聚丙烯酰胺/碳量子点/氧化石墨烯复合水凝胶制备及其性能分析

目前相比于只用一种物理交联剂,同时用两种物理交联剂提高复合水凝胶力学性能的研究少有报道。为了研究同时以碳量子点（CQDs）和氧化石墨烯（GO）作为多官能度物理交联剂对复合水凝胶力学性能的影响,本文首先分别用低温水热法和改进的Hummer法制备了50mg/mL 的CQDs水分散液和5mg/mL的GO水分散液。通过原位自由基聚合的方法,改变CQDs和GO用量,制备了一系列聚丙烯酰胺（PAM）类纳米复合水凝胶（PAM/CQDs/GO）。利用X射线衍射仪、拉力机和流变仪对所得的水凝胶进行表征和测试。得出当用1mL的CQDs水分散液和4mL的GO水分散液制备的PAM/CQDs/GO复合水凝胶力学综合性能最好,其断裂伸长率为3916.86%,拉伸强度为165.3kPa,杨氏模量为33.36kPa。结果表明：适量的CQDs和GO都能提高PAM/CQDs/GO复合水凝胶的多种力学性能,其中GO更有利于增大纳米复合水凝胶的拉伸强度、杨氏模量和耗散能,而CQDs更有利于增大断裂伸长率。与GO相反,CQDs的加入能提高纳米复合水凝胶的黏性、降低其刚性和再次被拉伸时的杨氏模量。通过对CQDs和GO的用量进行调节,可以制备出力学性能不同的纳米复合水凝胶,以满足不同领域的需要,拓宽水凝胶的应用范围。     

Property modulation of poly(N‐isopropylacrylamide) hydrogels by incorporation of modified silica

Poly(N‐isopropylacrylamide) (PNIPA)/silica composite hydrogels were prepared and the effects of the silica incorporation on the swelling and breaking characteristics of the hydrogels were investigated. To improve the dispersive property of silica in the PNIPA matrix via the formation of covalent bonds between the polymer and silica, vinyl groups were introduced in the silica by reacting it with a coupling agent, 3‐methacryloxypropyltrimethoxysilane. When unmodified silica was used as filler in the PNIPA‐composite hydrogel, the swelling ratio of the composite hydrogel below the critical gel transition temperature (CGTT) increased with increasing silica content. However, when the modified silica was used as the filler, the swelling ratio below CGTT decreased with increasing silica content because of the enhanced distribution and additional crosslinking. Above CGTT, the swelling ratios of the PNIPA/silica hydrogels were similar regardless of the silica modification. The gel breaking stress of the hydrogels increased with increasing silica content, and this enhancement was larger for the modified silica hydrogel. Scanning electron microscopy images showed that the modified silica particles were distributed more evenly in the PNIPA matrix than the unmodified ones were and that the size of cell‐like structure of the hydrogel decreased with increasing modified silica content. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

聚丙烯酸/氧化石墨烯复合水凝胶制备及对亚甲基蓝吸附

以丙烯酸(AA)为原料,二丙烯酸酯(Pul DA)分散的氧化石墨烯(GO)纳米胶粒(GO-Pul DA)为增强剂,N,N'-亚甲基双丙烯酰胺(BIS)为交联剂,通过自由基共聚合制备了一系列结构均一的聚丙烯酸/氧化石墨烯复合水凝胶(PAA/GO-Pul DA)。考察了BIS质量浓度、GO质量浓度以及溶液pH值对复合水凝胶力学性能、吸水性和亚甲基蓝(MB)吸附量的影响。结果表明,当GO质量浓度从0.1 g/L增加至1.0 g/L时,复合水凝胶拉伸强度从5.0 k Pa增加至10.4 k Pa,断裂伸长率高于100%,当GO的质量浓度为0.3 g/L时,复合水凝胶的断裂伸长率最高为151%;复合水凝胶表现出pH敏感的高吸湿性,pH从3.0增加至6.8时,平衡溶胀比(SRe)变化可达386 g/g,pH=6.8时最大SRe高达490 g/g。当溶液pH值从3.0增加至11.0时,PAA/GO-Pul D对MB的平衡吸附量(qe)可增加1 400~1 500 mg/g,pH=11.0时最大的qe高达1 789 mg/g。复合水凝胶对MB的吸附行为符合准一级动力学模型。5次吸附-解吸附循环后,相对于首次吸附,PAA/GO-Pul D对MB的吸附能力仍保持高达60%,解吸附效率高于90%。     

