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Degradation polymers

Polymer degradation is a change in the properties—tensile strength, color, shape, conductivity, etc.— of a polymer or polymer-based product under the influence of one or more environmental factors such as heat, light, and chemicals. Degradation agents and polymers most susceptible to their influence are given in Table 19.1. [Pg.249]

Korotcenkov, Handbook of Gas Sensor Materials, Integrated Analytical Systems, [Pg.249]

19 Factors Controlling Stability of Polymers Acceptable for Gas Sensor Application [Pg.250]

Degradation agent Most susceptible polymer types Examples [Pg.250]

Acids and bases Heterochain polymers Polyesters, polyurethanes [Pg.250]

In order to control polyester degradation, we must understand the processes involved in how polyesters degrade. The following section presents a brief summary of degradation mechanisms that are involved. [Pg.593]

The next step in developing controlled degradation polyester is to understand expectations for specific product applications. Some questions to be answered include the following  [Pg.593]

Individual assessment of specific application factors indicate the key factors for selecting a specific polymer. [Pg.593]

Similarly to polymer synthesis, there are essentially two main mechanisms of degradation of synthetic polymers involving main chain links and leading to [Pg.58]

In random degradation molecular mass decreases early, while in chain degradation the molecular mass of the polymer remains almost constant. Characterisation methods for molecular mass are thus very sensitive methods to follow random degradation. In contrast, as monomer is produced in chain depolymerisation, weight loss measurement techniques are the best methods to follow this kind of degradation. (Chapters 10-12, in Section IV, of this book focus on the methods used in the molecular characterisation and analysis of polymer degradation and polymer degradation mechanisms.) [Pg.59]

Monomer concentration increases steadily throughout the reaction [Pg.59]

High molecular masses remain all the along reaction [Pg.59]

The longer the reaction time, the higher the yield in monomer [Pg.59]

The annual increase in the number of papers devoted to photo-induced breakdown of polymers is such that in compiling a review of the field covering approximately two years some choice must be made of the papers to be included. Two aspects of photo-degradation appear frequently in patents - stabilization and accelerated decomposition. While both fields have seen some interesting developments this type of publication has not been included in this review. [Pg.370]


Other aspects of stabilization of acetal resins are briefly discussed under processing and fabrication. Reference 15 provides a more detailed discussion of the mechanism of polymer degradation. [Pg.57]

Boron also reacts with hydroxyl-containing polymers such as cellulose. When exposed to a flame the boron and hydroxyl groups form a glassy ester that coats the substrate and reduces polymer degradation. A similar type of action has been observed in the boron—alumina tfihydrate system. [Pg.457]

Protective Coatings. Some flame retardants function by forming a protective Hquid or char barrier. These minimize transpiration of polymer degradation products to the flame front and/or act as an insulating layer to reduce the heat transfer from the flame to the polymer. Phosphoms compounds that decompose to give phosphoric acid and intumescent systems are examples of this category (see Flame retardants, phosphorus flame retardants). [Pg.465]

Two other important commercial uses of initiators are in polymer cross-linking and polymer degradation. In a cross-linking reaction, atom abstraction, usually a hydrogen abstraction, occurs, followed by termination by coupling of two polymer radicals to form a covalent cross-link ... [Pg.219]

Acid Chloride Reaction. In situations where the reactants are sensitive to high temperature or the polymer degrades before the melt poiat is reached, the acid chloride route is often used to produce the polyamide (47). The basic reaction ia the presence of a base, B , is as follows ... [Pg.224]

J. E. Rabek, Polymer Degradation Mechanisms and Experimental Methods, Chapman and HaU, London, 1995, pp. 296—306. [Pg.242]

W. Schnabel, Polymer Degradation, Hanser Publishers, Munich, Germany, 1981, pp. 154—177. [Pg.243]

Polym. Degrad. Stabil 45(2) (1994), papers from the ArdlUPAC International Sjmposium on Macromolecules, Montreal, Canada. [Pg.487]

The metabohc rate of poly(ester—amide) where x = Q has been studied in rats using carbon-14 labeled polymer. This study indicates that polymer degradation occurs as a result of hydrolysis of the ester linkages whereas the amide linkages remain relatively stable in vivo. Most of the radioactivity is excreted by urine in the form of unchanged amidediol monomer, the polymer hydrolysis product (51). [Pg.192]

R. Mazzeo, Polymer Degradation andits Prevention Especially DuringMixing, at the MCA Meeting of the 147th Rubber Division, Philadelphia, Pa., May 2—5,1995, American Chemical Society, Washington, D.C. [Pg.262]

