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1.
采用甲基丙烯酸十三氟辛酯(TFM)改性氨基硅油(AS)制备氟化氨基硅油(FAS),并用其改性环氧树脂(EP)探究氨基硅油及氟化氨基硅油添加量对环氧涂层性能的影响。本文通过红外光谱对改性结果进行表征,通过柔韧性测试、画圈附着力测试、铅笔硬度测试、耐冲击测试、热失重测试、接触角测试、紫外加速老化实验和Tafel极化曲线测试,分别评价涂层的柔韧性、附着力、硬度、耐冲击性、耐热性、疏水性、耐候性和防腐性能,通过扫描电镜对涂层断面进行分析,并通过EDS对涂层进行表面元素分析。结果表明,氟添加量为15%制备氟化氨基硅油改性环氧树脂时,氟硅改性EP涂层相对于未改性EP涂层,硬度由2H提升至3H,附着力由2级提升至1级,柔韧性由1mm提升至0.5mm,耐冲击由45cm提升至50cm,热稳定性增强,接触角由70.5°提升至123°,耐紫外老化(432h)由3级提升至1级,Ecorr由-0.6187V正移至-0.1720V,Icorr由1.9858×10-8A/cm2减小至3.7125×10-10A/cm2。适量氟化氨基硅油的引入,显著提升了环氧涂层的机械性能、耐候性能和防腐性能。  相似文献   

2.
To enhance the surface hydrophobicity of epoxy polymers, a simple physical method for the simultaneous surface fluorination during curing of epoxy resins was proposed and evaluated. Curing of epoxy resins against a polytetrafluoroethylene (PTFE) mold gave rise to fluorinated epoxy polymer surfaces due to the anchorage of PTFE molecules on the epoxy polymer surface. The modified epoxy surfaces were characterized using contact‐angle measurements and X‐ray photoelectron spectroscopy (XPS). The fluorinated epoxy resin surfaces are highly hydrophobic, exhibiting contact angles of similar magnitude to that of the pristine PTFE film surface. The PTFE mold can be used repeatedly to give fluorinated epoxy surfaces with large contact angles. Aging and solvent extraction tests indicated that the fluorinated epoxy surfaces were very stable. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 296–304, 2000  相似文献   

3.
An epoxy/PTFE composite was prepared by curing the epoxy resin on the surface-modified PTFE film. Surface modification of PTFE films was carried out via argon plasma pretreatment, followed by UV-induced graft copolymerization with glycidyl methacrylate (GMA). The film composite achieved a 90°-peel adhesion strength above 15 N/cm. The strong adhesion of the epoxy resin to PTFE arose from the fact that the epoxide groups of the grafted GMA chains were cured into the epoxy resin matrix to give rise to a highly crosslinked interphase, as well as the fact that the GMA chains were covalently tethered on the PTFE film surface. Delamination of the composite resulted in cohesive failure inside the PTFE film and gave rise to an epoxy resin surface with a covalently-adhered fluoropolymer layer. The surface composition and microstructures of the GMA graft-copolymerized PTFE (GMA-g-PTFE) films and those of the delaminated epoxy resin and PTFE film surfaces were characterized by X-ray photoelectron spectroscopy (XPS), water contact angle and scanning electron microscope (SEM) measurements. The delaminated epoxy resin surfaces were highly hydrophobic, having water contact angles of about 140°C. The value is higher than that of the pristine PTFE film surface of about 110°. The epoxy resin samples obtained from delamination of the epoxy/GMA-g-PTFE composites showed a lower rate of moisture sorption. All the fluorinated epoxy resin surfaces exhibited rather good stability when subjected to the Level 1 hydrothermal reliability tests.  相似文献   

