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Polymer stabilization stabilizers

The interaction between metals and metallic compounds and polymers is extremely complex, leading either to polymer degradation (accelerators or photosensitizers) or to polymer stabilization (stabilizers, retarders, metal deactivators). [Pg.544]

Formaldehyde homopolymer is composed exclusively of repeating oxymethylene units and is described by the term poly oxymethylene (POM) [9002-81-7]. Commercially significant copolymers, for example [95327-43-8] have a minor fraction (typically less than 5 mol %) of alkyUdene or other units, derived from cycHc ethers or cycHc formals, distributed along the polymer chain. The occasional break in the oxymethylene sequences has significant ramifications for polymer stabilization. [Pg.56]

Additioaal uses for higher olefias iaclude the productioa of epoxides for subsequeat coaversioa iato surface-active ageats, alkylatioa of benzene to produce drag-flow reducers, alkylation of phenol to produce antioxidants, oligomeriza tion to produce synthetic waxes (qv), and the production of linear mercaptans for use in agricultural chemicals and polymer stabilizers. Aluminum alkyls can be produced from a-olefias either by direct hydroalumination or by transalkylation. In addition, a number of heavy olefin streams and olefin or paraffin streams have been sulfated or sulfonated and used in the leather (qv) iadustry. [Pg.442]

Although examples in the Kureha patent Hterature indicate latitude in selecting hold times for the low and high temperature polymerization periods, the highest molecular weight polymers seem to be obtained for long polymerization times. The addition of water to PPS polymerizations has been reported to effect polymer stabilization (49), to improve molecular weight (50,51), to cause or enhance the formation of a second Hquid phase in the reaction mixture (52), and to help reprecipitate PPS from NMP solution (51). It has also been reported that water can be added under pressure in the form of steam (53). [Pg.444]

Many antioxidants ia these classes are volatile to some extent at elevated temperatures and almost all antioxidants are readily extracted from their vulcanizates by the proper solvent. These disadvantages have become more pronounced as performance requirements for mbber products have been iacreased. Higher operating temperatures and the need for improved oxidation resistance under conditions of repeated extraction have accelerated the search for new techniques for polymer stabilization. Carpet backiag, seals, gaskets, and hose are some examples where high temperatures and/or solvent extraction can combine to deplete a mbber product of its antioxidant and thus lead to its oxidative deterioration faster (38,40). [Pg.247]

MURRAY, R. w.. Chapter entitled Prevention of Degradation by Ozone in Polymer Stabilization (Ed. HAWKINS, w. L.), Wiley, New York (1972)... [Pg.157]

The early recognition of the role of stable nitroxyl free radicals, e.g., 2,2,6,6-tetramethyl-4-oxopiperidine, and their hindered amine precursors, in polymer stabilization soon led to the development of the hindered amine light stabilizer (HALS) class of photoantioxidants. The first HALS, Tinuvin 770, AO-33, (commercialized in 1974) proved to offer much higher UV-stabil-ity to polymers than any conventional UV-stabilizer available at the time such as UV-absorbers, nickel compounds and benzoates. Table 3). [Pg.115]

Prior to the development of NMP, nitroxides were well known as inhibitors of polymerization (Section 5.3.1). They and various derivatives were (and still are) widely used in polymer stabilization. Both applications are based on the property of nitroxides to efficiently scavenge carbon-centered radicals by combining with them at near diffusion-controlled rates to form alkoxyamines. This property also saw nitroxides exploited as trapping agents to define initiation mechanisms (Section 3.5.2.4). [Pg.471]

Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) are also very useful tools for the characterization of polymers. TGA and DSC provide die information about polymer stability upon heating and thermal behaviors of polymers. Most of the polymers syndiesized via transition metal coupling are conjugated polymers. They are relatively stable upon heating and have higher Tgs. [Pg.490]

EB irradiation of polymeric materials leads to superior properties than the 7-ray-induced modification due to the latter having lower achievable dose rate than the former. Because of the lower dose rate, oxygen has an opportunity to diffuse into the polymer and react with the free radicals generated thus causing the greater amount of chain scissions. EB radiation is so rapid that there is insufficient time for any significant amount of oxygen to diffuse into the polymer. Stabilizers (antirads) reduce the dose-rate effect [74]. Their effectiveness depends on the abUity to survive irradiation and then to act as an antioxidant in the absence of radiation. [Pg.863]