Star‐shaped polycaprolactone/chitosan composite hydrogels: fabrication and characterization

Star‐shaped polycaprolactone (stPCL)/chitosan composite hydrogel was fabricated by simply melt/solution blending between chitosan/dicarboxylic acid solution and melted stPCL, using 1‐(3‐dimethylaminopropyl)‐3‐ethylcarbodiimide hydrochloride and N‐hydroxysuccinimide as conjugating agents to obtain a composite hydrogel. Here, stPCL and modified stPCL were investigated. The stPCL was modified to have a carboxyl‐terminated chain (stPCL‐COOH). The composite hydrogels were transparent. The network structure of the composite hydrogels was investigated. stPCL‐OH had no chemical bond to the chitosan network but stPCL‐COOH could co‐crosslink with the chitosan network. The porous structure and porosity of the composite hydrogels were similar to those of chitosan hydrogel. However, the hydrophobicity of stPCL resulted in a lower swelling ratio compared to chitosan hydrogel. The rheological analysis of the composite hydrogel exhibited a stable crosslinked network. Compression testing of the composite hydrogel obtained from stPCL‐COOH at a mole ratio of stPCL‐COOH and chitosan of 1:1 had optimum compressive mechanical properties comparable to chitosan hydrogel due to a synergistic effect of the flexibility in stPCL and the co‐crosslinking of stPCL‐COOH with the chitosan network. © 2020 Society of Chemical Industry     

Hydrogen bonding induced enhancement for constructing anisotropic sugarcane composite hydrogels

Anisotropic hydrogels are appealing with their merits of similar biochemical and structural properties to the biological tissues. However, the mechanical properties of current anisotropic hydrogels need to be further improved. Herein, three kinds of novel anisotropic poly(2-hydroxyethyl methacrylate) (pHEMA), poly(acrylamide) (pAM), and poly(acrylamide-co-acrylic acid) (p[AM-co-AA]) sugarcane composite hydrogels were prepared successfully by filling the hydrogel monomer precursor into porous aligned sugarcane nanofibers network and then performing subsequent free radical polymerization. The hydrogel matrix and sugarcane nanofibers network were combined closely together through hydrogen bonding interaction. The anisotropic sugarcane composite hydrogels exhibit good flexibility and elastic recovery properties upon encountering mechanical crimping and twisting. In typical case, the as-prepared pHEMA sugarcane composite hydrogel can exhibit high anisotropic tensile strength of 2.37 and 0.54 MPa, while differential tear strength of 0.36 and 0.78 N/mm, along the parallel and vertical nanofibers directions. Finally, anisotropic lubrication behaviors were found and investigated systematically for those three kinds of sugarcane composite hydrogels when water was used as lubricant. Our current work proposes a simple and universal strategy for developing bioinspired anisotropic functional composite matters such as artificial skin, flexible sensor, and cartilage lubrication materials.     

Imparting antifouling properties of silicone hydrogels by grafting poly(ethylene glycol) methyl ether acrylate initiated by UV light

Both hydrophilic and antifouling surfaces were prepared on silicone hydrogels with poly(ethylene glycol) methyl ether acrylate (PEGMA) grafted by UV-induced radical polymerization. The PEGMA-grafted silicone hydrogels were characterized by graft yield and static water contact angle measurements. According to the results, the graft yield reached a maximum at 8 min of UV exposure time and 20 wt% PEGMA concentration. The modified silicone hydrogels possessed hydrophilic surfaces with the lowest water contact angle of 36°. The oxygen permeability and transparency of the PEGMA-grafted silicone hydrogels were as high as the unmodified silicone hydrogel. The mechanical property of silicone hydrogels was maintained at about 95% of the tensile strength and elastic modulus after the PEGMA grafting. The in vitro single protein adsorption on the PEGMA-grafted silicone hydrogels decreased by 70–80% compared to the unmodified silicone hydrogel. The PEGMA-grafted silicone hydrogel is expected to be a novel biomaterial, which possesses excellent surface hydrophilicity, antifouling property, oxygen permeability, and mechanical property. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Fabrication of alginate/sericin/cellulose nanocrystals interpenetrating network composite hydrogels with enhanced physicochemical properties and biological activity

