Interpenetrating Polymer Networks Research Articles

3D printing of gellan-dextran methacrylate IPNs in glycerol and their bioadhesion by RGD derivatives.

The ever-growing need for new tissue and organ replacement approaches paved the way for tissue engineering. Successful tissue regeneration requires an appropriate scaffold, which allows cell adhesion and provides mechanical support during tissue repair. In this light, an interpenetrating polymer network (IPN) system based on biocompatible polysaccharides, dextran (Dex) and gellan (Ge), was designed and proposed as a surface that facilitates cell adhesion in tissue engineering applications. The new matrix was developed in glycerol, an unconventional solvent, before the chemical functionalization of the polymer backbone, which provides the system with enhanced properties, such as increased stiffness and bioadhesiveness. Dex was modified introducing methacrylic groups, which are known to be sensitive to UV light. At the same time, Ge was functionalized with RGD moieties, known as promoters for cell adhesion. The printability of the systems was evaluated by exploiting the ability of glycerol to act as a co-initiator in the process, speeding up the kinetics of crosslinking. Following semi-IPNs formation, the solvent was removed by extensive solvent exchange with HEPES and CaCl2, leading to conversion into IPNs due to the ionic gelation of Ge chains. Mechanical properties were investigated and IPNs ability to promote osteoblasts adhesion was evaluated on thin-layer, 3D-printed disk films. Our results show a significant increase in adhesion on hydrogels decorated with RGD moieties, where osteoblasts adopted the spindle-shaped morphology typical of adherent mesenchymal cells. Our findings support the use of RGD-decorated Ge/Dex IPNs as new matrices able to support and facilitate cell adhesion in the perspective of bone tissue regeneration.

Rapid tooling for rubber extrusion molding by digital light processing 3D printing with dual curable vitrimers

AbstractFor the manufacture of extrusion dies, three‐dimensional (3D) printing with photopolymers offers numerous advantages including flexibility, high surface quality, decent build speed, low costs and a reduced amount of waste. However, the majority of photocurable resins used in vat photopolymerization 3D printing rely on acrylates, which entail 3D‐printed objects with poor mechanical properties. In particular, the high brittleness limits their application in rapid tooling, for which tough materials with high glass transition temperatures (Tg) are required. In the present study, we highlight the use of dual curable acrylate‐epoxy resins with dynamic covalent bonds for the direct fabrication of extrusion dies. During digital light processing (DLP) 3D printing the acrylate network is formed, whose toughness and thermal stability are significantly enhanced by the thermoactivated formation of a second network. By following a postbaking procedure, aminoglycidiyl monomers are cured with an anhydride hardener bearing bulky norbornene groups yielding interpenetrating polymer networks with a Tg > 100°C. The tertiary amine groups present in the structure of the aminoglycidyl derivatives do not only accelerate the ring‐opening reaction but also act as internal catalysts and activate bond exchange reactions between free –OH groups and ester moieties available in the photopolymer. This is confirmed by rheometer studies showing a distinctive stress relaxation at elevated temperature and giving rise to a possible reprocessability of the 3D‐printed dies. With a selected resin formulation, a set of dies is printed by DLP 3D printing, with which a highly filled rubber compound is successfully extruded. The results clearly show that dual curable resins with dynamic covalent bonds are a promising class of material for rapid tooling and pave the way towards a customized and convenient fabrication of extrusion dies for rubber processing.

Experimental comparative study of a novel drug-eluting arteriovenous graft in a sheep model.

