title: Copolymerization of D,L-lactide and glycolide in supercritical carbon dioxide with zinc octoate as catalyst.
abstract: The objective of the study is the development of a new technique based on supercritical technology for the production of bioabsorbable polymeric microparticles containing pharmaceutical principles, for their use in the controlled release of medicines. For this purpose, the ring-opening copolymerization of D,L-lactide and glycolide in supercritical carbon dioxide, using zinc(II) 2-ethylhexanoate (ZnOct2) as catalyst, was studied. The polymer obtained with ZnOct2 has similar characteristics to that obtained with stannous octoate (SnOct2), the conventional catalyst used up to now for this kind of polymerization process. Experiments were performed at various reaction times, pressures, and stirring rates. The most outstanding result was found by varying the stirring rate, where particles forming agglomerates seem to be obtained at the greater agitation levels.
authors.affiliation: Faculty of Chemistry, Department of Chemical Engineering, University of Castilla-La Mancha, Ciudad Real, Spain.
authors.forename: Rosario
authors.initials: R
authors.lastname: Mazarro
authors.forename: Antonio
authors.initials: A
authors.lastname: de Lucas
authors.forename: Ignacio
authors.initials: I
authors.lastname: Gracia
authors.forename: Juan F
authors.initials: JF
authors.lastname: Rodríguez
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry / Q000378:metabolism; D002245:Carbon Dioxide / Q000737:chemistry*; D003692:Delayed-Action Preparations / Q000737:chemistry / Q000378:metabolism; D004337:Drug Carriers / Q000737:chemistry / Q000378:metabolism; D019344:Lactic Acid / Q000737:chemistry* / Q000378:metabolism; D008422:Materials Testing; D008863:Microspheres; D015394:Molecular Structure; D010316:Particle Size; D011100:Polyglycolic Acid / Q000737:chemistry* / Q000378:metabolism; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism; D015032:Zinc / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D011108:Polymers; D002245:Carbon Dioxide; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D015032:Zinc