Influence of Hybrid Sol-Gel Crosslinker on Self-Healing Properties for Multifunctional Coatings

Self-healing polymers are a new class of material that has recently received a lot of attention because of the lifespan improvement it could bring to multiple applications. One of the major challenges is to obtain multifunctional materials which can self-heal and exhibit other interesting properties such as protection against corrosion. In this paper, the effect of the incorporation of an aminosilane on the properties of a self-healing organic polymer containing disulfide bond is studied on films and coatings for aluminium AA2024-T3 using simple one step in situ synthesis. Hybrid coatings with enhanced anticorrosion properties measured by EIS were obtained thanks to the formation of a protective oxide interface layer, while exhibiting wound closure after exposition at 75 °C. The thermal, mechanical and rheological properties of the films with different aminosilane amounts were characterized in order to understand the influence of the slight presence of the inorganic network. Stiffer and reprocessable hybrid films were obtained, capable to recover their mechanical properties after healing. The nanocomposite structure, confirmed by TEM, had a positive effect on the self-healing and stress relaxation properties. These results highlight the potential of sol-gel chemistry to obtain efficient anticorrosion and self-healing coatings.

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UV-curable fluorine-containing hybrid coatings via thiol-ene “click” reaction and an in situ sol–gel method

Polymer Bulletin ◽

10.1007/s00289-012-0871-2 ◽

2012 ◽

Vol 70 (3) ◽

pp. 1037-1048 ◽

Cited By ~ 10

Author(s):

Emrah Çakmakçı ◽

Yusuf Mülazim ◽

Memet Vezir Kahraman

Keyword(s):

Click Reaction ◽

Sol Gel ◽

Hybrid Coatings ◽

Uv Curable ◽

Gel Method ◽

Sol Gel Method

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The Nanocrystallinity Enhancement of Sol-Gel Derived TiO2 Nanoparticles by Pre-Hydrothermal Treatment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.715 ◽

2011 ◽

Vol 415-417 ◽

pp. 715-719 ◽

Cited By ~ 1

Author(s):

Akhmad Herman Yuwono ◽

Yu Zhang ◽

John Wang

Keyword(s):

Thin Film ◽

Hydrothermal Treatment ◽

Polymethyl Methacrylate ◽

Sol Gel ◽

Nanocomposite Thin Film ◽

New Class ◽

Sol Gel Process ◽

Optoelectronic Applications ◽

Processing Techniques

Nanocomposite thin film containing TiO2nanoparticles in polymethyl methacrylate (PMMA) is a new class of potential materials for optoelectronic applications. Among the various processing techniques for these nanocomposites, in situ sol−gel process is well known to be versatile as it enables control of the inorganic-organic interaction at various molecular, nanometer and micrometer scales. However, the resulting TiO2phase is largely amorphous, as a consequence of the relatively low processing temperatures. Therefore, the current research is aimed at enhancing the nanocrystallinity of TiO2nanoparticles in nanocomposites. For this purpose, pre-hydrothermal treatment was carried on the inorganic sols. The nanocrystallinity degree of the resulting TiO2nanoparticles was studied by XRD and FTIR. The studies showed that the nanocrystallinity of TiO2nanoparticles synthesized from the inorganic sol can be enhanced significantly by the pre-hydrothermal treatment, as a result of the completion of hydrolysis stage during sol-gel process.

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Enzymatic Template Synthesis of Polyphenol

MRS Proceedings ◽

10.1557/proc-600-255 ◽

1999 ◽

Vol 600 ◽

Cited By ~ 2

Author(s):

Ferdinando F. Bruno ◽

Ramaswamy Nagarajan ◽

Jena S. Sidhartha ◽

Ke Yang ◽

Jayant Kumar ◽

...

