Interaction polymer-nanoparticle

The colloidal dispersions and thin films containing poly-iV-(epoxypropyl)-carbazole (PEPC) and Ag-Au nanoparticles were prepared and investigated by TEM and UV-vis spectroscopy. The interaction between poly-iV-(epoxypropyl)-carbazole and Ag-Au nanoparticles were studied by IR-spectroscopy. It was shown that interaction of nanoparticles and polymer functional groups is determined by the conditions of a polymer addition. 

In highly interactive polymer-particle systems, solidlike yield behavior can be observed even at temperatures above the glass transition temperature of the polymer [54]. Polymer molecules can adopt stretched configurations that allow them to adsorb to the surfaces of many particles. Relative motion between polymer chains is retarded by immobilization due to polymer confinement between nanoparticle surfaces. The equilibrium thickness of the immobilized polymer layer is of the order of the radius of gyration of the molecule. Eiller particles can be regarded as hard cores surrounded by immobilized polymer shells of comparable size. 

Most important factors that influence the overall conductivity of polymer-based nanocomposites are the character of the polymer matrix, the properties of nanoparticles, concentration of nanoparticles, and interfacial interactions of nanoparticles and polymer matrix. 

Musyanovych A, Schmitz-Wienke J, Mailaender V, et al. (2008) Preparation of biodegradable polymer nanoparticles by miniemulsion technique and their cell interactions. Macromol Biosci 8 127-139... 

Rittigstein, R, and Torkelson, J. M., Polymer-nanoparticle interfacial interactions in polymer nanocomposites confinement effects on glass transition temperature and suppression of physical ageing, J. Polym. Sci. Polym. Phys., 44, 2935-2943 (2006). 

The introduction of nanoceramics in thermoplastics or thermosets seems to be a promising route to improving mechanical moduli, particularly of elastic matrices. The macroscopic properties are governed by the nature of polymer-nanoparticle interactions. In this chapter, specific attention will be paid to nanocomposites of polyamide (PA) with HAp. Considering their attractive viscoelastic properties, semiaromatic polyamides (e.g., PA-llTlO) have been chosen as the matrix [Choe et al., 1999]. Recently, several publications have been devoted to one-dimensional nanostructures with high-aspect-ratio particles. Promising data have been obtained for the polymer/nanowire-nanotube nanocomposites. 

Apart from polyplexes that are a spontaneous outcome of polynucleotide condensation by cationic polymers, nanoparticles can be obtained by directly using cationic polymers such as chitosan, or by coating nanoparticles that are not cationic by grafting/copolymerization, or by simple electrostatic interactions with cationic polymers, lipids or surfactants. 

Smith, J. S., Bedrov, D., and Smith, G. D. A molecular dynamics simulation study of nanoparticle interactions in a model polymer-nanoparticle composite. Compos Sci Tech-noL, 63,1599-605 (2003). 

The presence of coupling agent has also enhanced the dispersion of the nanoparticle in the polymer matrix. Incorporation of 5 wt% of trimellitic anhydride chloride-treated CaCO in PET and the coupling agent enhanced the dispersion of the nanoparticle in the polyethylene terephthalate matrix [63]. The coupling agent acts as bi-fimctional reactant. Anhydride ends xmdergo acid-base interactions with nanoparticle surface calcium ions, which may lead to better dispersion. 

A comparable solid-like response, presumably owing to a similar filler network and same qualitative rheological trend, was observed in EVA/MMT-filled nanocomposites, but only when the EVA copolymer contained a high polar comonomer fraction (>28%). In addition, the polymer/nanoparticle interactions of PE nanocomposites prepared by diluting a EVA/MMT masterbatch in PE were substantially weaker than the ones of the respective... 

Composites with starch or cellulose, drugs, and highly disperse adsorbents can be used for medicinal purposes. These nanocomposites are characterized by enhanced activity of adsorbed biopolymers or polymers and/or drugs because of their transformation into a nanostate during interactions with solid nanoparticles because each adsorbate molecule interacts with nanoparticles. TSDC, DRS, DSC, FTIR, and other methods allow to study structural features of similar nanocomposites. NMR spectroscopy with layer-by-layer freezing-out of bulk and bound water as... 

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