The polymer stability upon storage was tested by keeping samples of pure, powdered poly(N-palmitoylhydroxyproline ester) in... [Pg.205]

Electro-optic materials can be made using liquid crystal polymer combinations. In these applications, termed polymer-stabilized liquid crystals [83,86], the hquid crystal is not removed after polymerization of the monomer and the resulting polymer network stabilizes the liquid crystal orientation. [Pg.541]

X represents the combined number of both types of units in the polymer chain. Eq. (3) applies also to polymers stabilized (see Chap. Ill) with small amounts of monofunctional units, although here it becomes necessary to replace the extent of reaction p with another quantity, namely, the probability that a given functional group has reacted with a bifunctional monomer. Type ii polymers stabilized with an excess of one or the other ingredient will be discussed later. [Pg.320]

A similar polymer-stabilized colloidal system is described by James and coworkers [66]. Rhodium colloids are obtained by reducing RhCls, 3H2O with ethanol in the presence of PVP. The monophasic hydrogenation of various substrates such as benzyl acetone and 4-propylphenol and benzene derivatives was performed under mild conditions (25 °C and 1 bar H2). The nanoparticles are poorly characterized and benzyl acetone is reduced with 50 TTO in 43 h. [Pg.267]

It is well known that the trimeric phosphonitri-lic chloride can be polymerized, at 200-300°C, to poly(dichlorophosphazene) (1), hereafter this polymer will be referred to as chloropolymer. Since this polymer contains hydrolytically-unstable chlorine groups, these groups are usually replaced with various alcohols, phenols, or amines to import the polymer stability. In our laboratories, the substitution is generally with alcohols or phenols. The reaction scheme is shown in Figure 1. [Pg.255]

Scheme 5. Covalent attachment to an amino-functionalized gel of pre-formed, polymer-stabilized metal (Rh, Pt) nanoparticles. (Reprinted from Ref. [33], 1991, with permission from the American chemical Society.)... Scheme 5. Covalent attachment to an amino-functionalized gel of pre-formed, polymer-stabilized metal (Rh, Pt) nanoparticles. (Reprinted from Ref. [33], 1991, with permission from the American chemical Society.)...
Formation of Missing Au SC via Thiolation of Polymer-Stabilized Gold Clusters... [Pg.379]


See other pages where Polymer stabilization stabilizers is mentioned: [Pg.314]    [Pg.304]    [Pg.789]    [Pg.789]    [Pg.318]    [Pg.204]    [Pg.128]    [Pg.128]    [Pg.299]    [Pg.200]    [Pg.200]    [Pg.716]    [Pg.488]    [Pg.116]    [Pg.117]    [Pg.117]    [Pg.117]    [Pg.118]    [Pg.335]    [Pg.337]    [Pg.488]    [Pg.23]    [Pg.150]    [Pg.347]    [Pg.478]    [Pg.480]    [Pg.197]    [Pg.76]    [Pg.917]    [Pg.269]    [Pg.35]    [Pg.224]    [Pg.344]    [Pg.344]    [Pg.374]   
See also in sourсe #XX -- [ Pg.258 , Pg.259 , Pg.261 ]

See also in sourсe #XX -- [ Pg.398 ]




