کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1384813 1500608 2016 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
NMR study on the network structure of a mixed gel of kappa and iota carrageenans
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
NMR study on the network structure of a mixed gel of kappa and iota carrageenans
چکیده انگلیسی


• NMR measurements clarify the process of network formation in mixed CR gel.
• Longer chains preferentially form aggregates, reducing average Mw of solute CRs.
• Diffusion of a probe indicates IPN or phase separation in mixed CR gels.

The temperature dependencies of the 1H T2 and diffusion coefficient (D) of a mixed solution of kappa-carrageenan and iota-carrageenan were measured by NMR. Rheological and NMR measurements suggested an exponential formation of rigid aggregates of kappa-carrageenan and a gradual formation of fine aggregates of iota-carrageenan during two step increases of G′. The results also suggested that longer carrageenan chains are preferentially involved in aggregation, thus resulting in a decrease in the average Mw of solute carrageenans. The results of diffusion measurements for poly(ethylene oxide) (PEO) suggested that kappa-carrageenan formed thick aggregates that decreased hindrance to PEO diffusion by decreasing the solute kappa-carrageenan concentration in the voids of the aggregated chains, and that iota-carrageenan formed fine aggregates that decreased the solute iota-carrageenan concentration less. DPEO in a mixed solution of kappa-carrageenan and iota-carrageenan suggested two possibilities for the microscopic network structure: an interpenetrating network structure, or micro-phase separation.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbohydrate Polymers - Volume 150, 5 October 2016, Pages 57–64
نویسندگان
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