کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5186362 | 1381102 | 2006 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Raman microspectroscopy study of structure, dispersibility, and crystallinity of poly(hydroxybutyrate)/poly(l-lactic acid) blends
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The structure, dispersibility, and crystallinity of poly(3-hydroxybutyrate) (PHB) and poly(l-lactic acid) (PLLA) blends are investigated by using Raman microspectroscopy. Four kinds of PHB/PLLA blends with a PLLA content of 20, 40, 60, and 80 wt% were prepared from chloroform solutions. Differences in the Raman microspectroscopic spectra between the spherulitic and nonspherulitic parts in the blends mainly lie in the CO stretching band and C-O-C and C-C skeletal stretching bands of PHB and PLLA. In addition to such bands, the Raman spectra of spherulitic structure in the blends show a band due to the CH3 asymmetric stretching mode at an unusually high frequency (3009 cmâ1), suggesting the existence of a C-Hâ¯OC hydrogen bond of PHB in the spherulite. The existence of C-Hâ¯OC hydrogen bond is one of the unambiguous evidence for the crystallization of PHB component in the blends. Therefore, it is possible to distinguish Raman bands due to each component in the spectra of blends. Raman spectra of the spherulitic structure in the blends are similar to a Raman spectrum of pure crystalline PHB, while those of the nonspherulitic parts in the blends have each component peak of PHB and PLLA. The present study reveals that the PHB component is crystallized in the blends irrespective of the blend ratio, and that both components are mixed in the nonspherulite parts. The crystalline structure of PHB and the nonspherulitic parts of PLLA in the blends are characterized, respectively, by the unique band of C-Hâ¯OC hydrogen bond at 3009 cmâ1 and CCO deformation bands near 400 cmâ1.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 47, Issue 9, 19 April 2006, Pages 3132-3140
Journal: Polymer - Volume 47, Issue 9, 19 April 2006, Pages 3132-3140
نویسندگان
Tsuyoshi Furukawa, Harumi Sato, Rumi Murakami, Jianming Zhang, Isao Noda, Shukichi Ochiai, Yukihiro Ozaki,