Dynamic Nanoconfinement Enabled Highly Stretchable and Supratough Polymeric Materials with Desirable Healability and Biocompatibility

Abstract

such as aerospace, transportation, and biological engineering. [2,3] In general, the combination of great toughness, large ductility, and high strength in polymers is essential for enabling their real-world applications. However, existing strengthening and/or toughening strategies fail to realize the desirable mechanical combination in polymers owing to mutually exclusive governing mechanisms between strength and modulus. [4] In addition, the ability to self-heal is another desirable yet key factor for extending their lifespan after damage, [5][6][7] whereas a good biocompatibility is a prerequisite for their practical applications as artificial tissues. For example, in addition to the lack of a selfhealing ability, existing artificial ligament materials usually suffer from lower ductility and/or toughness relative to natural counterparts. [8,9] Therefore, it has been highly attractive but remained a grand challenge to create strong, tough, and ductile polymeric materials that are also healable and biocompatible so far.Many natural materials such as nacre, [10,11] bones, [12] and spider silk fibers (SSF) [13] are valid examples of how the evolutionary forces address the issue of the trade-off between mechanical strength and stretchability. In particular, SSF exhibits an outstanding fracture toughness over 150 J g −1 and a large breaking strain (>50%) as well as high tensile strength (>1 GPa). [14] The unique mechanical combination has been revealed to originate from Lightweight polymeric materials are highly attractive platforms for many potential industrial applications in aerospace, soft robots, and biological engineering fields. For these real-world applications, it is vital for them to exhibit a desirable combination of great toughness, large ductility, and high strength together with desired healability and biocompatibility. However, existing material design strategies usually fail to achieve such a performance portfolio owing to their different and even mutually exclusive governing mechanisms. To overcome these hurdles, herein, for the first time a dynamic hydrogen-bonded nanoconfinement concept is proposed, and the design of highly stretchable and supratough biocompatible poly(vinyl alcohol) (PVA) with well-dispersed dynamic nanoconfinement phases induced by hydrogenbond (H-bond) crosslinking is demonstrated. Because of H-bond crosslinking and dynamic nanoconfinement, the as-prepared PVA nanocomposite film exhibits a world-record toughness of 425 ± 31 MJ m −3 in combination with a tensile strength of 98 MPa and a large break strain of 550%, representing the best of its kind and even outperforming most natural and artificial materials. In addition, the final polymer exhibits a good self-healing ability and biocompatibility. This work affords new opportunities for creating mechanically robust, healable, and biocompatible polymeric materials, which hold great promise for applications, such as soft robots and artificial ligaments.

Functionalizing mesoporous silica with a nano metal–organic phosphonate towards mechanical‐robust, thermal‐resistant, and fire‐safety epoxy resin

“…At the same dosage, mSiO 2 imparts biggest promotion on the T g of EP composite from 163 to 169°C, higher than the cases of TETP (168°C) and mSiO 2 @TETP (168°C). The augmentation of the T g of EP/mSiO 2 ‐3 is possibly caused by the intermolecular interactions between the hydroxyls on the surfaces of mSiO 2 and the hydroxyls produced from the ring opening of epoxy, where the partial crosslinking density is increased and the crosslinking networks limit the segmental movement of EP chains 47,53,54 . Moreover, the possibility of the assimilation of the organic species of EP into the ordered mesoporous of mSiO 2 can further promotes the intermolecular interactions between the hydroxyls of mSiO 2 and epoxy, as reported by Choi 55 .…”

“…The augmentation of the T g of EP/mSiO 2 -3 is possibly caused by the intermolecular interactions between the hydroxyls on the surfaces of mSiO 2 and the hydroxyls produced from the ring opening of epoxy, where the partial crosslinking density is increased and the crosslinking networks limit the segmental movement of EP chains. 47,53,54 Moreover, the possibility of the assimilation of the organic species of EP into the ordered mesoporous of mSiO 2 can further promotes the intermolecular interactions between the hydroxyls of mSiO 2 and epoxy, as reported by Choi. 55 As for TETP, the organic groups lead to a good interfacial compatibility between TETP and epoxy, where TETP acts as the physical crosslinkers to…”

Grafting alkynyl groups on the surface of nano‐aramid fibers towards flame retardant thermoplastic polyurethane

“…The reason for this phenomenon was that the ANF solution was alkaline, which damaged the molecular chains of TPU 34 . The added ANF‐PC was cross‐linked to the TPU chains through hydrogen bonding, forming a high‐strength cross‐linked structure that could be uniformly dispersed in the composite 49 . When external stress forced the TPU/ANF‐PC to deform, this cross‐linked structure changed its dimensions by breaking and reorganizing the hydrogen bonds, which in turn enhanced the strength of the composite.…”

“…hydrogen bonding, forming a high-strength cross-linked structure that could be uniformly dispersed in the composite 49. When external stress forced the TPU/ANF-PC to deform, this cross-linked structure changed its dimensions by breaking and reorganizing the hydrogen bonds, which in turn enhanced the strength of the composite.…”

Strong, Healable, Stimulus‐Responsive Fluorescent Elastomers Based on Assembled Borate Dynamic Nanostructures

“…Endowing materials with skin-like self-healing performance is a fascinating approach to expand their applications and prolong service life, especially the expensive functional materials with delicate nanostructures. [1][2][3] Although exquisite supramolecular networks such as multiple dynamic bonds, [4,5] covalent and noncovalent interpenetrated networks, [6] have been designed, materials with excellent healing efficiency and mechanical performance are hard to achieve because of the inherent conflict between stiffness and mobility of molecular chains. To date, nanostructures are easily integrated into polyols substrates via interfacial borate dynamic crosslinks, permitting development of self-healing material with various functions.…”