Subject nanocomposites preparation

PEAs, some specific reviews can be taken into account [1-3], The present work is focused to the more recent developments performed with PEAs and highlights current activities on the biomedical field. The review is constituted by six sections the first and the second ones dealing with generic issnes snch as the synthetic methods applied and the derived polymer microstructures, while the third and fourth sections summarize more specific subjects such as preparation of hyperbranched and stiff polymers. The two last sections concern to PEAs prepared from renewable resources, paying special attention to polymers derived from a-amino acids, and specific applications like scaffolds with multiple functionalities, light-responsive materials, or nanocomposites. 

Preparation of polymer nanocomposites is nowadays an important research subject since polymer properties can be enhanced (e.g., modulus, strength, thermal resistance, per-meabifity, flammabifity resistance, and even biodegradability)... 

Nanocomposites of gold/polypyrrole have also been prepared by electrochemical methods. The composite system can be prepared by simultaneous reduction of AUCI4 and autopolymerization of pyrrole. The polymer coating can be removed by subjecting the composite to ultrasonic waves to obtain elemental gold nanoparticles of 2 nm in diameter. 

Mesoporous zirconia is a particulate oxide with properties for several applications such as catalyst or catalyst support [1, 2] and nanocomposite materials (Chap. 25) [3, 4]. Moreover, zirconia nanoparticles are subject of extensive studies dealing with the preparation of piezoelectric, electro-optic, dielectric materials with wide use, and hybrids for solid oxide fuel cells (SOFCs) [3, 5-8]. Zirconia is also a material in ceramic industry [9, 10]. 

Nanocomposites of PHBV (21 mol% of HV) and acidified MWCNT-COOH were prepared by solution blending followed by solvent casting at 70° C by Ma et al. (2012). Chloroform was used as solvent and the solution was subjected to ultrasonication. Nanocomposites were produced with 0, 0.5, 1, and 1.5 wt% of MWCNT-COOH and the acidification of MWCNT was made using a mixture of concentrated sulfuric and nitric acids. Adding MWCNT-COOH to PHBV implied in a growth of crystallinity in the nanocomposites, increase in crystallization... 

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