/pdf/highly-stretchable-elastic-and-ionic-conductive-hydrogel-for-353blx5mo6.pdf

Highly Stretchable, Elastic, and Ionic Conductive Hydrogel for Artificial Soft Electronics

The design and synthesis of double network (DN) hydrogels that can mimic the properties and/or structure of natural tissue has flourished in recent years, overcoming the bottlenecks of mechanical performance of single network hydrogels and extending their potential applications in various fields. In recent years, such bioinspired DN hydrogels with extraordinary mechanical performance, excellent biocompatibility, and considerable strength have been demonstrated to be promising candidates for biomedical applications, such as tissue engineering and biomedicine. In this minireview, we provide an overview of the recent developments of bioinspired DN hydrogels defined as DN hydrogels that mimic the properties and/or structure of natural tissue, ranging from, e.g., anisotropically structured DN hydrogels, via ultratough energy dissipating DN hydrogels to dynamic, reshapable DN hydrogels. Furthermore, we discuss future perspectives of bioinspired DN hydrogels for biomedical applications.

Bioinspired double network hydrogels: from covalent double network hydrogels via hybrid double network hydrogels to physical double network hydrogels

Self-healing gels, which are able to restore their original shape/condition after damage, have recently attracted considerable interest. The present review provides an update on the current status of self-healing gels for use in soft self-healing devices, with the main focus on wearable devices. Following a brief introduction of conventional self-healing gels, this review summarizes the current strategies for synthesizing self-healing gels, comparing the properties of polymeric and small molecular self-healing gels. Some of the strengths and weaknesses of these two types of self-healing gels are clearly highlighted. Several typical instances to outline the emerging applications of self-healing gels with partially or fully self-healing devices/materials, including wearable sensors, supercapacitors, lithium batteries, and coatings, are provided. Finally, the current challenges and future perspectives regarding the further development of self-healing gels are also discussed.

Self-Healable Gels for Use in Wearable Devices

This review is focused on the most recent research on multifunctional shape memory polymer nanocomposites reinforced by various nanoparticles. Different multifunctional shape memory nanocomposites responsive to different kinds of stimulation methods, including thermal responsive, electro-activated, alternating magnetic field responsive, light sensitive and water induced SMPs, are discussed separately. This review offers a comprehensive discussion on the mechanism, advantages and disadvantages of each actuation methods. In addition to presenting the micro- and macro- morphology and mechanical properties of shape memory polymer nanocomposites, this review demonstrates the shape memory performance and the potential applications of multifunctional shape memory polymer nanocomposites under different stimulation methods.

Stimulus methods of multi-functional shape memory polymer nanocomposites: A review

Chemically linked double network (DN) hydrogels display extraordinary mechanical attributes but mostly suffer from poor self-healing property and unsatisfactory biocompatibility due to the irreversible breaks in their chemical-linked networks and the use of toxic chemical cross-linking agents. To address these limitations, we developed a novel κ-carrageenan/polyacrylamide (KC/PAM) DN hydrogel through a dual physical-cross-linking strategy, with the ductile, hydrophobically associated PAM being the first network, and the rigid potassium ion (K+) cross-linked KC being the second network. The dual physically cross-linked DN (DPC-DN) hydrogels with optimized KC concentration exhibit excellent fracture tensile stress (1320 ± 46 kPa) and toughness (fracture energy: 6900 ± 280 kJ/m3), comparable to those fully chemically linked DN hydrogels and physically chemically cross-linked hybrid DN hydrogels. Moreover, because of their unique dual physical-cross-linking structures, the KC/PAM hydrogels also demonstrated r...

/pdf/dual-physically-cross-linked-k-carrageenan-based-double-6venmsbu1d.pdf

Dual Physically Cross-Linked κ Carrageenan-Based Double Network Hydrogels with Superior Self-Healing Performance for Biomedical Application

This work aimed to develop a facile and broadly applicable method for fabricating multistimuli responsive triple-shape memory polymers (SMPs). Hence, herein the SMPs were prepared through the simple physical blending of two commercially available biopolymers, poly(lactic acid) (PLA) and poly(vinyl acetate) (PVAc), in the presence of robust and conductive graphene nanoplatelets. Interestingly, atomic force microscopy observations and thermal analyses revealed that the presence of nanofillers led to phase separation and appearance of two well-separated transition temperatures in the blend of these two miscible polymers. Consequently, shape memory results showed that the unfilled blend of PLA/PVAc with a single thermal transition can only show moderate heat triggered dual-shape memory behavior. While, PLA/PVAc/graphene nanocomposite blends demonstrated excellent thermally and electrically actuated triple-shape memory effects besides their remarkable dual-shape memory behavior. In addition, electrical conductivity of the blend was enhanced by ∼14 orders of magnitude in the presence of graphene. More interestingly, electroactive shape recovery experiments exhibited that depending on the applied voltage, temporary shapes in each region of sample can be either individually or simultaneously recovered.

Thermally and Electrically Triggered Triple-Shape Memory Behavior of Poly(vinyl acetate)/Poly(lactic acid) Due to Graphene-Induced Phase Separation

pH-dependent swelling and antibiotic release from citric acid crosslinked poly(vinyl alcohol) (PVA)/nano silver hydrogels.

/pdf/bioinspired-fully-physically-cross-linked-double-network-5dxmmqm4vc.pdf

Masoud Babaahmadi

Papers

Thermally and Electrically Triggered Triple-Shape Memory Behavior of Poly(vinyl acetate)/Poly(lactic acid) Due to Graphene-Induced Phase Separation

pH-dependent swelling and antibiotic release from citric acid crosslinked poly(vinyl alcohol) (PVA)/nano silver hydrogels.

Bioinspired fully physically cross-linked double network hydrogels with a robust, tough and self-healing structure

Self-healing and tough hydrogels with physically cross-linked triple networks based on Agar/PVA/Graphene.

Preparation of amorphous nanocomposites with quick heat triggered shape memory behavior