Arteriovenous (AV) grafts often develop severe complications of stenosis due to neointimal proliferation that occurs either at the venous anastomosis site or at the outflow receiving vein. This study compares primary patency during 12 months of follow up for a new experimental Biomodics© interpenetrating polymer network (IPN) drug-eluting graft prototype with state-of-the-art GORE® ACUSEAL (ACUSEAL) in an AV graft model in sheep. An end-to-end bypass from the common carotid artery to the jugularis vein was performed bilaterally in 12 sheep. The usage of ACUSEAL or the IPN, both 6.0 mm in diameter, was determined via randomization. The sheep were followed up every 4 weeks with ultrasonic duplex scanning to determine patency; the experienced observer was blinded to the randomization. One sheep died after 11 days, and the final sample accordingly consisted of 11 animals. When comparing neointimal hyperplasia after 12 months in the two grafts, Fisher's exact test showed a significant difference with none out of 11 in the IPN grafts and 9 out of 11 in the ACUSEAL graft (p < 0.001). However, the Biomodics© IPN exhibited severe deterioration over time. Almost all of the grafts occluded during the 12 months of follow up. Although the zwitterion-bounded interpenetrating drug eluting polymer network showed signs to impair neointimal hyperplasia and thrombosis, age-related degeneration hindered demonstrating a potential improvement in patency.

Production of Sequential Interpenetrating Polymer Networks from Ximenia americana Seed Oil-based Polyurethanes and Polystyrene

Interpenetrating polymer network are combinations of two or more polymer in network form. The objective of this paper was to evaluate the production and characterization of sequential polyurethane-polystyrene interpenetrating polymer networks from different diisocyanates and varied styrene content using Ximenia americana seed oil as base material. The polymer networks were characterized for their Tensile, Swelling and Thermal properties. The tensile strength and tensile modulus for MDPU-1.50-PS polymer networks, 57.86 ±5.42 - 422.85±15.25 MPa and 2.26±0.91 - 11.08±4.21 MPa respectively are higher than the values represented for HDPU-1.50-PS and TDPU-1.50-PS polymer networks, but the latter polymer networks are higher in values for elongation at break than the former. This is also corroborated by the swelling mass ratio (qm) with values for HDPU-1.50-PS and TDPU-1.50-PS networks higher than those for MDPU-1.50-PS, consistent with lower polystyrene crosslinks in the former polymer networks. Thermal studies present HDPU-1.50-PS-20 as the most stable network at 10% degradation, but at higher degradation temperatures MDPU-1.50-PS-20 polymer network shows stability up to 6000C with 19.40g residual weight of char polymer. This study shows that derivatised Ximenia americana seed oil is suitable as starting material for preparation of an interpenetrating polymer network.

Low-temperature crosslinking characteristics of interpenetrating polymer networks with dual-curable amine-based blocked isocyanate for automotive 1 K clearcoats

Interpenetrating polymer network (IPN) clearcoat systems were developed using two distinct thermal crosslinking reactions: urethane formation reaction and free radical polymerization. Specifically, an amine-based dual-curable blocked isocyanate crosslinker (BITBEMA) was employed to establish additional independent networks within IPNs by utilizing dissociated blocking groups through free radical polymerization. To validate the formation of the IPN and its suitability for a low-temperature curing process, the thermal deblocking characteristics and crosslinking dynamics of the dual-curable 1 K clearcoat were confirmed via various experimental methods, including rheological tests, thermogravimetric analyses, dynamic mechanical analyses, and nano-indentation tests. The influence of the IPNs on the crosslinking characteristics was examined and compared with clearcoat systems featuring only a urethane formation network. Both semi-IPN and full-IPN configurations demonstrated enhanced thermal and mechanical properties in contrast to the mono-curable 1 K clearcoat system, especially at low curing temperatures.

Biobased Interpenetrating Polymer Network Membranes for Sustainable Molecular Sieving.

