scholarly journals Laser Processing of Polymer Films Fabricated from PHAs Differing in Their Monomer Composition

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1553
Author(s):  
Tatiana Volova ◽  
Alexey Golubev ◽  
Ivan Nemtsev ◽  
Anna Lukyanenko ◽  
Alexey Dudaev ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Water Contact Angle ◽  
Continuous Wave ◽  
Cell Attachment ◽  
Colorimetric Assay ◽  
Film Surface ◽  
Degree Of Crystallinity ◽  
Roughness Parameters ◽  
Water Contact

The study reports results of using a CO2-laser in continuous wave (3 W; 2 m/s) and quasi-pulsed (13.5 W; 1 m/s) modes to treat films prepared by solvent casting technique from four types of polyhydroxyalkanoates (PHAs), namely poly-3-hydroxybutyrate and three copolymers of 3-hydroxybutyrate: with 4-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate (each second monomer constituting about 30 mol.%). The PHAs differed in their thermal and molecular weight properties and degree of crystallinity. Pristine films differed in porosity, hydrophilicity, and roughness parameters. The two modes of laser treatment altered these parameters and biocompatibility in diverse ways. Films of P(3HB) had water contact angle and surface energy of 92° and 30.8 mN/m, respectively, and average roughness of 144 nm. The water contact angle of copolymer films decreased to 80–56° and surface energy and roughness increased to 41–57 mN/m and 172–290 nm, respectively. Treatment in either mode resulted in different modifications of the films, depending on their composition and irradiation mode. Laser-treated P(3HB) films exhibited a decrease in water contact angle, which was more considerable after the treatment in the quasi-pulsed mode. Roughness parameters were changed by the treatment in both modes. Continuous wave line-by-line irradiation caused formation of sintered grooves on the film surface, which exhibited some change in water contact angle (76–80°) and reduced roughness parameters (to 40–45 mN/m) for most films. Treatment in the quasi-pulsed raster mode resulted in the formation of pits with no pronounced sintered regions on the film surface, a more considerably decreased water contact angle (to 67–76°), and increased roughness of most specimens. Colorimetric assay for assessing cell metabolic activity (MTT) in NIH 3T3 mouse fibroblast culture showed that the number of fibroblasts on the films treated in the continuous wave mode was somewhat lower; treatment in quasi-pulsed radiation mode caused an increase in the number of viable cells by a factor of 1.26 to 1.76, depending on PHA composition. This is an important result, offering an opportunity of targeted surface modification of PHA products aimed at preventing or facilitating cell attachment.

Addition of Cellulose Nanofibers to Control Surface Roughness for Hydrophobic Ceramic Coatings

2021 ◽  
Vol 21 (8) ◽  
pp. 4492-4497
Author(s):  
Eun Ae Shin ◽  
Gye Hyeon Kim ◽  
Jeyoung Jung ◽  
Sang Bong Lee ◽  
Chang Kee Lee
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Surface Energy ◽  
Water Contact Angle ◽  
Ceramic Coating ◽  
Cellulose Nanofibers ◽  
Ceramic Coatings ◽  
Coating Material ◽  
Textured Surface ◽  
Water Contact

Hydrophobic ceramic coatings are used for a variety of applications. Generally, hydrophobic coating surfaces are obtained by reducing the surface energy of the coating material or by forming a highly textured surface. Reducing the surface energy of the coating material requires additional costs and processing and changes the surface properties of the ceramic coating. In this study, we introduce a simple method to improve the hydrophobicity of ceramic coatings by implementing a textured surface without chemical modification of the surface. The ceramic coating solution was first prepared by adding cellulose nanofibers (CNFs) and then applied to a polypropylene (PP) substrate. The surface roughness increased as the amount of added CNFs increased, increasing the water contact angle of the surface. When the amount of CNFs added was corresponding to 10% of the solid content, the surface roughness average of the area was 43.8 μm. This is an increase of approximately 140% from 3.1 μm (the value of the surface roughness of the surface without added CNFs). In addition, the water contact angle of the coating with added CNF increased to 145.0°, which was 46% higher than that without the CNFs. The hydrophobicity of ceramic coatings with added CNFs was better because of changes in the surface topography. After coating and drying, the CNFs randomly accumulated inside the ceramic coating layer, forming a textured surface. Thus, hydrophobicity was improved by implementing a rugged ceramic surface without revealing the surface of the CNFs inside the ceramic layer.

