Search results for "Octene"

Epoxidation of dibenzocycloalkenes on Ti–Ge-MCM-41 and Ti-SBA-15 catalysts

2005

Abstract Epoxidation of a series of dibenzocycloalkenes: phenanthrene, 5H-dibenzo[ a , e ]cycloheptene, 5H-dibenzo[ a , c ] cycloheptene, 5,6-dihydrodibenzo[ a , e ]cyclo-octene, and dibenzo[ a , e ]cyclooctene with hydrogen peroxide was investigated on Ti- and Ge-modified Ti-incorporated-type mesoporous catalysts including MCM-41 and SBA-15 structures looking for the effect of the porous texture and Ge-promoting on both activity and selectivity to epoxide and H 2 O 2 efficiency. Ti–Ge-MCM-41 catalysts (Si/Ti = 43; Si/Ge = 85 and Si/Ti = 41; Si/Ge = 62) were prepared by a one-pot surfactant-assisted procedure based on the use of a cationic surfactant (CTAB, cetyltrimethylammonium bromide), …

Elastic properties of UV irradiated polyethylene-octene copolymer composites with functionalized multi-walled carbon nanotubes

2016

ABSTRACTPolyethylene-octene copolymer (E38) is melt compounded with carboxylated carbon nanotubes (CNT-COOH) in the presence of maleic anhydride grafted polyethylene (PEgMA). The effects of CNT-COOH in the amount of 1–10 wt. % on the mechanical properties of E38 based composite are investigated. It is revealed that addition of CNT-COOH considerably increases the stiffness and mechanical strength of the E38 based composites. The effect of UV irradiation on the structure as well as on the mechanical properties of E38/PEgMA/CNT-COOH composites is also investigated. Results of the investigation testify that UV resistance of the E38 based composites increases by increasing the content of CNT-COO…

Synthesis and catalytic performance in ethylene and 1-octene polymerization of chlorotitanium(IV) silsesquioxane complexes. Effect of increasing liga…

2016

Abstract The series of titanasilsesquioxanes that differ in a way of binding to the transition metal ( via one, two or three oxygen atoms) and type of nonreactive substituents bonded to inorganic oxygen-silicon cage ( i -Bu, Ph, c -C 6 H 11 ) were prepared by reacting of TiCl 4 with 1 eqv. of the silsesquioxane ligand. Upon treatment with an appropriate cocatalyst, all titanium precatalysts are active in ethylene and 1-octene polymerization and produce from low to high molecular weight polyethylenes and moderately ([ mmmm ] = 44–74%) isotactic poly(1-octene)s. The influence of polymerization parameters, type of cocatalyst and the silsesquioxane structure on the catalytic behavior of the tit…

Improvement of mechanical and dielectric properties of ethylene–octene copolymer by multi‐walled carbon nanotubes functionalized with poly(2,2′‐bithi…

2019

Aging of Nanosized ZnO Modified Polyoxymethylene Blends with Ethylene–octene Copolymer

2015

The influence of ethylene–octene copolymer and zinc oxide (ZnO) on structure and tensile stress–strain behavior of polyoxymethylene were investigated before and after ultraviolet weathering. Addition of ZnO considerably improved stress–strain characteristics of the ultraviolet-irradiation impaired composites. Crystallinities of ultraviolet-irradiated composites were affected by numerous competitive processes, including suppression of crystallization in the presence of multiple components in the system, nucleation induced by nanofiller, secondary crystallization and amorphization because of the chain scissions of the macromolecules. Addition of ZnO considerably improved stability of the comp…

Improved radiosynthesis and preliminary in vivo evaluation of the 11C-labeled tetrazine [11C]AE-1 for pretargeted PET imaging

2019

Pretargeted nuclear imaging based on the ligation between tetrazines and nano-sized targeting agents functionalized with trans-cyclooctene (TCO) has recently been shown to improve both imaging contrast and dosimetry in nuclear imaging of nanomedicines. Herein, we describe the improved radiosynthesis of a 11 C-labeled tetrazine ([ 11 C]AE-1) and its preliminary evaluation in both mice and pigs. Pretargeted imaging in mice was carried out using both a new TCO-functionalized polyglutamic acid and a previously reported TCO-functionalized bisphosphonate system as targeting agents. Unfortunately, pretargeted imaging was not successful using these targeting agents in pair with [ 11 C]AE-1. Howeve…

