Research on the Strengthen of Silicone Rubber

2013 ◽  
Vol 663 ◽  
pp. 377-380 ◽  
Author(s):  
Wen Juan Gu ◽  
Ying Li ◽  
Bang Gui He

A new kind of microsphere filler was synthesized with octyltrimethoxysilane (WD13) and tetraethoxysilane (TEOS) by sol-gel method. The morphology of the filler was measured by TEM. The so synthesized spheres were added into the silicone rubber. Both the strain-stress and the water contact angle of the silicone rubber were researched. The results showed that both the mechanical property and the hydrophobic performance of the composite were improved compared with the blank specimen. The possible strengthen mechanism of the filler was discussed. The neotype silica sphere researched in this paper could react with the silicone rubber chains which perfects the vulcanization of the silicone rubber. This kind of sphere filler exhibits many merits for usage as filler.

Soft Matter ◽  
2021 ◽  
Author(s):  
Jixi Zhang ◽  
Ligui Zhang ◽  
Xiao Gong

In this work, we prepare a PDMS-SiO2-PDA@fabric with high water contact angle (WCA=155o). Combining dopamine self-polymerization and sol-gel method, SiO2 is in situ grown on a PDA-modified fabric surface to...


2017 ◽  
Vol 7 ◽  
pp. 184798041770279 ◽  
Author(s):  
Baojiang Liu ◽  
Taizhou Tian ◽  
Jinlong Yao ◽  
Changgen Huang ◽  
Wenjun Tang ◽  
...  

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.


Proceedings ◽  
2018 ◽  
Vol 2 (17) ◽  
pp. 1155 ◽  
Author(s):  
Reza Peymanfar ◽  
Farzaneh Azadi ◽  
Yousef Yassi

Recently, using microwave devices that emit electromagnetic waves and enhance the convenience of life have increased; however, they can be harmful to the environment. In this study, CuFe2O4 nanoparticles were prepared through the conventional sol-gel procedure and then were characterized by X-ray powder diffraction (XRD), vibrating sample magnetometer (VSM), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), and vector network analyzer (VNA) using S parameters. Results illustrated that pure crystal structure of magnetic nanoparticles has been synthesized by the sol-gel method with magnetic saturation (Ms) of 22 emu/g. Finally, CuFe2O4 nanoparticles were composited by silicone rubber to investigate its microwave absorption properties. Results showed that the CuFe2O4/silicone rubber nanocomposite absorbed more than 94.87% of the microwave irradiation at ku-band frequency with 1.7 mm thickness and the maximum reflection loss was −60.38 dB at 16.1 GHz. Magnetic and dielectric properties of the CuFe2O4 nanoparticles and silicone rubber polymeric matrix in the nanocomposite demonstrated desirable microwave absorption properties.


2007 ◽  
Vol 2007.15 (0) ◽  
pp. 121-122
Author(s):  
Naoyuki TAKAHASHI ◽  
Motofumi OHKI ◽  
Tatsuya ISHIBASHI

2014 ◽  
Vol 881-883 ◽  
pp. 986-989
Author(s):  
Fa Qiu Hou ◽  
Ning Qing ◽  
Yong Jun Chen

nano-SiO2 modified core-shell polyacrylate composite emulsion was synthesized by seeded semi-continuous starved pre-emulsion polymerization and sol-gel technique. The influence of 3-methacryloxypropyltrimethoxysilane(KH-570), tetraethoxysilane(TEOS) on the properties of emulsion and film were studied. The SiO2/silicone polyacrylate composite latex and the resultant films were characterized by fourier transform infrared spectroscopy(FT-IR), differential scanning calorimeter(DSC), thermogravimetric analysis(TGA), water contact angle goniometer (WCAG). The results showed that organic silicon and nano-SiO2 were effectively grafted to the polyacrylate molecular chain. We can observed there are two glass transition temperatures (Tg) in the DSC curve. The water contact angle (WCA) on the PAE film and SSPAE film separately attained 62.5°and 85.5°.


