The Synergy of Hydrogen Bond and Entanglement of Elastomer Captures Unprecedented Flaw Insensitivity Rate

Abstract

Elastomers are regarded as one of the best candidates for the matrix material of soft electronics, yet they are susceptible to fracture due to the inevitable flaws generated during applications. Introducing microstructures, sacrificial bonds, and sliding cross‐linking has been recognized as an effective way to improve the flaw insensitivity rate (Rinsen). However, these elastomers still prone to failure under tensile loads with the presence of even small flaws. Here, this work reports a polybutadiene elastomer with unprecedented Rinsen via the synergy of hydrogen bond and entanglement. The resulting polybutadiene elastomer exhibits a Rinsen ≈1.075, which is much higher than those of reported elastomers. By molecular chain interaction and molecular chain conformation analysis, this work demonstrates that the synergistic effect of hydrogen bond dissociation and entanglement slip in the polybutadiene elastomers during stretching leads to the high Rinsen. Using polybutadiene elastomer as matrix of thermal interface materials, this work demonstrates effective heat transfer for strain sensor and electronic devices. In addition, cytocompatibility of the elastomers is verified by cell proliferation and live/dead viability assays. The combination of outstanding biocompatible and excellent mechanical properties of the elastomers creates new opportunities for their applications in electronic skin.

Dual Reversible Network Nanoarchitectonics for Ultrafast Light-Controlled Healable and Tough Polydimethylsiloxane-Based Composite Elastomers

“…A value of C 2 > 0 is attributed to the disassociation of dynamic bonds and the partial movement of polymeric chains, emphasizing the contribution strain softening behavior to high stretchability (Figure c). Furthermore, the tensile stress–strain curve of Fe/FBA@ x % OHCNT can be fitted by a viscoelastic model , (eq ), as shown in Figure S10 (Supporting Information) σ λ = [ 2 G normalv G normale 1 − 2 D normale true( 1 − exp ( − 1 − 2 D normale D e false( λ − 1 false) ) true) + G normalv D normale 1 + D normale true( 1 − exp ( − 1 + D normale D e false( λ − 1 false) ) true) ] λ − 1 + ( G e 1 − false( λ 2 + 2 λ − 1 − 3 false) / false( λ normalm 2 + 2 λ normalm − 1 − 3 false) …”

“…A value of C 2 > 0 is attributed to the disassociation of dynamic bonds and the partial movement of polymeric chains, emphasizing the contribution strain softening behavior to high stretchability (Figure c). Furthermore, the tensile stress–strain curve of Fe/FBA@ x % OHCNT can be fitted by a viscoelastic model , (eq ), as shown in Figure S10 (Supporting Information) where λ m represents the theoretical finite extensibility of polymer chains and D e is the Deborah number. G v and G e are the viscoelastic and elastic parts of the shear modulus, respectively.…”

“…A value of C 2 > 0 is attributed to the disassociation of dynamic bonds and the partial movement of polymeric chains, emphasizing the contribution strain softening behavior to high stretchability 34 (Figure 2c). Furthermore, the tensile stress−strain curve of Fe/FBA@x% OHCNT can be fitted by a viscoelastic model 35,36 (eq 2), as shown in Figure S10 (Supporting Information) (2…”

Phase-Pinned Bicontinuous Structures Reconciling with the Superior Fracture Toughness and Reusability of Ionic Elastomers

“…The σ /G –(λ – λ –2 ) double-logarithmic curves, where G is the shear modulus, reveal that the stretching process is composed of three regions (Figure c). The slope of −1 < lg (λ – λ –2 ) < 0.22 is 0.38, corresponding to the stretching process of flexible curly chains in the percolating phase . In this process, the ionic bonds suppress the interphase slippage and disperse the applied loads to the whole networks.…”

Self-healing polymers through hydrogen-bond cross-linking: synthesis and electronic applications

“…3.3.4 Others. Based on their exceptional mechanical performance and self-healable features, H-bonding-based SHPs have also been employed as a multifunctional electronic device platform, 193 matrix of thermal interface materials, 104,194 and substrate for stretchable electrodes. 50,79,86 For example, Bao and co-workers 50 reported the fabrication of a stretchable and autonomous self-healing electrode using tough and waterinsensitive SHPs as the encapsulation and supporting layer, which exhibited high stretchability (B500%) with stable (100 cycles) and reversible low resistance.…”