Preparation of Hydrophobic Nylon Fabric

2016 ◽  
Vol 11 (1) ◽  
pp. 155892501601100
Author(s):  
Jinmei Du ◽  
Lulu Zhang ◽  
Jing Dong ◽  
Ying Li ◽  
Changhai Xu ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Surface Energy ◽  
Water Contact Angle ◽  
Sem Images ◽  
Water Contact ◽  
Carboxyl Content ◽  
Factors Affecting ◽  
Nylon Fabric ◽  
Butanetetracarboxylic Acid

Surface roughness and surface energy are two important factors affecting the hydrophobicity of nylon fabric. In this study, nylon fabric was treated for hydrophobicity with tetrabutyltitanate (TBT) and octadecylamine (OA) which were respectively responsible for increasing surface roughness and reducing surface energy. In order to enhance the hydrophobicity, In order to further enhance hydrophobicity by increasing available reactive sites, 1,2,3,4–butanetetracarboxylic acid (BTCA) was applied as a pretreatment to the nylon fabric It was found that the carboxyl content of nylon was increased by the BTCA pretreatment. SEM images showed that the TBT treatment produced small particles on nylon fabric which made surface rough. The water contact angle of nylon fabric treated with BTCA, TBT and OA was measured to be 134°, which was much greater than the water contact angle of nylon fabric treated only with OA. This indicated that the surface roughness resulting from the TBT treatment played an important role in improving hydrophobicity of the treated nylon fabric. The resistance to water penetration and the repellency of water spray of nylon fabric treated with BTCA, TBT and OA were respectively measured to be 27.64 mbar and 85 out of 100.

scholarly journals Superhydrophobic organosilicon-based coating system by a novel ultravoilet-curable method

2017 ◽  
Vol 7 ◽  
pp. 184798041770279 ◽  
Author(s):  
Baojiang Liu ◽  
Taizhou Tian ◽  
Jinlong Yao ◽  
Changgen Huang ◽  
Wenjun Tang ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Silica Nanoparticles ◽  
Water Contact Angle ◽  
Cotton Fabric ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Water Repellent ◽  
Step Method ◽  
Water Contact

A robust superhydrophobic organosilica sol-gel-based coating on a cotton fabric substrate was successfully fabricated via a cost-effective one-step method. The coating was prepared by modification of silica nanoparticles with siloxane having long alkyl chain that allow to reduce surface energy. The coating on cotton fabric exhibited water contact angle of 151.6°. The surface morphology was evaluated by scanning electron microscopy, and surface chemical composition was measured with X-ray photoelectron spectroscopy. Results showed the enhanced superhydrophobicity that was attributed to the synergistic effect of roughness created by the random distribution of silica nanoparticles and the low surface energy imparted of long-chain alkane siloxane. In addition, the coating also showed excellent durability against washing treatments. Even after washed for 30 times, the specimen still had a water contact angle of 130°, indicating an obvious water-repellent property. With this outstanding property, the robust superhydrophobic coating exhibited a prospective application in textiles and plastics.

Photocrosslinked PVDF-based star polymer coatings: an all-in-one alternative to PVDF/PMMA blends for outdoor applications

2017 ◽  
Vol 8 (20) ◽  
pp. 3045-3049 ◽  
Author(s):  
Gérald Lopez ◽  
Marc Guerre ◽  
Bruno Améduri ◽  
Jean-Pierre Habas ◽  
Vincent Ladmiral
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Metal Surface ◽  
Water Contact Angle ◽  
Polymer Coatings ◽  
Star Polymer ◽  
Water Contact ◽  
Adhesion Properties ◽  
Pmma Blends

A 4-arm PVDF photocrosslinked coating displays outstanding adhesion properties to a metal surface, and tunable surface energy and water contact angle.

