Hard cover, 212 pagesPublisher InTech

The synthesis of organic-inorganic hybrids is an interesting approach as it offers the possibility of combining the advantages of organic polymer (elasticity, formability) and inorganic material (hardness, strength, high chemical resistance, and thermal stability). Gelatin-siloxane hybrid materials were prepared in the reaction of gelatin and organomodified silicones containing epoxy-and both epoxy-as well as fluoroalkyl groups. The hybrids obtained were characterized using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance ( 1 H NMR) spectroscopy, and scanning electron microscopic analysis. Thermal properties of the samples were evaluated by means of thermogravimetric analysis and differential scanning calorimetric measurements, showing the influence of type and amount of organosilicon compound on thermal properties of the hybrid materials. The samples obtained with siloxane containing fluoroalkyl groups as well as with mixed siloxanes revealed higher thermal stability than unmodified gelatin. Glass transition temperatures of the hybrids occurred at lower values than for gelatin, exhibiting the plasticizing effect of the applied siloxanes. Enthalpy values of the hybrids decreased, indicating the changes in the helical structure of gelatin caused by the introduction of siloxane. C

Environmental degradability of novel organic-inorganic cellulose acetate butyrate hybrids obtained via solgel process was investigated. The degradation of hybrids was studied under marine exposure conditions in the Baltic Sea for a period of 25 weeks. The influence of characteristic parameters of sea water on the degree of degradation monitored by changes of weight and optical microscopy was discussed. The degraded samples were also examined by FT-IR spectroscopy. It has been established that the CAB/silica hybrids are more susceptible to biodegradation in sea water environment than pure cellulose acetate butyrate.

Cellulose acetate butyrate nanocomposites synthesized via sol-gel method Summary -Novel hybrid nanocomposites were synthesized from modified cellulose acetate butyrate (MCAB) via sol-gel reaction at ambient temperature. The inorganic phase was introduced in situ by hydrolysis-condensation of tetraethoxysilane (TEOS) in different concentrations, using an acid catalyst, in the presence of organic polymer dissolved in acetone. Infrared spectroscopy (IR) was used to monitor modification of CAB and nanocomposites characterization. The silica network of obtained nanocomposites was characterized by solid state 29 Si NMR. Morphology of the samples and degree of dispersion of inorganic phase in the polymer matrix were investigated using atomic force microscopy (AFM). The organic-inorganic nanocomposites exhibit better mechanical properties than unmodified cellulose acetate butyrate.

In this study novel organic-inorganic hybrid nanocomposites were synthesized from modified cellulose acetate propionate (MCAP) via sol-gel reaction at ambient temperature. The inorganic phase was introduced in situ by hydrolysis-condensation of tetraethoxysilane (TEOS) in different concentrations, under acid catalysis, in the presence of organic polymer dissolved in acetone. The chemical modification of CAP was monitored by infrared spectroscopy (IR). The nanocomposites structure was characterized by IR analysis and solid state29Si NMR studies. The spectral data revealed that organic and inorganic phases are linked through covalent bound. Surface morphology of the samples and the degree of dispersion of inorganic phase in the polymer matrix were investigated using atomic force microscopy (AFM) and scanning electron microscopy (SEM). The actual incorporation of the inorganic component into the hybrid nanocomposites was deducted from the residual weight according to thermogravimetric analysis (TGA).

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Synthesis of organic-inorganic hybrids based on cellulose acetate butyrate RAPID COMMUNICATION Summary-Novel organic-inorganic hybrids based on cellulose acetate butyrate (CAB) were synthesized applying sol-gel process. The inorganic phase was introduced into polymer matrix by hydrolysis and condensation using tetraethoxysilane (TEOS) as the precursor, under acidic conditions. The obtained organic-inorganic hybrids were characterized by different techniques such as IR spectroscopy, thermogravimetric analysis (TGA), solid state 29 Si NMR and scanning electron microscopy (SEM). Organic-inorganic hybrids obtained with 20 % of diethyl phthalate (DEP) as plasticizer exhibit good transparency in comparison with unmodified CAB.

Novel gelatin-siloxane hybrid monoliths for heavy metal removal were prepared in the chemical reaction of gelatin with organomodified silicone containing epoxy group. Obtained porous hybrid materials were applied for adsorption of Cu(II), Cd(II) and Pb(II) from aqueous solutions. In this paper, the influence of siloxane amount used for the modification of gelatin on adsorbent stability and heavy metal removal was examined. The effect of pH values of the immersion liquid, as well as the contact time, was studied. Morphology, compressive strength and water absorption of hybrid monoliths were investigated. Desorption tests were also performed. The results showed that the higher the amount of the siloxane, the better stability of the hybrid monoliths in aqueous solutions. The highest values of adsorption capacity were observed for Pb(II) ions. The experimental maximum adsorption capacity determined for hybrid monoliths was 3.75 mg/g for Pb(II), 1.76 mg/g for Cu(II) and 1.5 mg/g for Cd(II). The desorption of metal ions for hybrid monoliths stable in aqueous solutions reached 70%.