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Acrylic polymers stability

Adsorbing Polymers Bridging Flocculation and Steric Stabilization

Amphipathic polymers, steric stabilization

Analytical Techniques in Polymer Stability Studies

Approaches to Polymer Stabilization

Biocompatibility polymer stability

Biodegradable polymer nanocomposite thermal stability

Catalysts polymer stabilized

Chemical stabilization of conducting polymers

Clay-polymer nanocomposites thermal stability

Colloids stabilization, polymer adsorption

Conducting polymers chemical stabilization

Conducting polymers mechanical stability

Conducting polymers stability

Conducting polymers stabilization

Coordination polymers oxidative stability

Coordination polymers thermal stability

Copper polymer-stabilized

Decoherence theory polymer conformational stability, transitions

Dimensional stability wood-polymer composites

Dimensional stability, liquid crystal polymers

Dispersion stability, polymer particles

Divanadium, polymer-stabilized

EVERSORB 90 UV Stabilizer for Polymers

EVERSORB 91 Light Stabilizer for Polymers

Effect of Polymers on Colloid Stability

Electrically active polymers stability

Electronic polymers stability

Electrostatic and Polymer-Induced Colloid Stability

Emulsion stability polymer

Emulsions, freeze/thaw stability polymer

Environmental Stability of Polymers

FERRO UV-CHEK Light Stabilizers for Polymers

Factors Affecting the Stability of Polymer Thin Films

Factors Controlling Stability of Polymers Acceptable for Gas Sensor Application

Flame retardance stabilization, polymer

Flammability and thermal stability of polymer layered silicate nanocomposites

Flat-panel displays, polymer stabilized

Flat-panel displays, polymer stabilized liquid crystals

Formation and Stability of Polymer Chelates

Free polymer effect, emulsion stability

Guest-host polymers phase stability

Heat-resistant polymers thermal stability

High-temperature, oxidative stability polymers

Hindered amine light stabilizers polymer weathering

Hindered amine light stabilizers polymers

Hindered amine stabilizers polymers

Hydrocarbon polymers, stability

Hydrolytic stability 242 Polymer Characterization

Hydrophobically associating polymer thermal stability

Influence of Polymers on Colloidal Stability

Inorganic particle-polymer thermal stability

Inorganic polymers, stability

Interpenetrating polymer networks stabilization

Latex polymer, stability

Mechanical stability high molecular weight synthetic polymers

Mechanical stability of polymers

Melt stabilization, polymers

Melt stabilizers 606 High Performance Polymers

Monomer Conversion, Shortstop and Stabilization of Polymers

Monomer stabilization polymer stabilizers

Nanoreactors polymer-stabilized

Network stabilized liquid crystals polymer dispersions

Nitroxyl radicals polymer stabilization

Optically Tunable Diffraction Gratings in Polymer-Stabilized Liquid Crystals

Orientation stability polymer glass transition temperature

Oxidative stability of polymers

Oxyluminescence in Polymer Stabilizer Studies

POLYMER ADSORPTION AND DISPERSION STABILITY

Perfluoroalkoxy polymers stabilization

Phenolic polymer stabilizers

Phospholipid-stabilized emulsions polymers

Photooxidation, polymer coating stabilization

Polymer Degradation and Stability

Polymer Film Coating to Stabilize Liquid-Junction Photovoltaic Cells

Polymer Stability and Charcoal Production

Polymer UV stabilization

Polymer adsorption and colloid stability

Polymer adsorption effect, stability

Polymer clay stabilizers, permeability

Polymer conformational stability, transitions

Polymer cross-linking thermal stability

Polymer latices stabilization

Polymer network stabilized liquid

Polymer network stabilized liquid crystal phase

Polymer particles stability

Polymer processing oxygen stabilization

Polymer product analysis/characterization stability

Polymer properties thermal stability

Polymer solution stability

Polymer stability

Polymer stability biological degradation

Polymer stability chemical degradation

Polymer stability, different species

Polymer stability, discussion

Polymer stabilization

Polymer stabilization

Polymer stabilization antioxidants

Polymer stabilization antiozonants

Polymer stabilization approaches

Polymer stabilization chemical resistance stabilizers

Polymer stabilization copolymerization

Polymer stabilization degradation chemistry

Polymer stabilization degradation mechanisms

Polymer stabilization fire retardants

Polymer stabilization hydrolysis

Polymer stabilization interactions with other additives

Polymer stabilization light stabilizers

Polymer stabilization long-term heat stability

Polymer stabilization overview

Polymer stabilization photolysis

Polymer stabilization photooxidation

Polymer stabilization photooxidation protection

Polymer stabilization physical factors

Polymer stabilization primary antioxidants

Polymer stabilization processing stability

Polymer stabilization quenchers

Polymer stabilization rational synthesis

Polymer stabilization secondary antioxidants

Polymer stabilization stabilizer activity

Polymer stabilization stabilizers, performance

Polymer stabilization their esters

Polymer stabilization thermal degradation

Polymer stabilization thermal stabilizers

Polymer stabilization thermooxidative degradation

Polymer stabilization transformations

Polymer stabilized LCDs

Polymer stabilized LCs

Polymer stabilized cholesteric liquid

Polymer stabilized cholesteric liquid crystal

Polymer stabilized cholesteric texture

Polymer stabilized clusters

Polymer stabilized liquid

Polymer stabilized liquid crystals PSLC)

