Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
Add more filters










Publication year range
1.
Heliyon ; 10(11): e31787, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38845927

ABSTRACT

Utilization of vegetable tannins in leather processing is one of the convenient solutions to protect the environment pollution. Herein, the banana bunch and syrup of banana stem are utilized to prepare an ecofriendly tanning agent. The yield of banana bunch extraction efficiency is found 69.80 %. FT-IR analysis confirmed the presence of condensed type tanning component owing to the bearing of different polyphenolic groups. The content of tannins in extracted banana bunch and stem syrup is 3.13 % and 2.6 %, respectively. The phenolic content in the banana bunch extract is determined to be 1332.37 mg GAE/100g of dried weight and in syrup was 873.92 mg GAE/100g of dried weight. This makes it possible to be used as vegetable tanners. The extracted bunch and syrup are applied to re-tan leather and compared with conventionally used vegetable tanning agent (quebracho) in parallel. Tensile strength, tear strength and elongation percentage for the extracted banana bunch and syrup are obtained at 23.84 N/mm2, 68.26 N/mm, 47.07 %, and 22.97 N/mm2, 68.38 N/mm, 40.70 %, respectively. The softness is found 1.41 for the extracted bunch and 2.01 for the syrup. The grain crack load, distension at grain crack, strength at ball burst, distension at ball burst are 246.86 N, 13.24 mm, 530.77 N, 24.54 mm for banana stem syrup and 338.77 N, 13.42 mm, 460.65 N, 29.08 mm for bunch extract, respectively. The shrinkage temperatures recorded for banana bunch extract, syrup and Quebracho (control trial) tannins tanned leather samples are 76.5 °C, 75 °C and 84 °C subsequently. The flexing endurance of the bunch extract and syrup revealed acceptable values that are less than 4. Moreover, the bunch extract tanned leather shows greater thermal stability and for syrup it is similar with the quebracho tanned leather. All the results are satisfactory compared to the control trial. Finally, tanned leather is evaluated to assess the possibility of the newly developed tannin which proves its efficiency as a potential source of tanning material for the leather industry.

2.
Int J Biol Macromol ; 273(Pt 1): 132962, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38848827

ABSTRACT

The preparation of natural polymer-based highly conductive hydrogels with reliable durability for applications in supercapacitors (SCs) is still challenging. Herein, a facile method to prepare alkaline lignin (AL)-based polypyrrole (PPy)-rich, high-conductive PPy@AL/PEGDGE gel was reported, where AL was used as a dopant, polyethylene glycol diglycidyl ether (PEGDGE) as a cross-linking agent, and PPy as a conducting polymer. The PPy@AL/PEGDGE gel electrode materials with hollow structures were prepared by electrochemical deposition and chemical etching method and then assembled into sandwich-shaped SCs. Cyclic voltammetry (CV), galvanotactic charge discharge (GCD), electrochemical impedance spectroscopy (EIS) and cycling stability tests of the PPy@AL/PEGDGE SCs were performed. The results demonstrated that the SCs can achieve a conductivity of 25.9 S·m-1 and a specific capacitance of 175 F·g-1, which was 127.4 % higher compared to pure PPy (77 F·g-1) electrode. The highest energy density and power density for the SCs were obtained at 23.06 Wh·kg-1 and 5376 W·kg-1, respectively. In addition, the cycling performance was also higher than that of pure PPy assembled SCs (50 %), and the capacitance retention rate can reach 72.3 % after 1000 cycles. The electrode materials are expected to be used as sensor and SCs devices.

