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Release of Thyme Oil from Polylactide Microcapsules / Isabel M. Martins in Industrial & engineering chemistry research, Vol. 50 N° 24 (Décembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 24 (Décembre 2011) . - pp. 13752-13761 Titre : Release of Thyme Oil from Polylactide Microcapsules Type de document : texte imprimé Auteurs : Isabel M. Martins, Auteur ; Sofia N. Rodrigues, Auteur ; Maria F. Barreiro, Auteur Année de publication : 2012 Article en page(s) : pp. 13752-13761 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Microcapsule Résumé : Microencapsulation reveals numerous advantages over conventional applications of flavors or fragances. Thus, the goal of this work was to study the release rate of thyme oil through the polylactide (PLA) microcapsules prepared by coacervation. Microcapsules have spherical shape and a mean particle size of 36 μm. The results show that the release of thymol is faster in the first hour and remains almost constant in the next days. Moreover, it was observed that the release of the polar compounds of thyme oil is faster than the apolar ones. The diffusion coefficient in the first hour of release was 1.39 × 10―15 m2/s for thymol and 5.21 × 10―17 m2/s for p-cymene. For a period of 5 drays, diffusion coefficients of 3.81 × 10―17M2/s for thymol and 1.43 x 10―18 m2/s for cymene were determined. The diffusion of thyme oil from the PLA cross-linked membrane was dependent on the microcapsules morphological characteristics. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25299838 [article] Release of Thyme Oil from Polylactide Microcapsules [texte imprimé] / Isabel M. Martins, Auteur ; Sofia N. Rodrigues, Auteur ; Maria F. Barreiro, Auteur . - 2012 . - pp. 13752-13761. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 24 (Décembre 2011) . - pp. 13752-13761 Mots-clés : Microcapsule Résumé : Microencapsulation reveals numerous advantages over conventional applications of flavors or fragances. Thus, the goal of this work was to study the release rate of thyme oil through the polylactide (PLA) microcapsules prepared by coacervation. Microcapsules have spherical shape and a mean particle size of 36 μm. The results show that the release of thymol is faster in the first hour and remains almost constant in the next days. Moreover, it was observed that the release of the polar compounds of thyme oil is faster than the apolar ones. The diffusion coefficient in the first hour of release was 1.39 × 10―15 m2/s for thymol and 5.21 × 10―17 m2/s for p-cymene. For a period of 5 drays, diffusion coefficients of 3.81 × 10―17M2/s for thymol and 1.43 x 10―18 m2/s for cymene were determined. The diffusion of thyme oil from the PLA cross-linked membrane was dependent on the microcapsules morphological characteristics. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25299838

Release studies of thymol and p - cymene from polylactide microcapsules / Isabel M. Martins in Industrial & engineering chemistry research, Vol. 51 N° 35 (Septembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 35 (Septembre 2012) . - pp. 11565-11571 Titre : Release studies of thymol and p - cymene from polylactide microcapsules Type de document : texte imprimé Auteurs : Isabel M. Martins, Auteur ; Sofia N. Rodrigues, Auteur ; Maria F. Barreiro, Auteur Année de publication : 2012 Article en page(s) : pp. 11565-11571 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Microcapsule Résumé : The objective of this work is to access the release behavior of thymol and p-cymene used as model core materials with PLA microcapsules. The microcapsules were obtained by a coacervation process developed in a previous work and present a spherical shape with mean particle size of 25 and 37 μm for thymol and p-cymene, respectively. The results have shown that the release of thymol and p-cymene is faster in the first hour keeping almost constant in the subsequent days. The diffusion coefficient in the first hour of release was 1.99 × 10―16 m2/s for thymol and 4.34 × 10―16 m2/s for p-cymene. However, the diffusion was slower if considering a period of 5 days being the diffusion coefficients of 3.34 × 10―19 m2/s for thymol and 3.45 X 10―18 m2/s for cymene. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26324807 [article] Release studies of thymol and p - cymene from polylactide microcapsules [texte imprimé] / Isabel M. Martins, Auteur ; Sofia N. Rodrigues, Auteur ; Maria F. Barreiro, Auteur . - 2012 . - pp. 11565-11571. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 35 (Septembre 2012) . - pp. 11565-11571 Mots-clés : Microcapsule Résumé : The objective of this work is to access the release behavior of thymol and p-cymene used as model core materials with PLA microcapsules. The microcapsules were obtained by a coacervation process developed in a previous work and present a spherical shape with mean particle size of 25 and 37 μm for thymol and p-cymene, respectively. The results have shown that the release of thymol and p-cymene is faster in the first hour keeping almost constant in the subsequent days. The diffusion coefficient in the first hour of release was 1.99 × 10―16 m2/s for thymol and 4.34 × 10―16 m2/s for p-cymene. However, the diffusion was slower if considering a period of 5 days being the diffusion coefficients of 3.34 × 10―19 m2/s for thymol and 3.45 X 10―18 m2/s for cymene. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26324807