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Polymer degradation

Index Polymer degradation

Polymer degradation is a change in the properties—tensile strength, color, shape, etc.—of a polymer or polymer-based product under the influence of one or more environmental factors such as heat, light or chemicals such as acids, alkalis and some salts. [1]

107 relations: Acid, Alkali, Allotropes of oxygen, Allyl group, Anode, Antioxidant, Applied spectroscopy, Arrhenius plot, Atom, Base (chemistry), Biodegradable plastic, Biodegradation, Carbon dioxide, Carbon fiber reinforced polymer, Carbon fibers, Carbon monoxide, Carbonate, Carbonyl group, Cathode, Celsius, Chain-growth polymerization, Chemical structure, Chemical substance, Chlorine, Color, Composite material, Compost, Copper, Corrosion, Cross-link, Crutch, Elastomer, Electric battery, Electrode, Electromagnetic radiation, Environmental stress cracking, Environmental stress fracture, Extrusion, Forensic engineering, Forensic materials engineering, Forensic polymer engineering, Gamma ray, Gasification, Hard water, Heat, Hindered amine light stabilizers, Hydrogen, Hydrogen chloride, Hydrogenation, Hydrolysis, ..., Hydroxide, Infrared spectroscopy, Injection moulding, Iron, Light, Maleimide, Microorganism, Molecular mass, Molecule, Monomer, Natural rubber, Nitrile rubber, Noble metal, Nylon, Oxygen, Ozone, Ozone cracking, Parts-per notation, PH, Photodissociation, Pollution, Poly(methyl methacrylate), Polyamide, Polybutadiene, Polybutylene, Polycarbonate, Polyester, Polyethylene, Polyethylene terephthalate, Polyimide, Polymer, Polymer engineering, Polyolefin, Polyoxymethylene, Polypropylene, Polystyrene, Polyvinyl chloride, Pyrolysis, Radical (chemistry), Recycling, Redox, Salt (chemistry), Solvolysis, Step-growth polymerization, Stress corrosion cracking, Styrene-butadiene, Tertiary carbon, Thermal decomposition, Tire, Triazine, Ultimate tensile strength, Ultraviolet, UV degradation, Vulcanization, Water, Weather testing of polymers, X-ray. Expand index (57 more) »

Acid

An acid is a molecule or ion capable of donating a hydron (proton or hydrogen ion H+), or, alternatively, capable of forming a covalent bond with an electron pair (a Lewis acid).

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Alkali

In chemistry, an alkali (from Arabic: al-qaly “ashes of the saltwort”) is a basic, ionic salt of an alkali metal or alkaline earth metal chemical element.

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Allotropes of oxygen

There are several known allotropes of oxygen.

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Allyl group

An allyl group is a substituent with the structural formula H2C.

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Anode

An anode is an electrode through which the conventional current enters into a polarized electrical device.

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Antioxidant

Antioxidants are molecules that inhibit the oxidation of other molecules.

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Applied spectroscopy

Applied spectroscopy is the application of various spectroscopic methods for detection and identification of different elements/compounds in solving problems in the fields of forensics, medicine, oil industry, atmospheric chemistry, pharmacology, etc.

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Arrhenius plot

In chemical kinetics, an Arrhenius plot displays the logarithm of a reaction rate constant, (\ln(k), ordinate axis) plotted against inverse temperature (1/T, abscissa).

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Atom

An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element.

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Base (chemistry)

In chemistry, bases are substances that, in aqueous solution, release hydroxide (OH−) ions, are slippery to the touch, can taste bitter if an alkali, change the color of indicators (e.g., turn red litmus paper blue), react with acids to form salts, promote certain chemical reactions (base catalysis), accept protons from any proton donor, and/or contain completely or partially displaceable OH− ions.

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Biodegradable plastic

Biodegradable plastics are plastics that are decomposed by the action of living organisms, usually bacteria.

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Biodegradation

Biodegradation is the disintegration of materials by bacteria, fungi, or other biological means.

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Carbon dioxide

Carbon dioxide (chemical formula) is a colorless gas with a density about 60% higher than that of dry air.

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Carbon fiber reinforced polymer

Carbon fiber reinforced polymer, carbon fiber reinforced plastic or carbon fiber reinforced thermoplastic (CFRP, CRP, CFRTP or often simply carbon fiber, carbon composite or even carbon), is an extremely strong and light fiber-reinforced plastic which contains carbon fibers.

