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Catalyst polymerizing

Ziegler catalysts Complex catalysts prepared by interaction between an organometallic derivative and a transition metal derivative. A typical catalyst is the product of the interaction of TiCU and AIBU3. These catalysts polymerize olefins, particularly ethylene, to polyolefins, the polymerization generally being in a siereoregular manner. [Pg.432]

Metallocene Catalysts. Polymerization of cycloolefins with Kaminsky catalysts (combinations of metallocenes and methylaluminoxane) produces polymers with a completely different stmcture. The reactions proceeds via the double-bond opening in cycloolefins and the formation of C—C bonds between adjacent rings (31,32). If the metallocene complexes contain bridged and substituted cyclopentadienyl rings, such as ethylene(hisindenyl)zirconium dichloride, the polymers are stereoregular and have the i j -diisotactic stmcture. [Pg.431]

Few aHyl monomers have been polymerized to useful, weH-characterized products of high molecular weight by ionic methods, eg, by Lewis acid or base catalysts. Polymerization of the 1-alkenes by Ziegler catalysts is an exception. However, addition of acidic substances, at room temperature or upon heating, often gives viscous liquid low mol wt polymers, frequently along with by-products of uncertain stmcture. [Pg.80]

Synthetic resins, such as phenoHc and cresyUc resins (see Phenolic resins), are the most commonly used friction material binders, and are usually modified with drying oils, elastomer, cardanol [37330-39-5] an epoxy, phosphoms- or boron-based compounds, or even combinations of two. They ate prepared by the addition of the appropriate phenol and formaldehyde [50-00-0] in the presence of an acidic or basic catalyst. Polymerization takes place at elevated temperatures. Other resin systems are based on elastomers (see Elastomers, synthetic), drying oils, or combinations of the above or other polymers. [Pg.274]

A monomer is a reactive molecule that has at least one functional group (e.g. -OH, -COOH, -NH2, -C=C-). Monomers may add to themselves as in the case of ethylene or may react with other monomers having different functionalities. A monomer initiated or catalyzed with a specific catalyst polymerizes and forms a macromolecule—a polymer. For example, ethylene polymerized in presence of a coordination catalyst produces a linear homopolymer (linear polyethylene) ... [Pg.302]

To prepare unbedded catalyst, polymerization was first carrirf out in a small a tetui glass reactor at room temperature for 1 hr in n-heptane at very low styreaie (xmcentration using Et[Ind]2ZrCl2/MAO catalyst with Al/Ti mole ratio of20-200. After the rraiction, a small part of the solid fraction (embedded catalyst) was isolated fi om the liquid phase for the... [Pg.849]

Calculated from Michaelis-Menten constants using lipase catalyst. Polymerization with zinc octanoate/butyl alcohol initiator system in bulk. [Pg.211]

The CO-reduced catalyst polymerizes ethylene much like its ethylene-reduced hexavalent parent and produces almost identical polymer [4]. Since the polymer properties are extremely sensitive to the catalyst pretreatment. [Pg.11]

Monomer Catalyst Polymerization Time (hr) Yield (%) inhc (dL/q) Tg (°l... [Pg.64]

Structurally related complexes are also active initiators for the living polymerization of carbo-diimides (which are isoelectronic to isocyanates).1003 The proposed intermediate for this polymerization process is a metal amidinate (Scheme 29), and the model complex (349) has been reported to be a highly efficient catalyst, polymerizing 500 equivalents of di- -hexylcarbodiimide in less than 10 s. A more hydrolytically robust series of initiators has also been developed, based upon copper(I) and copper(II) amidinates.1004... [Pg.59]

Polymeric carbon refers to chains of carbon monomers (surface carbide) that are connected by covalent bonds. It has been shown recently47 that the barrier for C-C coupling on flat surfaces (1.22 eV) is half that for a step site (2.43 eV), and may indicate that the growth of these polymeric species is favored on terraces. Polymeric carbon may also refer to carbon chains that contain hydrogen. In the case of CO hydrogenation on ruthenium catalysts, polymeric carbon has been identified as a less reactive carbon that forms from polymerization of CHX and has an alkyl group structure.48... [Pg.56]

