Estudio por espectroscopía infrarroja de la reacción de hidrólisis y policondensación del IEOS en presencia de PDMS

Velasco, M. J.; Rubio, Juan; Oteo, J. L.

doi:10.3989/cyv.2001.v40.i1.760

Cited by 9 publications

(9 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The presence of a band at 850 cm −1 in TEOS/polysiloxane-based materials has been proposed to arise from condensation between TEOS and PDMS molecules during gel formation. 53 A similar pattern was observed in the FTIR spectrum of T 90 P 10 .…”

Section: Characterization Of Structural Properties Of Ormosilssupporting

confidence: 59%

Deposition of organic−inorganic hybrid coatings over 316L surgical stainless steel and evaluation on vascular cells

et al. 2014

View full text Add to dashboard Cite

Surface coating of metallic materials using the sol-gel technique is a suitable approach to obtain hybrid materials with improved properties for biomedical applications. In this study, an AISI 316L stainless steel surface was coated with ormosils prepared from tetraethylsiloxane and 3-glycidoxypropyltrimethoxysilane or polydimethylsiloxane. The characterization of structural and surface properties was performed by several techniques. Surface microstructure, morphology, and energy are dependent on organosilane type and content. Chemical stability of coatings was investigated by static immersion tests in phosphate buffer solution at 37 °C, and silicon leaching after 21 days was found to be in the range of ∼200−300 μg L−1. Mechanical adhesion was found to be within 1.0 and 3.7 N cm−1. The interaction of the samples and materials in the cardiovascular environment was investigated through cellular behavior. Biological assays were performed with slides to avoid any cytotoxic effects on human endothelial cells (HUVEC) and rabbit arterial smooth muscle cells (RASM). No significant alterations were observed after 24 h in the viability of RASM and HUVEC cells exposed to different coatings. No increase of HUVEC or RASM migration was observed after 24 h as evaluated by transwell migration assay. The hybrid materials showed suitable properties for potential application as biomaterials in cardiovascular environment as well as for incorporation of bioactive species with the aim to prepare drug-eluting stents.

show abstract

Section: Characterization Of Structural Properties Of Ormosilssupporting

confidence: 59%

Deposition of organic−inorganic hybrid coatings over 316L surgical stainless steel and evaluation on vascular cells

et al. 2014

View full text Add to dashboard Cite

show abstract

“…First, the stretching band for ArC-C bond appears as a wide band near 1,450 cm -1 , instead of the two well defined bands of PI-DABA25 and PI-Allyl spectra, indicating changes in the chemical environment around the aromatic structure after silylation. However, the band at 1,200 cm -1 , presumably associated to symmetric deformation of Si-CH 3 , and intense bands near 850 and 740 cm -1 associated with stretching vibration of Si-C bond [26], appear in all spectra, while the stretching bands for Si-O bonds in Si-O-Si and Si-O-C units, were overlapped with the stretching vibration of C-F bonds near 1,100 cm -1 [27]. Only the band at 470 cm -1 associated to stretching vibration of O-Si-O bond appeared in the PI-Si spectrum, being representative of the change in the pendant structure after modification with DMES.…”

Section: Resultsmentioning

confidence: 97%

Polyimide-silica sol–gel membranes from a novel alkoxysilane functionalized polyimide: preparation, characterization and gas separation properties

Huertas

Marestin

Merçier

et al. 2014

J Sol-Gel Sci Technol

View full text Add to dashboard Cite

Novel polyimide-organosilicate hybrid films were prepared by sol-gel process from a novel functionalized polyimide with alkoxysilanes as pendant groups that increase the affinity between inorganic and organic phases. The synthesis of this functionalized polyimide was carried out by an esterification reaction of a copolyimide containing carboxylic acid groups with allyl alcohol and subsequent hydrosililation. Tetraethoxysilane was used as precursor of silica in different amounts to obtain hybrid membranes with a silica content of 5, 10 and 20 %. The polymers and hybrid membranes were structural, mechanical and thermally characterized. The 29 Si-NMR solid state spectroscopy confirmed that silica was covalently bonded to the polyimide. SEM pictures showed a good dispersion of the silica particles and an amorphous morphology was observed by WAXS. DSC analyses revealed an increase in rigidity with the increase in silica content. The mechanical strength of the hybrid membranes decreased with the silica amount, exhibiting a brittle behavior. The evaluation of the gas permeation properties revealed that the film with the lowest silica content showed the highest permeability coefficients for O 2 , N 2 , CH 4 , and CO 2 with 34, 8, 6, and 128 barrers respectively, while all hybrid membranes showed similar permselectivities around 4 and 22 for O 2 /N 2 and CO 2 /CH 4 respectively. The fractional free volume of hybrid membranes determined by positron annihilation lifetime spectroscopy followed the same trend that permeability coefficients, confirming that the gas transport properties are mainly governed by the free volume elements.

