Dimensional stability of lotus leaf-like nanostructure superhydrophobic bamboo by modification using xylan

BioResources ◽  
2020 ◽  
Vol 15 (2) ◽  
pp. 3443-3457
Author(s):  
Xun Gao ◽  
Ling Su ◽  
Guiquan Jiang ◽  
Jiuyin Pang ◽  
Lin Lin
Keyword(s):  
Dimensional Stability ◽  
Soft Lithography ◽  
Mass Fraction ◽  
Weight Percent Gain ◽  
Weight Percent ◽  
Water Contact ◽  
Lotus Leaf ◽  
Force Microscopy ◽  
Atomic Force ◽  
Superhydrophobic Property

Xylan extracted from corncobs was used to modify bamboo and to improve its dimensional stability. A lotus leaf-like surface was prepared on the modified bamboo using a fresh lotus leaf and polydimethylsiloxane (PDMS) as the template and seal via soft lithography. The dimensional stability of bamboo was tested via anti-shrinkage efficiency (ASE), moisture excluding efficiency (MEE), weight percent gain (WPG), and its superhydrophobic property. The microstructures of lotus-like bamboo surface were analyzed via water contact angle (WCA), scanning electron microscopy, and atomic force microscopy (AFM). The study found that with increasing mass fraction of xylan content, the anti-swelling property and WPG of modified bamboo increased accordingly. When the mass fraction of xylan was 10%, its WPG was the largest (2.21%), and xylan had a better compatibilization effect on bamboo. The dimensional stability of bamboo was improved to a certain extent by xylan. Moreover, the anisotropy and superhydrophobicity of the lotus leaf-like bamboo treated by xylan were noticeably improved after modification, such that the WCA of the transverse, radial, and tangential sections were 157.5º, 145.5º, and 137.5º, respectively. This research lays a foundation for studies of dimensional stability of bamboo and the mechanism of modification to achieve hydrophobic properties.

Development of leftover rice/gelatin interpenetrating polymer network films for food packaging

2021 ◽  
Vol 10 (1) ◽  
pp. 37-48
Author(s):  
Sijia Li ◽  
Chun Shao ◽  
Zhikun Miao ◽  
Panfang Lu
Keyword(s):  
Food Packaging ◽  
Polymer Network ◽  
Raw Material ◽  
Interpenetrating Polymer Network ◽  
Waste Biomass ◽  
Practical Application ◽  
Water Contact ◽  
Force Microscopy ◽  
Atomic Force ◽  
Morphology Of Films

Abstract Waste biomass can be used as a raw material for food packaging. Different concentrations of gelatin (GEL) were introduced into the leftover rice (LR) system to form an interpenetrating polymer network (IPN) for improving the properties of the films. The structure and morphology of films were evaluated by Fourier transform infrared, scanning electron microscopy, and atomic force microscopy, which showed good compatibility between LR and GEL. The moisture content and oil absorption rate of IPN films were down by 105% and 182%, respectively, which showed better water and oil resistance than the LR film. In addition, increasing GEL concentration led to enhancement in the tensile strength of films from 2.42 to 11.40 MPa. The water contact angle value of the IPN films (117.53°) increased by 147% than the LR film (47.56°). The low haze of IPN films was obtained with the increment of the mutual entanglement of LR and GEL. The 30–50% GEL addition improved the water vapor barrier and thermal stability properties of the IPN films. This study highlights that LR as waste biomass can have a practical application in food packaging.

scholarly journals Synthesis of amphiphilic ABA triblock oligomer via ATRP and its surface properties

2017 ◽  
Vol 95 (5) ◽  
pp. 605-611 ◽  
Author(s):  
Lei Wang ◽  
Shaoqing Wen ◽  
Zhanxiong Li
Keyword(s):  
Photoelectron Spectroscopy ◽  
Microphase Separation ◽  
Gel Permeation Chromatography ◽  
Contact Angles ◽  
Chemical Compositions ◽  
Water Contact ◽  
Force Microscopy ◽  
Atomic Force ◽  
Poly Ethylene ◽  
Magnetic Resonances

