Synthesis, characterization and ethylene polymerization by metallasilsesquioxane

Abstract

a Soluble complexes of group (IV) metallocenes anchored on a substituted polyhedral oligomeric silsesquioxane trisilanol support were prepared and characterized. These catalyst precursors formulated as [M(O^O^O)X] are found to be active in polymerization of ethylene at high temperature in combination with ethylaluminum sesquichloride (Et 3 Al 2 Cl 3, EASC) as co-catalyst. The polyethylene obtained by these catalysts is linear, crystalline and displays narrow dispersity. The unique low molecular weight PE formed in this reaction exhibits properties comparable to commercial micronized PE waxes that have potential industrial applications in surface coating and ink formulations.

POSS nanostructures in catalysis

“…Under the same reaction conditions, unless for a lower ethylene pressure (20.7 bar), the anchored group (IV) metal complexes 119-125 were evaluated in polymerization of ethylene in combination with EASC. 141,142 According to data, for complexes 119-122 the achieved productivities were in the range values 2.5-42.1 KgPE gcatalyst -1 h -1 with the overall order of activity 119>120>121>122. By changing metal active sites, titanium based complex 122a exhibited better productivity than zirconium-or hafnium-POSS complexes (122a>122b>122c).…”

Silsesquioxanes and their application in the synthesis of polymeric materials

“…Silseskwioksany z powodzeniem stosuje siê jako sk³adniki uk³adów katalitycznych w reakcjach metatezy [90], epoksydacji [91][92][93][94], hydroformylowania [95], Dielsa-Aldera [96] oraz polimeryzacji [97]. W ostatnich latach podjêto tak¿e próby otrzymywania silseskwioksanów z wbudowanymi atomami metali przejoeciowych, np.…”

Silsesquioxane organofunctionalized with 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole: Preparation and subsequent reaction with silver and potassium hexacyanoferrate(III) for detection of l-cysteine

“…POSSs are known as hybrid organic-inorganic nanocomposites -the inorganic core provides stability to the molecule and organic arms can establish its specific properties [7][8][9][10][11]. In particular, due to the highly symmetrical three-dimensional nature of their nucleus, POSSs are good precursors for the production of hybrid organic-inorganic materials [6,12] and these nanomaterials have recently shown great or advantageous functional properties for a wide range of technological applications, such as dendritic precursors [13][14][15][16], polymer precursors [17,18], as precursors for developing liquid crystals [19,20], homogeneous and heterogeneous catalysis [21,22], electroactive films [23], additives [24,25], antibacterial [26], and also used in thin films and coatings for various applications, including nanocomposites [10,11,27]. Thus, silsesquioxanes containing the chlorine element at their ends, such as octakis(3-chloropropyl)octasilsesquioxane, can be easily modified by the organic/inorganic process.…”