کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7789189 | 1500636 | 2015 | 4 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Preparation of zwitterionically charged nanocrystals by surface TEMPO-mediated oxidation and partial deacetylation of α-chitin
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Preparation of zwitterionically charged nanocrystals by surface TEMPO-mediated oxidation and partial deacetylation of α-chitin Preparation of zwitterionically charged nanocrystals by surface TEMPO-mediated oxidation and partial deacetylation of α-chitin](/preview/png/7789189.png)
چکیده انگلیسی
Zwitterionic nanocrystals were prepared by TEMPO-mediated oxidation, partial deacetylation, and subsequent mechanical disintegration of α-chitin. The pH dependence of the morphology, transparency, and viscosity of the nanocrystals were evaluated. After those reactions, the carboxylate and amino group contents of the chitin derivative were 0.45 and 1.26 mmol/g, respectively. After mechanical treatment, the water dispersion consisted of nanocrystals approximately 250 nm long and 10 nm thick. Under acidic and basic conditions, the water dispersions were highly transparent. On the other hand, under neutral conditions, the dispersion was turbid due to the ionic interaction between the cationic and anionic groups on the nanocrystal surface. Although the surface zwitterionic nanocrystals collected from acidic and basic dispersion were randomly oriented due to electrostatic repulsions, nanocrystals formed aggregates in neutral water due to the cationic and anionic interaction between them. Nanocrystals in neutral water had higher viscosity than those in acidic and basic water, since ionic interaction caused nanocrystal networks to form in water.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbohydrate Polymers - Volume 122, 20 May 2015, Pages 1-4
Journal: Carbohydrate Polymers - Volume 122, 20 May 2015, Pages 1-4
نویسندگان
Shinsuke Ifuku, Taishi Hori, Hironori Izawa, Minoru Morimoto, Hiroyuki Saimoto,