Sodium alginate (SA) possesses good biocompatibility and can form hydrogel materials under certain conditions, which has been widely used in tissue engineering. However, the absence of cellular recognition sites and low mechanical strength for single-component alginate (ALG) hydrogels limit their practical applications. Therefore, enhancing the shortcomings of ALG hydrogels and augmenting their characteristics hold immense importance for their medical uses. In this study, comprehensively considering the excellent properties of cellulose nanocrystals (CNCs) and sericin (SS), the alginate/sericin/cellulose nanocrystalline (ALG/SS/CNCS) composite hydrogels were constructed by interpenetrating network (IPN) technique using hydroxyapatite/D-glucono-δ-lactone (HAP/GDL) as the endogenous ionic cross-linking agent of SA, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) as the chemical covalent cross-linking agent of SS and CNCS as the reinforcing agent. The effects of SS and CNCs additions on the comprehensive properties of ALG/SS/CNCs composite hydrogels, such as their morphologies, structure, mechanical properties, swelling, degradability, and cytocompatibility were investigated. The findings indicated that the ALG/SS/CNCS IPN composite hydrogels which were created through the physical blending of SA and SS, displayed a consistent three-dimensional form and a porous configuration. The weak mechanical strength of pure ALG hydrogels can be effectively improved and the swelling stability and mechanical properties of the composite hydrogels can be enhanced through the construction of IPN network and the incorporation of CNCs, thanks to the presence of intermolecular hydrogen bonding. The biodegradability of ALG/SS/CNCS composite hydrogels increased as the SS content increased, indicating that SS facilitated their biomineralization due to its inherent susceptibility to degradation. The results of the cell compatibility test conducted in a laboratory setting showed that SS and CNCS had the ability to enhance the attachment, proliferation, and differentiation of MC3T3-E1 cells on the ALG/SS/CNCS composite hydrogels. Hence, incorporating SS and CNCS into the alginate matrix to create IPN composite hydrogels could significantly enhance the physicochemical and biological characteristics of ALG hydrogels, thus rendering them appropriate for tissue engineering purposes.     

Conductive double-network hydrogel for a highly conductive anti-fatigue flexible sensor

Improving the mechanical properties of hydrogels is a prime example of their large-scale, diverse applications. Herein, we report a one-pot method for preparing a double network system hydrogel where the polyvinyl alcohol served as the first polymer backbone, acrylamide as the second network, and N, N′-Methylenebisacrylamide as the cross-linker, and the prepared hydrogels presented excellent mechanical properties with 1168% tensile strain and 598 kPa compressive strength. Through the metal–ligand bonds, an electrolyte solution containing Cu²⁺ was introduced into the hydrogel, which exhibits higher water retention than other electrolyte-containing hydrogels. Specially, the hydrogel was able to retain water for 8 h under extreme dry conditions at 60°C. The GF value was calculated to be 0.124 when the strain was 0%–64.2%. Furthermore, the hydrogel flexible sensor can detect changes in ambient temperature. When the ambient temperature rises, its relative resistance also tends to rise. In conclusion, this hydrogel sensor offers great potential applications in flexible sensors.     

Improved mechanical and swelling behavior of the composite hydrogels prepared by ionic monomer and acid-activated Laponite

A composite hydrogel (CH) with much improved mechanical and swelling properties was prepared using an ionic monomer and acid-activated Laponite XLS which was used as a cross-linking agent. Addition of acid-activated clay solved the gelation problem when ionic monomers were added to clay mineral dispersions. Reaction of Laponite XLS with sulfuric acid yielded amorphous silica. A dispersion of the acid-activated Laponite and the monomers was used to synthesize composite hydrogels by in-situ polymerization. The FT-IR spectra and rheological results of the composite hydrogels demonstrated the formation of a network. The equilibrium swelling ratios of composite hydrogels (> 6000 g/g) were more than 18 times larger than traditional organic cross-linked hydrogels. The moduli G′ and G″ in the observed frequency range were about 4 and 10 times larger than those of organic cross-linked hydrogel (OR gel). The improvement in both the equilibrium swelling ratio and mechanical strength was attributed to the homogeneous cross-linked network structure.     

