Ethylene polymerization was carried out using Phillips chromium catalyst based on silica supports such as silica aerogel, SiO2 (Grace 643), and titanium modified SiO2 (G 643), and the results were compared with other catalysts based on SiO2 (Aldrich), SBA-15(Hex), SBA-15(Sp) and MCM-41. A combination of TGA, DSC, XRD, nitrogen adsorption, SEM, ICP, FTIR and other analyses were used to character...

In this paper, Polyimide/Montmorillonite Nanocomposites (PI/MMT NCs), based on aromatic diamine (4-Aminophenyl sulfone) (APS) and aromatic dianhydride (3,3',4,4'-benzophenonetetracarboxylic dianhydride) (BTDA) were prepared using in situ polymerization and solution-dispersion techniques. The prepared PI/MMT NCs films were characterized by X-ray diffraction (XRD), Fourier transform infrared spec...

We investigated the detailed structure of a surface-grafted phospholipid monolayer, which was polymerized in situ onto a methacryloyl-silanized solid surface. By the combined study of X-ray reflectivity and atomic force microscopy, the in situ polymerization step of the lipid molecules are sufficiently detailed to reveal the molecular structure of lipid molecules before and after in situ polyme...

bis(2-r-ind)zrcl2 (r: h or phenyl) was supported on different types of silica by in situ impregnation method and used for ethylene polymerization. in this method, the step of catalyst loading on support was eliminated and common alkyl aluminum (triisobutylaluminum, tiba) cocatalyst was used instead of expensive methyl aluminiumoxane (mao) cocatalyst in the polymerization. the effect of surface ...

The present research work describes an efficient method for facile synthesis of α-MnO2 nanorods by hydrothermal method and preparation of a series of polythiophene/manganese dioxide (PTh/MnO2) nanocomposites with various α-MnO2 ratios. These nanocomposites were fabricated by in-situ oxidative polymerization method using FeCl3 as oxidant, and characterized by Fourier transformed infrared (FT-IR)...

‎(St-co-BA) polymer through montmorillonite (MMT) nanocomposite emulsion is prepared by ‎in situ intercalative emulsion polymerization of styrene (St), butyl acrylate (BA) in the ‎presence of organic modified montmorillonite (OMMT) with different OMMT contents (0, ‎‎0.5, 1.0, 1.5, and 2.0 wt%). The synthetic compounds are characterized by FTIR, XRD. The ‎nanocomposite emulsions are characterize...

poly(styrene-co-butyl acrylate)/clay nanocomposites were synthesized via in situ atom transfer radical polymerization using activators generated by electron transfer in the presence of a montmorillonite ion-exchanged with mixed surfactants of dodecyl trimethyl ammonium bromide and vinyl trimethyl ammonium chloride. the living nature of polymerization is confrmed by occurrence of narrow molecula...

Polymerization reactions are commonly effected by exposing monomer formulations to some initiation stimulus such as elevated temperature, light, or a chemical reactant. Increasingly, these polymerization reactions are mediated by enzymes--catalytic proteins--owing to their reaction efficiency under mild conditions as well as their environmental friendliness. The utilization of enzymes, particul...

Two types of facile approaches toward ultrafine Ag/polymer hybrid nanoparticles (NPs) within 10 nm are introduced. Template and in-situ formation method are developed by photoreduction based on inverse microemulsion (IME) polymerization of N,N-dimethylacrylamide (DMAA). The template method refers to the usage of size-varied polymeric PDMAA NPs as templates for the preparation of Ag/PDMAA hybrid...