Coatings of PDMS-modified epoxy via urethane linkage: Segmental correlation length, phase morphology, thermomechanical and surface behavior

Epoxy resins have been presenting a lot of scientific and technical interests and organic modified epoxy resins have recently receiving a great deal of attention. For obtaining the composite materials with good mechanical proprieties, a large variety of organic modification agents were used. For this study gluten and gelatin had been used as modifying agents thinking that their dispersion inside the polymer could increase the polymer biocompatibility. Equal amounts of the proteins were milled together and the obtained compound was used to form 1 to 5% weight ratios organic agents modified epoxy materials. To highlight the effect of these proteins in epoxy matrix mechanical tests as three-point bending and compression were performed.

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Adhesion and the Surface Behavior of the Silicone Elastomer RTV-142.

10.21236/ada163815 ◽

1985 ◽

Author(s):

R. S. Bretzlaff ◽

T. A. Freitab ◽

A. Y. Lee

Keyword(s):

Silicone Elastomer ◽

Surface Behavior

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Bottlebrush polymers in the melt and polyelectrolytes in solution share common structural features

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1916362117 ◽

2020 ◽

Vol 117 (10) ◽

pp. 5168-5175 ◽

Cited By ~ 4

Author(s):

Joel M. Sarapas ◽

Tyler B. Martin ◽

Alexandros Chremos ◽

Jack F. Douglas ◽

Kathryn L. Beers

Keyword(s):

Neutron Scattering ◽

Correlation Length ◽

Salt Concentration ◽

Polymer Concentration ◽

Structural Features ◽

Peak Position ◽

Correlation Peak ◽

Grafting Density ◽

Scattering Measurements ◽

Polyelectrolyte Solutions

Uncharged bottlebrush polymer melts and highly charged polyelectrolytes in solution exhibit correlation peaks in scattering measurements and simulations. Given the striking superficial similarities of these scattering features, there may be a deeper structural interrelationship in these chemically different classes of materials. Correspondingly, we constructed a library of isotopically labeled bottlebrush molecules and measured the bottlebrush correlation peak position q*=2π/ξ by neutron scattering and in simulations. We find that the correlation length scales with the backbone concentration, ξ∼cBB−0.47, in striking accord with the scaling of ξ with polymer concentration cP in semidilute polyelectrolyte solutions (ξ∼cP−1/2). The bottlebrush correlation peak broadens with decreasing grafting density, similar to increasing salt concentration in polyelectrolyte solutions. ξ also scales with sidechain length to a power in the range of 0.35–0.44, suggesting that the sidechains are relatively collapsed in comparison to the bristlelike configurations often imagined for bottlebrush polymers.

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Dynamical correlation length near the chiral critical point

The European Physical Journal C ◽

10.1140/epjcd/s2003-03-617-y ◽

2003 ◽

Vol 33 (S1) ◽

pp. s627-s629 ◽

Cited By ~ 3

Author(s):

Kerstin Paech

Keyword(s):

Critical Point ◽

Correlation Length ◽

Dynamical Correlation

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Hydrophobic Modification of Graphene Oxide and Its Effect on the Corrosion Resistance of Silicone-Modified Epoxy Resin

Metals ◽

10.3390/met11010089 ◽

2021 ◽

Vol 11 (1) ◽

pp. 89

Author(s):

Wei Yuan ◽

Qian Hu ◽

Jiao Zhang ◽

Feng Huang ◽

Jing Liu

Keyword(s):

Contact Angle ◽

Corrosion Resistance ◽

Graphene Oxide ◽

Physical Properties ◽

Epoxy Resin ◽

Electrochemical Impedance ◽

Salt Spray ◽

X Ray ◽

Modified Graphene Oxide ◽

Modified Epoxy

This study modified graphene oxide (GO) with hydrophilic octadecylamine (ODA) via covalent bonding to improve its dispersion in silicone-modified epoxy resin (SMER) coatings. The structural and physical properties of ODA-GO were characterized by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle tests. The ODA-GO composite materials were added to SMER coatings by physical mixing. FE-SEM, water absorption, and contact angle tests were used to evaluate the physical properties of the ODA-GO/SMER coatings, while salt spray, electrochemical impedance spectroscopy (EIS), and scanning Kelvin probe (SKP) methods were used to test the anticorrosive performance of ODA-GO/SMER composite coatings on Q235 steel substrates. It was found that ODA was successfully grafted onto the surfaces of GO. The resulting ODA-GO material exhibited good hydrophobicity and dispersion in SMER coatings. The anticorrosive properties of the ODA-GO/SMER coatings were significantly improved due to the increased interfacial adhesion between the nanosheets and SMER, lengthening of the corrosive solution diffusion path, and increased cathodic peeling resistance. The 1 wt.% ODA-GO/SMER coating provided the best corrosion resistance than SMER coatings with other amounts of ODA-GO (including no addition). After immersion in 3.5 wt.% NaCl solution for 28 days, the low-frequency end impedance value of the 1 wt.% ODA-GO/SMER coating remained high, at 6.2 × 108 Ω·cm2.

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