In this work, a monomer with double bond was introduced to the surface of clay nanosheets via inclusion complexation between cyclodextrin (CD) host and azobenzene (Azo) guest, as well as electrostatic interaction between clay nanoplatelets and cations of azobenzene derivatives. The obtained supra-structure acts as a supramolecular cross-linker in its copolymerization with macromonomer PEG resulting in a hybrid supramolecular hydrogel. Only viscous liquid was obtained in the absence of clay nanoplatelets, revealing the supramolecular cross-linker played an important role in the hydrogel formation. Such hybrid supramolecular hydrogel exhibited good stability and shear thinning property.A hybrid hydrogel was constructed based on the “supramolecular cross-linker” (SCL), which was formed through electrostatic interaction as well as the host–guest complexation between cyclodextrin and azobenzene derivatives. Such hybrid hydrogel exhibited good stability and shear thinning properties.

A multiresponsive supramolecular gel was constructed based on a bis(pyridinium) dication guest and a copolymer with pillararenes as the pendant groups, which was synthesized by free radical copolymerization of methacrylate-functionalized pillararenes and methyl methacrylate. The mechanism of gel formation was explored by the intensive study. Upon addition of competitive host or guest molecules, pillararene-based gel could be transferred into sol due to the competition of host–guest complexation. Surprisingly, the ordered stacking of pillararenes was indispensable to obtain the supramolecular gel, which endowed the system with response to temperature change.

Block copolymers poly(endo-N-3,5-bis(trifluoromethyl)biphenyl-norbornene-pyrrolidine)-block-poly(exo-N-(cinnamoyloxyethyl)-7-oxanorborn-5-ene-2,3-dicarboximide) (endo-PTNP-b-exo-PCONBI) and poly(exo-N-3,5-bis(trifluoromethyl)biphenyl-norbornene-pyrrolidine)-block-poly(exo-N-(cinnamoyloxyethyl)-7-oxanorborn-5-ene-2,3-dicarboximide) (exo-PTNP-b-exo-PCONBI) were synthesized by ring-opening metathesis polymerization. The endo- or exo-PTNP served as the high dielectric functional chain, and exo-PCONBI acted as the crosslinking segment. The endo-PTNP-b-exo-PCONBI, in which endo-PTNP has a high content of trans double bond and adopts isotactic configuration, shows a dielectric constant (ε) of 15.5, whereas exo-PTNP-b-exo-PCONBI, in which exo-PTNP has 67% trans double bonds and atactic microstructure, displays relatively low ε of 7.1. The cinnamate groups in exo-PCONBI were crosslinked to form three-dimensional network by cycloaddition reaction under UV irradiation. Exposed to UV-light for 10 min, the cinnamate group in polymer films has a crosslinking conversion of 36%, as determined by UV-Vis absorption measurements. By photocrosslinking, the polymer film has an increased ε of 16.6, a dielectric loss of 0.03, an elevated glass-transition temperature of 137 °C, and an enhanced decomposition temperature of 405 °C, compared to those of polymer films without irradiation.

•The sensing platform for DNA was constructed based on host–guest interaction between novel pillararenes and alkylamino modified DNA.•The sensing platform could be recycled after simple washing with hot acetonitrile.•The sensing platform exhibited wide linear range and excellent specificity.•Homogeneous DNA hybridization was utilized taking the advantage of free of previous immobilization of DNA probe.In this work, a recyclable electrochemical sensing platform to detect breast cancer susceptibility gene (BRCA) was constructed by pillararenes based host–guest recognition and homogeneous DNA hybridization. BRCA target DNA (T-DNA) formed sandwich-type DNA via homogeneous hybridization with methylene blue labeled signal DNA and alkylamino modified capture DNA, which could form complexes with pillararenes. Such sandwich-type DNA was captured by a novel trithiocarbonate modified pillar[5]arene (P5A-CTA) which was immobilized on the Au electrode. With the help of enzyme amplification, the electrochemical detection signal of target DNA in sensing platform was apparently amplified. This sensing platform exhibited wide linear range and excellent specificity, and was particularly recyclable after simple washing with hot acetonitrile due to the reversible host–guest complexation between P5A-CTA and alkylamino modified DNA.

