Hydrogen-bonded pyridine-based transparent and yellowing-resistant high-strength self-healing polyurethane elastomer

Abstract

The invention discloses a transparent anti-yellowing high-strength self-healing polyurethane elastomer based on hydrogen-bonded pyridine, which is composed of alicyclic diisocyanate, 2,6-pyridinedimethanol (2,6-pyridinedimethanol, PDM), polyether binary Synthesis of amine or polyether diol three types of monomers. Due to the bulky steric hindrance effect of cycloaliphatic diisocyanate, the degree of microphase separation is weakened, and the arrangement of hard segments is loose, which is conducive to the activation energy of reversible hydrogen bonding and realizes room temperature repair. Using polytetramethylene ether with crystallization ability as the soft segment, significant strain-induced crystallization occurs during the stretching process, and the mechanical strength is greatly improved. The invention effectively avoids the competitive dependence of mechanical strength and self-repairing ability on the movement of hard phase segments by regulating the aggregation state and constructing strong and weak hydrogen bonds. Control R value within 2.2~2.6, tensile strength not less than 12MPa, toughness not less than 70MJ / m 3 , The repair time is 24 hours at 25°C, the elongation repair rate is not less than 90%, the treatment is 800 hours at 80°C, and the light transmittance is not less than 90%. The elastomer can be thermoplastically processed, is easy to recycle, and has high application value in the field of flexible electronic equipment.

Description

technical field [0001] The invention relates to the technical field of polymer materials, in particular to a transparent anti-yellowing high-strength self-healing polyurethane elastomer based on hydrogen-bonded pyridine. Background technique [0002] Intrinsic self-healing polyurethane elastomers are important carrier materials for flexible and wearable electronic devices. Flexible electronic devices require carrier materials with ultra-high durability and flexibility, and efficient repairability of functions requires carrier materials to have excellent self-healing capabilities. Therefore, it is very important to balance the mechanical strength and efficient self-healing ability to promote practical applications. The self-healing ability of polyurethane stems from the reversible combination of dynamic covalent bonds and non-covalent bonds in the hard phase, and the mechanical strength strongly depends on the chain segment motion in the hard segment region. The dependence o...

AI Technical Summary

Problems solved by technology

Dynamic covalent bonds can build efficient self-healing capabilities, but cannot avoid problems such as multiple repairs, reduced repair efficiency under long-term high temperature tolerance, and reduced transparency

At present, a large number of researchers have explored highly efficient self-healing elastomers based on dynamic non-covalent bonds, but the mechanical strength is still at a low level.

Images