There is an urgent need for sustainable alternatives to fossil-based polymer materials. Through nanodomain engineering, we developed, without using toxic cross-linking agents, interpenetrating biopolymer network membranes from natural compounds that have opposing polarity in water. Agarose and natural rubber latex were consecutively self-assembled and self-cross-linked to form patchlike nanodomains. Both nano-Fourier transform infrared (nano-FTIR) spectroscopy and computational methods revealed the biopolymers' molecular-level entanglement. The membranes exhibited excellent solvent resistance and offered tunable molecular sieving. We demonstrated control over separation performance in the range of 227-623 g mol-1 via two methodologies: adjusting the molecular composition of the membranes and activating them in water. A carcinogenic impurity at a concentration of 5 ppm, which corresponds to the threshold of toxicological concern, was successfully purged at a negligible 0.56% pharmaceutical loss. The biodegradable nature of the membranes enables an environmentally friendly end-of-life phase; therefore, the membranes have a sustainable lifecycle from cradle to grave.

Suppressive Photochromism and Promotive Mechanochromism of Rhodamine Mechanophore by the Strategy of Poly(methyl acrylate)/Polyurethane Interpenetrating Polymer Network.

As molecular design and the structure-property relationships of photochemical molecules established in the literature serve as a convenient reference for mechanophore exploration, many typical mechanophores suffer undesired responses to UV light or even sunlight in bulk polymers. We developed a strategy of a poly(methyl acrylate)/polyurethane (PMA/PU) interpenetrating polymer network (IPN) to suppress the photochromic property of the mechanophore and promote its mechanochromic property. A widely used rhodamine mechanophore (Rh-2OH) was first incorporated into polyurethane (P1). Then P1 was swollen in methyl acrylate and photopolymerized to prepare a PMA2.8/PU IPN (P2). Different from photo/force-responsive P1, P2 selectively responded to force because the low free volume in IPN greatly hinders photoisomerization of the rhodamine spirolactam, suggesting that a simple IPN strategy successfully resolves the giant problem of nonselective response to photo/force for photochromic mechanophores. Moreover, PMA/PU IPN enhanced the mechanical property, resulting in a higher mechanochemical activation ratio than PU, and the prestretching effect of PMA/PU IPN promoted the force sensitivity of rhodamine mechanophores significantly. We believe that the strategy can be applied to other mechanophores, promoting their application in more complicated environments.

Multifunctional, Degradable Wearable Sensors Prepared with an Initiator and Crosslinker-Free Method.

The present zwitterionic hydrogel-based wearable sensor exhibits various limitations, such as limited degradation capacity, unavoidable toxicity resulting from initiators, and poor mechanical properties that cannot satisfy practical demands. Herein, we present an initiator and crosslinker-free approach to prepare polyethylene glycol (PEG)@poly[2-(methacryloyloxy)ethyl] dimethyl-(3-sulfopropyl) (PSBMA) interpenetrating polymer network (IPN) hydrogels that are self-polymerized via sunlight-induced and non-covalent crosslinking through electrostatic interaction and hydrogen bonding among polymer chains. The PEG@PSBMA IPN hydrogel possesses tissue-like softness, superior stretchability (∼2344.6% elongation), enhanced fracture strength (∼39.5 kPa), excellent biocompatibility, antibacterial property, reliable adhesion, and ionic conductivity. Furthermore, the sensor based on the IPN hydrogel demonstrates good sensitivity and cyclic stability, enabling effective real-time monitoring of human body activities. Moreover, it is worth noting that the excellent degradability in the saline solution within 8 h makes the prepared hydrogel-based wearable sensor free from the electronic device contamination. We believe that the proposed strategy for preparing physical zwitterionic hydrogels will pave the way for fabricating eco-friendly wearable devices.

Enhancing Chronic Wound Healing through Engineering Mg2+-Coordinated Asiatic Acid/Bacterial Cellulose Hybrid Hydrogels.