PDO/DMT molar ratio Catalyst Reaction temperature/time /pressure Catalyst Polymerization temperature/time /pressure Comments Reference... [Pg.365]

Chemical/Physical. In the dark, styrene reacted with ozone forming benzaldehyde, formaldehyde, benzoic acid, and trace amounts of formic acid (Grosjean, 1985). Polymerizes readily in the presence of heat, light, or a peroxide catalyst. Polymerization is exothermic and may become explosive (NIOSH, 1997). [Pg.1007]

Uses. In specialty reactions as a source of Cr manufacture of catalysts polymerization of olefins curing agent for urethane resins... [Pg.104]

FIGURE 5.1 Proposed mechanism for soluble stereoregulating catalyst polymerizations. [Pg.152]

The general issues from literature surveys dealing with lanthanide initiators reveal the following (1) catalyst precursors with larger lanthanide metals polymerize lactide faster than metals of smaller radii, (2) lanthanide catalysts polymerize lactide at slower rates than cyclic esters such as s-caprolactone and, in most cases. [Pg.253]

Copolymerization reactions Copolymerization experiments with styrene and MMA employed molar fractions of 20, 40, 60, and 80% comonomers, which were reacted in ethanol 1,2-dichIorethane 60 40 (by volume) mixtures and benzoyl peroxide as catalyst. Polymerizations were carried out at 70°C. The reactions were quenched by the addition of methanol as non-solvent, and the copolymer was isolated by centrifugation. Copolymer analysis employed UV spectroscopy for copolymers with MMA, and methoxyl content determination according to a procedure by Hodges et al. (16) in the case of styrene copolymers. Reactivity ratios were determined in accordance with the method by Kelen-Tiidos (17) and that by Yezrielev-Brokhina-Roskin (YBR) (18). Experimental details and results are presented elsewhere (15). [Pg.516]

Experiment Catalyst Polymerization Modifier Polymerization Modifier (mmol) Reaction Temperature (°C) Yield (%) Efficiency (gPP/mgHf)... [Pg.44]

Borazines, particularly polymeric compounds, have been extensively investigated as preceramic materials from which coatings and fibers of boron nitride can be produced upon thermolysis. B-aryl and halogeno-amino borazines are reported to have use as fire retardants in cotton and nylon textiles. Other reported uses for borazines are as epoxy resin catalysts, polymerization inhibitors of unsaturated alcohols and esters, and catalysts for polymerization of alkenes (95). [Pg.268]

It is known that the polymerization of ethylene by trialkyl aluminum is not a rapid reaction at normal pressures and temperatures. Ziegler, Gellert, Holzkamp, Wilke, Duck and Kroll (72) have found that ethylene was polymerized to higher trialkylaluminums only at elevated temperatures and pressures. Anionic hydride transfer commonly occured under these conditions. However, the addition of a transition metal halide such as titanium tetrachloride, the classical Ziegler catalyst, polymerized ethylene rapidly under mild conditions. [Pg.373]

Krauss and Stach (31) demonstrated that the hexavalent catalyst can be quantitatively reduced by CO at 350°C to divalent chromium. This material has no y-phase resonance but is active for ethylene polymerization, indicating that Cr(II) is definitely an active valence.1 These results have since been confirmed by several other laboratories, including this one (30). In fact, Hogan concluded, as early as 1959 from similar reduction studies, that the active species must be divalent. The CO-reduced catalyst polymerizes ethylene in a high-pressure autoclave much like its hexavalent parent, and produces almost identical polymer. Since the polymer properties are extremely sensitive to the catalyst pretreatment, this is a strong endorsement for the conclusion that Cr(II) is probably also the active species on the commercial catalyst after reduction by ethylene. [Pg.54]

Metallocene Catalysts. Higher a-olefins can be polymerized with catalyst systems containing metallocene complexes. The first catalysts of this type (Kaminsky catalysts) include metallocene complexes of zirconium such as biscyclopentadienylzirconium dichloride, activated by methylaluminoxane. These catalysts polymerize a-olefins with the formation of amorphous atactic polymers. Polymers with high molecular weights are produced at decreased temperatures and have rubber-like properties. [Pg.1149]


