A novel kind of room temperature self-healing poly(urethane-urea) with robust mechanical strength based on aromatic disulfide

Abstract

An innovative poly(urethane-urea) elastomer, which exhibited excellent stretchability, thermal stability and autonomous self-healing abilities, was synthesized from the commercially available poly(propylene glycol) (PPG), isophorone diisocyanate (IPDI), 2,4 / 2,6-toluene diisocyanate (80: 20, w / w) (TDI-80) and bis (2-aminophenyl) disulfide (DSDA). This aromatic disulfide containing poly(urethane-urea) (ss-PUs) achieved both rapid room temperature self-healing abilities and robust mechanical strength (the ultimate tensile strength was up to 4.20 ± 0.10 MPa and elongation at break was up to 954 ± 35.6%), through facile metathesis of the aromatic disulfides which embedded in hard segments. After the ss-PUs was cut into two-halves and reconnected, the mechanical properties could recover to ~ 90% of those of the original samples within 12 h at room temperature without extra self-healing agents or any change of environmental conditions.

A bio-based thermoplastic polyurethane with triple self-healing action for wearable technology and smart textiles

“…The glass transition temperature, T g , of the synthesised TPUs, determined as the onset of the transition, were −6.6 °C, −3.7 °C and −1.4 °C for P35, P40 and P45, respectively, slightly high compared with other self-healing or bio-based TPUs, which show a T g value as low as −45 °C. 33,34 The short length of the diol increases the T g value. 35 The higher T g value of the TPUs is not a limitation for self-healing, as the values are lower than RT.…”

Low-Temperature Self-Healing Supramolecular Zinc-Poly(Urea–Urethane) Elastomer

“…At −40 °C, the repair efficiencies of the samples can attain 12.1, 20.3, 37.6, and 65.3% (Table S3). The repair rate is the highest among the previously reported self-repairing elastomers with tensile strength similar to that of this work ,,,− (Figures c,d and S7), which indicates that the as-prepared HPDPU-Zn samples possess rapid self-repairing ability. In addition, the self-repair efficiencies of the HPDPU-Zn-0.5 samples are maintained >90% at 25 and −40 °C for 12 h. This excellent self-repairing performance of the elastomers at low temperatures can be attributed to the following features: (1) copolymerization and the addition of the DAP chain extender prevented the crystallization of the polymer network and improved the low-temperature molecular chain fluidity of the polymer.…”

Transparent and Self‐Healing Elastomers for Reconfigurable 3D Materials

“…The storage modulus ( G ′) at linear viscoelastic region (a strain of 0.1%) of pristine and after cycles of deformation was not significantly different (≈0.10–0.11 MPa) as shown in (Figure S4c, Supporting Information), implying that the viscoelastic properties of the PU‐SH polymer did not change after being deformed several times. G ′ of the self‐healing polymer (PU‐SH) was larger than for self‐healing poly(urethane‐urea) [ 47 ] ( G ′ = 0.2 MPa) and thermoplastic polyurethanes [ 48,49 ] ( G ′ = 0.01–0.015 MPa) at an oscillatory strain of 0.1% at 25 °C. Objects with this polymer could be reconfigured several times without loss of viscoelastic properties.…”