4.
A novel dicarboxyl-terminated poly(2,2,3,4,4,4-hexafluorobutyl acrylate) oligomer (CTHFA) was synthesized through metal-free anionic polymerization and hydrolysis reaction. Chemical structures of CTHFA were characterized by gel permeation chromatography and 1H NMR. Two types of CTHFA with different chain lengths were initially used as an efficient surface modifier to improve the surface properties of epoxy resin, at the content of CTHFA ranging between 0 and 8 wt%. We minimized the amounts of the CTHFA used to achieve a high hydrophobic surface that was not obviously affected by the thermal properties of the epoxy resin. Surface properties and surface composition of the designed fluorinated epoxy resin were investigated by the contact angle and X-ray photoelectron spectroscopy (XPS). Modified epoxy resin with 5 wt% CTHFA containing longer chain length showed excellent hydrophobic surface properties (a high water contact angle about 115° and low surface energy 14.12?mN/m2) while the modified epoxy resin with 5 wt% CTHFA containing shorter chain length did not. XPS analyses indicated that the 5 wt% of fluorinated CTHFA epoxy resin with long macromolecular-chain enhanced more fluorinated groups?? migration to the surface than the fluorinated CTHFA-modified epoxy resin with short macromolecular-chain at the same content. Moreover, thermal properties of CTHFA-modified epoxy resin were also investigated.  相似文献   

5.
Fluorine‐based amphiphobic coatings have been widely used in commercial textiles to provide water‐ and oil‐repelling abilities. However, few reports from the literature survey have discussed the surface structural effects of the coated substrate on amphiphobicity. In this research, various thickness amphiphobic coatings based on mixed epoxy, tetraethylorthosilicate, and a particular alkoxysilane with fluorinated side chains (F‐silane) were deposited on Grade 420 stainless steel plates. Film amphiphobicity is characterized by measuring the water and oil contact angles of the coating. Film morphology is examined using atomic force microscopy. The deposited films free of F‐silane are thinner than 150 nm. The films become thick at high F‐silane volume percentage with the surface cavities, ridges, and granules being masked out. On the addition of F‐silane, the water contact angle of the deposited films increases up to 105° and then reaches a plateau of ~ 107° with increasing F‐silane. In contrast, the oil contact angle increases up to 60° at first and then slowly declines with the F‐silane concentration. The total drop of oil contact angle by ~ 20° was attributed to the masking out of surface features on film thickening. This indicates that the surface oleophobicity depends on surface structures. Therefore, improving surface amphiphobicity correlates with creating more refined multiscale surface structures during the industrial manufacturing process of steel plate, prior to surface modification by F‐silane. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41003.  相似文献   

6.
Durable excellent hydrophobic surface on cellulose substrate was fabricated from the silica hydrosol functionalized with silane chemicals by a facile electrochemically assisted deposition technique. The silica hydrosol was synthesized using tetraethoxysilane (TEOS) as the precursor and sodium dodecylbenzene (SDBS) as the emulsifier under acidic conditions. The hydrophobic silane modifiers including octyltriethoxysiliane (OTES), dodecyltriethoxysiliane (DTES) and isooctyltriethoxysiliane (iso‐OTES) and the silane‐coupling agent γ‐mercaptopropyltriethoxysilane (MPTES) were used to dope the silica hydrosol for preparing durable hydrophobic cellulose surface. The cellulose surface modified with silane modifier iso‐OTES exhibited the best hydrophobicity with water contact angle of 162.3 ± 0.5° due to its non‐polar and hydrolytically stable of ? Si(C8H17) groups. The addition of silane‐coupling agent MPTES containing the ? SH group led to good durability of hydrophobicity with water contact angle of 130.0 ± 1.2° after 20 washing times. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42733.  相似文献   

7.
This paper reports the fabrication of a lotus-effect coating by grafting epoxy (EP) resin on the surface of microsilica and nanosilica, respectively, and subsequent spraying. The coating shows the same structure and capability as lotus leaves, and shows a static contact angle as large as 165° and a sliding angle as small as 2.5°. SEM analysis shows that the hydrophobic capability depends on the surface structure of the coatings. This method may be suited for processing large scale or irregular surfaces.  相似文献   

8.
分别用苯基三甲氧基硅烷(PTMS)和3-缩水甘油醚氧丙基三甲氧基硅烷(KH560)单体对环氧树脂进行了化学改性,通过红外(FT-IR)、核磁(1H NMR)对其化学结构进行了表征。以聚酰胺650为固化剂,用差示扫描量热仪(DSC)研究了固化物的固化动力学。此外还研究了涂膜的热失质量(TGA)、吸水率、附着力等性能。结果表明:苯基三甲氧基硅烷和3-缩水甘油醚氧丙基三甲氧基硅烷接枝上环氧树脂,与纯环氧树脂相比,改性后的树脂具有更好的热稳定性和更低的吸水率。改性环氧树脂固化后形成两面性质不同的涂层,与底材接触的涂层底面保留了环氧树脂原有的附着力,而涂层表面则具有高憎水性,起到防腐等作用。  相似文献   

