Montmorillonite clay for starch-based barrier dispersion coating: Part 1 The influence of citric acid on viscosity and barrier properties
2014 (English)In: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053, 160-166 p.Article in journal (Refereed) Published
Starch-based coating formulations were draw-down coated on a paper substrate and the effect on the water vapor transmission rate, WVTR, upon montmorillonite addition was compared to that of the pure the starch matrix without added plasticizer and for poly(ethylene glycol), PEG, and citric acid, CA, as potential plasticizers. Both potential plasticizers were added at a ratio of 3 to 10 to starch. Addition of CA to the starch solution substantially lowered the WVTR of the coated papers compared to coating with a pure starch or PEG-plasticized coating. The WVTR of the papers coated with starch and CA was lower than that obtained for paper coated with non-plasticized montmorillonite-starch dispersions, and approximately similar to paper coated with montmorillonite-starch dispersions plasticized with PEG or with citric acid. Addition of montmorillointe was effective in reducing the WVTR in the case of PEG-plasticized starch but not in the case of CA. These differences in WVTR were indicated to be due to differences in the viscosity and the clay swelling indicating that CA and PEG affected the state of dispersion differently. CA was also investigated as a dispersing agent by addition in small quantities to the montmorillonite dispersion at different pH values. When this clay dispersion was added to a suspension already containing PEG, CA gave slightly reduced plastic viscosity and there was also a weak correlation between low plastic viscosity and WVTR.
Place, publisher, year, edition, pages
Elsevier, 2014. 160-166 p.
Starch; Montmorillonite; Citric acid; Poly(ethylene glycol); Rheology; Barrier properties
Research subject Chemical Engineering
IdentifiersURN: urn:nbn:se:kau:diva-27110DOI: 10.1016/j.clay.2014.04.040ISI: 000340302200022OAI: oai:DiVA.org:kau-27110DiVA: diva2:618484
ProjectsRenewable Functional Barriers