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Carbon fibers

Carbon fibers or carbon fibres (alternatively CF, graphite fiber or graphite fibre) are fibers about 5–10 micrometers in diameter and composed mostly of carbon atoms.

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Carbon monoxide

Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air.

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Carbonate

In chemistry, a carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula of.

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Carbonyl group

In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C.

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Cathode

A cathode is the electrode from which a conventional current leaves a polarized electrical device.

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Celsius

The Celsius scale, previously known as the centigrade scale, is a temperature scale used by the International System of Units (SI).

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Chain-growth polymerization

Chain-growth polymerization or chain polymerization (IUPAC recommended term) is a polymerization mechanism in which monomer molecules add onto the active site of a growing polymer chain one at a time.

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Chemical structure

A chemical structure determination includes a chemist's specifying the molecular geometry and, when feasible and necessary, the electronic structure of the target molecule or other solid.

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Chemical substance

A chemical substance, also known as a pure substance, is a form of matter that consists of molecules of the same composition and structure.

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Chlorine

Chlorine is a chemical element with symbol Cl and atomic number 17.

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Color

Color (American English) or colour (Commonwealth English) is the characteristic of human visual perception described through color categories, with names such as red, orange, yellow, green, blue, or purple.

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Composite material

A composite material (also called a composition material or shortened to composite, which is the common name) is a material made from two or more constituent materials with significantly different physical or chemical properties that, when combined, produce a material with characteristics different from the individual components.

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Compost

Compost is organic matter that has been decomposed in a process called composting.

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Copper

Copper is a chemical element with symbol Cu (from cuprum) and atomic number 29.

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Corrosion

Corrosion is a natural process, which converts a refined metal to a more chemically-stable form, such as its oxide, hydroxide, or sulfide.

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Cross-link

A cross-link is a bond that links one polymer chain to another.

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Crutch

A crutch is a mobility aid that transfers weight from the legs to the upper body.

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Elastomer

An elastomer is a polymer with viscoelasticity (i. e., both viscosity and elasticity) and very weak intermolecular forces, and generally low Young's modulus and high failure strain compared with other materials.

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Electric battery

An electric battery is a device consisting of one or more electrochemical cells with external connections provided to power electrical devices such as flashlights, smartphones, and electric cars.

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Electrode

An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or air).

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Electromagnetic radiation

In physics, electromagnetic radiation (EM radiation or EMR) refers to the waves (or their quanta, photons) of the electromagnetic field, propagating (radiating) through space-time, carrying electromagnetic radiant energy.

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Environmental stress cracking

Environmental Stress Cracking (ESC) is one of the most common causes of unexpected brittle failure of thermoplastic (especially amorphous) polymers known at present.

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Environmental stress fracture

In materials science, environmental stress fracture or environment assisted fracture is the generic name given to premature failure under the influence of tensile stresses and harmful environments of materials such as metals and alloys, composites, plastics and ceramics.

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Extrusion

Extrusion is a process used to create objects of a fixed cross-sectional profile.

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Forensic engineering

Forensic engineering has been defined as "the investigation of failures - ranging from serviceability to catastrophic - which may lead to legal activity, including both civil and criminal". It therefore includes the investigation of materials, products, structures or components that fail or do not operate or function as intended, causing personal injury, damage to property or economic loss.

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Forensic materials engineering

Forensic materials engineering, a branch of forensic engineering, focuses on the material evidence from crime or accident scenes, seeking defects in those materials which might explain why an accident occurred, or the source of a specific material to identify a criminal.

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Forensic polymer engineering

Forensic polymer engineering is the study of failure in polymeric products.

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Gamma ray

A gamma ray or gamma radiation (symbol γ or \gamma), is penetrating electromagnetic radiation arising from the radioactive decay of atomic nuclei.

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Gasification

Gasification is a process that converts organic- or fossil fuel-based carbonaceous materials into carbon monoxide, hydrogen and carbon dioxide.

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Hard water

Hard water is water that has high mineral content (in contrast with "soft water").

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Heat

In thermodynamics, heat is energy transferred from one system to another as a result of thermal interactions.

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Hindered amine light stabilizers

Hindered amine light stabilizers (HALS) are chemical compounds containing an amine functional group that are used as stabilizers in plastics and polymers.

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Hydrogen

Hydrogen is a chemical element with symbol H and atomic number 1.

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Hydrogen chloride

The compound hydrogen chloride has the chemical formula and as such is a hydrogen halide.

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Hydrogenation

Hydrogenation – to treat with hydrogen – is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum.