A series of novel amphiphilic ABA-type poly(tridecafluorooctylacrylate)-poly(ethylene glycol)-poly(tridecafluorooctylacrylate) (henceforth referred to as p-TDFA-PEG-p-TDFA) triblock oligomers were successfully synthesized via atom transfer radical polymerization (ATRP) using well-defined Br-PEG-Br as macroinitiator and copper as catalyst. The block oligomers were characterized by Fourier transform infrared (FTIR) spectroscopy and 1H and 19F nuclear magnetic resonances (NMR). Gel permeation chromatography (GPC) showed that the block oligomers have been obtained with narrow molecular weight distributions of 1.22–1.33. X-ray photoelectron spectroscopy (XPS) was carried out to confirm the attachment of p-TDFA-PEG-p-TDFA onto the silicon substrate, together with the chemical compositions of p-TDFA-PEG-p-TDFA. The wetabilities of the oligomer films were measured by water contact angles (CAs). Water CAs of p-TDFA-PEG-p-TDFA film were measured and their morphologies were tested by atomic force microscopy (AFM). The result showed that the CAs of the oligomer films, which possess fluoroalkyl groups assembled on the outer surface, increase after heating due to the migration of fluoroalkyl groups and the resulted microphase separation of the p-TDFA-PEG-p-TDFA.

scholarly journals Superhydrophilic Coating with Antibacterial and Oil-Repellent Properties via NaIO4-Triggered Polydopamine/Sulfobetaine Methacrylate Polymerization

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2008
Author(s):  
Hsiu-Wen Chien ◽  
Hong-Yu Lin ◽  
Chau-Yi Tsai ◽  
Tai-Yu Chen ◽  
Wei-Nian Chen
Keyword(s):  
Surface Modification ◽  
Photoelectron Spectroscopy ◽  
Deposition Process ◽  
Water Contact ◽  
Water Separation ◽  
Force Microscopy ◽  
Atomic Force ◽  
Oil Water Separation ◽  
One Step ◽  
Oil Repellent

Superhydrophilic coatings have been widely used for the surface modification of membranes or biomedical devices owing to their excellent antifouling properties. However, simplifying the modification processes of such materials remains challenging. In this study, we developed a simple and rapid one-step co-deposition process using an oxidant trigger to fabricate superhydrophilic surfaces based on dopamine chemistry with sulfobetaine methacrylate (SBMA). We studied the effect of different oxidants and SBMA concentrations on surface modification in detail using UV–VIS spectrophotometry, dynamic light scattering, atomic force microscopy, X-ray photoelectron spectroscopy, and surface plasmon resonance. We found that NaIO4 could trigger the rate of polymerization and the optimum ratio of dopamine to SBMA is 1:25 by weight. This makes the surface superhydrophilic (water contact angle < 10°) and antifouling. The superhydrophilic coating, when introduced to polyester membranes, showed great potential for oil/water separation. Our study provides a complete description of the simple and fast preparation of superhydrophilic coatings for surface modification based on mussel-inspired chemistry.

Effect of Inorganic/Organic Hybrid on the Wettability of Polymer Nanofibrous Membranes

2013 ◽  
Vol 8 (4) ◽  
pp. 155892501300800 ◽  
Author(s):  
Ning Wu ◽  
Ying Sun ◽  
Yanan Jiao ◽  
Li Chen
Keyword(s):  
Water Contact ◽  
Tem Analysis ◽  
New Approach ◽  
Force Microscopy ◽  
Organic Hybrid ◽  
Atomic Force ◽  
Hybrid Nanofibers ◽  
Nanofibrous Membranes ◽  
Fibrous Membranes ◽  
Composite Fibrous Membranes

We report a new approach for improving the wettability of a poly (vinyl acetate) (PVAc) nanofiber membrane. The pure PVAc and hybrid PVAc/titanium dioxide (TiO2) nanofibrous membranes can be obtained by electrospinning the PVA solution and PVA/TiO2 hybrid sol with different TiO2 contents, respectively. The resultant samples were characterized by scanning electron microscopy (SEM), nitrogen volumetric adsorption apparatus (NVAA), water contact angle (WCA), atomic force microscopy (AFM) energy dispersive X-ray spectroscopy (EDX) and transmission electronic microscopy (TEM). It was found that the WCA of composite fibrous membranes was decreased from 109 to 36&deg; as the TiO2 content increased. The AFM, EDX and TEM analysis indicate that the wettability of PVAc/TiO2 hybrid nanofibers was mainly improved by surface roughness and surface hydrophilic groups.

