monomer

monomer
monomeric /mon'euh mer"ik/, adj.
/mon"euh meuhr/, n. Chem.
a molecule of low molecular weight capable of reacting with identical or different molecules of low molecular weight to form a polymer.
[1910-15; MONO- + -MER]

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Molecule of any of a class of mostly organic compounds that can react with other molecules of the same or other compounds to form very large molecules (polymers).

The essential feature of monomer molecules is the ability to form chemical bonds (see bonding) with at least two other monomer molecules (polyfunctionality). Those able to react with two others can form only chainlike polymers; those able to react with three or more can form cross-linked, network polymers. Examples of monomers (and their polymers) are styrene (polystyrene), ethylene (polyethylene), and amino acids (proteins).

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 a molecule of any of a class of compounds, mostly organic, that can react with other molecules of the same or other compound to form very large molecules, or polymers. The essential feature of a monomer is polyfunctionality, the capacity to form chemical bonds to at least two other monomer molecules. Bifunctional monomers can form only linear, chainlike polymers, but monomers of higher functionality yield cross-linked, network polymeric products.

      Addition reactions are characteristic of monomers that contain either a double bond between two atoms or a ring of from three to seven atoms; examples include styrene, caprolactam (which forms nylon-6), and butadiene and acrylonitrile (which copolymerize to form the synthetic rubber Buna N). Condensation polymerizations are typical of monomers containing two or more reactive atomic groupings; e.g., a compound that is both an alcohol and an acid can undergo repetitive ester formation involving the alcohol group of each molecule with the acid group of the next, to form a long-chain polyester. Similarly, hexamethylenediamine, which contains two amine groups, condenses with adipic acid, which contains two acid groups, to form the polymer nylon-6,6.

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Universalium. 2010.

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Look at other dictionaries:

  • monomer — MONOMÉR, monomeri, s.m. Substanţă chimică simplă, de obicei organică, cu greutate moleculară mică şi cu caracter instabil, care intră în constituţia unui polimer. – Din fr. monomère. Trimis de LauraGellner, 04.06.2004. Sursa: DEX 98  monomér s.… …   Dicționar Român

  • monomer — mon o*mer, n. (Chem.) The basic conceptual building unit of a polymer; a molecule of low molecular weight which may combine with other molecules to form a molecule in a chain or branched form having high molecular weight; as, amino acids are the… …   The Collaborative International Dictionary of English

  • monomer — monomer. См. мономер. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • monomer — (n.) 1914, from MONO (Cf. mono ) + Gk. meros part (see MERIT (Cf. merit) (n.)). Related: Monomerous …   Etymology dictionary

  • monomer — monòmēr m <G monoméra> DEFINICIJA kem. osnovna konstitucijska jedinica polimera …   Hrvatski jezični portal

  • monomer — ► NOUN Chemistry ▪ a molecule that can be linked to other identical molecules to form a polymer …   English terms dictionary

  • monomer — [män′ə mər] n. [ MONO + Gr meros, a part: see MERIT] a simple molecule that can form polymers by combining with identical or similar molecules monomeric [män′əmer′ik] adj …   English World dictionary

  • Monomer — A monomer (from Greek mono one and meros part ) is an atom or a small molecule that may bind chemically to other monomers to form a polymer[1]; the term monomeric protein may also be used to describe one of the proteins making up a multiprotein… …   Wikipedia

  • Monomer — Monomere (altgriechisch μόνος mono ein, einzel μέρος meros Teil, Anteil ) sind niedermolekulare, reaktionsfähige Moleküle, die sich zu molekularen Ketten oder Netzen, zu unverzweigten oder verzweigten Polymeren, zusammenschließen können. Im… …   Deutsch Wikipedia

  • monomer — mo|no|mer 〈Adj.; Chem.〉 aus einzelnen Molekülen bestehend; Ggs polymer [<grch. monos „allein“ + meros „Teil“] * * * mo|no|mer [↑ mono u. ↑ mer] nennt man ein Teilchen (Atom, Molekül) mit dem Einfachen der Molmasse (z. B. HgCl, NO2, H2C=CH2),… …   Universal-Lexikon

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