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.

Colloidal characteristics of gelatin-treated clay: Intercalation, stability, wettability, and rheological properties

2021 ◽  
Vol 29 (9_suppl) ◽  
pp. S1361-S1370
Author(s):  
Xuwu Luo ◽  
Guancheng Jiang ◽  
Xinliang Li ◽  
Lili Yang
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Rheological Properties ◽  
Water Contact Angle ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Water Contact ◽  
Ζ Potential ◽  
And Behavior ◽  
Clay Intercalation

In this paper, sodium montmorillonite was modified with gelatin of different concentrations, and various colloidal characteristics of the gelatin-treated clays were measured and analyzed in detail. First, the influence of gelatin on the interlayer space of Mt layers was investigated by X-ray diffraction analysis. Moreover, the aggregation of Mt particles was examined using a combination of electron microscopy and particle size distribution experiments, while the variation of the electrical property of Mt was measured using ζ potential test. Gelatin of different concentrations can increase the particle size of Mt in different degrees. The addition of 4% gelatin could improve the ζ potential of Mt from −30.65 to −15.55 mV. The wettability change of modified Mt induced by the adsorption of gelatin was followed by measurements of water contact angle and observations of the morphology of Mt/gelatin membrane through SEM images. 4% gelatin could improve the water contact angle of Mt to 81.3°. Finally, the rheological properties of Mt/gelatin dispersion including shear viscosity and shear stress were measured using a stress-controlled rheometer. All of the results were consistent by showing that the overall colloidal characteristics and behavior of the gelatin-treated Mt strongly varied depending on the gelatin concentration used in the modification process. These results can provide a deep and comprehensive understanding of the colloidal properties of clay/gelatin systems and give important guidance for the performance design and improvement of Mt/gelatin composite materials. Furthermore, this study can also be expanded the application of gelatin and its composites to other fields.

Top Layer Coating for Improving Superhydrophobic Property of Latex Cup

2017 ◽  
Vol 757 ◽  
pp. 52-56
Author(s):  
Sunisa Jindasuwan ◽  
Sitthisuntorn Supothina
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Field Test ◽  
Rubber Tree ◽  
Contact Angles ◽  
Economic Plant ◽  
Free Energy Surface ◽  
Immersion Method ◽  
Water Contact ◽  
Superhydrophobic Property

A latex cup is used to collect latex from a rubber tree which is an economic plant in Thailand. The fresh latex or crude rubber consists of organic compound and water which can wet and adhere to surface of the collecting cup. In this research, surface of the latex cup was treated with polymethylhydrogen siloxane-functionalized silica compound to improve hydrophobicity so that it could repel the dirt and latex, resulting in an anti-adhesion between the latex and the cup. Surface of the latex cup was etched with 10 % v/v hydrofluoric acid for 30 min before application of the siloxane coating which was performed by immersion in the solution, painting and spraying, respectively. The result revealed that the immersion method exhibited optimum property justified by high value of water contact angle, low surface free energy, surface roughness and the field test. At the optimum polymethylhydrogen siloxane : fumed silica ratio of 3 : 1 wt%, the treated sample had water contact angle of 139.24 ± 0.78 degrees and possessed surface energy of 1.07 mJ/m2. The field test conducted in the rubber field in Trang province revealed good durability of the coating. The water contact angles were 132.15 ± 2.05 and 129.20 ± 2.34 degrees after 2 weeks and 1 month, respectively, of the field service.