Antiozonants (qv) prevent or reduce polymer degradation by the active ozone molecule. Some antioxidant compounds, such as the /)i7n7-phenylenediamines, are excellent as antiozonants (36). The protection by these compounds is thought to be either a reaction with the ozone before it can react with the surface of the mbber or an aid in reuniting chains severed by ozone (37). [Pg.499]

N. Grassie, ed.. Developments in Polymer Degradation, Vols. 1 and 2, AppHed Science PubHshers, London, 1977. [Pg.530]

The maximum rates of crystallisation of the more common crystalline copolymers occur at 80—120°C. In many cases, these copolymers have broad composition distributions containing both fractions of high VDC content that crystallise rapidly and other fractions that do not crystallise at all. Poly(vinyhdene chloride) probably crystallises at a maximum rate at 140—150°C, but the process is difficult to foUow because of severe polymer degradation. The copolymers may remain amorphous for a considerable period of time if quenched to room temperature. The induction time before the onset of crystallisation depends on both the type and amount of comonomer PVDC crystallises within minutes at 25°C. [Pg.432]

Most polymer degradation caused by the absorption of uv light results from radical-initiated autoxidation. [Pg.222]

Fig. 3. Mechanisms for polymer degradation. The illustration is a schematic representation of three degradation mechanisms I, cleavage of cross-links II, hydrolysis, ionisa tion, or protonation of pendent groups III, backbone cleavage. Actual biodegradation may be a combination of these mechanisms. Fig. 3. Mechanisms for polymer degradation. The illustration is a schematic representation of three degradation mechanisms I, cleavage of cross-links II, hydrolysis, ionisa tion, or protonation of pendent groups III, backbone cleavage. Actual biodegradation may be a combination of these mechanisms.
Functional dyes (1) of many types are important photochemical sensitizers for oxidation, polymerization, (polymer) degradation, isomerization, and photodynamic therapy. Often, dye stmctures from several classes of materials can fulfiH a similar technological need, and reviewing several dye stmctures... [Pg.434]

The principal mechanism of polymer degradation during aging is the acid-catalyzed cleavage of the ether linkage in the backbone. The acid acceptor. [Pg.556]


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Acrylic polymers oxidative degradation

Addition polymers degradation/biodegradation

Addition polymers environmental degradation

Addition polymers, thermal degradation

Additives that Enhance Degradation in Common Polymers

Aging and Degradation of Polymer Blends

Agriculture degradable polymers

Aliphatic polymer degradation media

Aliphatic polymers, degradation

Aliphatic polymers, degradation mechanisms

Amorphous polymers degradation

Artificial polymers degradable

Aspects of Polymer Degradation

Assessment of Biodegradable Polymers Degradability

Bacterial enzymes polymer degradation

Biochemical pathways, polymer degradation

Biodegradable polymer degradation mechanisms

Biodegradable polymer degradation rate

Biodegradable polymers degradation time

Biological Degradation of Polymers

Bioresorbable polymers modeling degradation

Bulk density polymer degradation

Bulk polymer degradation

Carbon chain polymers, abiotic degradation

Carbon-chain polymers microbial degradation

Cellulose as a platform substrate for degradable polymer synthesis

Combining the effects of polymer retention and degradation

Condensation polymers degradation/biodegradation

Condensation polymers environmental degradation

Condensation polymers thermal degradation

Controlled-degradable polymer

Crystal structures, polymers thermal degradation

DEGRADATION AND AGEING OF POLYMERS

Data Analysis of DSC Heat Effects for the Most Representative (Bio)-degradable Polymers

Degradability of Polymers in Soil

Degradable materials natural polymers

Degradable materials polymers from renewable

Degradable plastic Biodegradable polymers

Degradable plastic polymers

Degradable polymers

Degradable polymers

Degradable polymers controlled release agents

Degradable polymers in photonic applications

Degradable polymers in waste and litter control

Degradable polymers membrane-controlled release devices

Degradable polymers, fiber-optic sensors

Degradable polymers, natural

Degradable polymers, natural synthetic

Degradation and Stabilisation of Polymer

Degradation and synthesis of polymer

Degradation behavior of polymer

Degradation biodegradable polymer nanocomposite

Degradation biodegradable polymers

Degradation branched polymer architecture

Degradation controlled release polymers

Degradation green polymer chemistry

Degradation modelling polymer molecular weight

Degradation of Biodegradable Polymers

Degradation of Condensation Polymers

Degradation of Lactic Acid-based Polymers

Degradation of Polymer Nanocomposites

Degradation of Unsaturated Polymers and ADMET Polymerization

Degradation of Vinyl Polymers

Degradation of addition polymers

Degradation of chain-growth polymers

Degradation of polymer chain

Degradation of polymer matrix

Degradation of polymer solutions

Degradation of polymers

Degradation of polymers by solar radiation

Degradation of unsaturated polymers

Degradation polymer classification

Degradation polymers Polyethylene glycol)