Microstructure of ethylene-1-hexene and ethylene-1-octene copolymers obtained over Ziegler–Natta catalysts supported on MgCl 2 (THF) 2

2001

Abstract The ethylene copolymerizations with 1-hexene or 1-octene in the presence of hydrogen using three catalysts, MgCl 2 (THF) 2 /VOCl 3 /Et 2 AlCl, MgCl 2 (THF) 2 /VCl 4 /Et 2 AlCl, MgCl 2 (THF) 2 /TiCl 4 /Et 2 AlCl, were investigated. It was found that the addition of hydrogen into the copolymerization feed reduces the molecular weight of the copolymers produced and decreases the activity of all the studied catalysts. The microstructure of the copolymers obtained was determined on the basis of 13 C NMR investigations and the reactivity ratios of the comonomers were calculated. The lack of tendency of the olefin comonomers to the creation of the polymer block was confirmed. It was found…

Orthometallation reactions of rhodium compounds containing orthohaloarylphosphines

1988

The reaction of RhCl3·.3H2O with a 3-molar proportion of P(o-ClC6H4)Ph2, (PCCl) at room temperature gives RhCl(PCCl)2 (1), in high yield. Reaction of [Rh(cot)2Cl]2, (cot = cyclooctene), with PCCl, sol12 molar ratio, also gives compound 1. Refluxing of a solution of 1 in 96% ethanol gives RhCl2(PC)(η2-PCCl), [PC  (C6H4)PPh2] (2). Complex 1 reacts with CO to give RhClCO(PCCl)2 (3). 31P NMR studies reveal that 1 exhibits a fluxional behaviour in solution in the temperature range −50 to 0 °C. The low temperature spectrum is consistent with the formulation RhCl(η2-PCCl)(η1-PCCl). In cyclic voltammetry complex 2 shows two two-electronic reduction processes, at −0.98 and −1.56 V. Electrochemical …

Tetrazine- and trans -cyclooctene-functionalised polypept(o)ides for fast bioorthogonal tetrazine ligation

2020

The inverse electron demand Diets-Alder (IEDDA) reaction-initiated ligation between 1,2,4,5-tetra-zines (Tz) and trans-cyclooctenes (TCO) is one of the fastest bioorthogonal reactions known today and is therefore increasingly used for in vivo click chemistry. Described herein is the synthesis of Tz- and TCO-functionalised polypeptides, polypeptoids and polypeptide-block-polypeptoids (polypept(o) ides) by ring-opening polymerisation of the corresponding N-carboxyanhydrides using Tz- or TCO-functional amine initiators. Despite the reactivity of tetrazines, polymers with low dispersity and high end group integrity can be obtained as observed by gel permeation chromatography (GPC), nuclear magn…

Ethylene homo- and copolymerization catalyzed by vanadium, zirconium, and titanium complexes having potentially tridentate Schiff base ligands

2021

Abstract New potentially tridentate Schiff base ligands, 2-[({4-[(3-N,N-dimethylamino)propyl] phenyl}imino)methyl]-4,6-di-tert-butylphenol (L1H) and 2-[{2-(N-phenyl-N-methylaminomethyl)-phenylimino}-methyl]-4,6-di-tert-butylophenol (L2H) were prepared and after deprotonation they were reacted with VOCl3 or MCl4 (where M = Zr or Ti) to produce corresponding complexes (L1-V, L2-V, L1-Zr, L2-Ti) with good yields. All new compounds were characterized by the 1H and 13C NMR as well as FTIR spectroscopic methods. Upon activation with Et2AlCl or EtAlCl2, both the vanadium complexes exhibited exceptionally high catalytic activities in the ethylene polymerization (up to 69,000 kg/(molV⋅h) for L1-V an…