2011 ◽  
Vol 391-392 ◽  
pp. 505-510
Author(s):  
Yan Pang ◽  
Yao Chen ◽  
Qi Qiu ◽  
Fang Wang ◽  
Zhang Tao

Optically transparent hydrophobic inorganic-organic hybrid sols was obtained employing Tetraethylorthosilicate (TEOS), Methyltriethoxysilane (MTES), and Heptadecafluoro-1, 1, 2, 2-tetradecyl)trimethoxysilane (FAS), with nitric acid as catalyst. Hybrid coating was dip coated on glass slides. The results showed that the water contact angle of MTES modified SiO2 coating was only 105° . As the weight ratio FAS varied from 0 to 8 wt.%, the water contact angle reached as high as 116.5°. The coated glass presented transmittance of 92%, 2% higher than the non-coated ones. The increase in transmittance suggested an antireflective effect of the hybrid coating. With further SEM characterization of the surface morphology, we finally obtained the optimized optically transparent hydrophobic hybrid coating with the MTES/TEOS_as 1/1(molar ratio) and FAS as 2 wt.%.


2013 ◽  
Vol 423-426 ◽  
pp. 443-447 ◽  
Author(s):  
Wen Wen Dou ◽  
Yu Chao Niu ◽  
Xiang Ju Liu ◽  
Xiao Li Wang ◽  
Yong Xu

Antireflective coatings with stable hydrophobicity for solar tube were prepared via sol-gel method and hexamethyldisilazane (HMDS) treatment. The coatings have a high porosity, groove-like surface morphology and a big static water contact angle. As a result, the coatings exhibit high transmittance even in high humidity environments. The transmittance peak can reach up to 99.02% which increased by 7% compared with the substrate and the wavelength band increased by more than 5% is from 438nm to 1000nm. After prolonged exposure to strong ultraviolet (UV) irradiation, the static water contact angle of the HMDS treated antireflective coatings decreased very small from 102o to 98o. In addition, the low-temperature tests showed the contact angle did not decline even at-50°C. The results suggest that the coatings prepared in present paper have stable hydrophobic and antireflective performance in the environment of strong UV radiation and low temperature.


2018 ◽  
Vol 83 (7-8) ◽  
pp. 885-897
Author(s):  
Ugur Hulusi ◽  
Burcu Oktay ◽  
Atilla Gungor ◽  
Nilhan Kayaman-Apohan

In this paper, the preparation of hydrophobic and crosslinked poly- (vinyl alcohol)/silica organic?inorganic hybrid nanofibers via the sol?gel electrospinning method is reported. Silica was produced through the acetic acid catalyzed reaction of a silica precursor consisting of dimethyldimethoxysilane (DMDMOS), methyltrimethoxysilane (MTMS), tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane (FAS1313; Dynasylan? F 8261) and phenyltrimethoxysilane (PTMS; Dynasylan? 9165) in a 2-propanol?water mixture. Hybrid nanofibers were obtained by electrospinning the silica precursor and an aqueous PVA solution. Chemical, structural, thermal and surface analyses were conducted by Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy/energy-dispersive X-ray (SEM/EDX) and water contact angle (WCA) methods, respectively. The obtained hybrid nanofibers were insoluble in aqueous solution. SEM images displayed that highly crosslinked and porous structures were obtained and the average fiber diameters of poly(vinyl alcohol) (PVA)/silica nanocomposites were around 70 nm. A nanofiber surface with a water contact angle of 130? was achieved.


2000 ◽  
Vol 49 (2) ◽  
pp. 200-203 ◽  
Author(s):  
Takashi OGIHARA ◽  
Nobuo OGATA ◽  
Yuko SHIGEKURA ◽  
Yoshiaki SAKAMOTO ◽  
Norifumi NAGATA

Proceedings ◽  
2018 ◽  
Vol 2 (17) ◽  
pp. 5234
Author(s):  
Reza Peymanfar ◽  
Mitra Rahmanisaghieh ◽  
Arezoo Ghaffari ◽  
Yousef Yassi

In the last decade, spinel structures have been widely explored due to widespread applications in antibacterial nanocomposites, memory devices, catalysts, photocatalysts, high-frequency devices, and electromagnetic absorbing materials. In this study, BaFe2O4 spinel structures were synthesized through the sol–gel method using a low sintering temperature and were identified by vibrating sample magnetometer (VSM), X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FE-SEM), and vector network analyzer (VNA) analysis. Results showed that uniform and pure crystal structures of BaFe2O4 nanoparticles were prepared based on the sol–gel method. Finally, BaFe2O4 nanoparticles were blended by silicone rubber to characterize the microwave absorption properties of the nanocomposite at the ku-band frequency. According to the VNA results, the BaFe2O4/silicone rubber nanocomposite with 1.75 mm thickness absorbed more than 94.38% of microwave irradiation along the ku-band frequency and the maximum reflection loss of the BaFe2O4/silicone rubber nanocomposite was 51.67 dB at 16.1 GHz.


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