Improved Hydrophobicity of Silicon Dioxide Integrated Zinc-Tellurite Glass Surface

2017 ◽  
Vol 268 ◽  
pp. 87-91
Author(s):  
Syarinie Azmi ◽  
Ramli Arifin ◽  
Sib Krishna Ghoshal
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Surface Energy ◽  
Water Contact Angle ◽  
Glass Surface ◽  
Tellurite Glass ◽  
Hydrophobic Surfaces ◽  
Water Contact ◽  
Host Matrix ◽  
The Impact

Economically viable and maintenance free glass surfaces with improved hydrophobicity are highly demanding in the recent nanotechnology era. Deposition of pollutants and dirt on glass surface that not only causes visual obscurity but also damages the cultural heritages are still to be researched intensely. It is documented that excellent hydrophobic surfaces (with contact angle greater than 90o) can be achieved by controlling the surface wettability, where liquid droplets remain spherical on such surfaces. Selection of materials and the preparation method play a significant role towards such accomplishments. Stirred by this idea, we explored the feasibility of fabricating super-hydrophobic tellurite glass systems by facilely varying the compositions of different constituents. Highly transparent and thermally stable ternary tellurite glass system with chemical composition of (80-x)TeO2 – xSiO2 – 20ZnO, where x = 0.00 to 0.20 mol% are synthesized via conventional melt-quenching method. Samples are characterized using Atomic Force Microscopy (AFM) and contact angle measurements. The impact of SiO2 concentrations variation on the surface roughness, surface energy, and hydrophobic properties are inspected. Glass surface roughness as much as 9.885 nm is attained. The optimal value of water contact angle is discerned to be 101.02° for 0.1 mol% of SiO2 incorporation into the amorphous tellurite host matrix. Besides, the surface energy revealed an inverse proportionality to the water contact angle. This achieved contact angle (greater than 90°) makes this hydrophobic glass surface beneficial for diverse applications. It is established that the present glass composition may be prospective for the development of super-hydrophobic surfaces.

The Study on the Synthesis of Polyfluoroacrylate

2013 ◽  
Vol 395-396 ◽  
pp. 351-354
Author(s):  
Qin Huan Yang
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Polymer Film ◽  
Water Contact Angle ◽  
Film Surface ◽  
Contact Angles ◽  
Fluoride Content ◽  
Water Contact ◽  
Copolymer Films ◽  
High Fluoride

Cationic polyfluoroacrylate has been synthesized in the dual presence of cationic and non-ionic emulsifiers. Optimization studies indicated that the optimal proportions of cationic emulsifier 1631 and non-ionic emulsifiers FSA and AEO-9 were 1.75%, 1.25%, and 0.08%, respectively. Under these conditions, the conversion to the polymer was 92.5%, the particle size was 142 nm, and the water contact angle on a polymer film surface was 94.0°. With increasing dosage of hydrocarbon emulsifier, the water contact angles of copolymer films decreased dramatically. The magnitude of this decrease for a polymer with low fluoride content was greater than that for a polymer with high fluoride content. The fluorinated emulsifier FSA behaved similarly to the hydrocarbon emulsifier.