Synthesis of water-based cationic polyacrylate copolymer emulsion by RAFT polymerization and its application as an inkjet printing agent

2020 ◽  
Vol 49 (5) ◽  
pp. 401-408
Author(s):  
Haojia Su ◽  
Zhengchun Cai ◽  
Zhengwei lv ◽  
Yongkang Chen ◽  
Yongxin Ji
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Epoxy Resin ◽  
Water Contact Angle ◽  
Inkjet Printing ◽  
Raft Polymerization ◽  
Printing Industry ◽  
Water Contact ◽  
Content Type ◽  
Ethyl Methacrylate

Purpose In this work, the authors used reversible addition-fragmentation transfer (RAFT) polymerization to develop a new cationic acrylate modified epoxy resin emulsion for water-borne inkjet which have the advantages of both polyacrylate and epoxy resin. The emulsion was successfully used in the canvas coating for inkjet printing. This paper aims to contribute to the development of novel cationic emulsions for inkjet printing industry. Design/methodology/approach In this work, the epoxy acrylate was synthesized from RAFT agent and epoxy resin firstly. Cationic macromolecular emulsifier was prepared by RAFT polymerization, using 2,2’-Azobisisobutyronitrile as initiator, 2-(dimethylamino)ethyl methacrylate and styrene as monomer, which was directly used to prepare the emulsion. The influences of the amount of 2-(dimethylamino)ethyl methacrylate on particle size, zeta potential and water contact angle were studied. Finally, the cationic emulsion was used to print images by inkjet printing. Findings The emulsion has the smallest particle size, the highest potential and the highest water contact angle when the DM content is 13 Wt.%. The transmission electron microscopy analysis reveals the latex particles is core-shell sphere with the diameters in the range 120–200 nm. The emulsion was successfully used in the canvas coating for inkjet printing. This work will contribute to the development of novel cationic emulsions for inkjet printing industry. Originality/value The emulsion was successfully used in the canvas coating for inkjet printing. This work will contribute to the development of novel cationic emulsions for inkjet printing industry.

scholarly journals Strength and Water-Repelling Properties of Cement Mortar Mixed with Water Repellents

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5407
Author(s):  
Hyeju Kang ◽  
Sukpyo Kang ◽  
Byoungky Lee
Keyword(s):  
Contact Angle ◽  
Compressive Strength ◽  
Water Contact Angle ◽  
Cement Mortar ◽  
Contact Angles ◽  
Water Repellent ◽  
Water Contact ◽  
Rapid Hardening ◽  
Before And After ◽  
Large Water

In this study, the compressive strength and water contact angle of mortar specimens prepared by mixing two types of water repellent with ordinary Portland cement (OPC) and rapid-hardening cement mortar were measured before and after surface abrasion. In addition, the hydration products and chemical bonding of cement mortar with the repellents were examined using X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (TG-DTA), and Fourier-transform infrared spectroscopy (FT-IR) to evaluate the performance of these cement mortar mixtures as repair materials. We found that the fast-hardening cement mortar mixture containing the oligomer water repellent showed the best performance with a high compressive strength and large water contact angle. With the oligomer water repellent, the rapid-hardening cement mortar mixture showed contact angles of 131° and 126° even after a 2 mm abrasion, thereby confirming that the water repellent secured hydrophobicity through strong bonding with the entire cement mortar as well as its surface. The compressive strengths were found to be 34.5 MPa at 3 h and 54.8 MPa at 28 days, confirming that hydration occurred well despite the addition of water repellent.

Water-Contact-Angle Studies of Fabrics Radiation-Grafted with Methylhydrogensiloxane

1977 ◽  
Vol 47 (2) ◽  
pp. 87-91 ◽  
Author(s):  
Shinko Nishide ◽  
Harumichi Shimizu
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Unit Area ◽  
Contact Angles ◽  
Radiation Grafting ◽  
Water Contact ◽  
Petroleum Solvent ◽  
Solvent Washing

The water-contact angles of the polymethylhydrogensiloxane (silicone)-grafted fabrics (wool, cotton, Vinylon, rayon, acetate, Tetoron, nylon, and silk) prepared by irradiation were measured and the results support the following conclusions: 1. For the same degree of grafting, the relation between the water-contact angles and the roughness factors (defined as the number of yarn crossover points per-unit-area) of various fabrics is linear. It is concluded that the surfaces of grafted fabrics are in the same state regardless of kinds of fabrics. 2. On fabrics of the same roughness the water-contact angles of grafted samples are greater by about 10° than those of the silicone-coated samples, which are padded with silicone, not irradiated, and heated. This fact can be explained by the hypothesis that the upheavals on the surface of a fabric are increased by radiation grafting. 3. By repeated washing with petroleum solvent, the water-contact angles of grafted fabrics decrease a few degrees after one washing and then do not change further even after repeated washing. This result suggests that the grafted silicone is “set” into a conformation which is not appreciably altered in spite of repeated solvent washing.