类氨基酸基载药水凝胶敷料的制备与性能

为制备一种具有良好生物相容性、可控缓释的物理交联的水凝胶敷料,选用类氨基酸单体N-丙烯酰基甘氨酰胺（NAGA）与生物发酵产物衣康酸（IA）为单体,在紫外光条件下,通过自由基聚合,在不需要外加任何交联剂条件下即可形成水凝胶聚（N-丙烯酰基甘氨酰胺-衣康酸）（P(NAGA-IA)）。所得水凝胶具有溶胶-凝胶转变温度（UCST）、较高的水溶胀率（40倍）及力学性能（压缩模量最高540 kPa）、较优的药物负载性和缓释性,这是因为NAGA单元提供分子间多重氢键作用,进而赋予了水凝胶较优的综合性能;而IA单元赋予了聚合物的pH刺激响应性,从而可诱导药物的释放。因此,所得P (NAGA-IA)水凝胶可作敷料用于创伤治疗。     

Porous boron nitride nanofibers/PVA hydrogels with improved mechanical property and thermal stability

Polyvinyl alcohol (PVA) hydrogel is a promising material possessing good chemical stability, high water absorption, excellent biocompatibility and biological aging resistant. However, the poor mechanical performance of PVA hydrogel limits its applications. Here we report the utilization of one-dimensional (1D) BN nanofibers (BNNFs) as nanofillers into PVA matrix to prepare a novel kind of BNNFs/PVA composite hydrogel via a cyclic freezing and thawing method. For comparison, the composite hydrogels using spherical BN nanoparticles i.e. BN nanospheres (BNNSs) as fillers were also prepared. The mechanical properties, thermal stabilities and swelling behaviors of the composite hydrogels were investigated in detail. Our study indicates that the mechanical properties of the hydrogels can be improved by adding of BNNFs. After loading of BNNFs into PVA with content of 0.5?wt%, the compressive strength of the composite hydrogel increases by 252% compared with that of pure PVA hydrogel. The tensile performance of BNNFs/PVA composite hydrogels has also been improved. Impressive 87.8% increases in tensile strengths can be obtained with 1?wt% BNNFs added. In addition, with the increase of BNNFs content, the thermal stability and the swelling ratio of hydrogels are increased gradually. The swelling ratio of hydrogel increases by 56.3% with only 1?wt% BNNFs added. In comparison, the improvement effects of the BNNS fillers on the mechanical strengths and swelling ratios are much weaker. The enhanced effects of BNNFs can be ascribed to the strong hydrogen bond interaction between BNNFs and PVA. The high aspect ratios of the nanofibers should also be took into account.     

聚环氧乙烷对PAMPS/PAM双网络水凝胶结构和性能的影响

采用紫外光引发聚合制备了含聚环氧乙烷（PEO）的聚(2-丙烯酰胺-2-甲基丙磺酸)(PAMPS）/聚丙烯酰胺（PAM）双网络（DN）水凝胶。使用扫描电子显微镜（SEM）观察了PAMPS单网络水凝胶的结构;测定了PEO改性前后双网络水凝胶的压缩及拉伸性能。PEO改性DN凝胶的第一网络网孔上由于PEO片晶结构引起不同程度的褶皱,这种褶皱起支撑作用;PEO的分子量达到5万时,褶皱的支撑作用最佳,DN凝胶的力学性能最佳;DN凝胶的力学性能随PEO加入量先提高后下降,在PEO加入量为0.1%时,PEO片晶结构加固了DN凝胶的物理交联点,力学性能达到最大,压缩应力达到31.6 MPa;加入更多的PEO阻碍了第一网络的凝胶化,造成网络结构的不连续,从而使DN凝胶的力学性能下降。     

Large strain behaviour of nanostructured polyelectrolyte hydrogels

The mechanical properties of nanostructured polyelectrolyte hydrogels have been investigated targeting specifically the nonlinear deformation regime at large strains and the fracture properties. The hydrogels were synthesized using a thiol-ene cross-linking chemistry of polyacrylic acid precursor chains previously functionalized with double bonds. Some polymers were also grafted with C₁₂ side chains able to form hydrophobic clusters in water. The large strain deformation of these nanostructured gels was tested in uniaxial compression by performing loading/unloading cycles at different strain rates and up to different maximum strains. All hydrogels displayed a pronounced strain hardening before fracture and a strain dependent hysteresis but the magnitude of these effects depended on the details of the composition. The most pronounced strain hardening was observed for the unmodified hydrogels in pure water while the largest hysteresis was found for the gels containing the highest concentration of nanoclusters. These dissipative processes barely influence the mechanical behaviour at small strains where the gel remains very elastic but become important at large strains and improve the resistance to fracture of the gels.     

