A series of physical double-network hydrogels is synthesized based on an amphiphilic triblock copolymer. The gel, which contains strong hydrophobic domains and sacrificial dynamic bonds of hydrogen bonds, is stiff and tough, and even stiffens in concentrated saline solution. Furthermore, due to its supramolecular structure, the gel features improved self-healing and self-recovery abilities

Background The prevalence of hypertension is high and increasing worldwide while the proportion of controlled hypertension is low. Purpose To assess the comparative effectiveness of 8 implementation strategies for blood pressure (BP) control in adults with hypertension. Data Sources Systematic searches of MEDLINE and Embase from inception to September 2017 with no language restriction supplemented with manual reference searches. Study Selection Randomized controlled trials lasting at least 6 months comparing implementation strategies versus usual care on BP reduction in adults with hypertension. Data Extraction Two investigators independently extracted trial data. Trials were grouped by implementation strategy, and BP reduction effects were compared using multivariate-adjusted generalized estimating equations. A modified Cochrane Risk of Bias tool was used for trial quality assessment. Data Synthesis A total of 121 comparisons from 100 articles with 55,920 hypertensive patients were included. Multilevel, multicomponent strategies, such as team-based care with medication titration by non-physician [−7.1 mmHg (95% CI: −8.9, −5.2)], team-based care with medication titration by physician [−6.2 mmHg (−8.1, −4.2)], and multilevel strategies without team-based care [−5.0 mmHg (−8.0, −2.0)] were most effective for systolic BP reduction. Patient-level strategies also resulted in significant systolic BP reductions of −3.9 mmHg (−5.4, −2.3) for health coaching and −2.7 mmHg (−3.6, −1.7) for home BP monitoring. Similar trends were observed for diastolic BP reduction. Provider training was tested in few trials and resulted in non-significant BP reduction. Limitations Sparse data from low- and middle-income countries, few trials of some implementation strategies, and possible publication bias. Conclusions Multilevel, multicomponent strategies, followed by patient-level strategies, are most effective for BP control in patients with hypertension and ought to be used to improve hypertension control. Primary Funding Source US National Institutes of Health

Tough and self-recoverable hydrogel membranes with micrometer-scale thickness are promising for biomedical applications, which, however, rarely be realized due to the intrinsic brittleness of hydrogels. In this work, for the first time, by combing noncovalent DN strategy and spin-coating method, we successfully fabricated thin (thickness: 5-100 µm), yet tough (work of extension at fracture: 10 5 -10 7 J m −3 ) and 100% self-recoverable hydrogel membranes with high water content (62-97 wt%) in large size (≈100 cm 2 ). Amphiphilic triblock copolymers, which form physical gels by self-assembly, were used for the first network. Linear polymers that physically associate with the hydrophilic midblocks of the first network, were chosen for the second network. The internetwork associations serve as reversible sacrificial bonds that impart toughness and self-recovery properties on the hydrogel membranes. The excellent mechanical properties of these obtained tough and thin gel membranes are comparable, or even superior to many biological membranes. The in vitro and in vivo tests show that these hydrogel membranes are biocompatible, and postoperative nonadhesive to neighboring organs. The excellent mechanical and biocompatible properties make these thin hydrogel membranes potentially suitable for use as biological or postoperative antiadhesive membranes.

Recently, many tough and self-healing hydrogels have been developed based on physical bonds as reversible sacrificial bonds. As breaking and reforming of physical bonds are time-dependent, these hydrogels are viscoelastic and the deformation rate and temperature pronouncedly influence their fracture behavior. Using a polyampholyte hydrogel as a model system, we observed that the time-temperature superposition principle is obeyed not only for the small strain rheology, but also for the large strain 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59

Hydrogels derived from lignin are typically weak and contain only a small amount of lignin, which limits their broad application prospects. In the present work, a novel lignin/poly­(N,N-dimethylacrylamide) (PDMA) hydrogel with a high lignin content, superb toughness, and ultrahigh antioxidative performance is constructed by employing a facile dissolve–dry–swell solvent exchange method. Through this process, lignin and PDMA are self-assembled into a multienergy dissipative structure containing rigid lignin-rich domains. Precisely, the PDMA chains both interpenetrated inside and adhered on the surface of these domains through hydrophobic associations. This structure enables the lignin hydrogels to dissipate energy efficiently during the fracture process. At an optimized ultrahigh lignin content of 58% (dry weight basis), the prepared lignin hydrogel exhibited remarkable mechanical properties, such as a high elastic modulus (2.5 MPa), tensile strength (2.5 MPa), and super tensile strain (11.3), and an extremely high fracture energy above 16 000 J m–2. In addition, the tough lignin hydrogel exhibited a commendable antioxidant property and nontoxicity. All these advantageous properties provide the lignin/PDMA hydrogels with the potential for use in biomedical materials applications.