Infectious chronic wounds have gradually become a major clinical problem due to their high prevalence and poor treatment outcomes. The urgent need for wound dressings with immune modulatory, antibacterial, and angiogenic properties has led to the development of innovative solutions. Asiatic acid (AA), derived from herbs, has demonstrated excellent antibacterial, anti-inflammatory, and angiogenic effects, making it a promising candidate for incorporation into hydrogel carriers for wound healing. However, there is currently no available report on AA-based self-assembled hydrogels. Here, a novel hybrid hydrogel dressing consists of interpenetrating polymer networks composed of self-assembled magnesium ion (Mg2+) coordinated asiatic acid (AA-Mg) and bacterial cellulose (BC) is developed to promote infected chronic wound healing. A natural carrier-free self-assembled AA-Mg hydrogel with good injectable and self-healing properties could maintain the sustained release of AA and Mg2+ over an extended period. Notably, the introduction of Mg2+ boosted some pharmacological effects of self-assembled hydrogels due to its excellent anti-inflammatory and angiogenesis. In vitro studies confirmed the exceptional biocompatibility, antibacterial efficacy, and anti-inflammatory potential of the AA-Mg/BC hybrid hydrogel, which also exhibited a commendable mechanical strength. Furthermore, in vivo biological results displayed that the hybrid hydrogel significantly accelerated the wound healing process by boosting dense and organized collagen deposition and the granulation tissue and benefiting revascularization. The introduced self-assembled AA-Mg-based hydrogel offers a promising solution for the effective management of chronic wounds. This universal strategy for the preparation of self-assembled hydrogels modulated with bioactive divalent metal ions is able to excavate more herbal small molecules to construct new self-assembled biomaterials.

Hierarchical porous carbon guided by constructing organic-inorganic interpenetrating polymer networks to facilitate performance of zinc hybrid supercapacitors

Customized design of well-defined cathode structures with abundant adsorption sites and rapid diffusion dynamics, holds great promise in filling capacity gap of carbonaceous cathodes towards high-performance Zn-ion hybrid supercapacitors (ZHC). Herein, we fabricate a series of dynamics-oriented hierarchical porous carbons derived from the unique organic-inorganic interpenetrating polymer networks. The interpenetrating polymer networks are obtained through physically knitting polyferric chloride (PFC) network into the highly crosslinked resorcinol-formaldehyde (RF) network. Instead of covalent bonding, physical interpenetrating force in such RF-PFC networks efficiently relieves the RF skeleton shrinkage upon pyrolysis. Meanwhile, the in-situ PFC network sacrifices as a structure-directing agent to suppress the macrophase separation, and correspondingly 3D hierarchical porous structure with plentiful ion-diffusion channels (pore volume of 1.35 cm3/g) is generated in the representative HPC4via nanospace occupation and swelling effect. Further removal of Fe fillers leaves behind a large accessible specific surface area of 1550 m2/g for enhanced Zn-ion adsorption. When used as the cathode for ZHC, HPC4 demonstrates a remarkable electrochemical performance with a specific capacity of 215.1 mAh/g at 0.5 A/g and a high Zn2+ ion diffusion coefficient of 11.1 × 10−18 cm2/s. The ZHC device yields 117.0 Wh/kg energy output at a power density of 272.1 W/kg, coupled with good cycle lifespan (100,000 cycles@10 A/g). This work inspires innovative insights to accelerate Zn diffusion dynamics by structure elaboration towards high-capacity cathode materials.

Effect of epoxy value on the rheological properties and microcosmic mechanism of WER emulsified asphalt.

Waterborne epoxy resin (WER), a cleaning material with exceptional high-temperature resistance, has attracted much attention to modify emulsified asphalt in the pavement material field. Epoxy value is the critical characteristic index of WER. In this research, three WER with the epoxy values of 0.20 eq/100g, 0.44 eq/100g, and 0.51 eq/100g were utilized as asphalt modifiers. The influence of epoxy value on WER-EA was investigated by comparing the rheological properties of three kinds of WER emulsified asphalt (WER-EA). The modification mechanism of WER-EA has been analyzed using FTIR and SEM. The results demonstrate that different WER-EA resulted in significantly different rheological properties. WER-EA with the epoxy value of 0.20 eq/100g (E20) performed best at high temperatures, with a maximum increase of 17477% in G*/sinδ compared to the neat asphalt and a maximum increase of 66.3% in G*/sinδ compared to the other two WER-EA. WER-EA with 0.44 eq/100g epoxy value (E44) performed best at low temperatures, with a maximum increase in m value of 39.4% and a maximum decrease in S value of 33.3% compared to the other two WER-EA. In addition, the interpenetrating polymer network (IPN) in E20 was observed to be more solid and stable, and IPN in E44 was more uniform. To summarize, lower epoxy value led to a higher degree of WER reaction and higher content of rigid groups, which is more conducive to optimizing the high-temperature property of WER-EA. WER with moderate epoxy value resulted in a low content of polar bonds and thus high content of flexible segments, which helps emulsified asphalt to form a more uniform IPN.

