Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA.
Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.
Angew Chem Int Ed Engl. 2023 Jun 5;62(23):e202302739. doi: 10.1002/anie.202302739. Epub 2023 May 2.
Experimental results are presented that serve to lower the barrier for developing the science and technology of non-classical thermotropic glycolipid mesophases, which now include dodecagonal quasicrystal (DDQC) and Frank-Kasper (FK) A15 and σ mesophases that can be produced under mild conditions from a versatile class of sugar-polyolefin conjugates. By employing "alloys" comprised of mono- and disaccharide-polyolefin conjugates, and optionally with vitamin E as a small molecule phase modulator, we report the spontaneous formation of stable A15 mesophases at ambient temperature. We further document a rich thermotropic phase map that includes DDQC, A15, and σ mesophases of tunable periodicity that are connected through rapid thermotropic phase transitions as a function of increasing temperature in the order: liquid-like packing (LLP)→DDQC → A15→σ→ disorder. This first direct observation of a rapid thermotropic A15→σ phase transition provides support for a diffusionless martensitic process proceeding through strain-induced introduction of planar defects into the A15 lattice.
实验结果表明，开发非经典热致糖脂中间相科学技术的障碍有所降低，这些中间相现在包括十二面体准晶（DDQC）和 Frank-Kasper（FK）A15 和 σ 中间相，可以在温和条件下从各种糖-聚烯烃缀合物中产生。通过使用由单糖和二糖-聚烯烃缀合物组成的“合金”，并可选地使用维生素 E 作为小分子相调节剂，我们报告了在环境温度下稳定 A15 中间相的自发形成。我们进一步记录了丰富的热致相图，其中包括 DDQC、A15 和 σ 中间相，其周期性可调，通过在升高温度的过程中快速热致相转变连接在一起，顺序为：类似液体的堆积（LLP）→DDQC→A15→σ→无序。这种对快速热致 A15→σ 相转变的首次直接观察为通过应变诱导向 A15 晶格中引入平面缺陷来进行无扩散马氏体过程提供了支持。