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Hydrolysis

Hydrolysis is a term used for both an electro-chemical process and a biological one.

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Hydroxide

Hydroxide is a diatomic anion with chemical formula OH−.

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Infrared spectroscopy

Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) involves the interaction of infrared radiation with matter.

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Injection moulding

Injection moulding (British English) or injection molding (American English) is a manufacturing process for producing parts by injecting molten material into a mould.

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Iron

Iron is a chemical element with symbol Fe (from ferrum) and atomic number 26.

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Light

Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum.

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Maleimide

Maleimide is a chemical compound with the formula H2C2(CO)2NH (see diagram).

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Microorganism

A microorganism, or microbe, is a microscopic organism, which may exist in its single-celled form or in a colony of cells. The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from 6th century BC India and the 1st century BC book On Agriculture by Marcus Terentius Varro. Microbiology, the scientific study of microorganisms, began with their observation under the microscope in the 1670s by Antonie van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera and anthrax. Microorganisms include all unicellular organisms and so are extremely diverse. Of the three domains of life identified by Carl Woese, all of the Archaea and Bacteria are microorganisms. These were previously grouped together in the two domain system as Prokaryotes, the other being the eukaryotes. The third domain Eukaryota includes all multicellular organisms and many unicellular protists and protozoans. Some protists are related to animals and some to green plants. Many of the multicellular organisms are microscopic, namely micro-animals, some fungi and some algae, but these are not discussed here. They live in almost every habitat from the poles to the equator, deserts, geysers, rocks and the deep sea. Some are adapted to extremes such as very hot or very cold conditions, others to high pressure and a few such as Deinococcus radiodurans to high radiation environments. Microorganisms also make up the microbiota found in and on all multicellular organisms. A December 2017 report stated that 3.45 billion year old Australian rocks once contained microorganisms, the earliest direct evidence of life on Earth. Microbes are important in human culture and health in many ways, serving to ferment foods, treat sewage, produce fuel, enzymes and other bioactive compounds. They are essential tools in biology as model organisms and have been put to use in biological warfare and bioterrorism. They are a vital component of fertile soils. In the human body microorganisms make up the human microbiota including the essential gut flora. They are the pathogens responsible for many infectious diseases and as such are the target of hygiene measures.

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Molecular mass

Relative Molecular mass or molecular weight is the mass of a molecule.

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Molecule

A molecule is an electrically neutral group of two or more atoms held together by chemical bonds.

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Monomer

A monomer (mono-, "one" + -mer, "part") is a molecule that "can undergo polymerization thereby contributing constitutional units to the essential structure of a macromolecule".

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Natural rubber

Natural rubber, also called India rubber or caoutchouc, as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds, plus water.

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Nitrile rubber

Nitrile rubber, also known as NBR, Buna-N, and acrylonitrile butadiene rubber, is a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene.

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Noble metal

In chemistry, the noble metals are metals that are resistant to corrosion and oxidation in moist air (unlike most base metals).

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Nylon

Nylon is a generic designation for a family of synthetic polymers, based on aliphatic or semi-aromatic polyamides.

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Oxygen

Oxygen is a chemical element with symbol O and atomic number 8.

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Ozone

Ozone, or trioxygen, is an inorganic molecule with the chemical formula.

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Ozone cracking

Cracks can be formed in many different elastomers by ozone attack, and the characteristic form of attack of vulnerable rubbers is known as ozone cracking.

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Parts-per notation

In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction.

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PH

In chemistry, pH is a logarithmic scale used to specify the acidity or basicity of an aqueous solution.

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Photodissociation

Photodissociation, photolysis, or photodecomposition is a chemical reaction in which a chemical compound is broken down by photons.

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Pollution

Pollution is the introduction of contaminants into the natural environment that cause adverse change.

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Poly(methyl methacrylate)

Poly(methyl methacrylate) (PMMA), also known as acrylic or acrylic glass as well as by the trade names Crylux, Plexiglas, Acrylite, Lucite, and Perspex among several others (see below), is a transparent thermoplastic often used in sheet form as a lightweight or shatter-resistant alternative to glass.

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Polyamide

A polyamide is a macromolecule with repeating units linked by amide bonds.

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Polybutadiene

Polybutadiene is a synthetic rubber.

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Polybutylene

Polybutylene (polybutene-1, poly(1-butene), PB-1) is a polyolefin or saturated polymer with the chemical formula (C4H8)n.

