Synthesis and characterization of monodisperse spherical zirconia particles

in Journal of Sol-Gel Science and Technology (1997), 8

Synthesis and characterization of new inorganic polymeric composites based on kaolin or white clay and on ground-granulated blast furnace slag

in Journal of Materials Research (2003), 18(11), 2571-2579

Alkali activation of dehydroxylated kaolin or clay yielded high-strength polymeric materials, so-called geopolymers. They were synthesized by mixing the aluminosilicate with solutions of sodium ... [more ▼]

Alkali activation of dehydroxylated kaolin or clay yielded high-strength polymeric materials, so-called geopolymers. They were synthesized by mixing the aluminosilicate with solutions of sodium metasilicate and KOH followed by adding 45 wt.% of ground-granulated blast furnace slag. The influence of the aluminosilicate source, its activation temperature, and the order of mixing raw materials were studied on the workability of the blending paste, the microstructure, and the Vickers hardness of the geopolymer samples. The polymeric material is completely amorphous according to x-ray diffraction. Solid-state 27Al and 29Si magic-angle-spinning nuclear magnetic resonance showed that the geopolymer consists of AlO 4 and SiO 4 tetrahedra linked together through a polymeric network constituted by branched entities SiQ 4(4Al) and SiQ 4(3Al), but also by less-polymerized silicates SiQ 1 and SiQ 2. Scanning electron microscopy showed a homogeneous polymeric gel matrix containing unreacted slag (and quartz) grains; thermogravimetric analysis and differential scanning calorimetry exhibited a high content of water and an elevated melting point (1260 °C). Vickers hardness values are in the range of 200 MPa. [less ▲]

Synthesis and characterization of novel vinyl copolymers containing N-vinylphthalimide: Comonomers reactivity ratios and thermal stability

in European Polymer Journal (2007), 43(9), 3849-3855

N-Vinylphthalimide (NVPh) was copolymerized with p-methylstyrene (PMS), p-methoxystyrene (PMOS) and p-chlorostyrene (PCIS) at 60 degrees C, with 2,2'-azo-bis-isobutyronitrile as an initiator. Copolymer ... [more ▼]

N-Vinylphthalimide (NVPh) was copolymerized with p-methylstyrene (PMS), p-methoxystyrene (PMOS) and p-chlorostyrene (PCIS) at 60 degrees C, with 2,2'-azo-bis-isobutyronitrile as an initiator. Copolymer composition was determined by elemental analysis in case of the N-vinylphthalimide and p-methylstyrene comonomer pair, whereas proton nuclear magnetic resonance was used for the analysis of the two other copolymers. The reactivity ratios for each comonomer pair were estimated by the classical Fineman-Ross and Kelen-Tudos linear techniques. These data showed that N-vinylphthalimide was less reactive in all the cases and that the comonomer distribution, that was basically random in the poly(N-vinylphthalimide-co-p-methylstyrene) and poly(N-vinylphthalimide-co-p-chlorostyrene) copolymers, was rather alternate in the third poly(N-vinylphthalimide-co-p-methoxystyrene) copolymer. The difference observed in the reactivity ratios was discussed in reference to the structure of the comonomer units and the parent radicals. The thermal properties of the copolymers and model homopolymers were investigated by differential scanning calorimetry and thermogravimetric analysis. [less ▲]

Synthesis and characterization of porous carbon xerogels and ordered mesoporous carbons for anode materials in Li-based batteries

in Fagadar-Cosma, Eugenia (Ed.) Insights into novel solid materials, their recyclability and integration into Li polymer batteries for EVs. Future research directions in this field.:Book of abstracts (2012, July 04)

Synthesis and characterization of porous silica-alumina xerogels

in Journal of Sol-Gel Science and Technology (1997), 8

Synthesis and characterization of recyclable chemically cross-linked shape memory materials

Conference (2012, September 10)

Synthesis and characterization of reversibly core cross-linked micelles sensitive to reductive environment

Poster (2011, May 12)

Synthesis and characterization of reversibly cross-linked shape memory materials

Poster (2010, September 07)

Synthesis and compatibilization ability of hydrogenated polybutadiene-b-polyamide 6 diblock copolymer in low density polyethylene and polyamide 6 blends

in Polymer (2002), 43(19), 5347-5354

This paper describes the synthesis of hydrogenated polybutadiene-b-polyamide 6 (HPB-b-PA6), a pure diblock copolymer, which consists of three main steps: synthesis of hydroxyl terminated polybutadiene ... [more ▼]

This paper describes the synthesis of hydrogenated polybutadiene-b-polyamide 6 (HPB-b-PA6), a pure diblock copolymer, which consists of three main steps: synthesis of hydroxyl terminated polybutadiene, its hydrogenation and functionalization with an epsilon-caprolactam blocked diisocyanate. In a third step the functionalized HPB is copolymerized with epsilon-caprolactam monomer via ring opening anionic polymerization. The compatibilization ability of the synthesized pure diblock copolymer was evaluated in low-density polyethylene (LDPE)/polyamide 6 (PA6) blends. The investigation includes phase morphology development using both optical and electron scanning microscopy. The ultimate tensile properties of the modified and non-modified blends were also evaluated. The synthesized pure diblock copolymer exhibits very interesting interfacial activity both in terms of particle size reduction and improvement of the interfacial adhesion between the incompatible LDPE/PA6 phases. The tensile properties of the investigated blends were also significantly affected by the addition of the copolymer. The efficiency of compatibilization was found to be very sensitive to the molecular characteristics such as composition and molecular weight of the copolymer. Among the copolymers investigated a copolymer containing 24 wt% PA6 and having a total molecular weight (M) over bar (a) of 87,000 was found to exhibit the most efficient interfacial activity. [less ▲]

Synthesis and deposition of water-dispersed prussian blue nanocrystals on polymers and CNTs

in Progress in Colloid & Polymer Science (2006), 132

Nanoparticles can be used for decoration and functionalization of single polymer molecules that have been adsorbed to a solid substrate. Initial attempts to prepare Prussian Blue nanoclusters by a layer ... [more ▼]

Nanoparticles can be used for decoration and functionalization of single polymer molecules that have been adsorbed to a solid substrate. Initial attempts to prepare Prussian Blue nanoclusters by a layer-by-layer deposition technique of hexacyanoferrate anions and ferric cations onto isolated polycation chains in water failed because of the desorption of the first layer upon deposition of the next one. A simple method for the preparation of charge-stabilized Prussian Blue nanoparticles of readily adjustable size is reported. Prussian Blue nanoparticles have been purified by addition of non-solvents and redispersed in water without aggregation. Thus formed Prussian Blue nanoparticles are crystalline and display a long-range ferromagnetic ordering at 5.1 K. Prussian Blue nanoparticles were selectively deposited along single polycation molecules to form a one-dimensional array or were attached to the surface of carbon nanotubes (CNTs) functionalized with poly2-vinylpyridine (P2VP). These nanoparticle-based nanostructures might be useful materials for manufacture of electrooptical devices, or mechanically robust ion-sieving membranes. [less ▲]