Formulation and Characterization of Interpenetrating Polymer Network Hydrogel Bead as Drug Carrier System for Extended Release of Sulphonyl Urea Medication

Formulation and Characterization of Interpenetrating Polymer Network Hydrogel Bead as Drug Carrier System for Extended Release of Sulphonyl Urea Medication

Icephobic Coating Based on Epoxy/Polydimethylsiloxane Interpenetrating Polymer Network Gel

Ice accretion endangers the safety and reliability of equipment operation in frigid regions. Silicone polymer icephobic coatings present themselves as an effective strategy. However, they face durability challenges, which is a crucial foundation for expanding their application. In this work, a durable icephobic coating was prepared based on an epoxy/polydimethylsiloxane (PDMS) interpenetrating polymer network (IPN) gel. In the process, epoxy was used to improve mechanical performance. IPN technology was used to integrate PDMS and epoxy. Low-molecular-weight silicone oil was used to adjust the elastic modulus of the coating by reducing crosslinking. The mechanical properties, icephobicity and durability of the coatings were characterized through elastic modulus measurements, ice adhesion strength tests, and icing/deicing cycle tests, respectively. Results shows the ice adhesion strength of the epoxy/PDMS IPN gel coating was approximately 8 kPa when the elastic modulus was 0.18 MPa. Additionally, the epoxy/PDMS IPN gel has good durability, weather resistance, and substrate adhesion. After 25 icing/deicing cycle tests, the coating remained undamaged, and the ice adhesion strength was stable in the range of 3–14 kPa. Within the range of −5 to −30 °C, the ice adhesion strength of the coating was stable and less than 20 kPa. After 168 h of salt spray aging test, the ice adhesion strength of the coating was maintained at 48.72 ± 5.27 kPa. This can provide a reference for an icephobic coating design.

Photocatalytic driven ‘self-cleaning’ IPN membranes infused with a ‘host-guest’ pair consisting of metal-organic framework encapsulated anionic ‘nano-clusters’ for water remediation

Traditional water treatment membranes frequently encounter challenges in attaining an ideal equilibrium between permeability and selectivity. The performance of membranes is further hampered by hydrophobicity, scalability, and fouling problems, as well as excessive energy consumption. Hence, the current research is dedicated to the development of highly effective antifouling membranes, aiming for a significant balance between water permeance and separation efficiency, and featuring exceptional photocatalytic self-cleaning properties to ensure the sustainable reuse of membranes. In this study, a unique nanocomposite-based membrane is designed containing metal-organic frameworks (MOFs) MIL-101 (Fe) encapsulated copper-containing polyoxometalate (Cu-POM) incorporated into an interpenetrating polymer networks (IPNs) membrane. POMs are highly electronegative, oxo-enriched nanosized metal-oxygen cluster species and when composited with MOF yields POMOF which can help in the removal of pollutants from water through electrostatic site-specific binding. The IPN membrane designed by polymerizing aniline in the presence of polyvinylidene fluoride (PVDF) offers tunable pores of the membrane. The infusion of POMOF imparts a strong negative charge to the membrane surface, improving membrane hydrophilicity. This enhances pollutant removal through the Donnan exclusion principle and adds anti-fouling properties. Furthermore, the reduced pore size achieved by the IPN architecture in the POMOF@IPNs membrane effectively sieves out both cationic and anionic dyes, as well as pharmaceutical pollutants. Additionally, POMOF enhances the photocatalytic degradation of CR and MB dyes, coupled with essential self-cleaning attributes vital for separation processes. The IPNs structure, apart from housing POMOF, fortifies the membrane's mechanical strength with its distinctive network-like configuration. Furthermore, these advanced membranes showcase robust antibacterial and antiviral characteristics, while remaining non-cytotoxic to mammalian cells. Our findings indicate that the state-of-the-art POMOF@IPNs membrane is scalable and holds substantial promise for industrial wastewater treatment.

