Strong Autonomic Self-Healing Biobased Polyamide Elastomers

Abstract

Autonomic self-healing materials can self-heal without external stimuli and exterior agents. However, most of these materials have inferior mechanical strength. We reported a class of biobased polyamide elastomers as strong autonomic self-healing materials. A high density of hydrogen bonds, chain entanglements, and rigid crystalline domains provide these elastomers with high tensile strength (21.4 MPa) and high toughness (37.5 MJ/m 3 ). The coexistence of a dynamic H-bonding network and olefin cross-metathesis in the amorphous matrix dictates the outstanding autonomic self-healing behavior with ∼100% scratch recovery. The self-healed elastomers show a recovery of ultimate tensile strength, elongation at break, and tensile toughness at 87.8%, 109%, and 86.4%, respectively.

Versatile Phosphate Diester-Based Flame Retardant Vitrimers via Catalyst-Free Mixed Transesterification

“…In contrast, due to the presence of phosphate diesters, the P–OH groups interacted with C=O bonds of carboxylate esters and formed abundant hydrogen bonds within the BPA networks, which can be confirmed by the FTIR absorption peak of bonded C=O structures ( Figure 1 b). 35 These abundant hydrogen bonds together with the high glass transition temperature ( T g ) (152.4 °C) and high cross-linking density (7.1 × 10 3 mol/m 3 ) lead to a mechanically robust thermoset network ( Figure 1 c). Figure 1 d compares the tensile stress–strain curves of the HDA and BPA samples.…”

Thermoplastic Polyamide Elastomers: Synthesis, Structures/Properties, and Applications

“…For self‐healing materials, the dynamic non‐covalent bond is the key factor for achieving self‐healing property. [ 106 ] However, it is very difficult for common self‐healing materials to realize the coexistence of high healing efficiency and high mechanical strength because the two properties are always opposite in most instances. [ 71 ] This problem can be well solved via using TPAEs for constructing self‐healing materials because the soft segments with low T g as well as the hydrogen‐bond interaction in TPAEs provide excellent self‐healing capacity; the hard segments contribute sufficiently high mechanical strength.…”

“…Wu and colleagues [ 106 ] synthesized a set of bio‐based TPAEs with outstanding self‐healing performance. The obtained self‐healing TPAEs show high tensile tenacity (37.5 MJ m −3 ) and relatively high tensile strength (21.4 MPa).…”

Long-chain polyamide covalent adaptable networks based on renewable ethylene brassylate and disulfide exchange

“…To prepare such systems, elegant and efficient synthetic routes have been followed, however, they involved some complex synthesis and purification of precursors, use of transition metal catalysts and/or solvents and toxic reagents for the polymerization or crosslinking. [16][17][18][19] Since the seminal work of Leibler and coworkers, 20 a multitude of different bonds, namely esters, 21,22 disulfides, 23,24 imines, 25,26 urethanes 27,28 and boronic esters, 29,30 have been employed for the design of reprocessable networks. Seeking for a simpler and more sustainable alternative towards longchain PA CANs, we focused on disulfides as an intrinsically reactive bond, 31,32 that can be activated under mild conditions.…”