3.
Int J Biol Macromol ; 264(Pt 2): 130770, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38467230

ABSTRACT

Traditional adhesives easily release toxic gases during the preparation process or apply to wood composite products, which have adverse effects on the human body and the environment. Herein, an all-water-based high-performance wood adhesive is prepared using TEMPO-oxidized cellulose nanofiber (TOCNF), acrylamide (AM), and tannic acid (TA) through free radical polymerization. Different characteristics of the prepared composites, including morphology, injectability, and adhesion properties, have been investigated. Results showed that the TA/TOCNF/PAM composite has excellent injectability. The addition of TA can enhance the lap shear strength of the TA/TOCNF/PAM composites and with the increment of TA content, the lap shear strength gradually decreases. The formation of effective hydrogen bonds and Van der Waals interaction among the rich functional groups in the composite, lead to strong lap shear strength on different substrates. The composite with 5.0 g of AM, 5.0 g of the TOCNF suspension and 0.1 g TA possesses a high lap shear strength of 10.5 MPa on wood and 1.5 MPa on aluminium. Based on strong adhesion properties and excellent injectability, the TA/TOCNF/PAM composites have great potential in the furniture construction and building industries.


Subject(s)
Cellulose, Oxidized , Nanofibers , Polyphenols , Humans , Adhesives/chemistry , Cellulose/chemistry , Nanofibers/chemistry , Wood/chemistry , Water/analysis , Cellulose, Oxidized/analysis
4.
Int J Biol Macromol ; 266(Pt 2): 131243, 2024 May.
Article in English | MEDLINE | ID: mdl-38554917

ABSTRACT

With the increment in global energy consumption and severe environmental pollution, it is urgently needed to explore green and sustainable materials. Inspired by nature, catechol groups in mussel adhesion proteins have been successively understood and utilized as novel biomimetic materials. In parallel, cellulose presents a wide class of functional materials rating from macro-scale to nano-scale components. The cross-over among both research fields alters the introduction of impressive materials with potential engineering properties, where catechol-containing materials supply a general stage for the functionalization of cellulose or cellulose derivatives. In this review, the role of catechol groups in the modification of cellulose and cellulose derivatives is discussed. A broad variety of advanced applications of cellulose-based catechol-containing materials, including adhesives, hydrogels, aerogels, membranes, textiles, pulp and papermaking, composites, are presented. Furthermore, some critical remaining challenges and opportunities are studied to mount the way toward the rational purpose and applications of cellulose-based catechol-containing materials.


Subject(s)
Catechols , Cellulose , Cellulose/chemistry , Catechols/chemistry , Hydrogels/chemistry , Adhesives/chemistry , Textiles , Animals , Biomimetic Materials/chemistry
5.
ACS Omega ; 9(5): 5854-5861, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38343987

ABSTRACT

Hydrogels have drawn intensive attention as fascinating materials for biomedicine. However, fabricating hydrogels with injectable and self-healing properties remains a challenge. Herein, we reported a biocompatible poly(N-vinylpyrrolidone)/carboxymethyl cellulose (PVP/CMC) hydrogel with excellent injectable and self-healing properties. The PVP/CMC hydrogel exhibits good biocompatible, injectable, and self-healing properties. The sol-gel transition of PVP/CMC hydrogels demonstrates an outstanding self-healing behavior, and the bisected hydrogels can self-heal within 30 s. The hydrogels have a good swelling ratio, and the swelling ratio increases with increasing amount of CMC in PVP and reaches a maximum of 2850% at a 1.0:1.5 PVP and CMC ratio. In addition, the hydrogel possesses excellent drug release capacity, and its drug release rate reaches 70%. Moreover, the release of 4-aminosalicylic acid (4-ASA) in the hydrogel can be controlled by adjusting the proportion of the hydrogel. The PVP/CMC hydrogel with excellent biocompatible, injectable, and self-healing properties has great potential for applications in drug release.

6.
Heliyon ; 10(4): e25544, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38384561

ABSTRACT

In Bangladesh, the annual production of rubber seeds is typically left untapped although the seeds contained a high percentage of oil but underutilized without any value-added utilization. This study aims to evaluate the geographical effect on physicochemical properties, fatty acid composition and the antimicrobial activity of oil extracted from rubber seeds. Seeds were collected from three different regions of Bangladesh and the oil was extracted by the soxhlet method using n-hexane as a solvent. Results demonstrated that the geographical regions have some significant effect on the properties of rubber seed oil (RSO). The physicochemical properties of RSO varied from region to region. For example, the percent of yield, higher heating value, and flash point varied from 50.0 to 50.8 %, 31.8-33.3 kJ/g, and 237-245 °C, respectively. The chemical parameters, such as acid value, iodine value, and hydroxyl value varied from 13.3 to 18.2 mg KOH/g, 132-137 g I2/100g, and 47.7-55.8 mg KOH/g, respectively. Chromatographic analysis showed that RSO mainly contains palmitic, linoleic, linolenic, and stearic acid. Regional variations were also seen in the composition of these fatty acids. Most notably, regardless of the rubber seeds collected from various locations, RSO exhibited inhibitory activity against only gram positive bacteria. The zone of inhibition range for different tested gram positive bacteria was 2.33-11.17 mm irrespective of different RSO samples.

