Physicochemical Characterization of Novel Chitosan-Soy Protein/ TEOS Porous Hybrids for Tissue Engineering Applications

In this paper we report a new type of cross-linked porous structure based on a chitosansoy protein blend system developed by means of combining a sol-gel process with the freeze-drying technique. The final structure was investigated by Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR), contact angle measurements and the morphology by scanning electron microscopy (SEM). The water uptake capability and the weight loss were measured up to 14 days and their mechanical properties were assessed with compression tests. Results showed that the addition of tetraethyl orthosilicate (TEOS) to the chitosan-soy protein blend system provide specific interactions at the interface between the two polymers allowing to tailor the size and distribution as well as the degradation rate of the hybrids. Finally, TEOS incorporation induces an increase of the surface energy that influences the final physicochemical properties of the materials.

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Effect of Increasing Polyvinyl Alcohol Content on the Porous Structure and Mechanical Properties of Sol-Gel Derived Hybrids Foams

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.361-363.555 ◽

2007 ◽

Vol 361-363 ◽

pp. 555-558 ◽

Cited By ~ 2

Author(s):

Agda Aline Rocha de Oliveira ◽

R.L. Oréfice ◽

Herman S. Mansur ◽

Marivalda Pereira

Keyword(s):

Mechanical Properties ◽

Polyvinyl Alcohol ◽

Bioactive Glass ◽

Structural Characteristics ◽

Sol Gel ◽

Acetate Solution ◽

Compression Tests ◽

Sol Gel Process ◽

Hybrid Foams

Bioactive glass/polymer hybrids are promising materials for biomedical applications because they combine the bioactivity of these bioceramics with the flexibility of polymers. In previous work hybrid foams with 80% bioactive glass and 20% polyvinyl alcohol (PVA) were prepared by the sol-gel process for application as scaffold for bone tissue engineering. In this work it was evaluated the effect of increasing the PVA content of the hybrids on structural characteristics and mechanical properties of hybrid foams produced by this method. The hybrids were prepared with inorganic phase composition of 70%SiO2-30%CaO and PVA fractions of 20 to 60% by the sol-gel method. The structural and mechanical characterization of the obtained foams was done by FTIR, SEM, Helium Picnometry, and compression tests. To reduce the acidic character of the hybrids due to the catalysts added, different neutralization solutions were tested. The immersion of hybrids in a calcium acetate solution was the most adequate neutralization method, avoiding calcium loss while maintaining pH nearly 7,0 and low PVA loss. The foams presented porosity of 60-85% and pore diameters of 100-500μm with interconnected structure. The pore structure varied with the polymer content in the hybrid. The compression tests showed that an increase of PVA fraction in the hybrids improved their mechanical properties.

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Organic–inorganic sol-gel thick films for humidity barriers

Journal of Materials Research ◽

10.1557/jmr.2008.0283 ◽

2008 ◽

Vol 23 (8) ◽

pp. 2084-2090 ◽

Cited By ~ 9

Author(s):

Andrei Jitianu ◽

Glenn Amatucci ◽

Lisa C. Klein

Keyword(s):

Contact Angle ◽

Thick Films ◽

Sol Gel ◽

Attenuated Total Reflection ◽

Inorganic Materials ◽

Angle Measurements ◽

Glass Slides ◽

Contact Angle Measurements ◽

Sol Gel Process ◽

Poly Ethylene

Hybrid thick films were deposited on Surlyn, a copolymer of poly(ethylene- co-methacrylic acid) and a common adhesion film for metal surfaces. Hybrid organic–inorganic materials were prepared by a sol-gel process. Methyltriethoxysilane (MTES) with tetraethoxysilane (TEOS), phenyltriethoxysilane (PhTES) with TEOS, and methyltrimethoxysilane (MTMS) with tetramethoxysilane (TMOS) were investigated. The inorganic component was selected to form the network for the film, while the organic component was selected to repel water and fill porosity. The films were deposited on Surlyn and on glass slides. The properties of the films were investigated using attenuated total reflection Fourier transform infrared (FTIR) and Raman spectroscopy. Contact-angle measurements indicated that the contact angle increased from ∼76.5° for Surlyn alone to ∼89.6° for Surlyn coated with MTES.

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