here, polystyrene with bimodal molecular weight distribution, but no additional chemical modification was used. It was proven that at certain conditions, the phase separation occurred between two fractions of bimodal polystyrene/methyl ethyl ketone solution. The films were prepared by spin-coating, and the segregation between polystyrene phases was investigated by force spectroscopy. Next, water vapour induced secondary phase separation was investigated. The introduction of moist airflow induced the self-assembly of the lower molecular weight into islands and the heavier fraction into a honeycomb. As a result, an easy, fast, and effective method of obtaining island/honeycomb morphologies was demonstrated. The possible mechanisms of the formation of such structures were discussed.

薄膜中复杂结构的形成在许多领域都受到关注。不同分子量的聚合物链的分离是众所周知的过程。然而，在这里，聚苯乙烯具有双峰分子量分布，但没有使用额外的化学改性。证明在一定条件下，双峰聚苯乙烯/甲乙酮溶液的两部分之间发生相分离。通过旋涂制备薄膜，并通过力谱研究聚苯乙烯相之间的分离。接下来，研究了水蒸气诱导的二次相分离。潮湿气流的引入导致较低分子量的自组装成岛，而较重的部分自组装成蜂窝。因此，一个简单、快速、并证明了获得岛/蜂窝形态的有效方法。讨论了形成这种结构的可能机制。