7.
ACS Omega ; 9(3): 3877-3884, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38284020

ABSTRACT

Conventional adhesives have poor underwater adhesion and harm to human health and the environment during their use, which largely limits their practical applications. Herein, we synthesized cellulose-based adhesives with underwater adhesion and biocompatibility by grafting N-(3,4-dihydroxyphenethyl)methacrylamide into the cellulose chain via atom transfer radical polymerization (ATRP). FTIR, 1H NMR, and XPS analyses ensured the successful preparation of the cellulose-based adhesive polymers. The different properties of the prepared adhesives, including swelling ratio, adhesion strength, and biocompatibility are examined. Results found that the lap shear strength is enhanced by increasing the catechol content. When catechol content is 27.2 mol %, cellulose-based adhesive with the addition of Fe3+ possesses a strong lap shear strength of 2.13 MPa in a dry environment, 0.10 MPa underwater, and 0.16 MPa under seawater for iron substrate, respectively. In addition, the cell culture test demonstrated that the prepared adhesives have outstanding biocompatibility. The cellulose-based adhesives with underwater adhesion and biocompatibility have potential applications in biomedicine, electronic engineering, and construction fields.

8.
Int J Biol Macromol ; 256(Pt 1): 128345, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38007011

ABSTRACT

Aerogels as drug carriers have the characteristics of a large specific surface area, high porosity and an elastic skeleton structure. Compared with traditional drug carriers, the use of aerogels as drug carriers can avoid the complexity of drug delivery and improve the efficiency of drug loading. In this work, the oxidation of tunicate cellulose nanocrystals (tCNCs) with NaIO4 was used to prepare di-aldehyde tunicate cellulose nanocrystals (D-tCNCs). Tetracycline (TC) was used as a drug model and pH-responsive drug-loaded aerogels were prepared by the Schiff base reaction between TC and the aldehyde group on D-tCNCs. The chemical structure, crystallinity, morphology, compression properties, porosity, swelling rate and drug loading properties were investigated by FT-IR, XRD, SEM and universal testing machines. The results showed that the porosity and equilibrium swelling ratio of the D-tCNC-TC aerogels were 95.87 % and 17.52 g/g, respectively. The stress of the D-tCNC-TC aerogel at 15 % compression was 0.07 MPa. Moreover, the analysis of drug-loaded aerogels indicated that the drug loading and encapsulation rates of D-tCNC-TC aerogels were 16.86 % and 78.75 %, respectively. In in vitro release experiments, the cumulative release rate of drug-loaded aerogel at pH = 1.2 and pH = 7.4 was 87.5 % and 79.3 %, respectively. These results indicated that D-tCNC-TC aerogels have good drug loading capacity and are pH-responsive in the pH range of 1.2 to 7.4. The prepared D-tCNC-TC aerogels are expected to be applied in drug delivery systems.


Subject(s)
Nanoparticles , Urochordata , Animals , Cellulose/chemistry , Spectroscopy, Fourier Transform Infrared , Drug Delivery Systems , Drug Carriers/chemistry , Nanoparticles/chemistry , Gels/chemistry
9.
Int J Biol Macromol ; 259(Pt 1): 129081, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38161007

ABSTRACT

Cellulose is the richest renewable polymer source on the earth. TEMPO-mediated oxidized cellulose nanofibers are deduced from enormously available wood biomass and functionalized with carboxyl groups. The preparation procedure of TOCNFs is more environmentally friendly compared to other cellulose, for example, MFC and CNCs. Due to the presence of functional carboxyl groups, TOCNF-based materials have been studied widely in different fields, including biomedicine, wastewater treatment, bioelectronics and others. In this review, the TEMPO oxidation mechanism, the properties and applications of TOCNFs are elaborated. Most importantly, the recent advanced applications and the beneficial role of TOCNFs in the various abovementioned fields are discussed. Furthermore, the performances and research progress on the fabrication of TOCNFs are summarized. It is expected that this timely review will help further research on the invention of novel material from TOCNFs and its applications in different advanced fields, including biomedicine, bioelectronics, wastewater treatment, and the energy sector.