Preparation and Characterization of Waterborne Fluorinated Polyurethane-Acrylate

2017 ◽  
Vol 753 ◽  
pp. 60-64
Author(s):  
Wei Yang ◽  
Ming Jian Song ◽  
Bin Xie ◽  
Yue Jing Zhou
Keyword(s):  
Contact Angle ◽  
Phase Separation ◽  
Water Contact Angle ◽  
Film Surface ◽  
Surface Hydrophobicity ◽  
Toluene Diisocyanate ◽  
Water Contact ◽  
Obvious Effect ◽  
Fluorinated Polyurethane ◽  
Polyurethane Acrylate

Fluorinated urethane-acrylic monomer (FUA) was synthesized using toluene diisocyanate (TDI), 1H, 1H, 2H, 2H-Perfluorooctanol(FOH) as well as hydroxyethyl methacrylate(HEMA), and then applied to prepare waterborne fluorinated polyurethane-acrylate (FPUA) via emulsion polymerization. The effect of FUA content on surface properties of latex films was evaluated by means of nuclear magnetic resonance (1H NMR), atomic force microscope (AFM) and water contact angle test. It is shown that FUA monomer content is related to phase separation of the film surface and water contact angle. As FUA content was increased from 0 wt% to 11.8 wt%, water contact angle was increased from 84° to 104.5°. Further increase of FUA has little influence on surface hydrophobicity but obvious effect on surface phase separation, and the reason which led to this phenomenon is described.

Study on Fluorocarbon Antifouling Coatings with Low Surface Energy

2011 ◽  
Vol 689 ◽  
pp. 445-449
Author(s):  
Chun Hong Qiu ◽  
Yu Hong Qi ◽  
Zhan Ping Zhang ◽  
Hui Gao
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Water Contact Angle ◽  
Dynamic Testing ◽  
Marine Diatom ◽  
Silicone Resin ◽  
Water Contact ◽  
Antifouling Coating ◽  
Low Surface Energy ◽  
Antifouling Coatings

To develop non-toxic marine antifouling coating, a series of antifouling coatings were prepared based on fluorocarbon copolymer. Based on the measurement of roughness and water contact angle, the attachment test of marine diatom and bacteria before and after dynamic testing in seawater, it has been investigated that the influence of three functional fillings and silicone resin on the performance of the antifouling coatings with low surface energy. The erosion rate of the coatings was measured by the samples rotated 72h at the 12 knots of simulating sailing speed. The results showed that the roughness of coatings changes from 0.2um to 3um, it does influenced slightly by the rotating test. Water contact angle of all coatings is about 100° before rotating test. It decreases to about 70° after the rotating test in seawater. Due to the increase of surface energy of the coatings, both the amount of diatom and bacteria on samples increases after rotating test in seawater.

scholarly journals Characterization and Control of the Wettability of Conducting Polymer Thin Films

2009 ◽  
Vol 1228 ◽  
Author(s):  
Jean H. Chang ◽  
Ian W Hunter
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Conducting Polymer ◽  
Water Contact Angle ◽  
Water Contact ◽  
Liquid Lenses ◽  
Polypyrrole Films ◽  
Electrochemically Deposited ◽  
Polypyrrole Film ◽  
And Control

AbstractThe wettability of electrochemically deposited conducting polymer films is highly dependent on several parameters including the deposition conditions, the dopant, and the roughness of the working electrode. To produce superhydrophobic surfaces, one must be able to control the micro and nanostructure of the film. In this study, a template-free method of producing superhydrophobic (water contact angle of 154°) polypyrrole films was demonstrated. The polypyrrole was doped with the low surface-energy heptadecafluorooctanesulfonic acid and had microstructures with nanometer-scale roughness. The microstructures served to increase the roughness of the film and amplify the hydrophobicity of the surface. It is also of interest to be able to dynamically adjust the wettability of a polypyrrole surface after deposition. Applications of this functionality include microfluidics, self-cleaning surfaces, liquid lenses, and smart textiles. By oxidizing or reducing a polypyrrole film, one can change the surface morphology as well as the chemical composition, and control the wettability of the surface. This study characterizes the electrochemically-induced changes in surface energy of polypyrrole. The relationship between applied voltage, charge transferred, surface roughness, and water contact angle was investigated. Upon reduction, the polypyrrole film was switched to a superhydrophilic state and the maximum change in contact angle was observed to be 154°. Surface wettability was found to be not fully reversible, with some hysteresis occurring after the first electrochemical cycle.

Sign in / Sign up

Export Citation Format

Share Document