9.
A super hydrophobic cotton fabric was successfully prepared by a facile dip‐coating method using a synthetic fluorine‐free and UV curable super hydrophobic coating solution without additional particles. The obtained cotton fabric exhibited super hydrophobic property with a water contact angle above 159.5° and sliding angle 7.5°. Moreover, the treated cotton fabric could retain its super hydrophobic performance even after abrasion and accelerated laundering, as well as for different kinds of corrosive liquids. The coated cotton fabric was used to make up a surface tension‐driven, gravity‐assisted, floating oil–water separation device with separation efficiency above 99%. Additionally, the oil–water separation efficiency of super hydrophobic cotton fabric always was above 98% after 30 recycle times for cyclohexane–water mixture. POLYM. ENG. SCI., 59:E452–E459, 2019. © 2019 Society of Plastics Engineers  相似文献   

10.
Summary: A fluorine containing hyperbranched polymer was synthesized by modifying an aromatic‐aliphatic hyperbranched polyester with a semifluorinated alcohol via a Mitsunobu reaction and was subsequently used as an additive in cationic photopolymerization of an epoxy resin. The remaining OH groups of the fluorinated hyperbranched polymer interact with the polymeric carbocation through a chain‐transfer mechanism inducing an increase in the final epoxy conversion. The fluorinated HBP induces modification of bulk and surface properties, with an increase in Tg and surface hydrophobicity already reached at very low concentration. The HBFP additive can, therefore, protect the coatings from aggressive solvents, increases hardness, and allows the preparation of a low energy surface coating.

Synthesis of fluorinated hyperbranched polyester.  相似文献   


11.
Fluorinated polyacrylates containing amino side chains (FACAs) were synthesized to improve the water repellency of waterborne epoxy resin. First, FACA was prepared by a two-step process. Then, a phase-inversion emulsion technique, taking FACA as the reactive surface additives, was employed to prepare waterborne epoxy resin. The effect of the fluorinated content and the length of the fluorine side chain on the surface, thermal, and bulk properties of the waterborne epoxy resin were investigated. It was observed that moderate increase of the fluorinated content or the length of the fluorine side chain improved the contact angle and thermal properties while the mechanical property was not deteriorated. A small amount of fluoride (0.07 wt %) in the EA-F1/3-1 sample can dramatically increase the water contact angle from 72.63° to 95.31° due to the strong tendency of the macromonomers to migrate toward the outmost layer, resulting in enrichment of fluorine atoms on the surface. X-ray photoelectron spectroscopy results revealed that for a given weight of the two macromonomers, F atomic concentration of the copolymer modified by longer fluorinated side chains was higher than that modified by short fluorinated side chains. From the present investigation, FACA successfully improved the surface property of waterborne epoxy resin and showed a prominent potential application in large-scale industrialization. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47091.  相似文献   

12.
Poly(p‐phenylene benzobisoxazole) (PBO) fiber with a smooth surface exhibits limited interfacial interaction with resin matrix. One of the effective strategies to improve the adhesion between the fiber and resin matrix is through surface modification of the fiber. In this study, we have proposed a novel surface treatment agent based on phosphoester cross‐linked castor oil (PCCO) for effective surface treatment of PBO fibers. The surface treatment agent was prepared by a simple cross‐linking reaction between hydroxy phosphorylated castor oil (PCO) and epoxy resin, with alcohol as the solvent at 65°C. Once the PBO fiber was treated with this agent, the interfacial adhesion between the PBO fiber and the epoxy resin could then be improved. Systematic analyses suggest that the surface treatment with (PCO + epoxy)/alcohol solution improves the interaction of the PBO fiber with the epoxy resin matrix. The PCCO coated onto the surface of PBO fiber acts as a coupling agent, improving the interfacial shear strength (IFSS) of the PBO fiber/epoxy resin composite. Results indicate a 156% increase in IFSS without compromising the mechanical properties of the fiber. POLYM. COMPOS., 37:1198–1205, 2016. © 2014 Society of Plastics Engineers  相似文献   