Subject(s)
Cellulose, Oxidized , Nanofibers , Cyclic N-Oxides , Cellulose , Oxidation-Reduction
10.
Int J Biol Macromol ; 245: 125580, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37379941

ABSTRACT

Polymers obtained from biomass are a concerning alternative to petro-based polymers because of their low cost of manufacturing, biocompatibility, ecofriendly and biodegradability. Lignin as the second richest and the only polyaromatics bio-polymer in plant which has been most studied for the numerous applications in different fields. But, in the past decade, the exploitation of lignin for the preparation of new smart materials with improved properties has been broadly sought, because lignin valorization plays one of the primary challenging issues of the pulp and paper industry and lignocellulosic biorefinery. Although, well suited chemical structure of lignin comprises of many functional hydrophilic and active groups, such as phenolic hydroxyls, carboxyls and methoxyls, which provides a great potential to be applied in the preparation of biodegradable hydrogels. In this review, lignin hydrogel is covered with preparation strategies, properties and applications. This review reports some important properties, such as mechanical, adhesive, self-healing, conductive, antibacterial and antifreezing properties were then discussed. Furthermore, herein also reviewed the current applications of lignin hydrogel, including dye adsorption, smart materials for stimuli sensitive, wearable electronics for biomedical applications and flexible supercapacitors. Overall, this review covers recent progresses regarding lignin-based hydrogel and constitutes a timely review of this promising material.


Subject(s)
Lignin , Smart Materials , Lignin/chemistry , Hydrogels/chemistry , Polymers/chemistry , Adsorption
11.
Carbohydr Polym ; 314: 120948, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37173049

ABSTRACT

Passive daytime radiative cooling (PDRC) materials simultaneously featuring aesthetic and safety distinctions demonstrate versatile applications beyond cooling buildings, while the integrated advantages of high strength, morphological reconfigurability, and sustainability remain challenging for the conventional PDRC materials. Herein, we designed a robust, custom-shaped and eco-friendly cooler via a scalable solution-processable strategy, involving the nano-scale assembly of nano cellulose (NC) and inorganic nanoparticle (e.g., ZrO2, SiO2, BaSO4, and hydroxyapatite). The robust cooler shows an interesting "brick-and-mortar" structure, where the NC constructs interwoven framework (as brick structure) and the inorganic nanoparticle uniformly locates in the skeleton (as mortar structure), collectively contributing to high mechanical strength (>80 MPa) and flexibility. In addition, the structural and chemical distinctions enable our cooler to show a high solar reflectance (>96 %) and mid-infrared emissivity (>0.9), demonstrating a sub-ambient average temperature drop of 8.8 °C in long-term outdoor environments. The high-performance cooler with robustness, scalability and environmental friendliness, serves as a competitive participant toward the advanced PDRC materials in our low-carbon society.

