Ultrasound healable shape memory dynamic polymers

Lu, Xili; Fei, Guoxia; Xia, Hesheng; Zhao, Yue

doi:10.1039/c4ta02726d

Cited by 110 publications

(110 citation statements)

References 49 publications

Supporting

Mentioning

108

Contrasting

Unclassified

Order By: Relevance

“…Healing scratches by the SM effect has also been investigated for cross-linked polyethylene-carbon black nanocomposites, 23 carbon nanotube-Nafion composites 24 and poly(vinyl butyral) networks. [29][30][31][32] Despite many developed self-healing methods, DA chemistry is still widely used as a promising pathway to construct recyclable and self-healing materials owing to its repeatable thermal response and simple and highly efficient features. Michal et al 26 reported SM polymer networks containing reversible disulfide bonds, which can heal scratches via disulfide exchange reactions under UV light irradiation after thermal SM activation.…”

Section: Introductionmentioning

confidence: 99%

“…27,28 Some research groups have investigated SM polymers containing Diels-Alder (DA) bonds. 29,31,32 In most of these systems, efficient healing required cleavage of the unbroken DA bonds by either heating the specimens at rDA temperatures 30,32 or treating with ultrasound 31 before DA reshuffling reactions, in spite of the shape recovery function. 33,34 As the DA adduct is weaker than other covalent bonds, the DA bonds preferentially cleave by a retro-DA (rDA) reaction when a fracture appears.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Healable shape memory (thio)urethane thermosets

et al. 2015

View full text Add to dashboard Cite

Urethane-thiourethane networks combining shape memory properties and the ability to self-heal under mild temperature conditions via Diels-Alder (DA) chemistry were developed. As a result of the shape recovery effect, no external force was needed to bring the fracture surfaces into intimate contact during the healing process. Four network architectures with DA net-points were evaluated. Two systems were composed of either bismaleimidic or bisfuranic semi-crystallized polycaprolactone chains acting as shape memory switching segments (T trans = T m ), whereas the other two networks consisted of bis-/trismaleimidic and trisfuranic monomers and displayed glass transitions for initiating shape recovery behaviour (T trans = T g ). The formation of the DA cross-links, the DA reversibility and shape memory assisted scratch healing of the materials were studied by FTIR and 1 H-NMR spectrometry, differential scanning calorimetry, optical microscopy and tensile measurements. The results indicated that the healing efficiency of scratches depends strongly on the shape recovery ability, without which crack closure and thus the healing reaction could not occur. Two materials were found to feature good shape memory properties as well as efficient scratch-healing capacities, showing mechanical recoveries of 70-80% and the almost complete disappearance of scratches after healing at a mild temperature of 60°C for 1-3 days. These materials could find applications in diverse fields such as self-healing coatings.Scheme 1 Chemical structures of the (thio)urethane multi-maleimide and multi-furan monomers and schematic depiction of the SM networks reversibly cross-linked by the DA reaction. Polymer Chemistry PaperThis journal is

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Healable shape memory (thio)urethane thermosets

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Thus, an ultrasound-induced directed and localized healing of a poly(ε-caprolactone)-based polyurethane, dynamically crosslinked by DielseAlder chemistry of attached furan and maleimide groups, was reported [36] (see Fig. 4).…”

Section: Void-fillingmentioning

confidence: 96%

“…Reprinted and adopted from Ref. [36] with permission from The Royal Society of Chemistry. enabled fast crosslinking kinetics resulting in irreversibly linked rubbery materials [3,46].…”

Section: Irreversible E Reversible Shmentioning

confidence: 99%

Improving autonomous self healing via combined chemical/physical principles

Michael

Döhler

Binder

2015

Polymer

View full text Add to dashboard Cite

“…3,52,54,55 By turning off the ultrasound beam the shape recovery process can be paused at any time, which allows the polymer to have an intermediate but a stable shape.…”

mentioning

confidence: 99%

Focused ultrasound actuation of shape memory polymers; acoustic-thermoelastic modeling and testing

et al. 2017

View full text Add to dashboard Cite

a Controlled drug delivery (CDD) technologies have received extensive attention recently. Despite recent efforts, drug releasing systems still face major challenges in practice, including low efficiency in releasing the pharmaceutical compounds at the targeted location with a controlled time rate. We present an experimentally-validated acoustic-thermoelastic mathematical framework for modeling the focused ultrasound (FU)-induced thermal actuation of shape memory polymers (SMPs). This paper also investigates the feasibility of using SMPs stimulated by FU for designing CDD systems. SMPs represent a new class of materials that have gained increased attention for designing biocompatible devices. These polymers have the ability of storing a temporary shape and returning to their permanent or original shape when subjected to external stimuli such as heat. In this work, FU is used as a trigger for noninvasively stimulating SMP-based systems. FU has a superior capability to localize the heating effect, thus initiating the shape recovery process only in selected parts of the polymer. The multiphysics model optimizes the design of a SMP-based CDD system through analysis of a filament as a constituting basestructure and quantifies its activation under FU. Experimental validations are performed using a SMP filament submerged in water coupled with the acoustic waves generated by a FU transducer. The modeling results are used to examine and optimize parameters such as medium properties, input power and frequency, location, geometry and chemical composition of the SMP to achieve favorable shape recovery of a potential drug delivery system.

show abstract

Ultrasound healable shape memory dynamic polymers

Cited by 110 publications

References 49 publications

Healable shape memory (thio)urethane thermosets

Healable shape memory (thio)urethane thermosets

Improving autonomous self healing via combined chemical/physical principles

Focused ultrasound actuation of shape memory polymers; acoustic-thermoelastic modeling and testing

Contact Info

Product

Resources

About