13.
Aniline/p‐phenylenediamine copolymer [poly(ANI‐cop‐PDA)] was prepared by chemical oxidative polymerization. FTIR and 1H‐NMR analysis indicate that the poly(ANI‐cop‐PDA) is oligomer with end‐capped amino groups, which can cure epoxy resin. The anticorrosion performance of carbon steel (CS) samples coated by epoxy resin coating cured with poly(ANI‐cop‐PDA) and epoxy resin coating cured with triethylenetetramine exposed to 5 wt % NaCl and 0.1 mol/L HCl aqueous solution is studied by the potentiodynamic polarization and electrochemical impedance spectroscopy. The results show that the CS coated by epoxy resin coating cured with poly (ANI‐cop‐PDA) has more excellent corrosion protection than that of epoxy resin coating cured with triethylenetetramine. Raman spectroscopy analysis indicates that the surface of CS coated by epoxy resin coating cured with poly(ANI‐cop‐PDA) forms passive layer, which is composed of α‐Fe2O3. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

14.
Nanocasting was used to develop epoxy/graphene composites (EGCs) as corrosion inhibitors with hydrophobic surfaces (HEGC). The contact angle of water droplets on a sample surface can be increased from ∼82° (epoxy surface) to ∼127° (hydrophobic epoxy and EGC). It should be noted that EGC coating was found to provide an excellent corrosion protection effect on cold-rolled steel (CRS) electrode. Enhancement of corrosion protection using EGC coatings could be attributed to the following three reasons: (1) epoxy could act as a physical barrier coating, (2) the hydrophobicity repelled the moisture and further reduced the water/corrosive media adsorption on the epoxy surface, preventing the underlying metals from corrosion attack, and (3) the well-dispersed graphene nanosheets (GNSs) embedded in HEGC matrix could prevent corrosion owing to a relatively higher aspect ratio than clay platelets, which enhances the oxygen barrier property of HEGC.  相似文献   

15.
Water repellent SiO2 particulate coatings were prepared by a one-step introduction of vinyl groups on the coating surface. Rough surface structure and low surface energy could be directly obtained. Vinyl functionalized SiO2 (vinyl-SiO2) spheres with average diameter of 500 nm were first synthesized by a sol–gel method in aqueous solution using vinyltriethoxysilane as the precursor. The multilayer SiO2 coating fabricated by dip-coating method was highly hydrophobic with a water contact angle of 145.7° ± 2.3°. The superhydrophobic SiO2 coating with a water contact angle up to 158° ± 1.7° was prepared by spraying an alcohol mixture suspension of the vinyl-SiO2 spheres on the glass substrate. In addition, the superhydrophobic SiO2 coating demonstrated good stability under the acidic condition. However, it lost its hydrophobicity above 200°C because of the oxidation and degradation of vinyl groups.  相似文献   

16.
In this research, a silicon additive was synthesized by reaction of the hydroxyl terminated poly-dimethyl siloxane (PDMS-OH) with 3-glycidoxy propyl tri-methoxy silane (TMS-epoxy). The synthesized silicon additive characterized and evaluated to use as a curing agent for preparing high-performance and impermeable epoxy resin for encapsulation of flexible optoelectronic devices such as thin film photovoltaics and polymer light-emitting diodes to protect them against water penetration and increase their lifespan. The synthesized additive was characterized by FTIR, NMR, and elemental analysis. Thermal properties of the UV curable resin were investigated by using DSC and DMTA. The prepared UV cure epoxy resin exhibited an appropriate melting temperature (56.19 °C). Contact angle test, SEM, and calcium test was used to investigate the properties of UV-cured coating resin. The water contact angle of the cured prepared resin film showed good hydrophobicity. The SEM results confirmed the uniformity of cured film and UV cure resin dispersion. Transparency and flexibility of the cured film to encapsulate the flexible light emitting diodes are acceptable. The permeability of cured film to water vapor was evaluated by calcium test, which shows the cured film suitability to encapsulate the FOLED. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48033.  相似文献   

