Jun Zhang,Rongye Guo,Yubing Li,Hanyu Ma,Junkun Tang,Zuozhen Liu,Farong Huang
Poly(1,2,3-triazolium) (PTAM) is a kind of self-healing adhesive based on dynamic reversible covalent 1,2,3-triazolium, which is formed through the reaction of halogenated hydrocarbon and 1,2,3-triazole and plays an important role in the properties of PTAM. Therefore, it is valuable to understand the effect of halogenated hydrocarbon crosslinkers on the properties of PTAM. A series of PTAM adhesive with different crosslinkers have been prepared. The reactivity between halogenated hydrocarbon and 1,2,3-triazole was different. Crosslinkers with longer chain, iodine substituted and aromatic structure improved the adhesive property of PTAM adhesive joints, which was up to 17 MPa. The first self-healing efficiency of PTAM adhesive joints with aliphatic bromine crosslinkers reached more than 100% and the maximum cycle times of them was more than 9 before failure. The self-healing properties of PTAMs depend on the segment motion and anti-thermal oxygen aging of PTAMs. These results provide some insights for the structural design of self-healing adhesive and dynamic covalent materials.
Wang Ping,Zhang Di,Zhou Yiyang,Li Yu,Fang Huagao,Wei Haibing,Ding Yunsheng
A novel biodegradable 1,2,3-triazolium-functionalized PEG- b -PCL copolymer (TAPEC) was synthesized by the “click” coupling of methoxypolyethylene glycol azide and α-propargyl-ω-hydroxyl-poly(ε-caprolactone), followed by the quaternization of the 1,2,3-triazole moiety with iodomethane. All the intermediates and TAPEC were characterized by 1 H NMR, FT-IR, and gel permeation chromatography (GPC). Taking advantage of the characteristics of ionic liquid and block copolymer, this ion-containing diblock copolymer is expected to be used as a novel compatibilizer in mixed biopolyester for regulating the interface and crystallization behaviors. Hence, the TAPEC was evaluated as a compatibilizer and an interface emulsifier in the blends of polylactic acid (PLA) and poly(ε-caprolactone) (PCL). Non-isothermal crystallization experimental results showed that the TAPEC with the higher amount of ε-caprolactone units induces a plasticization and nucleate effect that increased the crystallization ability of the PLA phase; meanwhile, in the PCL phase, the agminated ionic cluster acting as a nucleating agent significantly increased the crystalline of PCL.
A new class of inulin derivatives possessing 1,2,3-triazolium charged units by associating “click reaction” with efficient 1,2,3-triazole quaternization were designed and synthesized. After the chemical modification, all the inulin derivatives showed good solubility in water, and exhibited excellent bioactivity compared to inulin. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay, the scavenging activity of 1,2,3-triazolium inulin derivatives (5a–5d) (IC50 0.21–0.29 mg mL−1) was found to be higher than that of inulin derivatives (4a–4d) (IC50 0.58–0.95 mg mL−1) and inulin. 5a–5d (IC50 < 0.01 mg mL−1) also exhibited stronger inhibitory activity against superoxide anion formation than 4a–4d (IC50 0.02–0.09 m g mL−1) and Vitamin C (IC50 0.02 mg mL−1). In the antifungal assays, 5a–5d also inhibited the growth of tested phytopathogens more effectively with inhibitory indices of 43.10–82.56% at 1.0 mg mL−1, compared with 4a–4d and inulin. Based on these data, it is reasonable to propose that the introduction of 1,2,3-triazolium group through chemical modification is significant to enhance the free radical-scavenging activity and antifungal activity of inulin.