Lactide

Lactide

Lactide is the cyclic di-ester of lactic acid, i.e., 2-hydroxypropionic acid. Lactic acid can not form a lactone as other hydroxy acids do because the hydroxy group is too close to the carboxylic group. Instead, lactic acid first forms a dimer, which is similar to a 5-hydroxyacid. The dimer contains a hydroxy group at a convenient distance from the carboxylic group for the formation of a lactone. Indeed, the dimer readily forms a six-membered cyclic diester known as lactide.

In general, a lactide is the cyclic diester, i.e., the di-lactone of two molecules of any 2-hydroxycarboxylic acid. It can be polymerized to polylactide using suitable catalysts, with either syndiotactic or a heterotactic stereocontrol, to give materials with many useful properties.


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  • Lactide — Lac tide, n. [Lactic + anhydride.] (Chem.) A white, crystalline substance, obtained from lactic acid by distillation, and regarded as an anhydride; also, by extension, any similar substance. [1913 Webster] …   The Collaborative International Dictionary of English

  • lactide — ● lactide nom masculin Composé C6H8O4, obtenu par déshydratation cyclique de l acide lactique …   Encyclopédie Universelle

  • lactide — dilaktidas statusas T sritis chemija formulė Formulę žr. priede. priedas( ai) Grafinis formatas atitikmenys: angl. dilactide; lactide rus. дилактид; лактид ryšiai: sinonimas – laktidas sinonimas – 3,6 dimetil 1,4 dioksacikloheksan 2,5 dionas …   Chemijos terminų aiškinamasis žodynas

  • lactide — laktidas statusas T sritis chemija apibrėžtis Vidinis ciklinis esteris, susidedantis iš kelių hidroksirūgšties molekulių. atitikmenys: angl. lactide rus. лактид …   Chemijos terminų aiškinamasis žodynas

  • lactide — noun a) Any of a class of heterocyclic compounds, formally acid anhydrides, formed by heating α lactones b) The anhydride of lactic acid …   Wiktionary

  • lactide — (la kti d ) s. m. Terme de chimie. Corps qui se forme pendant la distillation sèche de l acide lactique. ÉTYMOLOGIE    Lat. lac, lait …   Dictionnaire de la Langue Française d'Émile Littré

  • lactide — lac·tide …   English syllables

  • lactide — ˈlakˌtīd, tə̇d noun ( s) Etymology: International Scientific Vocabulary lact + anhydride; probably originally formed in French 1. : a crystalline dilactone C6H8O4 formed from two molecules of lactic acid by self esterification 2 …   Useful english dictionary

  • Polylactic acid — The skeletal formula of poly(lactic acid) Poly(lactic acid) or polylactide (PLA) is a thermoplastic aliphatic polyester derived from renewable resources, such as corn starch (in the United States), tapioca products (roots, chips or starch mostly… …   Wikipedia

  • LACTIDES — Famille d’esters qui sont formés par condensation interne et cyclisation, avec élimination d’eau, de deux molécules d’un 見 hydroxyacide ou de son anhydride. Les lactides ont pour formule générale: Le premier composé de cette série est le lactide… …   Encyclopédie Universelle

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