See other pages where Catalyst polymerizing is mentioned: [Pg.383]    [Pg.425]    [Pg.430]    [Pg.352]    [Pg.148]    [Pg.172]    [Pg.134]    [Pg.87]    [Pg.299]    [Pg.4]    [Pg.196]    [Pg.98]    [Pg.843]    [Pg.573]    [Pg.102]    [Pg.4]    [Pg.295]    [Pg.406]    [Pg.83]    [Pg.268]    [Pg.70]    [Pg.352]    [Pg.115]    [Pg.1148]    [Pg.1149]    [Pg.1149]   
See also in sourсe #XX -- [ Pg.445 ]




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ATRP catalysts radical polymerization

Acid polymerization catalysts

Alcohol catalysts polymerization

Alkali metal catalysts, polymerization using

Alkene polymerization Ziegler-Natta catalysis and metallocene catalysts

Alkene polymerization catalysts

Alkene polymerization, metal complex catalysts

Alumina heterogeneous polymerization catalysts

Anionic ring-opening polymerizations, catalysts, potassium

As polymerization catalysts

Basic catalysts polymerization

Basic catalysts polymerization mechanism

Boron catalysts ring-opening polymerization

Carbenes polymerization catalysts (type

Carbenes polymerization catalysts derived from

Catalysis/catalysts olefin polymerization

Catalyst Polymerization Kinetics and Polyethylene Particle Morphology

Catalyst chain transfer polymerization

Catalyst chain transfer polymerization technique

Catalyst design 436 - polymerization

Catalyst for epoxide polymerization

Catalyst for ethylene polymerization

Catalyst for oxidative polymerization

Catalyst precursors for polymerization

Catalyst templated polymeric

Catalyst-transfer polymerization

Catalysts Norbornene polymerization

Catalysts ethylene oxide polymerization

Catalysts for anionic polymerization

Catalysts for olefin polymerization

Catalysts for polymerization

Catalysts polymeric catalysis

Catalysts polymeric, chiral

Catalysts polymeric, kinetics

Catalysts polymeric, properties

Catalysts radical polymerization

Catalysts stereospecific chain polymerization

Catalysts stereospecific polymerization

Catalytic olefin polymerization catalyst system

Chemical polymerization catalyst

Chemical polymerization catalyst copolymers

Chiral linear polymeric catalysts

Chromium Polymerization Catalysts

Chromium/silica catalyst polymerization over

Clay as a Polymerization Catalyst Support

Condensation polymerization catalysts

Controlled polymerization transition metal containing catalysts

Coordination catalysts stereospecific chain polymerization

Coordination polymerization Phillips catalysts

Coordination polymerization Ziegler-Natta catalysts

Coordination polymerization catalysts

Coordination polymerization late transition metal catalysts

Coordination polymerization single-site catalysts

Cross polymeric catalysts

Cso as Co-catalyst for Polymerization

Discovery of Highly Active Molecular Catalysts for Ethylene Polymerization

Early Metal Olefin Polymerization Catalysts

Effects of Polymerization Catalyst Residues

Epoxide polymerization catalysts

Ethanol, ring-opening polymerization catalysts

Ethylene Polymerization Activity of Zr- and Ti-FI Catalysts

Ethylene Polymerization Behavior of FI Catalysts with Cocatalysts Other than MAO

Ethylene chromium polymerization catalysts

Ethylene polymerization catalysts

Ethylene polymerization iron catalysts

Ethylene polymerization molybdenum catalysts

Ethylene polymerization with Ziegler catalysts

Ethylene polymerization, with Lewis acid grafted heterometallic catalysts

Ethylene polymerizations, highly active molecular catalysts

Graft polymerization phase transfer catalysts

Graft polymerization radical catalysts

Helical polymeric catalysts

Helical polymeric catalysts reactions

Heterogeneous Polymerization Catalysts Derived from Transition Metal Alkyl Compounds