Keyword(s):

Water Solubility ◽

Sol Gel ◽

Water Soluble ◽

Third Order ◽

High Molecular Weight Complex ◽

New Class ◽

Vis Spectroscopy ◽

Electrical Conductivities ◽

One Step ◽

High Degree

AbstractAn alternative, biocatalytic approach for the synthesis of a new class of water soluble and processable polyphenols is presented. In this approach, the enzyme horseradish peroxidase (HRP) is used to polymerize phenol in the presence of an ionic template. The template serves as a surfactant that can both emulsify the phenol monomer and growing polyphenol chains and provide water solubility of the final polyphenol/template complex. This approach is a simple, one step synthesis where the reaction conditions are remarkably mild and environmentally compatible. The final product is a water soluble, high molecular weight complex of polyphenol and the template used. The approach is also very versatile as numerous templates may be used to build in specific functionalities to the final polyphenol complex. Polystyrene sulfonates (SPS), lignin sulfonate and dodecyl benzene sulfonates (micelles) are the templates investigated in this study. Thermal analysis and UV-Vis spectroscopy shows that these complexes have exceptional thermal stability and a high degree of backbone conjugation. Electrical conductivities on the order of 10−5 S/cm and third order nonlinear optical susceptibilities (χ(3)) of 10−12 esu are also observed. In the case of the SPS template, under certain conditions, a sol gel complex may be formed. This enzymatic approach offers interesting opportunities in the synthesis and functionalization of a new class of processable polyphenolic materials.

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Synthesis and Characterization of Covalent Organic Polymer

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.701.270 ◽

2016 ◽

Vol 701 ◽

pp. 270-274

Author(s):

Siew Pei Lee ◽

Nurhayati Mellon ◽

Tuck Khein Lau ◽

Azmi Mohd Shariff ◽

Jean Marc Leveque

Keyword(s):

Low Cost ◽

Lower Surface ◽

Organic Polymer ◽

Gravimetric Analysis ◽

New Class ◽

Degradation Temperature ◽

Infra Red ◽

One Step ◽

The Difference

Development of covalent organic polymer (COP) is a potential new class of adsorbent for gas separation due to their good hydrothermal stability, chemical tuning flexibility and low cost. COP-1 was prepared via one-step polycondensation of cyanuric chloride and piperazine under catalyst free and N2 atmosphere condition. The properties of COP-1 were characterized using several analytical methods such as Fourier Transform Infra-Red (FTIR), solid Nuclear Magnetic Resonance (s-NMR), Thermal gravimetric analysis (TGA) and N2 adsorption and desorption measurement. The C-N bond of COP-1 which has non-rigid framework was successfully linked in this study. It is found that COP-1 has low thermal degradation temperature i.e. 483 K. As compared to literature, lower surface area (75.5 m2/g) and slightly large pore size (8 nm) are noticed. The difference of physical properties of COP-1 synthesized between in this study and literature revealed the challenge of reproducibility for COP-1.

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Growth and Dissolution of Protective Oxide Films on Titanium: an in-Situ Neutron Reflectivity Study

MRS Proceedings ◽

10.1557/proc-376-247 ◽

1994 ◽

Vol 376 ◽

Cited By ~ 3

Author(s):

D.G. Wlesler ◽

C.F. Majkrzak

Keyword(s):

Silicon Crystal ◽

Electrolyte Composition ◽

Neutron Reflectometry ◽

Neutron Reflectivity ◽

Self Healing ◽

Protective Oxide ◽

Structure And Morphology ◽

Titanium Thin Film ◽

Protective Oxide Film

ABSTRACTThe structure and morphology of titanium thin film electrodes have been investigated by neutron reflectometry. This technique yields a detailed depth profile of the scattering density, which is used to determine hydrogen and oxygen concentration profiles within the electrode. By depositing the electrode on a thick silicon crystal window, we are able to monitor the growth and dissolution of the protective oxide film covering the titanium as a function of time, electrode potential, and electrolyte composition. We find that, in 0.1 N sulfuric acid, the oxide dissolves at 0.7 A/h and is self-healing, meaning that as the oxide dissolves the metal underneath is oxidized to maintain a protective barrier. In contrast, when a -2 V cathodic bias is applied to a passive film, the oxide thins with no compensating oxide growth underneath, and the film undergoes electrochemical breakdown.

