DPI, P.O. Box 902AX, Eindhoven, 5600, The Netherlands.
Department of Chemical Engineering & Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513 MB Eindhoven, Eindhoven, 5600, The Netherlands.
Macromol Rapid Commun. 2021 Jan;42(1):e2000476. doi: 10.1002/marc.202000476. Epub 2020 Oct 14.
A new mechanophore for polyurethane thermoplastic elastomers based on ion-paired complexes is developed. 8-(2-hydroxyethoxy)pyrene-1,3,6-trisulfonate (HEPTS) is incorporated into polyurethanes as an end-capper and aggregates in apolar media. Aggregation of the ionic HEPTS end groups in solution depends on concentration solvent polarity. The addition of dimethylformamide to a tetrahydrofuran solution of the polymer results in the dissociation of the aggregates and a significant shift in fluorescence emission from yellow to blue. The same shift in fluorescence emission is induced by stretching the solid polymer at strains larger than 1 and stresses above 7.5 MPa, with a clear increase above 12.5 MPa. Strain induced dissociation of HEPTS aggregates not attached to the polymer chain leads to fluorescence changes that are much less reproducible.
开发了一种基于离子对配合物的新型聚氨酯热塑性弹性体机械增感剂。8-(2-羟乙氧基)芘-1,3,6-三磺酸盐 (HEPTS) 作为端基封端剂掺入聚氨酯中，并在非极性介质中聚集。离子型 HEPTS 端基在溶液中的聚集取决于浓度和溶剂极性。向聚合物的四氢呋喃溶液中加入二甲基甲酰胺会导致聚集物的解聚，以及荧光发射从黄色到蓝色的显著位移。在应变大于 1 和应力大于 7.5 MPa 时拉伸固体聚合物也会引起相同的荧光发射位移，在超过 12.5 MPa 时会明显增加。与聚合物链不相连的 HEPTS 聚集物的应变诱导解聚会导致荧光变化，其重现性要差得多。