'Donor-acceptor', 'interpenetrating polymer network' and 'electrostatic self-assembly' work in tandem to achieve extraordinary specific shielding effectiveness.

The exploration of 'electrostatic self-assembly' on solid surfaces has garnered significant interest across various fields. With the sophistication of gadgets, managing electromagnetic interference (EMI) from stray signals, especially in stealth applications, necessitates materials that can absorb microwaves. A promising approach involves integrating lightweight self-healing polymeric materials. This study employs electrostatic self-assembly to design a carbon nanotube structure on an interpenetrating polymer network (IPN) made of PVDF and bismaleimide (BMI)-grafted dopamine hydrochloride, enhancing mechanical integrity through well-formed IPNs. Graphene oxide (GO) is introduced before IPN formation to facilitate an 'acceptor-donor' interaction via the Diels-Alder adduct between BMI and GO, which binds with multi-walled carbon nanotubes (MWCNTs). MWCNTs, modified with PQ7 or PDDA for a positive charge, self-assemble onto the IPN-GO construct, creating a lightweight and chemically stable structure capable of absorbing electromagnetic radiation. The 21 μm thick construct exhibits enhanced microwave absorption within the X-band (8.2-12.4 GHz), with a specific shielding effectiveness of 8637 dB cm2 g-1 and a green index (gs ≈ 1.41). The construct is coated with self-healable polyetherimide (PEI) containing exchangeable disulfide bonds to address maintenance challenges, providing heat-triggered self-healing properties. These innovative structures offer solutions for 5G and IoT applications where lightweight, durable, and multifunctional properties are essential for effectively shielding electronic devices from stray signals.

Thermoresponsive oil-continuous gels based on double-interpenetrating colloidal-particle networks.

Gels composed of multicomponent building blocks offer promising opportunities for the development of novel soft materials with unique and useful structures. While interpenetrating polymer networks have been extensively studied and applied in the creation of these gels, equivalent strategies utilizing colloidal particles have received limited scientific and technological attention. This study presents a novel class of thermo-responsive apolar double gels from interpenetrating networks of attractive colloidal silica and lipid particles. These double gels are easily assembled and suitable for the fabrication of 3D-printed edible soft constructs. Emphasis is focused on the rheological properties and structure emerging on the dilute regime (ϕ ≲ 0.1). Rheological investigations demonstrate that double gels exhibit greater stiffness and resilience to yielding compared to their single lipid gel counterparts. The scaling behavior of the oscillatory linear shear moduli and the critical strain for yielding with volume fraction remain comparable between single and double gels. Creep yielding in double gels exhibits two exponential decay regimes, suggesting the presence of thicker gel strands undergoing flow. Visualization and quantification of the quiescent microstructure confirms the existence of such denser aggregates devoid of larger clusters due to steric hindrance of interpenetrating networks in double gels. This is in stark contrast to lipid single gels where aggregates grow unrestrictedly into larger clusters. Our study constitutes the first demonstration on the assembly of apolar double gel networks as a promising avenue for the design of novel soft materials and foods with tailored structure and mechanics.

The biological applications of IPN hydrogels.

