Entropy-Driven Design of Highly Impact-Stiffening Supramolecular Polymer Networks with Salt-Bridge Hydrogen Bonds

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(11), С. 7533 - 7542

Опубликована: Март 7, 2024

Impact-stiffening materials that undergo a strain rate-induced soft-to-rigid transition hold great promise as soft armors in the protection of human body and equipment. However, current impact-stiffening materials, such polyborosiloxanes shear-thickening fluids, often exhibit limited response. Herein, we propose design strategy for fabricating highly supramolecular polymer networks by leveraging high-entropy-penalty physical interactions. We synthesized fully biobased comprising poly(α-thioctic acid) arginine clusters, whose chain dynamics are governed specific guanidinium-carboxylate salt-bridge hydrogen bonds. The resulting material exhibits an exceptional response ∼2100 times, transitioning from dissipating state (21 kPa, 0.1 Hz) to stiffened glassy (45.3 MPa, 100 with increasing rates. Moreover, material's high energy-dissipating hot-melting properties bring excellent damping performance easy hybridization other scaffolds. This entropy-driven approach paves way development next-generation soft, sustainable, impact-resistant materials.

Язык: Английский

---

In Situ Structural Densification of Hydrogel Network and Its Interface with Electrodes for High-Performance Multimodal Artificial Skin

ACS Nano, Год журнала: 2024, Номер 18(24), С. 15754 - 15768

Опубликована: Июнь 3, 2024

The multisensory responsiveness of hydrogels positions them as promising candidates for artificial skin, whereas the mismatch modulus between soft and hard electrodes well poor adhesion conductance at interface greatly impairs stability electronics devices. Herein, we propose an in situ postprocessing approach utilizing electrochemical reactions metals (Zn, etc.) to synergistically achieve strong hydrogel-electrode interface, low interfacial impedance, local strain isolation due structural densification hydrogel network. mechanism is that Zn electrochemically oxidizes

Язык: Английский

---

High‐Toughness CO₂‐Sourced Ionic Polyurea Adhesives

Advanced Materials, Год журнала: 2024, Номер 36(16)

Опубликована: Янв. 11, 2024

Abstract Polyurea (PUa) adhesives are renowned for their exceptional adhesion to diverse substrates even in harsh environments. However, the presence of quadruple bidentate intermolecular hydrogen bonds polymer chains creates a trade‐off between cohesive energy and interfacial adhesive energy. To overcome this challenge, series CO 2 ‐sourced ionic PUa with ultratough various developed. The incorporated segments within serve partially mitigate bonding interactions while conferring unique electrostatic interactions, leading both high maximum strength 10.9 MPa can be attained by ionizing using bromopropane subsequently exchanging anion lithium bis(trifluoromethylsulfonyl)imide. Additionally, these demonstrate several desirable properties such as low‐temperature stability (−80 °C), resistance organic solvents water, flame retardancy, antibacterial activity, UV‐fluorescence, thereby expanding potential applications. This study presents general effective approach designing high‐strength suitable wide array uses.

Язык: Английский

---

Ultrastrong and Thermo‐Remoldable Lignin‐Based Polyurethane Foam Insulation with Active‐Passive Fire Resistance

Advanced Functional Materials, Год журнала: 2024, Номер 34(40)

Опубликована: Июнь 19, 2024

Abstract Foam thermal insulators are indispensable for prevailing energy‐saving engineering, however their widespread use brings intractability such as unsustainability, “white pollution”, and fire hazards. The emergence of bio‐based foams is highly appreciated, but the fabrication approaches economically unattractive and/or product properties inferior, making large‐scale implementation unviable. Herein, a versatile, thermally remoldable phosphate‐containing polyurethane composite foam (LPU‐G) constructed from natural lignin expanded graphite flakes via an atmospheric pressure scalable one‐pot strategy. optimal LPU‐G exhibits exceptional mechanical strength, capable supporting over 6000 times its weight without significant deformation. Moreover, demonstrates desired multifunctionality in handling extreme circumstances, including humidity‐tolerant insulation, superb water vapor barrier, withstanding ≈1200 °C flame ignition. Based on “expansion‐conductivity” micro‐mechanism, first material to be sensitive alarm system with ultra‐long time (>1800 s). Surprisingly, can rapidly upcycled into recyclable bulk composites second life through simple thermo‐molding processes rooted multi‐dynamic behavior phosphate, carbamate, hydrogen bonds. easy‐to‐scale represents new generation that address concerns regarding high cost, risk, inferior properties.

Язык: Английский

---

Bioinspired Green Underwater Adhesive Gelatin‐Tannic Acid Hydrogel With Wide Range Adjustable Adhesion Strength and Multiple Environmental Adaptability

Advanced Functional Materials, Год журнала: 2024, Номер 35(2)

Опубликована: Авг. 29, 2024

Abstract Underwater adhesion of hydrogels is essential for their applications in liquid environment. However, green raw materials, facile preparation process and multiple environmental adaptability are still issues that need to be improved. Inspired by the protein‐based underwater bio‐adhesion phenomena nature, an effective stepwise immersion method developed without any polymerization prepare a adhesive hydrogel combining gelatin tannic acid (TA), two common materials from nature yet difficult obtain homogenous compound. By treatments urea solution or heating, can realize stable immediate on various substrates different liquids addition water with wide range adjustable strength 10 0 –10 3 kPa. The evolution network structure mechanism systematically studied. Furthermore, several typical portable products based demonstrated show commercialization possibility. This work presented novel, facile, distinctive strategy designing environmentally friendly, adaptive adhesives.

