Hu, Jin published the artcileRobust, transparent, and self-healable polyurethane elastomer via dynamic crosslinking of phenol-carbamate bonds, Safety of Propyl 3,4,5-trihydroxybenzoate, the publication is Polymer (2021), 123674, database is CAplus.
Intrinsic self-healing materials designed through the incorporation of noncovalent interactions or dynamic covalent bonds are prized for their ability to recover from mech. damages. However, they often suffer from deteriorated mech. property due to the increased chain mobility. In this work, we reported a high-strength, colorless transparent self-healing polyurethane elastomer through dynamic crosslinking of reversible phenol-carbamate bonds. Tetrabromobisphenol A (TBBPA) and Pr gallate (PG) were used as the dynamic chain extender and dynamic crosslinking agent, resp. They both can be effectively deblocked at mild temperatures ensuring that the self-healing efficiency is not affected by the material formulation. The mech. properties can be tailored in a wide range by varying the crosslink d. and hard segment content, and their combination uniquely determines the material formulation. The phenol-carbamate based polyurethane (PPU) with a hard segment of 60% and a crosslink d. ν of 0.5 mmol cm-3 exhibited a tensile strength up to 46.4 MPa at the break strain of 615% and displayed high elastic resilience. In the meantime, it could be fully healed (ησ = 93%) with 2 h of heating at 100°C after completely cut off. After recycled three times, it still maintained 80% of its original tensile strength. The structural rigidity of the crosslinker PG and the highly reversible phenol-carbamate bond play a crucial role in strengthening the mech. strength while maintaining the self-healing efficiencies at elevated temperatures This work provides a feasible strategy to prepare mech. robust crosslinked polyurethane elastomer with high self-healing efficiency in a cost-effective manner.
Polymer published new progress about 121-79-9. 121-79-9 belongs to esters-buliding-blocks, auxiliary class Natural product, name is Propyl 3,4,5-trihydroxybenzoate, and the molecular formula is C10H12O5, Safety of Propyl 3,4,5-trihydroxybenzoate.
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