Interpenetrating polymer network (IPN) hydrogels are an adaptable category of materials, exhibiting remarkable promise for various biological applications due to their distinctive structural and functional attributes. This review delves into the synthesis of IPN hydrogels through both physical and chemical methodologies, elucidating how these techniques allow for precise tailoring of mechanical properties, swelling behaviour, and biocompatibility. We conducted an extensive literature review by searching well-established online research databases for articles published since 2009 to gather comprehensive data on IPN hydrogels. Our review highlights several critical applications of IPN hydrogels in the biomedical field; i) Tissue engineering: IPN hydrogels are evaluated for their capacity to emulate the extracellular matrix, making them excellent scaffolds for tissue engineering; ii) Controlled drug release: The ability of IPN hydrogels to modulate drug release rates and protect bioactive molecules is explored. Their structure enables sustained and targeted delivery of therapeutic agents, enhancing treatment efficacy; iii) 3D bioprinting: The use of IPN hydrogels as bioinks for 3D bioprinting is assessed, demonstrating their capability to construct intricate, biomimetic structures with high precision; and iv) Regenerative medicine: the development of biomimetic IPN hydrogels for regenerative medicine, emphasizing their potential to closely replicate natural biological environments, thereby promoting effective tissue repair and regeneration. IPN hydrogels emerge as a versatile and multifaceted platform with significant implications for advancing biomedical science and clinical therapies. Their diverse applications highlight their potential to revolutionize current biomedical practices and contribute to the development of innovative therapeutic solutions.

Multiple hydrogen bonding driven supramolecular architectures and their biomedical applications.

Supramolecular chemistry combines the strength of molecular assembly via various molecular interactions. Hydrogen bonding facilitated self-assembly with the advantages of directionality, specificity, reversibility, and strength is a promising approach for constructing advanced supramolecules. There are still some challenges in hydrogen bonding based supramolecular polymers, such as complexity originating from tautomerism of the molecular building modules, the assembly process, and structure versatility of building blocks. In this review, examples are selected to give insights into multiple hydrogen bonding driven emerging supramolecular architectures. We focus on chiral supramolecular assemblies, multiple hydrogen bonding modules as stimuli responsive sources, interpenetrating polymer networks, multiple hydrogen bonding assisted organic frameworks, supramolecular adhesives, energy dissipators, and quantitative analysis of nano-adhesion. The applications in biomedical materials are focused with detailed examples including drug design evolution for myotonic dystrophy, molecular assembly for advanced drug delivery, an indicator displacement strategy for DNA detection, tissue engineering, and self-assembly complexes as gene delivery vectors for gene transfection. In addition, insights into the current challenges and future perspectives of this field to propel the development of multiple hydrogen bonding facilitated supramolecular materials are proposed.

Anisotropically self-oscillating gels by spatially patterned interpenetrating polymer network.

Here we introduce sub-millimeter self-oscillating gels that undergo the Belousov-Zhabotinsky (BZ) reaction and can anisotropically oscillate like cardiomyocytes. The anisotropically self-oscillating gels in this study were realized by spatially patterning an acrylic acid-based interpenetrating network (AA-IPN). We found that the patterned AA-IPN regions, locally introduced at both ends of the gels through UV photolithography, can constrain the horizontal gel shape deformation during the BZ reaction. In other words, the two AA-IPN regions could act as a physical barrier to prevent isotropic deformation. Furthermore, we controlled the anisotropic deformation behavior during the BZ reaction by varying the concentration of acrylic acid used in the patterning process of the AA-IPN. As a result, a specific directional deformation behavior (66% horizontal/vertical amplitude ratio) was fulfilled, similar to that of cardiomyocytes. Our study can provide a promising insight to fabricating robust gel systems for cardiomyocyte modeling or designing novel autonomous microscale soft actuators.

Functionalized hexagonal boron nitride sheets and charge triggered interpenetrating polymer network based membranes work in tandem towards water remediation

Charge triggered membranes demonstrate excellent resistance to fouling and high rejection rates towards charged dyes.