https://scholars.lib.ntu.edu.tw/handle/123456789/74957
標題: | The effect of end groups of PEG on the crystallization behaviors of binary crystalline polymer blends PEG/PLLA | 作者: | Lai, Wei-Chi Liau, Wen-Bin Lin, Tai-Tso |
關鍵字: | Blends; Crystallization; Miscibility | 公開日期: | 2004 | 卷: | 45 | 期: | 9 | 起(迄)頁: | 3073-3080 | 來源出版物: | Polymer | 摘要: | The effect of end groups (2OH, 1OH, 1CH3 and 2CH3) of poly(ethylene glycol) (PEG) on the miscibility and crystallization behaviors of binary crystalline blends of PEG/poly(L-lactic acid) (PLLA) were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). A single glass-transition temperature was observed in the DSC scanning trace of the blend with a weight ratio of 10/90. Besides, the equilibrium melting point of PLLA decreased with the increasing PEG. A negative Flory interaction parameter, χ12, indicated that the PEG/PLLA blends were thermodynamically miscible. The spherulitic growth rate and isothermal crystallization rate of PEG or PLLA were influenced when the other component was added. This could cause by the change of glass transition temperature, Tg and equilibrium melting point, T0 m. The end groups of PEG influenced the miscibility and crystallization behaviors of PEG/PLLA blends. PLLA blended with PEG whose two end groups were CH3 exhibited the greatest melting point depression, the most negative Flory interaction parameter, the least fold surface free energy, the lowest isothermal crystallization rate and spherulitic growth rate, which meant better miscibility. On the other hand, PLLA blended with PEG whose two end groups were OH exhibited the least melting point depression, the least negative Flory interaction parameter, the greatest fold surface free energy, the greatest isothermal crystallization rate and spherulitic growth rate. © 2004 Elsevier Ltd. All rights reserved. |
URI: | http://ntur.lib.ntu.edu.tw//handle/246246/95565 https://www.scopus.com/inward/record.uri?eid=2-s2.0-1842525946&doi=10.1016%2fj.polymer.2004.03.003&partnerID=40&md5=229def12209c8726f644c736060e14a6 |
ISSN: | 00323861 | SDG/關鍵字: | Crystalline materials; Crystallization; Differential scanning calorimetry; Free energy; Melting; Polyethylene glycols; Solubility; Thermodynamics; Crystallization rate; Surface free energy; Polymer blends; macrogol; polylactic acid; polymer; article; chemical analysis; crystal structure; crystallization; differential scanning calorimetry; glass transition temperature; isotherm; melting point; microscopy; miscibility; physical chemistry; thermodynamics; polymer science |
顯示於: | 材料科學與工程學系 |
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