Polymer stabilizers applications

Polymer stabilizers examples

Polymer stabilizers for

Polymer stabilizers ideal properties

Polymer synthesis thermal stability

Polymer thermal stability

Polymer transistor stability

Polymer vesicles structural stability

Polymer-Stabilized Blue Phase Liquid Crystals

Polymer-Stabilized Blue Phases

Polymer-bound stabilizers

Polymer-colloid-solvent mixtures polymeric stabilization

Polymer-organoclay nanocomposites thermal stability

Polymer-solvent mixtures, stability

Polymer-stabilized

Polymer-stabilized emulsions

Polymer-stabilized liquid crystals

Polymer-stabilized liquid crystals PSLCs)

Polymer-supported phase transfer catalyst stability

Polymer/graphite nanocomposites thermal stability

Polymers UV stabilizers

Polymers and Foam Stabilization

Polymers as NP Stabilizers

Polymers as stabilizers

Polymers chemical stability

Polymers degradation/stability

Polymers electrosteric stabilization

Polymers foam stabilization

Polymers heat stabilizers

Polymers mechanical stability

Polymers oxidative stability

Polymers relative thermal stability

Polymers stability against aggregation

Polymers stabilizing colloids

Polymers steric stabilization

Polymers, and Their Complexes Used as Stabilizers for Emulsions

Polymers, burning stabilization

Polymers, degradation/stabilization

Polymers, ozone stability

Polyphenylene polymers, relative stability

Principles of polymer degradation and stabilization

Product stability, polymer characterization

Relationships between enhanced thermal stability of polymer-clay nanocomposites and flame retardancy

STABILIZATION AND DEGRADATION OF POLYMERS

STABILIZATION OF POLYMERS AND STABILIZER PROCESSES

Semi-interpenetrating polymer networks stabilization

Silicone-containing polymers stability

Solid-phase polymer stability

Solvent effects polymer coating stabilization

Stability evaluation, polymer weathering

Stability highly conductive polymer electrolyte

Stability lithium polymer batteries

Stability of Colloid-Polymer Mixtures

Stability of Electrically Conducting Polymers

Stability of conjugated polymers

Stability of polymer electrolyte-based dye-sensitized solar cells

Stability of polymer solutions

Stability of polymers

Stability polymer factors controlling

Stability, polymer blends

Stabilization by polymers

Stabilization kinetics, polymer coatings

Stabilization methods (polymeric styrenic polymers

Stabilization of Individual Polymers

Stabilization of Polymer Colloid Dispersions

Stabilization of Polymer Systems

Stabilization of Selected Polymers

Stabilization of commercial polymers

Stabilization of polymers

Stabilization of polymers against photodegradation

Stabilized homo polymers

Stabilizer polymer

Stabilizer polymer

Stabilizer polymer dispersions

Stabilizer polymer homogeneous dispersion

Stabilizer polymer polymerization

Stabilizer polymer-type

Stabilizers polymer-supported

Stabilizers soils, polymers

Stabilizers, polymers containing

Stabilizing polymers

Stabilizing polymers

Sterically Stabilized Colloidal Boehmite Rods Polymer

Straight-chain polymer stability

Styrenic polymers, stabilization methods

Sulfonated polymers, thermal stability

Supramolecular stabilization polymers

Synthesis Using Polymer Stabilizers

Synthesis polymer stabilizers

Synthetic polymer catalysts stability

Temporal and thermal stabilities of polymers nanostructured with cyclodextrins

The Effect of Antioxidants and Polymer Stabilizers

Thermal Stability and Processing of Renewable Polymers

Thermal stability polymer structure

Thermal stability, polymer hydroxides

Thermal stability, polysaccharide polymers

Thermal stability/stabilization polymer nanocomposites

Thermal stabilizers for halogenated polymers and their copolymers

Thermogravimetry polymer stability

Toxicity polymer stabilizers

Transition metal catalysts polymer supported, stability

UV stabilization of polymers

Ultraviolet light stability polymers

Ultraviolet radiation polymer coating stabilization

Unbranched polymers, stability

Vinylidene chloride polymers stabilization

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