Documents disponibles écrits par cet auteur

Microencapsulation of limonene for textile application / Sofia N. Rodrigues in Industrial & engineering chemistry research, Vol. 47 n°12 (Juin 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°12 (Juin 2008) . - p. 4142–4147 Titre : Microencapsulation of limonene for textile application Type de document : texte imprimé Auteurs : Sofia N. Rodrigues, Auteur ; Isabel Fernandes, Auteur ; Isabel M. Martins, Auteur ; Vera G. Mata, Auteur Année de publication : 2008 Article en page(s) : p. 4142–4147 Note générale : Bibliogr. p. 4246-4247 Langues : Anglais (eng) Mots-clés : Polyurethane−urea  microcapsules  --  textile  applications;  Limonene;  Polymerization; Résumé : Polyurethane−urea microcapsules with limonene oil as the active agent were produced by interfacial polymerization, and their suitability for textile applications was studied. Experimental conditions for the textile substrates impregnation were based on industrial requirements and set up at laboratory scale using a mini-foulard. The success of the polymerization reaction leading to the formation of the polyurethane−urea shell was checked by Fourier transform infrared spectroscopy. Particle size distributions and morphology of the microcapsules were studied using a particle size analyzer (Coulter LS230), optical microscopy, and scanning electron microscopy. The effectiveness of the textiles impregnation and the durability of the impregnation effect were evaluated by scanning electron microscopy and by headspace/GC/FID. Under the present research, a product was developed and its performance, in regard to industrial requirements, was successfully tested. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800090c [article] Microencapsulation of limonene for textile application [texte imprimé] / Sofia N. Rodrigues, Auteur ; Isabel Fernandes, Auteur ; Isabel M. Martins, Auteur ; Vera G. Mata, Auteur . - 2008 . - p. 4142–4147. Bibliogr. p. 4246-4247 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°12 (Juin 2008) . - p. 4142–4147 Mots-clés : Polyurethane−urea  microcapsules  --  textile  applications;  Limonene;  Polymerization; Résumé : Polyurethane−urea microcapsules with limonene oil as the active agent were produced by interfacial polymerization, and their suitability for textile applications was studied. Experimental conditions for the textile substrates impregnation were based on industrial requirements and set up at laboratory scale using a mini-foulard. The success of the polymerization reaction leading to the formation of the polyurethane−urea shell was checked by Fourier transform infrared spectroscopy. Particle size distributions and morphology of the microcapsules were studied using a particle size analyzer (Coulter LS230), optical microscopy, and scanning electron microscopy. The effectiveness of the textiles impregnation and the durability of the impregnation effect were evaluated by scanning electron microscopy and by headspace/GC/FID. Under the present research, a product was developed and its performance, in regard to industrial requirements, was successfully tested. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800090c

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