Язык: Английский

---

Sea Cucumber‐Inspired Polyurethane Demonstrating Record‐Breaking Mechanical Properties in Room‐Temperature Self‐Healing Ionogels

Advanced Materials, Год журнала: 2024, Номер 36(44)

Опубликована: Сен. 12, 2024

Abstract Practical applications of existing self‐healing ionogels are often hindered by the trade‐off between their mechanical robustness, ionic conductivity, and temperature requirements for ability. Herein, this challenge is addressed drawing inspiration from sea cucumber. A polyurethane containing multiple hydrogen‐bond donors acceptors synthesized used to fabricate room‐temperature with excellent properties, high puncture resistance, impact resistance. The hard segments polyurethane, driven hydrogen bonds, coalesce into phase regions, which can efficiently dissipate energy through reversible disruption reformation bonds. Consequently, resulting exhibit record‐high tensile strength toughness compared other ionogels. Furthermore, inherent reversibility bonds within regions allows spontaneously self‐heal damaged properties conductivity times at room temperature. To underscore application potential, these employed as electrolytes in fabrication electrochromic devices, stable performance, repeatable healing ability, satisfactory This study presents a novel strategy exceptional capability.

Язык: Английский

---

All‐In‐One Photonic Crystals With Multi‐Stimuli‐Chromic, Color‐Recordable, Self‐Healable, and Adhesive Functions

Advanced Functional Materials, Год журнала: 2024, Номер unknown

Опубликована: Окт. 15, 2024

Abstract Fabricating photonic crystals (PCs) with dynamic multi‐stimuli‐responsive structural colors, recordable and self‐healable properties is significant for their emerging applications, yet remains a big challenge. Here, an all‐in‐one multifunctional PC (MFPC) film outstanding mechanochromic, thermochromic, solvatochromic, color/shape‐recordable, self‐healable, adhesive functions designed prepared by simply non‐close‐assembling silica particles into the unique 2‐[[(Butylamino)carbonyl]oxy]ethyl acrylate (BCOEA) followed photopolymerization. The success mainly due to rational combination of non‐close‐packing structures BCOEA's characteristics, including its urethane groups numerous sacrificial hydrogen bonds, temperature‐dependent refractive index, swellable deformable polymer network, as well low glass‐transition temperature. MFPC's hue color saturation can be reversibly dynamically modulated strain/pressure/solvents temperature, respectively, thereby realizing visually spectrally sensing these stimuli. More interestingly, color‐responsiveness combined other endows MFPCs fascinating multilayer optical filters, inkless printing, reconfigurable multicolor patterns, stretching‐based anti‐counterfeiting, etc. This work offers new perspective designing next‐generation smart materials will facilitate all‐round applications.

Язык: Английский

---

Mechanical Regulation of Polymer Gels

Chemical Reviews, Год журнала: 2024, Номер 124(18), С. 10435 - 10508

Опубликована: Сен. 16, 2024

The mechanical properties of polymer gels devote to emerging devices and machines in fields such as biomedical engineering, flexible bioelectronics, biomimetic actuators, energy harvesters. Coupling network architectures interactions has been explored regulate supportive characteristics gels; however, systematic reviews correlating mechanics interaction forces at the molecular structural levels remain absent field. This review highlights engineering gel a comprehensive mechanistic understanding regulation. Molecular alters architecture manipulates functional groups/moieties level, introducing various permanent or reversible dynamic bonds dissipative energy. usually uses monomers, cross-linkers, chains, other additives. Structural utilizes casting methods, solvent phase regulation, mechanochemistry, macromolecule chemical reactions, biomanufacturing technology construct tailor topological structures, heterogeneous modulus compositions. We envision that perfect combination may provide fresh view extend exciting new perspectives this burgeoning also summarizes recent representative applications with excellent properties. Conclusions are provided from five aspects concise summary, mechanism, biofabrication upgraded applications, synergistic methodology.

Язык: Английский

---

Hydrogen Bonding Competition Mediated Phase Separation with Abnormal Moisture‐Induced Stiffness Boosting

Small, Год журнала: 2024, Номер unknown

Опубликована: Май 3, 2024

Abstract Moisture usually deteriorates polymers’ mechanical performance owing to its plasticizing effect, causing side effects in their practical load‐bearing applications. Herein, a simple binary ionogel consisting of an amphiphilic polymer network and hydrophobic ionic liquid (IL) is developed with remarkable stiffening effect after moisture absorption, demonstrating complete contrast water‐induced softening most materials. Such moisture‐induced behavior induced by phase separation hydration this ionogel. Specifically, it revealed that hydrogen (H)‐bonding structures play dominant role the humidity‐responsive ionogel, where water will preferentially interact chains through H‐bonding break polymer‐IL H‐bonds, thus leading modulus boosting. This work may provide facile effective molecular engineering route construct mechanically adaptive polymers dramatic for diverse

Язык: Английский

---

Ionic Gel Electrolytes for Electrochromic Devices

ACS Applied Materials & Interfaces, Год журнала: 2024, Номер 16(37), С. 48927 - 48936

Опубликована: Сен. 6, 2024

Ionic gels are emerging as a promising solution for improving the functionality of electrochromic devices. They increasingly drawing attention in fields electrochemistry and functional materials due to their potential address issues associated with traditional liquid electrolytes, such volatility, toxicity, leakage. In extreme scenarios and/or design flexible devices, ionic gel electrolytes offer unique invaluable advantages. This perspective delves into application exploring various methods enhance performance. After briefly introducing developments trends key points future development discussed detail.

Язык: Английский

---