In this work, we synthesized n-octylpyrazinium bromide(G-Br) and n-octylpyrazinium hexafluorophosphate(G-PF6) as model guests and studied their host-guest complexation with 1,4-dimethoxypillar[5]arene(DMP5A). Effect of alkylpyrazinium counterions on the host-guest recognition was investigated. Based on the 1H NOESY spectra, the binding site of DMP5A with G-PF6 is the same as that of DMP5A with G-Br. However, G-PF6 forms a stronger complex with DMP5A than G-Br, owing to that hexafluorophosphate forms weaker doubly inonic H-bonds with ammonium cation than bromide ion in chloroform, which leads to some aggregates that could be dissociated with the addition of DMP5A.

Oligo(ethylene glycol)-terminated hyperbranched poly(triazole) (hb-PTA-OEG) with thermal and metal ion dual stimuli-responsiveness was synthesized by Cu(I)-catalyzed azide–alkyne cycloaddition polymerization, which possessed a high molecular weight (Mn = 203 kDa) and good thermal properties (Td = 367 °C, Tg = −14.1 °C). Importantly, hb-PTA-OEG exhibited a relatively low cloud point (CP) temperature ranging from 34.4 to 31.1 °C as the concentration was increased from 0.02 to 2.0 wt%. Simultaneously, hb-PTA-OEG has the ability to coordinate with various metal ions, and the type of metal ions influenced the CP of hb-PTA-OEG solution to some extent as a result of their different association strengths with the polymer, particularly, Ag+ ion showed a conspicuous contribution to increasing the CP among the several selected ions. As a result, hb-PTA-OEG can act as an absorber of metal ions, and the selective absorption of Ag+ ion could be reached by tuning temperature.

Acyclic diene metathesis polymerization of a structurally symmetrical perylene bisimide (PBI)-containing α,ω-diene has been performed, yielding an unsaturated polymer with increased molecular weight (Mn = 21.2–87.6 kDa) and decreased polydispersity index (PDI = 2.31–1.76) as the reaction time was prolonged. The subsequent hydrogenation of the as-synthesized polymer was readily accomplished, affording the desired polyethylene (PE) with a saturated backbone and precisely repeating substituted bulky PBI branches. This PBI-substituted PE derivative displayed high glass transition temperatures (Tg = 51.8–75.8 °C), a relatively wide range of light absorption (λ = 230–590 nm), and a highly ordered architecture, which should facilitate electron mobility and be suitable for utilization in optoelectronic devices. It can therefore serve as a superior model for simple construction of functional PE polymers with precisely repeating bulky branches and a soluble PBI polymer with an ordered architecture.

Metathesis cyclopolymerization of 1,6-heptadiyne derivatives is readily utilized to synthesize triphenylamine-functionalized polyacetylenes (TPA-PAs) by a third-generation Grubbs catalyst, which selectively generated TPA-PAs with a five-membered ring and all-trans microstructure. The TPA pendants endowed PAs with good solubility and excellent optoelectronic properties (maximum absorption wavelength of 592–605 nm in CHCl3, HOMO level of around −5.04 eV, and energy bandgap of 1.82–1.77 eV). When bis-TPA side group was introduced into the PA backbone, the resultant polymer, poly(M2), displayed desirable oxidative stability (up to 30 days stored in THF) and high fluorescence quantum yield (up to 12.3%) in the family of PA derivatives. In addition, poly(M2) could spontaneously self-assemble into the nanocylinder architecture without requiring any tedious postsynthetic treatments. This is the first report that the rigid and immobile conjugated PA segment assembled into the novel cylindrical nanostructure with the aid of π–π interaction of TPA side group.