Nanocomposite carbon dots/PAM fluorescent hydrogels and their mechanical properties

In this work, the bio-friendly fluorescence carbon dots (CDs) which being fabricated by using α-D-lactose as carbon sources were successfully entrapped into the polyacrylamide (PAM) networks by atom transfer radical polymerization (ATRP) method at 50°C, which indicated a simple and versatile approach for a novel CDs/PAM composite hydrogel with both excellent mechanical and fluorescence properties. The HRSEM images exhibited that the CDs/PAM hydrogels have intensive microporous structure and uniformly distributed pores. The tensile and compressive mechanical properties of the CDs/PAM hydrogels with different weight ratios of AM/water (25%~50%)、MBA/AM (0.036%~0.18%) and CDs/water (0.0%~2.0%) were investigated, respectively. The results showed that when the weight ratios of AM/water at 47.6%, MBA/AM at 0.072% and CDs/water at 0.67wt%, the hydrogels exhibited optimized fracture strength at 161.4kPa and fracture stretch at 842.1%. In addition, with increasing weight ratios of the CDs/water from 0.0% to 2.0%, the CDs/PAM composite hydrogels exhibited higher fluorescence intensities and brighter blue fluorescent emission under the UV light excitation (300 nm). The excellent mechanical and fluorescence properties mean that they could be used as potentially optical visualization cartilage replacement materials in biomedical engineering fields.     

等规聚丁烯-1/玉米秸秆复合材料的制备与性能研究

使用硅烷偶联剂γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)改性生物质废弃物玉米秸秆粉(CP),以期改善其与聚合物的相容性,并将其引入等规聚丁烯-1(iPB)基体中制备iPB/CP复合材料,考察了改性前后复合材料的力学性能、热变形温度及微观形貌.结果表明,KH570成功的接枝到CP表面,经过KH570改性后的复合材料...     

Alcohol-triggered silk fibroin hydrogels having random coil and β-turn structures enhanced for cytocompatible cell response

Alcohol additive is one of the stimulants that induces the fast gelation of silk fibroin solution. Based on our previous report, different alcohol types influence the gelation kinetic and the properties of resulting silk fibroin hydrogels. Here, the effects of alcohol concentrations on the silk fibroin gelation and cell response were reported. All fibroin hydrogels prepared with various alcohol additives showed cell biocompatibility, especially the fibroin hydrogel prepared with 10 wt % n-butanol. Results on the mechanical properties of hydrogels, n-butanol additive enhanced a higher compressive modulus up to ~ 22 times in comparison to non-alcoholic fibroin hydrogel. Fourier transform infrared analysis and peak deconvolution showed a possible formation of more β-turn linkage and random coil structure of fibroin segments in alcoholic fibroin hydrogel. So, the micro-segmental structure of fibroin hydrogel caused the higher compressive modulus, prolonged deformation of the hydrogels, and efficient cell growth on the fibroin hydrogel. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48731.     

水溶性Janus型POSS的设计合成及其对PAA/PAM水凝胶力学性能影响的研究

利用丙烯酰氧丙基多面体低聚倍半硅氧烷（Acrylo-POSS）和3-巯基-1-丙烷磺酸盐（MPS）之间的巯基点击反应，一步合成水溶性Janus型多面体低聚倍半硅氧烷（AS-POSS）。通过改变投料比可以调控AS-POSS的水溶性和双键与磺酸钠基团的物质的量比。将AS-POSS与丙烯酸（AA）和丙烯酰胺（AM）共聚制备了一系列不同AS-POSS含量的AS-POSS/PAA/PAM水凝胶，其中AS-POSS质量占单体总质量1%的1% AS-POSS/PAA/PAM水凝胶的平衡溶胀比达到512，断裂伸长率达到1074%，压缩强度为583 kPa，压缩应变为89%，屈服应变为330%，均大于对照组MBA/PAA/PAM水凝胶，表明AS-POSS的引入显著提高了水凝胶的溶胀度，明显增强了水凝胶的韧性、抗压缩性能和动态力学性能。AS-POSS/PAA/PAM水凝胶具有良好的导电性，离子电导率最高可达0.401 S/m。     