show abstract

“…There are two absorption bands located at 2960 and 2905 cm -1 attributed to the υ a and υ s of C-H in the -CH 3 group of PDMS, respectively. [25,26]. The absorption bands due to υ a and υ s of Si-O in Si-O-Si bonding of inorganic network appears as a shoulder at 1190 cm -1 and as an intense wide band at 1080 cm -1 , respectively.…”

Section: Resultsmentioning

confidence: 99%

Modulación del carácter hidrofílico e influencia sobre la biocompatibilidad de híbridos base poliuretano-siloxano

Jiménez-Gallegos¹,

Téllez-Jurado²,

Rodríguez‐Lorenzo³

et al. 2011

Bol. Soc. Esp. Ceram. Vidr.

View full text Add to dashboard Cite

Organic-inorganic hybrid materials are known for their outstanding chemical and physical properties. Although some studies have been published regarding the use of hybrids for biomedical applications, relationship between hydrophilic character and biodegradation, bioactivity and biocompatibility has not been studied yet. The sol-gel method has been chosen for the manufacturing of siloxane-polyurethane hybrids for the exceptional potential of the method to obtain nanostructured materials. The effect of the amount of the urethane oligomer (OPU) on the structure, hydrophilic character, degradability, bioactivity and citotoxicity was investigated. Gelling time of these hybrids increases linearly with the decrease on the Siloxane/OPU ratio up to an 80/20 value. Hydrophilic character of the hybrids can be modulated and affects dramatically the degradation rate of the specimens. A hybrid with a 50/50 Siloxane/OPU ratio displayed an appropriate degradation rate, bioactivity and lack of cell toxicity that makes this material a candidate for further studies for applications in bone regeneration.Keywords: Sol-gel process; Biomedical applications; Hybrid Materials; Bioactivity; Polyurethane. Modulación del carácter hidrofílico e influencia sobre la biocompatibilidad de híbridos base poliuretano-siloxanoLos materiales híbridos Orgánico-Inorgánico son conocidos por sus excepcionales propiedades químicas y físicas. Aunque se han publicado algunos estudios respecto al uso de híbridos para aplicaciones biomédicas, aun faltan estudios que determinen la relación que existe entre el carácter hidrofílico de estos materiales y las propiedades que les permiten ser utilizados como biomateriales: degradación, bioactividad y biocompatibilidad. El método sol-gel se ha escogido para la fabricación de híbridos debido a la posibilidad de obtener materiales nanoestructurados que comprenden un componente orgánico y un inorgánico. Se investigó el efecto de la cantidad del olígomero de uretano (OPU) sobre la estructura, el carácter hidrofílico, la degradabilidad, la bioactividad y la citotoxicidad. El tiempo de gelificación de estos híbridos incrementa linealmente con la disminución en la relación Siloxano/OPU hasta un valor de 80/20. El carácter hidrofílico de los híbridos se puede modular y afectar considerablemente la velocidad de degradación de las muestras. Un híbrido con una relación 50/50 Siloxane/OPU muestra una velocidad de degradación, una bioactividad y falta de toxicidad que hacen a este material un candidato para futuros estudios para aplicaciones en regeneración ósea.

show abstract

Estudio por espectroscopía infrarroja de la reacción de hidrólisis y policondensación del IEOS en presencia de PDMS

Cited by 9 publications

References 13 publications

Deposition of organic−inorganic hybrid coatings over 316L surgical stainless steel and evaluation on vascular cells

Deposition of organic−inorganic hybrid coatings over 316L surgical stainless steel and evaluation on vascular cells

Polyimide-silica sol–gel membranes from a novel alkoxysilane functionalized polyimide: preparation, characterization and gas separation properties

Modulación del carácter hidrofílico e influencia sobre la biocompatibilidad de híbridos base poliuretano-siloxano

Contact Info

Product

Resources

About