Shuzhen Zheng,Wenxiu Qiao,Jianfeng Ma,Yinwen Li,Shoufang Xu,Qianping Ran
Using organic/inorganic nanocomposites to optimize the microstructures of cement hydration products at the micro/nanometre scale is a promising method for improving the mechanical properties of cement-based materials. One type of novel nanohybrid material modified by the flexible autonomous healing polymer poly-TA (thioctic acid) was synthesized and used as a highly efficient mechanical improvement agent for cement paste. The nanohybrids linear LNTS-1 and bulk CNTS-2 were synthesized from silane-coupled nanosilica and alpha thioctic acid. Due to the existence of hydrogen bonds, coordination bonds and dynamic covalent S S bonds, this type of linear poly-TA with a certain amount of calcium content exhibited good self-healing properties. Linear LNTS-1 can effectively improve the macro flexural strength of cement-based materials without a negative effect on their compressive strength. The flexural strength of cement pastes with 1.0‰ LNTS-1 increased by 11.9%, 15.6%, and 16.9% after curing for 3, 7, and 28 d compared with the control cement paste. The results of adsorption experiments show that nanohybrid LNTS-1 has strong adsorption on calcium ions, which affects the formation of cement hydration products.
For a long time, the potential application of gel-based ionic devices was limited by the problem of liquid leakage or evaporation. Here, we utilized amorphous, irreversible and reversible cross-linked polyTA (PTA) as a matrix and lithium bis(trifluoromethane sulfonamide) (LiTFSI) as an electrolyte to prepare a stretchable (495%) and self-healing (94%) solvent-free elastomeric ionic conductor. The liquid-free ionic elastomer can be used as a stable strain sensor to monitor human activities sensitively under extreme temperatures. Moreover, the prepared elastic conductor (TEOA0.10-PTA@LiTFSI) was also considered an electrode to assemble with self-designed repairable dielectric organosilicon layers (RD-PDMS) to develop a sustainable triboelectric nanogenerator (SU-TENG) with outstanding performance. SU-TENG maintained good working ability under extreme conditions (−20 °C, 60 °C, and 200% strain). This work provided a low-cost and simple idea for the development of reliable iontronic equipment for human–computer interaction, motion sensing, and sustainable energy.
Self-healing, self-adhesive, and stretchable bio-based conductive hydrogels exhibit properties similar to those of biological tissues, making them an urgent requirement for emerging wearable devices. The primary challenge lies in devising straightforward strategies to accomplish all the aforementioned performances and achieve equilibrium among them. This study used the natural compound thioctic acid (TA) and modified cellulose to prepare conductive hydrogels with stretchability, healing, and self-adhesion through a simple one-step strategy. Metastable poly(TA) was obtained through ring-opening polymerization of lithiated TA, followed by the introduction of dopamine-grafted cellulose nanofibers (DCNF) to stabilize poly(TA) and prepare PTALi/DCNF hydrogels with the aforementioned properties. The hydrogels demonstrated remarkable conductivity, attributed to the existence of Li + ions, with a maximum conductivity of 17.36 mS/cm. The self-healing capacity of the hydrogels was achieved owing to the presence of disulfide bond in TA. The introduction of DCNF can effectively stabilize poly(TA), endow the hydrogel with self-adhesion ability, improve the mechanical properties, and further enhance the formability of hydrogels. Generally, bio-based PTALi/DCNF hydrogels with stretchability, self-healing, self-adhesion, and conductivity are obtained through a simple strategy and used as a sensor with a wide response range and high sensitivity. Hydrogels have significant potential for application in wearable electronic devices, electronic skins, and soft robots.
危险品化学品经营许可证（带存储）