A Stretchable Pillararene-Containing Supramolecular Polymeric Material with Self-Healing Property

Constructing polymeric materials with stretchable and self-healing properties arise increasing interest in the field of tissue engineering, wearable electronics and soft actuators. Herein, a new type of supramolecular cross-linker was constructed through host-guest interaction between pillar[5]arene functionalized acrylate and pyridinium functionalized acrylate, which could form supramolecular polymeric material via photo-polymerization of n-butyl acrylate (BA). Such material exhibited excellent tensile properties, with maximum tensile strength of 3.4 MPa and strain of 3000%, respectively. Moreover, this material can effectively dissipate energy with the energy absorption efficiency of 93%, which could be applied in the field of energy absorbing materials. In addition, the material showed self-healing property after cut and responded to competitive guest.


Synthesis of compound 3
1,6-dibromohexane (10.6g, 43mmol), K2CO3 (18.4g,133mmol) and KI (3.32g,20mmol) were dissolved in CH3CN (100ml). After complete dissolution, acrylic acid (2.4g, 33mmol) was added drop by drop. The reaction took place at 80℃ under the protection of N2 atmosphere for three days. After the reaction, the filtrate was cleaned and filtered by dichloromethane for several times. The filtrate was combined and concentrated. The crude product was further purified by silica gel column chromatography (eluent: petroleum ether/dichloromethane = 100:1, v/v). The yellow viscous liquid of 4.6g (yield 46%). The 1 H NMR spectrum of compound 3 is shown in

Synthesis of pyridinium functionalized acrylate (G)
The compound 3 (1.0 g, 4 mmol) and pyridine (30 ml) were stirred at room temperature for three days, and the excess pyridine was removed by vacuum distillation. The resulting liquid was precipitated in ether to obtain a brown liquid of 0.92g (yield: 98%).

NMR titration study of the complexation between AAP5A and G
The formation of supramolecular cross-linking molecule was studied by using AAP5A and G as templates. The complexation process was further studied by changing (f) Add 0.5 mL solution of G (4 mM) to sample (g) and take out 0.5 mL.
(e) Add 0.5 mL solution of G (4 mM) to sample (f) and take out 0.5 mL.
(d) Add 1.06 mL solution of G (4 mM) to sample (e) and take out 0.5 mL.
(c) Add 0.30 mL solution of G (4 mM) to sample (d) and take out 0.5 mL.
(b) Add 0.75 mL solution of G (4 mM) to sample (c) and take out 0.5 mL.   Table S1. Feeding ratio of Covalent bond and supramolecular polymeric material.   Figure S15. The full (upper) and partial enlarged (bottom) FT-IR spectra of AAP5A (a); G (b);