12.
Int J Biol Macromol ; 242(Pt 3): 125010, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37217060

ABSTRACT

The highly conductive and elastic three-dimensional mesh porous material is an ideal platform for the fabrication of high electrical conductivity conductive aerogels. Herein, a multifunctional aerogel that is lightweight, highly conductive and stable sensing properties is reported. Tunicate nanocellulose (TCNCs) with a high aspect ratio, high Young's modulus, high crystallinity, good biocompatibility and biodegradability was used as the basic skeleton to prepare aerogel by freeze-drying technique. Alkali lignin (AL) was used as the raw material, polyethylene glycol diglycidyl ether (PEGDGE) was used as the cross-linking agent, and polyaniline (PANI) was used as the conductive polymer. Preparation of aerogels by freeze-drying technique, in situ synthesis of PANI, and construction of highly conductive aerogel from lignin/TCNCs. The structure, morphology and crystallinity of the aerogel were characterized by FT-IR, SEM, and XRD. The results show that the aerogel has good conductivity (as high as 5.41 S/m) and excellent sensing performance. When the aerogel was assembled as a supercapacitor, the maximum specific capacitance can reach 772 mF/cm2 at 1 mA/cm2 current density, and maximum power and energy density can reach 59.4 µWh/cm2 and 3600 µW/cm2, respectively. It is expected the aerogel can be applied in the field of wearable devices and electronic skin.


Subject(s)
Alkalies , Lignin , Spectroscopy, Fourier Transform Infrared , Electric Conductivity
13.
Polymers (Basel) ; 15(2)2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36679152

ABSTRACT

In this paper, porous scaffolds based on composite hydrogels were fabricated using polydopamine (PDA), chondroitin sulfate (CS), and polyvinyl alcohol (PVA) via the freezing/thawing method. Different characteristics of the prepared composite hydrogels, including the pore sizes, compression strength, lap shear strength, mass loss, and cytocompatibility were investigated. Scanning electron microscope images (SEM) displayed the hydrogel pore sizes, ranging from 20 to 100 µm. The composite hydrogel exhibited excellent porosity of 95.1%, compression strength of 5.2 MPa, lap shear strength of 21 kPa on porcine skin, and mass loss of 16.0%. In addition, the composite hydrogel possessed good relative cell activity of 97%. The PDA/CS/PVA hydrogel is cytocompatible as a starting point, and it can be further investigated in tissue engineering.

14.
Int J Biol Macromol ; 214: 77-90, 2022 Aug 01.
Article in English | MEDLINE | ID: mdl-35691432

ABSTRACT

We developed a highly conductive and flexible, anti-freezing sulfonated lignin (SL)-containing polyacrylic acid (PAA) (SL-g-PAA-Ni) hydrogel, with a high concentration of NiCl2. Ni2+ contributes multi-functions to the preparation of the hydrogel and its final properties, such as fast polymerization reaction as a result of the presence of redox pairs of Ni3+/Ni2+ and hydroquinone/quinone, and anti-freezing properties of the hydrogel due to the salt effects of NiCl2 so that at -20 °C the hydrogel shows similar properties to those at the room temperature. Thanks to the effective coordinations of Ni2+ with catecholic groups and carboxylic groups, as well as the rich hydrogen bonding capacity, the resultant hydrogel possesses excellent mechanical properties. High ionic conductivity (6.85 S·m-1) of the hydrogel is obtained due to the supply of high concentration of Ni2+. Moreover, the ionic solvation effect of NiCl2 in the hydrogel imparts excellent water retention ability, with water retention of ~93 % after 21-day storage. The SL-g-PAA-Ni hydrogel can accurately detect various human motions at -20 °C. The supercapacitor assembled from SL-g-PAA-Al hydrogel at -20 °C manifests a high specific capacitance of 252 F·g-1, with maximum energy density of 26.97 Wh·kg-1, power density of 2667 W·kg-1, and capacitance retention of 96.7 % after 3000 consecutive charge-discharge cycles.


Subject(s)
Hydrogels , Lignin , Electric Conductivity , Humans , Polymerization , Water
15.
Int J Biol Macromol ; 207: 48-61, 2022 May 15.
Article in English | MEDLINE | ID: mdl-35247419

