Polymerization
In chemical compounds, polymerization can occur via a variety of reaction mechanisms that vary in complexity due to the functional groups present in the reactants[3] and their inherent steric effects.[3] As alkenes can polymerize in somewhat straightforward radical reactions, they form useful compounds such as polyethylene and polyvinyl chloride (PVC),[3] which are produced in high tonnages each year[3] due to their usefulness in manufacturing processes of commercial products, such as piping, insulation and packaging.[6][7] Step-growth polymers are formed by independent reaction steps between functional groups of monomer units, usually containing heteroatoms such as nitrogen or oxygen.For example, polyester chains grow by reaction of alcohol and carboxylic acid groups to form ester links with loss of water.Chain-growth polymerization is involved in the manufacture of polymers such as polyethylene, polypropylene, polyvinyl chloride (PVC), and acrylate.A related issue is temperature control, also called heat management, during these reactions, which are often highly exothermic.Although the polymer dispersity and molecular weight may be improved, these methods may introduce additional processing requirements to isolate the product from a solvent.
ArchitectureTacticityDegradationMark–Houwink theoryFlory–Huggins solution theoryCoil–globule transitionRadical polymerizationNitroxide-mediated radical polymerizationStep polymerizationCondensation polymerizationAddition polymerizationClassificationPolyolefinPolyethylenePolypropylenePolyisobutylenePolyurethanePolyesterPolycarbonateVinyl polymersPolystyreneHomopolymerCopolymerHydrogelsSelf-healing hydrogelsCharacterizationX-ray crystallographyRheologyRheometryViscometryHeegerMacDiarmidShirakawa Edwardsde GennesZieglerStaudingerGoodyearBaekelandHaywardBraconnotExtrusionBlow moldingApplied coatingsProtective Coatings3D printingConsumer productsWhitewallsCookware and bakewareBakeliteFood ContainerVinyl recordKevlarPlastic bottlePlastic bagpolymer chemistryAmerican EnglishBritish Englishmonomer moleculeschemical reactionpolymerchemical compoundsfunctional groupssteric effectsalkenesradical reactionscarbonyl groupstyrenepolyvinyl chloridecopolymersformaldehydetrimerscyclizetetramersoligomersnucleophilichemiacetalautoaccelerationStep-growth polymerizationheteroatomscondensation polymersalcoholcarboxylic acidpolyurethanesisocyanateaddition polymersChain-growth polymerizationfree radicalcationdouble bondsacrylatecationic addition polymerizationanionic addition polymerizationliving polymerizationZiegler–Natta polymerizationpolymer branchingethylenetemperature controlemulsion polymerizationsolution polymerizationsuspension polymerizationprecipitation polymerizationdispersityPhotopolymerstereolithographydigital micromirror deviceCross-linkEnzymatic polymerizationIn situ polymerizationMetallocenePlasma polymerizationPolymer characterizationPolymer physicsReversible addition−fragmentation chain-transfer polymerizationRing-opening polymerizationSequence-controlled polymersSol-gelUllmann's Encyclopedia of Industrial ChemistryBibcode