Dewetting of Polymer Bilayers: Morphology and Kinetics

1994 ◽  
Vol 366 ◽  
Author(s):  
Alessandro Faldi ◽  
Karen I. Winey ◽  
Russell J. Composto
Keyword(s):  
Atomic Force Microscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Weight Percent ◽  
Force Microscopy ◽  
Atomic Force ◽  
Polymer Bilayers ◽  
Hole Profile ◽  
Interfacial Thermodynamics ◽  
Kinetics Of

ABSTRACTThe kinetics of de-wetting a polycarbonate (PC) film from a poly(styrene-coacrylonitrile) (SAN) copolymer film was monitored using optical microscopy. Whereas the SAN layer was stable upon annealing at 190°C, the PC layer dewetted the SAN and formed holes whose diameter increased linearly with time. Auger electron spectroscopy measurements confirmed that PC was fully removed from the interior of the hole. Upon varying the AN content, the dewetting velocity was found to be a minimum near 0.27 weight percent AN. This result is consistent with the interfacial thermodynamics between PC and SAN. Atomic force microscopy was used to provide a unique image of the hole profile.

scholarly journals Effect of Sputtering Temperature on Fluorocarbon Films: Surface Nanostructure and Fluorine/Carbon Ratio

Nanomaterials ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 848 ◽  
Author(s):  
Qi Zhao ◽  
Feipeng Wang ◽  
Kaizheng Wang ◽  
Guibai Xie ◽  
Wanzhao Cui ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Target Material ◽  
Chemical Compositions ◽  
Water Contact ◽  
Force Microscopy ◽  
Fluorocarbon Films ◽  
Atomic Force ◽  
Surface Nanostructure ◽  
Deposited Film ◽  
Fluorocarbon Film

In this work, fluorocarbon film was deposited on silicon (P/100) substrate using polytetrafluoroethylene (PTFE) as target material at elevated sputtering temperature. Field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) were employed to investigate the surface morphology as well as structural and chemical compositions of the deposited film. The surface energy, as well as the polar and dispersion components, were determined by water contact angle (WCA) measurement. The experimental results indicated that increasing sputtering temperature effectively led to higher deposition rate, surface roughness and WCA of the film. It was found that the elevated temperature contributed to increasing saturated components (e.g., C–F2 and C–F3) and decreasing unsaturated components (e.g., C–C and C–CF), thus enhancing the fluorine-to-carbon (F/C) ratio. The results are expected aid in tailoring the design of fluorocarbon films for physicochemical properties.

scholarly journals Polydopamine Linking Substrate for AMPs: Characterisation and Stability on Ti6Al4V

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3714
Author(s):  
Zuzanna Trzcińska ◽  
Marc Bruggeman ◽  
Hanieh Ijakipour ◽  
Nikolas J. Hodges ◽  
James Bowen ◽  
...  
Keyword(s):  
High Performance ◽  
Release Profile ◽  
Water Contact ◽  
Force Microscopy ◽  
Angle Measurements ◽  
Atomic Force ◽  
Contact Angle Measurements ◽  
Titanium Alloy Ti6al4v ◽  
Thickness Measurements

Infections are common complications in joint replacement surgeries. Eradicated infections can lead to implant failure. In this paper, analogues of the peptide KR-12 derived from the human cathelicidin LL-37 were designed, synthesised, and characterised. The designed antimicrobial peptides (AMPs) were attached to the surface of a titanium alloy, Ti6Al4V, by conjugation to a polydopamine linking substrate. The topography of the polydopamine coating was evaluated by electron microscopy and coating thickness measurements were performed with ellipsometry and Atomic Force Microscopy (AFM). The subsequently attached peptide stability was investigated with release profile studies in simulated body fluid, using both fluorescence imaging and High-Performance Liquid Chromatography (HPLC). Finally, the hydrophobicity of the coating was characterised by water contact angle measurements. The designed AMPs were shown to provide long-term bonding to the polydopamine-coated Ti6Al4V surfaces.