introduced ion-rich pores into a strong hydrogel matrix to realize the hydrogel with high ionic conductivity of 3.4 S m −1 and large tensile stress of 1.3 MPa. [2] However, the introduction of ion-rich pores largely decreased the mechanical strength of the strong hydrogel matrix. The increase of ionic conductivity, as well as the mechanical strength, was still a challenge. Furthermore, most of the ionic conductive hydrogels contained synthetic polymers which would increase the environmental burden.Gelatin is a wildly existing biomass material with high environmental friendliness and excellent biodegradability. Tough gelatin hydrogel was obtained by simply soaking pure gelatin hydrogel in ammonium sulfate (AS) solution due to the saltout effect. [7] Based on this study, herein, we utilized the selfaggregation of gelatin caused by the salt-out effect in concentrated AS solution to create chain-dense and ion-rich regions, realized the increase of mechanical strength and ionic conductivity simultaneously, and conducted a gelatin hydrogel with high mechanical strength, toughness, and ionic conductivity by a simple soaking-heating method.The preparation process is shown in Scheme 1. By cooling the 10 wt% gelatin solution, gelatin hydrogel crosslinked by the helix junctions is formed. The gelatin gel was soaked in 30 wt% AS solution. The restricted aggregation of gelatin chains, caused by constraint from crosslinks and the salt-out effect, reinforced physical interactions between gelatin chains and resulted in the dense and ductile gelatin/AS gel (Gel/AS gel). [7] Subsequently, the Gel/AS gel was directly heated in the AS solution at 42 °C for n min and then cooled to room temperature immediately to prepare the final heated gelatin/ AS gels. The heated gels were coded as Hn-Gel/AS gels for simple, where n stood for the heating time by minutes. As the heating time increased, the gel shrank slightly ( Figure S1, Supporting Information) and turned white gradually ( Figure S2, Supporting Information; Scheme 1) indicating the phase separation at a relatively large size scale. The scanning electron microscope (SEM) measurement was also performed to observe the structure change of the Gel/AS gel after heating. As shown in Figure 1, after being heated for 1 min (Figure 1b), dense regions with increased density of large pores were observed. However, after being heated for 5 min the gel structure became very dense with almost no pores (Figure 1c). This was considered as a combined result of heating and the salt-out effect. The helical junctions in the Gel/AS gel were gradually destroyed by heating, and the constraint to the gelatin chains was reduced. The less constrained gelatin chains in the AS solution would fold and aggregate to form larger chain-dense regions due to the "salt-out" effect. The increase of the chain Hydrogels for electronic applications require stretchability, high electrical conductivity, and high mechanical strength. A mechanically robust ionic conductive gelatin hydrogel is constructed by a simple soaking-...

Flexible energy storage materials and sensors have become the key equipment of human–machine interface technology. For the preparation of these devices, hydrogel electrodes are relevant because of their unique porous structure, high capacitance, flexibility, small size, and lightweight. In this paper, regular polypyrrole (PPy) is synthesized on a heat-induced phase-separated gel (H-Gel/AS) by the template degradation method, and a gelatin-based PPy hydrogel with high strength, high strain rate, and high conductivity is prepared. Moreover, by adding multiwalled carbon nanotubes (MWCNTs) into a gelatin solution according to the H-Gel/AS method, the electrochemical performance of the resulting H-Gel/AS-MWCNTs-PPy electrode is greatly improved. When the H-Gel/AS-MWCNTs-PPy gel is immersed in an ammonium sulfate solution, wrinkles appear on the surface, resulting in further enhancement of the capacitance. On this basis, a flexible sensor and a solid-state supercapacitor are assembled, and their performance is tested. The sensor can detect tensile, bending, and twisting strains with high sensitivity. Meanwhile, as a flexible solid-state supercapacitor, the specific capacitance is 75 F g–1, and the capacitance retention rate after 5000 cycles is 98.1% under bending conditions. More importantly, the gelatin-based hydrogel shows great potential for application in wearable devices.

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