ABSTRACT

Herein, we design a dynamic redox system of using high contents of lignosulfonate (LS) and Al3+ to prepare poly acrylic acid (PAA) (LS-g-PAA-Al) hydrogels. The presence of high LS and Al3+ contents, in combination with the effective Al3+ complexes formed, renders the resultant hydrogel with some unique attributes, including excellent ionic conductivity (as high as 7.38 S·m-1) and antibacterial activity; furthermore, a very fast gelation (in 1 min) was obtained. As a flexible strain sensor, the LS-g-PAA-Al hydrogel with high conductivity demonstrates superior sensitivity in human movement detection. In addition, the rich anionic hydrophilic groups, such as sulfonic groups, phenolic hydroxyl groups, in the hydrogels impart the resultant hydrogels with excellent adsorption capacity for cationic dyes: when using Rhodamine B (RB) as a model cationic dye, the adsorption capacity of the resultant hydrogel reaches 334.64 mg·g-1; as a moist-induced power generator, it generates maximum 150.5 mV open circuit voltage with moist air flow. When the hydrogel electrolyte is assembled into a supercapacitor assembly, it shows high specific capacitance of 245.4 F·g-1, with the maximum energy density of 21.8 Wh·kg-1, power density of 2.37 kW·kg-1, and capacitance retention of 95.1% after 5000 consecutive charge-discharge cycles.


Subject(s)
Hydrogels , Lignin , Anti-Bacterial Agents/pharmacology , Coloring Agents , Electric Conductivity , Humans
16.
Int J Biomater ; 2022: 8401528, 2022.
Article in English | MEDLINE | ID: mdl-35313478

ABSTRACT

Because of the alarming rate of human population growth, technological improvement should be needed to save the environment from pollution. The practice of business as usual on material production is not creating a circular economy. The circular economy refers to an economic model whose objective is to produce goods and services sustainably, by limiting the consumption and waste of resources (raw materials, water, and energy). Fungal-based composites are the recently implemented technology that fulfills the concept of the circular economy. It is made with the complex of fungi mycelium and organic substrates by using fungal mycelium as natural adhesive materials. The quality of the composite depends on both types of fungi and substrate. To ensure the physicochemical property of the fabricated composite, mycelium morphology, bimolecular content, density, compressive strength, thermal stability, and hydrophobicity were determined. This composite is proven to be used for different applications such as packaging, architectural designs, walls, and insulation. It also has unique features in terms of low cost, low emission, and recyclable.

17.
Biomacromolecules ; 23(3): 766-778, 2022 03 14.
Article in English | MEDLINE | ID: mdl-35049296

ABSTRACT

Preparation of natural polymer-based highly conductive hydrogels with tunable mechanical properties for applications in flexible electronics is still challenging. Herein, we report a facile method to prepare lignin-based Fe3+-rich, high-conductivity hydrogels via the following two-step process: (1) lignin hydrogels are prepared by cross-linking sulfonated lignin with poly(ethylene glycol) diglycidyl ether (PEGDGE) and (2) Fe3+ ions are impregnated into the lignin hydrogel by simply soaking in FeCl3. Benefiting from Fe3+ ion complexation with catechol groups and other functional groups in lignin, the resultant hydrogels exhibit unique properties, such as high conductivity (as high as 6.69 S·m-1) and excellent mechanical and hydrophobic properties. As a strain sensor, the as-prepared lignin hydrogel shows high sensitivity when detecting various human motions. With the flow of moist air, the Fe3+-rich lignin hydrogel generates an output voltage of 162.8 mV. The assembled supercapacitor of the hydrogel electrolyte demonstrates a high specific capacitance of 301.8 F·g-1, with a maximum energy density of 26.73 Wh·kg-1, a power density of 2.38 kW·kg-1, and a capacitance retention of 94.1% after 10 000 consecutive charge-discharge cycles. These results support the conclusion that lignin-based Fe3+-rich, high-conductivity hydrogels have promising applications in different fields, including sensors and supercapacitors, rendering a new platform for the value-added utilization of lignin.


Subject(s)
Hydrogels , Lignin , Electric Capacitance , Electric Conductivity , Humans , Hydrogels/chemistry , Ions , Lignin/chemistry , Polymers/chemistry
18.
Carbohydr Res ; 511: 108488, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34875481

ABSTRACT

First time aerogels composite with super hydrophobic properties were developed by using tunicate cellulose nanocrystals (TCNC), which expanded the application scope of animal cellulose resources. In this study, the TCNC was firstly cross-linked with silica and methyltrimethylsilane (MTMS), further coated with fluorodopa to form an aerogel with super hydrophobic properties. The aerogel was characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectra (FT-IR), and X-ray photoelectron spectroscopy (XPS). Results indicated that the contact angle of aerogel was 158.7°, which showed good hydrophobicity. The composite aerogel has superior stability in wide pH range, after 72 h immersion in pH = 0 and 12 solutions, the contact angle was still greater than 150°. The aerogel shows excellent oil-water separation ability and it can be repeatedly used more than 10 times. The separation efficiency can all reach more than 90% for different water-oil mixtures. This synthesized super hydrophobic aerogels derived from tunicate cellulose has greatly extended the application of marine animal celluloses.