17.
Photopolymerization processes are often used in industrial applications because of their solvent‐free formulations and various advantages over conventional thermal processes. Fluorinated monomers and oligomers yield coatings of great interest because of the peculiar characteristics of fluorine atoms: these coatings show hydrophobicity, chemical stability, weathering resistance, etc. Novel UV‐curable fluorinated epoxy acrylate oligomers were synthesized from 1H,1H‐perfluorohexan‐1‐ol, 1,6‐hexamethylene diisocyanate (HDI) and epoxy acrylate (EA). The HDI plays the role of a spacer group in the side chain between the EA backbone chain and the fluorinated segment. This new spacer containing a urethane moiety with long alkyl groups can exhibit a self‐organization effect through the formation of strong hydrogen bonding. This resulted in a stiffening of the whole HDI urethane–perfluoalkyl chain to form nanostructure surface segregation. The designed fluorinated EA with fluoroalkyl (C5F11) units in the side chain exhibited a contact angle of about 151°, which is in the superhydrophobic range. Copyright © 2010 Society of Chemical Industry  相似文献   

18.
A novel fluorinated biphenyl‐type epoxy resin (FBE) was synthesized by epoxidation of a fluorinated biphenyl‐type phenolic resin, which was prepared by the condensation of 3‐trifluoromethylphenol and 4,4′‐bismethoxymethylbiphenyl catalyzed in the presence of strong Lewis acid. Resin blends mixed by FBE with phenolic resin as curing agent showed low melt viscosity (1.3–2.5 Pa s) at 120–122°C. Experimental results indicated that the cured fluorinated epoxy resins possess good thermal stability with 5% weight loss under 409–415°C, high glass‐transition temperature of 139–151°C (determined by dynamic mechanical analysis), and outstanding mechanical properties with flexural strength of 117–121 MPa as well as tensile strength of 71–72 MPa. The thermally cured fluorinated biphenyl‐type epoxy resin also showed good electrical insulation properties with volume resistivity of 0.5–0.8 × 1017 Ω cm and surface resistivity of 0.8–4.6 × 1016 Ω. The measured dielectric constants at 1 MHz were in the range of 3.8–4.1 and the measured dielectric dissipation factors (tan δ) were in the range of 3.6–3.8 × 10?3. It was found that the fluorinated epoxy resins have improved dielectric properties, lower moisture adsorption, as well as better flame‐retardant properties compared with the corresponding commercial biphenyl‐type epoxy resins. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

19.
Here, we reported the preparation of hydrophobic mesh films by coating conductive polymers including polyaniline and polypyrrole (PPy) onto stainless steel grid through a simple electrodepositing process by combination with modification of hydrophobic materials. The hydrophobic mesh films can be used for continual separation of oils and organics from water with high selectivity. Furthermore, mesh film with reversible switching wettability from hydrophobicity to hydrophilicity can be obtained by electrodepositing of PPy in the presence of perfluorooctanesulfonate dopants at different electric potential, which makes it possible to prepare functional mesh materials with remotely controllable surface wettability for selective absorption and purification. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40759.  相似文献   

20.
This study reports on the deposition of a hydrophobic coating on polyurethane (PU)-based synthetic leather through a plasma polymerization method and investigates the hydrophobic behavior of the plasma-coated substrate. The silicon compound of hexamethyldisiloxane (HMDSO), inactive gas argon (Ar), and toluene were used to impart surface hydrophobicity to a PU-based substrate. Surface hydrophobicity was analyzed by water contact angle measurements. Surface hydrophobicity was increased by deposition of compositions of 100% HMDSO, 3:1 HMDSO/toluene, and 1:1 HMDSO/toluene. Optimum conditions of 40 W, 30 s plasma treatment resulted in essentially the same initial contact angle results of approximately 100° for all three treatment compositions. The initial water contact angle for untreated material was about 73°. A water droplet took 1800 s to spread out on the plasma-treated sample after it had been placed on the sample surface. An increase in plasma power also led to a decrease in contact angle, which may be attributed to oxidization of HMDSO during plasma deposition. XPS analysis showed that plasma polymerization of HMDSO/toluene compositions led to a significant increase in atomic percentage of Si compound responsible for the hydrophobic surface. The easy clean results for the treated and untreated PU-based synthetic leather samples clearly showed that the remaining stain on the plasma-polymerized sample was less than that of untreated sample. The plasma-formed coating was both hydrophobic and formed a physical barrier against water and stain.  相似文献   

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