Evaluation of water related properties of birch wood products modified with different molecular weight phenol-formaldehyde oligomers

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Juris Grinins ◽  
Vladimirs Biziks ◽  
Janis Rizikovs ◽  
Ilze Irbe ◽  
Holger Militz
Keyword(s):  
Molecular Weight ◽  
Dimensional Stability ◽  
Phenol Formaldehyde ◽  
Treated Wood ◽  
Weight Percent Gain ◽  
Weight Percent ◽  
Solid Wood ◽  
Wood Products ◽  
Birch Wood ◽  
Molecular Weights

Abstract This study investigated the effect of phenol-formaldehyde (PF) resin treatment on the dimensional stability of birch solid wood and plywood. Therefore, three different low molecular weight PF resins with average molecular weights (M w ) of 292, 528, and 884 g/mol were synthesized and used for silver birch (Betula pendula) solid wood (20 × 20 × 20 mm3) and veneer (100 × 100 × 1.4 and 300 × 300 × 1.4 mm3) impregnation to produce plywood. The weight percent gain (WPG) and bulking after curing of resin treated wood specimens were determined. The leaching was performed to evaluate the PF resin fixation stability. All tested resins at all concentrations were similarly fixed in wood blocks after the leaching (1.5–2.0% WPG loss). The dimensional stability of birch wood after treatment with all tested PF resins was significantly improved. The anti-swelling efficiency (ASE) of birch wood blocks treated with PF resins after seven water soaking-drying cycles was in the range of 39–53%, 46–65% and 49–65% using 10, 15 and 20% solution concentrations, respectively. Whereas, the ASE of plywood obtained from veneers treated with 10% of PF solution was improved by 6–20%. The equilibrium moisture content (EMC) and volumetric swelling (VS) of PF treated plywood at 98% of relative humidity (RH) decreased significantly. All PF resin treated plywood surfaces were more hydrophobic compared to untreated plywood.

Surface Topography of Vinyltriethoxysilane Films Deposited on the Silicon Dioxide Substrate (0001) Investigated by Atomic Force Microscopy

2011 ◽  
Vol 418-420 ◽  
pp. 513-522
Author(s):  
Yun Wu ◽  
Chu Jiang Cai ◽  
Zhi Gang Shen ◽  
Shu Lin Ma ◽  
Yu Shan Xing
Keyword(s):  
Atomic Force Microscopy ◽  
Silicon Dioxide ◽  
Surface Topography ◽  
Vapor Phase ◽  
Solution Method ◽  
Water Contact ◽  
Force Microscopy ◽  
Vapor Phase Deposition ◽  
Atomic Force ◽  
Deposition Processes

The surface topography and growth behavior of self-assembled monolayers (SAMs) formed from vinyltriethoxysilane (VTES) at a constant temperature (20°C) on silicon dioxide substrates were investigated using atomic force microscopy (AFM). Two methods for silanization were introduced: vapor phase deposition and deposition from a solution. The influence of deposition conditions on the topography of silane films was also studied. The property of modified SiO2substrates surface was characterized by static water contact angle measurements. The experimental results revealed that the silane films deposited from the solution method grew via islands, whereas this is not the case for vapor phase deposition. The roughness of the layers deposited via solution method first decreased and then increased with the VTES concentration increasing, while the roughness of the layers deposited via vapor phase increased straight. Furthermore, the adsorption types for silane being adsorbed on SiO2substrates were also investigated. The results indicated that there were two adsorption types in both deposition processes: physisorption and chemisorption.

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