Heterogeneous catalysts, site-controlled stereospecific polymerizations

Heterogeneous polymeric catalysts

Heterogeneous polymerization solid catalysts

Heterogenized transition metal catalysts polymerization with

Highly Active Ethene Polymerization Catalysts with Unusual Imine Ligands

Homogeneous asymmetric catalysis polymeric catalysts

Homogeneous catalyst Ziegler-Natta polymerization

I 5 Well-Defined Transition Metal Catalysts for Metathesis Polymerization

Imidazole groups, polymeric catalysts

Immobilized polymerization catalysts

In-situ Polymerization of Olefins with Coordination Catalysts Supported on Clays

Iron catalysts olefin polymerization

Iron catalysts ring-opening polymerization

Isocyanates, polymerization catalysts

Isomerization Polymerizations with Coordination Catalysts

Kaminsky-type polymerizations catalysts

Late-Metal Olefin Polymerization Catalysts

Latent Ruthenium Catalysts for Ring Opening Metathesis Polymerization (ROMP)

Lewis catalyst, polymeric

Linear Polymeric Catalysts

Liquid slurry polymerization with catalyst

Living polymerization catalysts

Mechanism of Polymerization with Supported Chromium Catalysts

Metal catalysts polymerization

Metal catalysts polymerization process

Metal catalysts, polymerizations using

Metal oxides polymerization catalysts

Metal-containing catalysts, polymerization

Metallocene catalysts for olefin polymerization

Metallocene catalysts olefin polymerization

Metallocene catalysts polymerization mechanism

Metallocenes polymerization catalysts

Metal—ligand bonds polymerization catalysts

Metathesis polymerization catalysts

Molecular catalysts designing, with styrene polymerization

Neutral Group 3 Metallocene Complexes as Catalysts of Polymerization

Newer Metallocene Catalysts for Olefin Polymerization

Next Generation Chromium-Based Ethylene Polymerization Catalysts for Commercial Operations

Nickel catalyst, diene polymerization

Of polymeric catalysts

Olefin Polymerization with Coordination Catalysts

Olefin polymerization catalyst precursors

Olefin polymerization catalysts

Olefin polymerization co-catalysts

Olefins heterogeneous polymerization catalysts

Organochromium catalysts polymerization activity

Organolithium polymerization catalysts

Organometallic Fluorides of Group-4 Metals as Efficient Catalysts for Polymerization

Other Catalysts for the Polymerization of Acetylene

Oxirane polymerization catalyst

P. Beletskaya and Andrei V. Cheprakov 2 Palladium Catalysts Immobilized on Polymeric Supports

POLYMERIC REAGENTS AND CATALYSTS

Palladium catalysts, polymeric

Patented Uses as Components of Polymerization Catalysts

Phase transfer catalyst polymerization

Phase transfer catalysts, chiral polymeric

Phillips chromium catalysts ethylene polymerization

Phillips chromium/silica polymerization catalyst

Platinum catalysts ring-opening polymerization

Poly(l-Pentenylene) by Metathesis Polymerization of Cyclopentene with a Ziegler-Natta-Catalyst in Solution