scholarly journals Experimental approach towards the water contact angle value on the biomaterial alloy Ti6Al4V

2015 ◽  
Vol 70 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Margarita Hierro-Oliva ◽  
Amparo Maria Gallardo-Moreno ◽  
Abraham Rodríguez-Cano ◽  
Jose Morales Bruque ◽  
Maria Luisa González-Martín
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Contact Angles ◽  
Ti6al4v Alloy ◽  
Surrounding Water ◽  
Water Contact ◽  
Large Dispersion ◽  
Biomaterial Surface ◽  
Average Water ◽  
Orthopedic Applications

AbstractIn the biomedical field, water contact angle is a useful gauge to follow how a biomaterial surface would interact with the surrounding water-like physiological environment. Ti6Al4V alloy is widely used in orthopedic applications. Nevertheless, the values of its water contact angle reported in the literature show a large dispersion, from 40° up 80°. However, in addition to the expected dependence of the surface wettability on preliminary treatments, the values of the water contact angle on the pristine Ti6Al4V alloy suffers from an important variability and lack of reproducibility. The present research pays attention to this difficulty and proposes a simple experimental procedure to ensure adequate contact angle reproducibility. Controlled passivation growth in mild underwater conditions of freshly polished disks, followed by ultrasonic washing, avoiding the rubbing of the surface, gives average water contact angles of 80° with very low standard deviations also among samples from the same batch.

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.

scholarly journals Fabrication of a Simultaneous Highly Transparent and Highly Hydrophobic Fibrous Films

2021 ◽  
Vol 11 (12) ◽  
pp. 5565
Author(s):  
Doo-Hyeb Youn ◽  
Kyu-Sung Lee ◽  
Sun-Kyu Jung ◽  
Mangu Kang
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Water Contact Angle ◽  
Electrospun Fiber ◽  
Contact Angles ◽  
Light Transmittance ◽  
Electrospun Fibers ◽  
Water Contact ◽  
Aligned Fibers ◽  
Highly Hydrophobic

This paper discusses the fabrication and characterization of electrospun nanofiber scaffolds made of polystyrene (PS). The scaffolds were characterized in terms of their basis material molecular weight, fiber diameter distribution, contact angles, contact angle hysteresis, and transmittance. We propose an aligned electrospun fiber scaffold using an alignment tool (alignment jig) for the fabrication of highly hydrophobic (θW > 125°) and highly transparent (T > 80.0%) films. We fabricated the alignment jig to align the electrospun fibers parallel to each other. The correlation between the water contact angles and surface roughness of the aligned electrospun fibers was investigated. We found that the water contact angle increased as the surface roughness was increased. Therefore, the hydrophobic properties of the aligned electrospun fibers were enhanced by increasing the surface roughness. With the change in the electrospinning mode to produce aligned fibers rather than randomly distributed fibers, the transmittance of the aligned electrospun fibers increased. The increase in the porous area, leading to better light transmittance in comparison to randomly distributed light scattering through the aligned electrospun fibers increased with the fibers. Through the above investigation of electrospinning parameters, we obtained the simultaneous transparent (>80%) and hydrophobic (θW > 140°) electrospun fiber scaffold. The aligned electrospun fibers of PS had a maximum transmittance of 91.8% at the electrospinning time of 10 s. The water contact angle (WCA) of the aligned electrospun fibers increased from 77° to 141° as the deposition time increased from 10 s to 40 s. The aligned fibers deposited at 40 s showed highly hydrophobic characteristics (θW > 140°).