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Polycarbonate

Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate groups in their chemical structures.

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Polyester

Polyester is a category of polymers that contain the ester functional group in their main chain.

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Polyethylene

Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(ethylene)) is the most common plastic.

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Polyethylene terephthalate

Polyethylene terephthalate (sometimes written poly(ethylene terephthalate)), commonly abbreviated PET, PETE, or the obsolete PETP or PET-P, is the most common thermoplastic polymer resin of the polyester family and is used in fibres for clothing, containers for liquids and foods, thermoforming for manufacturing, and in combination with glass fibre for engineering resins.

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Polyimide

Polyimide (sometimes abbreviated PI) is a polymer of imide monomers.

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Polymer

A polymer (Greek poly-, "many" + -mer, "part") is a large molecule, or macromolecule, composed of many repeated subunits.

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Polymer engineering

Polymer engineering is generally an engineering field that designs, analyses, or modifies polymer materials.

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Polyolefin

A polyolefin is any of a class of polymers produced from a simple olefin (also called an alkene with the general formula CnH2n) as a monomer.

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Polyoxymethylene

Polyoxymethylene (POM), also known as acetal, polyacetal, and polyformaldehyde, is an engineering thermoplastic used in precision parts requiring high stiffness, low friction, and excellent dimensional stability.

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Polypropylene

Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications.

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Polystyrene

Polystyrene (PS) is a synthetic aromatic hydrocarbon polymer made from the monomer styrene.

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Polyvinyl chloride

Polyvinyl chloride, also known as polyvinyl or '''vinyl''', commonly abbreviated PVC, is the world's third-most widely produced synthetic plastic polymer, after polyethylene and polypropylene.

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Pyrolysis

Pyrolysis is the thermal decomposition of materials at elevated temperatures in an inert atmosphere.

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Radical (chemistry)

In chemistry, a radical (more precisely, a free radical) is an atom, molecule, or ion that has an unpaired valence electron.

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Recycling

Recycling is the process of converting waste materials into new materials and objects.

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Redox

Redox (short for reduction–oxidation reaction) (pronunciation: or) is a chemical reaction in which the oxidation states of atoms are changed.

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Salt (chemistry)

In chemistry, a salt is an ionic compound that can be formed by the neutralization reaction of an acid and a base.

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Solvolysis

Solvolysis is a type of nucleophilic substitution (SN1) /(SN2) or elimination, where the nucleophile is a solvent molecule.

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Step-growth polymerization

Step-growth polymerization refers to a type of polymerization mechanism in which bi-functional or multifunctional monomers react to form first dimers, then trimers, longer oligomers and eventually long chain polymers.

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Stress corrosion cracking

Stress corrosion cracking (SCC) is the growth of crack formation in a corrosive environment.

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Styrene-butadiene

Styrene-butadiene or styrene-butadiene rubber (SBR) describe families of synthetic rubbers derived from styrene and butadiene (the version developed by Goodyear is called Neolite).

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Tertiary carbon

A tertiary carbon atom is a carbon atom bound to three other carbon atoms.

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Thermal decomposition

Thermal decomposition, or thermolysis, is a chemical decomposition caused by heat.

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Tire

A tire (American English) or tyre (British English; see spelling differences) is a ring-shaped component that surrounds a wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide traction on the surface traveled over.

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Triazine

A triazine is class of nitrogen-containing heterocycles.

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Ultimate tensile strength

Ultimate tensile strength (UTS), often shortened to tensile strength (TS), ultimate strength, or Ftu within equations, is the capacity of a material or structure to withstand loads tending to elongate, as opposed to compressive strength, which withstands loads tending to reduce size.

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Ultraviolet

Ultraviolet (UV) is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays.

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UV degradation

Many natural and synthetic polymers are attacked by ultraviolet radiation, and products using these materials may crack or disintegrate if they are not UV-stable.

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Vulcanization

Vulcanization or vulcanisation is a chemical process for converting natural rubber or related polymers into more durable materials by heating them with sulfur or other equivalent curatives or accelerators.

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Water

Water is a transparent, tasteless, odorless, and nearly colorless chemical substance that is the main constituent of Earth's streams, lakes, and oceans, and the fluids of most living organisms.

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Weather testing of polymers

Weather testing of polymers is the controlled polymer degradation and polymer coating degradation under lab or natural conditions.

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X-ray

X-rays make up X-radiation, a form of electromagnetic radiation.

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References

[1] https://en.wikipedia.org/wiki/Polymer_degradation

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