Degradation rate of polymers

Degradation type polymer

Degradation, polymer random chain scission

Degradeable polymers

Degradeable polymers

Degraded gelatin polyme

Dextran, polymer degradation

Differential scanning calorimetry polymer degradation

Diffusion controlled reactions in polymer degradation

Disulfide-containing polymers reductive degradation

ESR as a Tool for the Study of Polymer Degradation

Effect of polymer degradation products on plasticizers

Effective diffusion coefficient polymer degradation

Enhanced degradation polymers with

Environmental degradation processes polymers

Environmental degradation, green polymer

Environmentally degradable polymer

Enzymatic Degradation of Polymers

Enzymatic degradation natural polymers

Enzymatic degradation, polymer

Enzymatically degradable polymers

Enzyme responsive polymers enzymatically degradable

Enzyme-degradable polymers

Enzymes polymer degradations

Enzymes, polymer-degrading

Equivalent circuit model degraded polymer coating

Experimental methods in polymer degradation

Experimental principles in the investigation of polymer degradation kinetics

Exploitation of Polymer Degradation

Extremely strong degradable polymers

Factors affecting aliphatic polymer degradation

Fiber-optic sensors based on degradable polymers

Flame retardance polymer degradation processes

Fluoride-vinyl polymers, degradation

Free radicals, oxidation chemistry, polymer degradation

Gene delivery polymers, degradation

General mechanism of patterned resist polymer photo-oxidative degradation

General mechanism of polymer degradation

Halide-vinyl polymers, degradation

Heterogeneous polymer degradation

Heterogeneous polymer degradation examples

Heterogeneous polymer degradation oxygen diffusion limited

High-energy radiation polymer degradation

High-performance polymers from lignin degradation products

Hydrolytic degradation of polymers

Hydrolytic degradation, polymers

Hydrolytically Degradable Polymers as Biomaterials

Hydroxyvalerate polymers bacterial degradation

Kinetics of Polymer Degradation in the Solid State

Kinetics polymer degradation

Lactic Acid-based Degradable Polymers

Light polymers readily degraded

Mechanical degradation of polymers

Mechanism of polymer chemical degradation

Mechanism polymer degradation

Mechanisms of Degradation Step Growth Polymers

Mechanisms of Polymer Degradation

Mechanisms of Thermal Degradation Chain Growth Polymers

Methacrylate polymers degradation

Microorganisms, polymer degradation

Minimizing Polymer Degradation

Models of polymer degradation

Molecular degradation products, polymers

Molecular methods polymer device degradation

Nonbiological Degradation of Polymers

On Toxics from Degradation of Polymers

Other Factors Affecting Photochemical Degradation Rates of Polymers

Oxidative degradation of polymers

Phosphorus-containing polymers thermal degradation

Photo-biodegradable polymers degradation products

Photochemical Degradation of Polymers

Photochemical Degradation of Styrenic Polymers

Photochemical polymer degradation

Photooxidation degradation of polymers

Photooxidative degradation of polymers

Photosensitized degradation of polymers

Physical pathways, polymer degradation

Poly In Degradable Polymers and Materials Khemani

Polyesters polymer degradation modelling

Polyisoprene, natural degradable polymers

Polyme degradation

Polymer Degradation Studies

Polymer Degradation and Stability

Polymer Surfaces oxidative degradation

Polymer Surfaces photochemical degradation

Polymer backbone, degradable

Polymer blends heterogeneous degradation

Polymer blends, environmentally degradable polyolefins

Polymer chain, hydrolytic degradation

Polymer controlled degradation

Polymer degradation aerobic

Polymer degradation aliphatic polyamides

Polymer degradation anaerobic

Polymer degradation and drug release

Polymer degradation bioresorbable polymers

Polymer degradation by high-energy radiation

Polymer degradation by hydrolysis

Polymer degradation cellulose

Polymer degradation chain length

Polymer degradation chemical aspects

Polymer degradation curves

Polymer degradation empirical expressions

Polymer degradation epoxy resins

Polymer degradation experimental data

Polymer degradation free radicals

Polymer degradation future trends

Polymer degradation in partly cooled reservoirs

Polymer degradation inhibition

Polymer degradation material

Polymer degradation mathematical modelling

Polymer degradation natural

Polymer degradation ozone

Polymer degradation phenolic resins

Polymer degradation photooxidation

Polymer degradation polyacrylonitrile

Polymer degradation polyester resins

Polymer degradation polyesters

Polymer degradation polyolefins