Properties of Thermoresponsive N-maleyl gelatin-co-P(N-isopropylacrylamide) hydrogel with ultrahigh mechanical strength and self-recovery

Thermo-responsive polymer hydrogels with superior strength and toughness are potential candidate materials in biomedical field, such as drug delivery system and tissue engineering. By introducing maleylgelatin (MAGEL) into the conventional PNIPAAm hydrogel, a series of composite P(NIPAAm-co-MAGEL) hydrogels with combined features were fabricated. Thermo-responsive behaviors, equilibrium swelling ratio (ESR), compression strength, tensile strength (TS) and elongation at-break (E), cyclic compression tests, and thermal stability properties of hydrogels with different amount of MAGEL were investigated. Experimental data indicated that the amount of MAGEL could modulate the mechanical property of the composite hydrogel. With the increase of the MAGEL contents from 0 to 50%, the composite hydrogel with relatively high water content possessed good compressive strength, tensile strength and stretrability. Only when the weight ratio of MAGEL/NIPAAm was 30:70, did the P(NIPAAm-co-MAGEL) have a homogeneous distribution and stable 3D networks which played a significant role in the properties of the hydrogels. Cyclic compression tests results indicated that P(NIPAAm-co-MAGEL) hydrogel had an excellent thermo-reversible ability. This research would expand the scope of the PNIPAAm hydrogel applications.     

Synthesis and characterization of super‐absorbent hydrogels based on hemicellulose

A kind of novel hemicellulose‐based hydrogel with excellent water absorbency was synthesized by the graft copolymerization of acrylic acid (AA), acrylic amide (AM) with hemicellulose. The various factors that influenced the water absorbency of the modified hemicellulose were studied, including AA content, hemicellulose content, neutralization degree of AA, and weight ratio (to monomer) of cross‐linker and initiator. The optimal conditions were found as follows: m(AA) : m(AM) : m(hemicellulose) = 15 : 3.5 : 1, the neutralization degree of AA was 75%, and weight ratio (to monomers) of the cross‐linker and the initiator was 0.03% and 1.0%, respectively. The maximum absorbencies toward distilled water and 0.9 wt % NaCl solution were 1128 g/g and 132 g/g, respectively. The characteristics of the hydrogels were also investigated by Fourier Transform InfraRed (FT‐IR), scanning electron microscope (SEM), and atomic force microscope (AFM). The results indicated that the undulant surface and broad network structure offer the hydrogels excellent water absorbency. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42441.     

High strength and toughness of double physically cross-linked hydrogels composed of polyvinyl alcohol and calcium alginate

The weak mechanical properties of hydrogels, especially physically cross-linked hydrogels are usually a major factor to hinder their application. To solve this problem, in this work, we prepared a high strength and toughness of double physically cross-linked (PDN) hydrogels composed of crystalline domain cross-linked polyvinyl alcohol (PVA) and Ca²⁺-cross-linked alginate (Alg). With a further annealing treatment, the noncovalent cross-linked network via the formed crystalline promote the as-prepared PDN PVA/Alg hydrogel to exhibit well mechanical properties with the tensile strength of ~1.94 MPa, elongation at break of ~607% and Young's modulus of ~0.45 MPa (above 70 wt% of water content). By analyzing the mechanism of improving the hydrogel mechanical properties, it is found that annealing can effectively improve the crystallinity of PVA in the hydrogel, and then greatly improve the mechanical properties of the hydrogel. This provides a general method for improving the mechanical properties of PVA PDN hydrogels. In addition, the PDN PVA/Alg hydrogel was also proved to have good ionic conductivity of 1.70 S m⁻¹. These desirable properties make the prepared physically cross-linked hydrogels promising materials for medical and biosensing fields.