Subject(s)
Nanoparticles , Urochordata , Animals , Cellulose/chemistry , Gels/chemistry , Hydrophobic and Hydrophilic Interactions , Spectroscopy, Fourier Transform Infrared
19.
Int J Biol Macromol ; 187: 189-199, 2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34265336

ABSTRACT

Lignin, an abundant natural polymer but presently under-utilized, has received much attention for its green/sustainable advantages. Herein, we report a facile method to fabricate lignosulfonate (LS) ionic hydrogels by simple crosslinking with poly (ethylene glycol) diglycidyl ether (PEGDGE). The as-obtained LS-PEGDGE hydrogels were comprehensively characterized by mechanical measurements, FT-IR, and SEM. The rich sulfonic and phenolic hydroxyl groups in LS hydrogels play key roles in imparting multifunctional smart properties, such as adhesiveness, conducting, sensing and dye adsorption, as well as superconductive behavior when increasing the moisture content. The hydrogels have a high adsorption capacity for cationic dyes, using methylene blue as a model, reaching 211 mg·g-1. As a moist-induced power generator, the maximum output voltage is 181 mV. The LS-PEGDGE hydrogel-based flexible strain sensors exhibit high sensitivity when detecting human movements. As the hydrogel electrolyte, the assembled supercapacitor shows high specific capacitance of 236.9 F·g-1, with the maximum energy density of 20.61 Wh·kg-1, power density of 2306.4 W·kg-1, and capacitance retention of 92.9% after 10,000 consecutive charge-discharge cycles. Therefore, this multifunctional LS hydrogels may have promising applications in various fields, providing a new platform for the value-added utilization of lignin from industrial waste.


Subject(s)
Coloring Agents/chemistry , Electric Capacitance , Epoxy Resins/chemistry , Hydrogels/chemistry , Lignin/analogs & derivatives , Methylene Blue/chemistry , Water Pollutants, Chemical/chemistry , Lignin/chemistry
20.
Polymers (Basel) ; 12(12)2020 Dec 21.
Article in English | MEDLINE | ID: mdl-33371516

ABSTRACT

Tunicate is a kind of marine animal, and its outer sheath consists of almost pure Iß crystalline cellulose. Due to its high aspect ratio, tunicate cellulose has excellent physical properties. It draws extensive attention in the construction of robust functional materials. However, there is little research on its biological activity. In this study, cellulose enzymatic hydrolysis was conducted on tunicate cellulose. During the hydrolysis, the crystalline behaviors, i.e., crystallinity index (CrI), crystalline size and degree of polymerization (DP), were analyzed on the tunicate cellulose. As comparisons, similar hydrolyses were performed on cellulose samples with relatively low CrI, namely α-cellulose and amorphous cellulose. The results showed that the CrI of tunicate cellulose and α-cellulose was 93.9% and 70.9%, respectively; and after 96 h of hydrolysis, the crystallinity, crystalline size and DP remained constant on the tunicate cellulose, and the cellulose conversion rate was below 7.8%. While the crystalline structure of α-cellulose was significantly damaged and the cellulose conversion rate exceeded 83.8% at the end of 72 h hydrolysis, the amorphous cellulose was completely converted to glucose after 7 h hydrolysis, and the DP decreased about 27.9%. In addition, tunicate cellulose has high anti-mold abilities, owing to its highly crystalized Iß lattice. It can be concluded that tunicate cellulose has significant resistance to enzymatic hydrolysis and could be potentially applied as anti-biodegradation materials.

SELECTION OF CITATIONS
SEARCH DETAIL
...