Polymeric Lewis acid-catalyst

Polymeric borane catalyst

Polymeric catalyst-substrate complex

Polymeric catalysts

Polymeric catalysts for

Polymeric catalysts, quinine

Polymeric super acid catalysts

Polymerization 1,5-hexadiene with metallocene catalysts

Polymerization Catalyst Composition

Polymerization Kinetics with Multiple-site Catalysts

Polymerization Mechanism with Coordination Catalysts

Polymerization Phillips catalyst

Polymerization Using Ziegler-Natta Catalysts

Polymerization Vandenberg catalyst

Polymerization Zeigler-Natta catalysts

Polymerization by catalysts

Polymerization by transition metal catalysts

Polymerization catalysts

Polymerization catalysts Ziegler-Natta

Polymerization catalysts alkyllithium

Polymerization catalysts free radical

Polymerization catalysts neodymium

Polymerization catalysts, solid state

Polymerization catalysts, soluble

Polymerization complex catalysts

Polymerization heterogeneous catalysts

Polymerization kinetics for single-and multiple-site catalysts

Polymerization metallocene catalysts

Polymerization nickel catalysts

Polymerization of Ethylene on a Supported Catalyst in Organic Suspension

Polymerization purely organic catalysts

Polymerization with Metallocene Catalysts

Polymerization with Ziegler-Natta Catalysts

Polymerization, by metallocene catalysts

Polymerization, elastomer synthesis catalysts

Polymerizations with Coordination Catalysts

Polyolefins propylene polymerization, catalyst

Polypropylene metallocene polymerization catalysts

Propylene polymerization Ziegler-Natta catalysts

Propylene polymerization with modified Ziegler-Natta catalysts

Propylene polymerization, catalyst

Propylene polymerization, catalyst analysis

Propylene polymerization, catalyst copolymerization

Propylene polymerization, catalyst systems

Radical Polymerizations with 1 Organic Catalysts

Rare-Earth Metal Complexes as Catalysts for Syndiospecific Styrene Polymerization

Recent Catalysts for Living Polymerization

Recyclable polymerization catalyst

Refinery catalysts polymerization

Ring opening metathesis polymerization catalyst incorporation

Ring-Opening Metathesis Polymerization of Norbornene Using an MTO Catalyst

Ring-opening polymerization aluminium catalysts

Ring-opening polymerization catalysts

Ring-opening polymerization cationic catalysts

Ring-opening polymerization metal catalysts

Ring-opening polymerization organic catalysts

Ruthenium catalysts ring-opening polymerization

Scandium catalysts, olefin polymerization

Second-Generation Propylene Polymerization Catalysts

Silica heterogeneous polymerization catalysts from

Silica-alumina catalysts, active sites ethylene polymerization

Silica-alumina polymerization catalyst

Silicon catalysts ring-opening polymerization

Single site catalysts polymerization

Single-Site Ethylene Polymerization Catalysts

Site-controlled stereospecific polymerizations catalyst chirality

Soluble Olefin Polymerization Catalysts

Soluble Polymeric Supports and Catalyst Separation Methods

Some General Features of Propagation Centers in One-Component Polymerization Catalysts

Some mechanisms of olefin polymerization by Ziegler catalysts

Stereochemistry of Polymerization Ziegler-Natta Catalysts

Stereospecific Polymerization of Propylene with Ziegler-Natta-Catalysts in Organic Suspension

Stereospecific Polymerization of Styrene with Ziegler-Natta-Catalysts

Stereospecific catalysts, structure polymerization

Stereospecific living polymerization, acetylenes catalysts

Stereospecific polymerizations catalyst chirality

Stereospecific polymerizations heterogeneous catalysts

Styrene polymerization catalysts

Supported metal oxide catalysts polymerization mechanism

Supported transition metal complex catalysts polymerization

Syndiospecific catalysts/polymerization

The First Carbene-tethered Polymeric Catalyst

Thorium polymerization catalysts

Titanium tetrachloride polymerization catalyst

Transesterification, ring-opening polymerization catalysts

Transition Metal Catalysts for Ethylene Polymerization

Transition metal alkyl compounds heterogeneous polymerization catalysts

Transition metal catalysts polymerization

Transition metal catalysts, butadiene polymerization

Transition metal catalysts, initiation ring-opening polymerization

Transition metal heterogeneous polymerization catalysts

Transition polymerization catalyst

Trialkylaluminum polymerization catalysts

Uranium catalysts polymerization

Ylide Nickel Complexes Novel Polymerization Catalysts

Ziegler polymerization catalyst

Ziegler-Natta catalyst, vinyl chloride polymerization

Ziegler-Natta catalysts acetylene polymerization

Ziegler-Natta catalysts alkene polymerization

Ziegler-Natta catalysts polybutadiene polymerization

Ziegler-Natta catalysts polyisoprene polymerization

Ziegler-Natta catalysts polymerization reactions

Ziegler-Natta olefin polymerization catalyst

Ziegler-Natta olefin polymerization soluble catalyst systems

Ziegler-Natta polymerization Metallocene catalysts

Ziegler-Natta polymerization catalyst site control

Ziegler-Natta polymerization metal oxide catalysts

Ziegler-Natta polymerization single-site catalysts

Ziegler-Natta-type olefin polymerization catalysts

Ziegler/Natta catalysts, diene polymerization

Zirconium catalyst in alkene polymerization

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