Solid-state stimuli-responsive materials are attracting increasing attention due to their broad prospects in the field of functional materials, but there are still some challenges. We design and synthesize two efficient solid-state stimuli-responsive materials SP-TPEm ( m = 4, 6) based on TPE covalent connection with N -position of spiropyran through different lengths of alkyl spacers. Both of them show aggregation-induced emission behaviors. Efficient solid-state photoswitching between SP-TPEm and their photoisomer MC-TPEm is achieved. Both of the two films show great stimulus-responsive properties, and the characteristic emission peak is at around 460 nm for TPE and 601 nm for MC isomer. Therefore, SP-TPE4 is applied as an anticounterfeiting ink due to its great solid-state photochromic characteristics. In addition, the solid-state films of SP-TPEm are acidochromic responsive. Moreover, the surface wettability of the SP-TPEm films can be adjusted by UV light. Hence, we provide a new strategy for building solid-state multifunctional materials.

中文翻译：

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四苯基乙烯和螺吡喃构建的固态光致变色和酸致变色多功能材料

固态刺激响应材料因其在功能材料领域的广阔前景而受到越来越多的关注，但仍存在一些挑战。我们设计并合成了两种高效的固态刺激响应材料 SP-TPEm ( m = 4, 6)，其基于 TPE 通过不同长度的烷基间隔与螺吡喃的 N 位共价连接。它们都表现出聚集诱导的发射行为。实现了 SP-TPEm 与其光异构体 MC-TPEm 之间的高效固态光开关。两种薄膜都显示出很好的刺激响应特性，TPE 的特征发射峰在 460 nm 左右，MC 异构体​​的发射峰在 601 nm 左右。因此，SP-TPE4 由于其出色的固态光致变色特性而被用作防伪油墨。此外，SP-TPEm 的固态薄膜具有酸致变色响应性。此外，SP-TPEm 薄膜的表面润湿性可以通过紫外线进行调节。因此，我们提供了一种构建固态多功能材料的新策略。