Glass-transition behaviour of plasticized starch biopolymer system - A modified Gordon-Taylor approach
Two plasticizers namely, glycerol and xylitol, based on their similar molecular size (6.3 A) but different molecular weights (Glycerol-92; Xylitol-152) were selected for studying the glass-transition behaviour (rubber like behaviour) in multi-plasticized starch biopolymer with about 70% amylopectin...
| Main Authors: | , , |
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| Format: | Journal Article |
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Elsevier BV
2011
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| Online Access: | http://hdl.handle.net/20.500.11937/32369 |
| _version_ | 1848753644572246016 |
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| author | Chaudhary, Deeptangshu Adhikari, B. Kasapis, S. |
| author_facet | Chaudhary, Deeptangshu Adhikari, B. Kasapis, S. |
| author_sort | Chaudhary, Deeptangshu |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Two plasticizers namely, glycerol and xylitol, based on their similar molecular size (6.3 A) but different molecular weights (Glycerol-92; Xylitol-152) were selected for studying the glass-transition behaviour (rubber like behaviour) in multi-plasticized starch biopolymer with about 70% amylopectin structure. In the calorimetry measurements, glass-transition temperatures (onset temperature for bulk viscous flow) of plasticized samples were higher than non-plasticized samples at low water activities, thus showing typical antiplasticization behaviour. However, when plasticizer concentration was increased up to 15% and 20% wt, all plasticized samples showed significant reduction in glass-transition temperature. We used a modified Gordon-Taylor model to understand the competitive plasticization of glycerol and xylitol in presence of water, and suggest that competitive plasticization exists and occurs at a threshold amount of matrix free water content, due to strong three-way interactions: starch-plasticizer, plasticizer-plasticizer/water and starch-water. This competitive interaction is significant in determining the onset temperature for viscous flow behaviour; at higher matrix water content, the Gordon-Taylor constant was relatively unaffected by the plasticizer amount, and water was the dominant plasticizer. A new interaction parameter that separates the starch-plasticizer interaction in a starch-plasticizer-water system is also discussed. |
| first_indexed | 2025-11-14T08:27:48Z |
| format | Journal Article |
| id | curtin-20.500.11937-32369 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:27:48Z |
| publishDate | 2011 |
| publisher | Elsevier BV |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-323692017-09-13T16:07:34Z Glass-transition behaviour of plasticized starch biopolymer system - A modified Gordon-Taylor approach Chaudhary, Deeptangshu Adhikari, B. Kasapis, S. Two plasticizers namely, glycerol and xylitol, based on their similar molecular size (6.3 A) but different molecular weights (Glycerol-92; Xylitol-152) were selected for studying the glass-transition behaviour (rubber like behaviour) in multi-plasticized starch biopolymer with about 70% amylopectin structure. In the calorimetry measurements, glass-transition temperatures (onset temperature for bulk viscous flow) of plasticized samples were higher than non-plasticized samples at low water activities, thus showing typical antiplasticization behaviour. However, when plasticizer concentration was increased up to 15% and 20% wt, all plasticized samples showed significant reduction in glass-transition temperature. We used a modified Gordon-Taylor model to understand the competitive plasticization of glycerol and xylitol in presence of water, and suggest that competitive plasticization exists and occurs at a threshold amount of matrix free water content, due to strong three-way interactions: starch-plasticizer, plasticizer-plasticizer/water and starch-water. This competitive interaction is significant in determining the onset temperature for viscous flow behaviour; at higher matrix water content, the Gordon-Taylor constant was relatively unaffected by the plasticizer amount, and water was the dominant plasticizer. A new interaction parameter that separates the starch-plasticizer interaction in a starch-plasticizer-water system is also discussed. 2011 Journal Article http://hdl.handle.net/20.500.11937/32369 10.1016/j.foodhyd.2010.06.002 Elsevier BV restricted |
| spellingShingle | Chaudhary, Deeptangshu Adhikari, B. Kasapis, S. Glass-transition behaviour of plasticized starch biopolymer system - A modified Gordon-Taylor approach |
| title | Glass-transition behaviour of plasticized starch biopolymer system - A modified Gordon-Taylor approach |
| title_full | Glass-transition behaviour of plasticized starch biopolymer system - A modified Gordon-Taylor approach |
| title_fullStr | Glass-transition behaviour of plasticized starch biopolymer system - A modified Gordon-Taylor approach |
| title_full_unstemmed | Glass-transition behaviour of plasticized starch biopolymer system - A modified Gordon-Taylor approach |
| title_short | Glass-transition behaviour of plasticized starch biopolymer system - A modified Gordon-Taylor approach |
| title_sort | glass-transition behaviour of plasticized starch biopolymer system - a modified gordon-taylor approach |
| url | http://hdl.handle.net/20.500.11937/32369 |