Chen, Xi; Hu, Sumeng; Li, Lingqiao; Torkelson, John M. published the artcile< Dynamic Covalent Polyurethane Networks with Excellent Property and Cross-Link Density Recovery after Recycling and Potential for Monomer Recovery>, Synthetic Route of 112-63-0, the main research area is dynamic covalent polyurethane network crosslink density recovery recycling; tensile polyurethane recycling alcoholysis.
Dynamic urethane chem., which involves both associative and dissociative mechanisms, can be used to achieve reprocessability in cross-linked polyurethane (PU) networks. We discovered that property recovery and thermal stability of dynamic covalent PU networks can be enhanced by incorporating excess free hydroxyl groups, and thus performing polymerization reactions at slight stoichiometric imbalance of hydroxyl and isocyanate groups, and by increasing the crosslinker functionality from three to four. While free hydroxyl groups suppress the reversion of urethane links and minimize side reactions associated with liberated isocyanate groups under reprocessing conditions, tetrafunctional crosslinkers help to maintain network integrity in the presence of small levels of side reactions. Using these strategies, we developed a PU network that, within exptl. error, exhibits 100% recovery of crosslink d. and tensile properties after multiple reprocessing steps, which has not been reported before. We also demonstrated the potential of recovering monomer from PU networks by alcoholysis under relatively mild conditions. Our study not only offers a solution to the long-standing issue of PU network recycling, but also provides simple strategies to improve property recovery of reprocessable networks.
ACS Applied Polymer Materials published new progress about Complex modulus, tan δ. 112-63-0 belongs to class esters-buliding-blocks, and the molecular formula is C19H34O2, Synthetic Route of 112-63-0.
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics