文献类型：期刊文献

英文题名：Crystallization-Driven Self-Assembly of Oligo(p-phenylenevinylene) Derivatives toward π-Conjugated Nanostructures: The Effect of Chain Length and Chain End Groups

作者：Wang, Zhongming[1];Xia, Longgang[1];Huang, Guanwen[1];Du, Xinghao[1];Xu, Binbin[1];Feng, Chun[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai Key Lab Adv Polymer Mat, Shanghai 200237, Peoples R China

年份：2025

卷号：41

期号：27

起止页码：18292

外文期刊名：LANGMUIR

收录：;EI(收录号：20252718715470);WOS:【SCI-EXPANDED(收录号:WOS:001523145800001)】；

基金：The authors are thankful for financial support from the National Natural Science Foundation of China (U22A20131, 52361165657, 52473005, and 52273008) and the Shanghai Rising-Star Program (23QA1402500). The authors thank Dr. Kun Cui for his assistance in TEM measurements and the beamline BL16B1 at SSRF for providing the beam time.

语种：英文

外文关键词：Chains - Charge transfer - Fluorescence - Micelles - Micrometers - Nanostructures - Self assembly

摘要：Crystallization-driven self-assembly (CDSA) of pi-conjugated homopolymers/oligomers has emerged as a versatile strategy to generate various nanostructures without an extra polymer corona layer. However, this field remains in its infancy, with rare reports concerning this topic. To get an in-depth understanding of how the structure of pi-conjugated homopolymers/oligomers affects CDSA behavior, in this contribution, a series of oligo(p-phenylenevinylene) derivatives (OPV n , where the subscript represents the number of repeat units) with different chain lengths (n = 3, 4, or 5) and chain end groups of aldehyde (CHO) and cyano/carboxyl (CN/COOH) were synthesized. The influence of the chain length and structure of the chain end groups of OPV on CDSA behavior was examined in detail. It was found that the increase in the chain length of OPV would increase the stacking strength of OPV units for both CHO- and CN/COOH-terminated OPV. In addition, the introduction of more electron-deficient CN/COOH units would lead to a more pronounced electron pull-push effect, which not only resulted in the red shift of the UV/vis absorbance and fluorescence bands of OPV but also increased the stacking strength of OPV units as a consequence of the enhancement of charge transfer interactions. CHO-terminated OPV3-CHO and OPV4-CHO and CN/COOH-terminated OPV3-COOH remained in unimolecularly dissolved states in n-butanol at 25 degrees C. On the contrary, OPV5-CHO formed ribbon-like micelles with widths in the range from similar to 20 to similar to 150 nm and lengths up to several micrometers, and OPV4-COOH formed ribbon-like micelles with a width of similar to 20 nm under the same conditions. Interestingly, tube-like micelles with a length of tens of micrometers could be formed for OPV5-COOH. By virtue of acid-base interactions, amino-based porphyrins can be immobilized onto the surface of the micelles of OPV5-COOH. This work demonstrates a vital role of the chemical structure of pi-conjugated oligomers/polymers in determining CDSA behavior, which will be beneficial to extending CDSA toward the creation of various functional pi-conjugated nanostructures.