Polymer degradation processes

Polymer degradation product alkyl

Polymer degradation products

Polymer degradation protein

Polymer degradation scissions

Polymer degradation summary

Polymer degradation thermal oxidation

Polymer degradation thermoplastics

Polymer degradation thermosets

Polymer degradation, dealing with

Polymer degradation, photosensitized reactions

Polymer degradation, physical factor

Polymer degradation, rate-determining

Polymer device degradation

Polymer device degradation chain scission

Polymer device degradation functional groups

Polymer device degradation hydrolysis

Polymer device degradation methods

Polymer electrolyte fuel cells degradation

Polymer electrolyte membrane degradation, severity

Polymer electrolyte membrane fuel cell degradation analysis

Polymer nanocomposites thermal degradation pathways

Polymer networks degradation

Polymer photooxidative degradation

Polymer photosensitized degradation

Polymer product analysis/characterization degradation

Polymer radiation degradation, applications

Polymer radiation-induced degradation

Polymer stability biological degradation

Polymer stability chemical degradation

Polymer stabilization degradation chemistry

Polymer stabilization degradation mechanisms

Polymer stabilization thermal degradation

Polymer stabilization thermooxidative degradation

Polymer surface, modification, degradation

Polymer thermal oxidative degradation

Polymer-degrading bacteria

Polymers -insulating coating Degradation

Polymers Degradation in GPCSEC Columns Raniero Mendichi

Polymers Large molecules degradable

Polymers degradable, test methods

Polymers degradation analytical detection

Polymers degradation chain scission

Polymers degradation cross linking

Polymers degradation discoloration

Polymers degradation disproportionation

Polymers degradation factors affecting

Polymers degradation formation

Polymers degradation half-life

Polymers degradation initiation

Polymers degradation mechanism macroscopic properties

Polymers degradation propagation

Polymers degradation termination

Polymers degradation/stability

Polymers degrading

Polymers environmental degradation

Polymers environmentally degraded

Polymers of the degrading type

Polymers oxidative degradation

Polymers radiation degradation

Polymers thermal degradation

Polymers thermal degradation mechanisms

Polymers toxic degradation products

Polymers, burning degradation

Polymers, burning thermal degradation

Polymers, degradable, degradation

Polymers, degradable, degradation products

Polymers, degradation and stabilisation

Polymers, degradation/stabilization

Polymers, soil degradation

Polyphenols, natural degradable polymers

Polysaccharides, natural degradable polymers

Polystyrene polymer degradation

Principles of polymer degradation and stabilization

Processes in polymer degradation

Proteins, natural degradable polymers

Recycling and Degradation of Polymers

Recycling of Polymers by Thermal Degradation

Resorbable polymers degradation

Resorbable polymers polymer degradation

STABILIZATION AND DEGRADATION OF POLYMERS

Semicrystalline polymers oxidative degradation

Shape memory polymer degradable

Shear degradation polymers

Silicone polymers degradation

Siloxane polymers degradation

Solid state polymer degradation

Solvent effect polymer degradation

Step-reaction polymers, thermal degradation

Styrenic polymers photochemical degradation

Synthetic degradable polymers

Synthetic hydrophobic degradable polymers

Synthetic hydrophobic degradable polymers poly

Synthetic polymer microbial degradation

Synthetic polymers degradation

Techniques and mechanisms of polymer degradation

Temperature polymer degradation

The Polymer Degradation Process

The role of degradable polymers in agricultural systems

The science and engineering of polymer composite degradation

Thermal Analysis in the Study of Polymer (Bio) -degradation

Thermal Degradation of Chlorocarbon and Fluorocarbon Polymers

Thermal Degradation of Polymer Blends, Composites and Nanocomposites

Thermal and Thermooxidative Degradation of Reinforced Polymers

Thermal degradation of common chain-growth polymers

Thermal degradation of common step-growth polymers

Thermal degradation of methacrylic and acrylic polymers

Thermal degradation of polymers

Thermal degradation, linear polymer

Thermal degradation, linear polymer compound

Thermal degradation, synthetic polymers

Thermooxidative degradation, polymer

Thermoplastic polymers degradation resistance

To study polymer degradation

Typical Polymer Degradations during Pyrolysis

Vinyl polymer, degradation

Water-soluble, Degradable Polymers

Weathering and Degradation of Polymers

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