scholarly journals Simple Preparation of Polydimethylsiloxane and Polyurethane Blend Film for Marine Antibiofouling Application

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2242
Author(s):  
Jirasuta Chungprempree ◽  
Sutep Charoenpongpool ◽  
Jitima Preechawong ◽  
Nithi Atthi ◽  
Manit Nithitanakul
Keyword(s):  
Contact Angle ◽  
Polymer Film ◽  
Water Contact Angle ◽  
Bonding Strength ◽  
Soft Lithography ◽  
Water Contact ◽  
Pdms Film ◽  
Lithography Process ◽  
Micro Patterning ◽  
Marine Industry

A key way to prevent undesirable fouling of any structure in the marine environment, without harming any microorganisms, is to use a polymer film with high hydrophobicity. The polymer film, which was simply prepared from a blend of hydrophobic polydimethylsiloxane elastomer and hydrophilic polyurethane, showed improved properties and economic viability for antifouling film for the marine industry. The field emission scanning electron microscope and energy dispersive X-ray spectrometer (FESEM and EDX) results from the polymer blend suggested a homogenous morphology and good distribution of the polyurethane disperse phase. The PDMS:PU blend (95:5) film gave a water contact angle of 103.4° ± 3.8° and the PDMS film gave a water contact angle of 109.5° ± 4.2°. Moreover, the PDMS:PU blend (95:5) film could also be modified with surface patterning by using soft lithography process to further increase the hydrophobicity. It was found that PDMS:PU blend (95:5) film with micro patterning from soft lithography process increased the contact angle to 128.8° ± 1.6°. The results from a field test in the Gulf of Thailand illustrated that the bonding strength between the barnacles and the PDMS:PU blend (95:5) film (0.07 MPa) were lower than the bonding strength between the barnacles and the carbon steel (1.16 MPa). The barnacles on the PDMS:PU blend (95:5) film were more easily removed from the surface. This indicated that the PDMS:PU blend (95:5) exhibited excellent antifouling properties and the results indicated that the PDMS:PU blend (95:5) film with micro patterning surface could be employed for antifouling application.

Applicability of photochemically generated pendant benzoyl peroxides in both “grafting from” and “grafting to” techniques

2013 ◽  
Vol 67 (1) ◽  
Author(s):  
Jaroslav Mosnáček ◽  
Ivan Lukáč ◽  
Monica Bertoldo ◽  
Francesco Ciardelli
Keyword(s):  
Contact Angle ◽  
Spectroscopic Analysis ◽  
Film Surface ◽  
Contact Angles ◽  
Surface Grafting ◽  
Copolymer Films ◽  
Styrene Copolymers ◽  
Infrared Spectroscopic Analysis ◽  
Methyl Metacrylate ◽  
Grafting From

AbstractMethyl methacrylate and styrene copolymers containing pendant benzil groups, such as 1-[4-(2-methacroyloxyethoxy)phenyl]-2-phenyl-1,2-ethanedione-co-methyl metacrylate (BzMA/MMA), 1-[4-(2-methacroyloxyethoxy)phenyl]-2-phenyl-1,2-ethanedione-co-styrene (BzMA/S), and 1-phenyl-2-(4-propenoylphenyl)-1,2-ethanedione-co-styrene (PCOCO/S), were prepared and used as precursors for photochemically generated pendant benzoyl peroxides. Decomposition of the pendant benzoyl peroxides was subsequently used in grafting processes. Either irradiation or a combination of irradiation with subsequent thermal treatment was adopted for grafting a thin layer of BzMA/MMA copolymer onto the surface of LDPE films. The grafting resulted in a significant decrease in contact angle of the film surface. The same activation strategy was successfully adopted to initiate the polymerisation of acrylic or methacrylic acids from the surface of styrene copolymer films containing the initiator precursor in the polymer side chains (BzMA/S and PCOCO/S). The successful surface grafting was proved by contact angles measurement as well as by infrared spectroscopic analysis.

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