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Hybrid Sol–Gel Superhydrophobic Coatings Based on Alkyl Silane-Modified Nanosilica

Polymers ◽

10.3390/polym13040539 ◽

2021 ◽

Vol 13 (4) ◽

pp. 539

Author(s):

Dafna Heiman-Burstein ◽

Anna Dotan ◽

Hanna Dodiuk ◽

Samuel Kenig

Keyword(s):

Contact Angle ◽

Sol Gel ◽

Alkyl Substituent ◽

Hybrid Coatings ◽

Sliding Angle ◽

Random Surface ◽

Water Contact ◽

Superhydrophobic Coatings ◽

Long Chain

Hybrid sol–gel superhydrophobic coatings based on alkyl silane-modified nanosilica were synthesized and studied. The hybrid coatings were synthesized using the classic Stöber process for producing hydrophilic silica nanoparticles (NPs) modified by the in-situ addition of long-chain alkyl silanes co-precursors in addition to the common tetraethyl orthosilicate (TEOS). It was demonstrated that the long-chain alkyl substituent silane induced a steric hindrance effect, slowing the alkylsilane self-condensation and allowing for the condensation of the TEOS to produce the silica NPs. Hence, following the formation of the silica NPs the alkylsilane reacted with the silica’s hydroxyls to yield hybrid alkyl-modified silica NPs having superhydrophobic (SH) attributes. The resulting SH coatings were characterized by contact angle goniometry, demonstrating a more than 150° water contact angle, a water sliding angle of less than 5°, and a transmittance of more than 90%. Confocal microscopy was used to analyze the micro random surface morphology of the SH surface and to indicate the parameters related to superhydrophobicity. It was found that a SH coating could be obtained when the alkyl length exceeded ten carbons, exhibiting a raspberry-like hierarchical morphology.

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Bi-hybrid coatings: polyaniline-montmorillonite filler in organic-inorganic polymer matrix

Chemical Papers ◽

10.2478/s11696-012-0299-z ◽

2013 ◽

Vol 67 (8) ◽

Cited By ~ 6

Author(s):

Milena Špírková ◽

Patrycja Bober ◽

Jiří Kotek ◽

Jaroslav Stejskal

Keyword(s):

Polymer Matrix ◽

Propylene Oxide ◽

Sol Gel ◽

Reaction System ◽

Tensile Tests ◽

Polymeric Matrix ◽

Inorganic Polymer ◽

Hybrid Coatings ◽

Surface Modified

AbstractA bi-hybrid composite is represented by an organic-inorganic (O-I) filler dispersed in an O-I matrix. Polyaniline-montmorillonite, as a nanocomposite filler, was synthesised by two independent processes: (1) montmorillonite was surface-modified with a conducting polymer, polyaniline, during the in-situ oxidation of aniline or (2) montmorillonite was pre-treated with aniline, then the aniline was polymerised and the polyaniline subsequently produced penetrated the montmorillonite structure. The organic-inorganic polymer matrix was formed in two independent steps: (1) inorganic building units were formed in situ by the sol-gel process, (2) followed by organic polymeric matrix formation by polyaddition reactions of epoxy groups with amines. Polyaniline-montmorillonite filler was added to the reaction system between these two steps, i.e. when the inorganic structures of the O-I matrix have already been formed but prior to formation of the organic polymeric matrix. Two different O-I matrices were prepared from functionalised organosilicon precursors and oligomeric amines. 3-[(Glycidyloxy)propyl]trimethoxysilane reacted with α,ω-oligo(propylene oxide) diamine and diethoxy[3-(glycidyloxy)propyl]-methylsilane reacted with α,ω-oligo(propylene oxide) triamine. The resulting bi-hybrid coatings, the O-I filler dispersed in the O-I matrix, were characterised by atomic-force and optical microscopies, and also by tensile tests. The filler composition affected both the mechanical and surface properties of the coatings.

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