Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Effect of manufacturing conditions and polymer ratio on the permeability and film morphology of ethyl cellulose and hydroxypropyl cellulose free-films produced by using a novel spray method.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
2009 (English)Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

This thesis considers the effect of manufacturing conditions and polymer ratio on water permeability and morphology of free-films. A novel spray method for producing ethyl cellulose (EC) and hydroxypropyl cellulose (HPC) free-films was developed where several process parameters was controlled. The process was optimised by pre-spraying solvent until the system reached a steady-state temperature. This minimised the variation of outlet air temperature to < 2.5 °C. Coating time was approximately 4 minutes excluding drying.

Free-films were produced using 94 wt% solvent (95 %-ethanol) and 6 wt% polymer. The amount of HPC in the films was varied (wt% HPC defined as HPC/(HPC+EC)*100). Films with 30-40-50-57 wt% HPC were studied. Phase diagrams was constructed to study the phase transformation of polymer mixtures. Results show that all polymer mixtures with HPC content above 30 wt% were phase separated prior to film manufacturing. Temperature had an effect on the polymer phase transformation. In the phase diagram, the 2-phase area was larger for temperatures above 40 °C.

The investigated manufacturing conditions were outlet air temperature (°C) and spray rate (g/min). Outlet air temperature was controlled by adjusting the inlet air temperature. The films were characterized by measuring water permeability (m2/s). Cross section structure of the films was analyzed with confocal laser scanning microscopy (CLSM). FITC-HPC was added for enhanced contrast between the domains.

Higher outlet air temperature gave higher water permeability of the film whereas higher spray rate gave lower water permeability. The outlet air temperature had an impact on evaporation rate. The evaporation rate together with spray rate affected the solidification and hence the structure of the film. Images show that longer solidification time smeared the domains into larger domains. Lower water permeability was caused by less connectivity between the pores.

In conclusion, experiments show that water permeability of EC/HPC free-films was highly dependent on the manufacturing conditions.

 

Place, publisher, year, edition, pages
2009. , p. 40
Series
UPTEC K, ISSN 1650-8297 ; 09 024
Keywords [en]
free-film, confocal laser scanning microscopy, water permeability
Identifiers
URN: urn:nbn:se:uu:diva-121842OAI: oai:DiVA.org:uu-121842DiVA, id: diva2:306736
Presentation
2009-09-18, C8:321, Uppsala Biomedicinska Centrum BMC, Husarg. 3, Uppsala, 13:15 (English)
Uppsok
Technology
Supervisors
Examiners
Available from: 2010-04-23 Created: 2010-03-30 Last updated: 2010-04-23Bibliographically approved

Open Access in DiVA

fulltext(1344 kB)1574 downloads
File information
File name FULLTEXT01.pdfFile size 1344 kBChecksum SHA-512
c798da5081713dad6ceebf3c10400c87a6ecb2ab070b9c5d8392d5bf79a267991c27b81b614187cf6f9afc43f85750ecb0d4b88398938f1dd45820df8bd983f2
Type fulltextMimetype application/pdf

By organisation
Department of Pharmacy

Search outside of DiVA

GoogleGoogle Scholar
Total: 1574 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 673 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf