Dissertation/ Thesis
Synthesis, Characterization and Physical Properties of Amphiphilic Rod-Coil DEH-PPV-b-PNIPAM Block Copolymers
| العنوان: | Synthesis, Characterization and Physical Properties of Amphiphilic Rod-Coil DEH-PPV-b-PNIPAM Block Copolymers |
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| Alternate Title: | 雙性團聯共聚高分子DEH-PPV-b-PNIPAM之合成、物理性質鑑定玉型態學研究 |
| المؤلفون: | Hsin-Chieh Tsai, 蔡欣潔 |
| Thesis Advisors: | 林唯芳 |
| سنة النشر: | 2013 |
| المجموعة: | National Digital Library of Theses and Dissertations in Taiwan |
| الوصف: | 101 A series of poly(diethylhexyloxy-p-phenylenevinylene)-b-poly(N-isopropylacylamide) (DEH-PPV-b-PNIPAM) amphiphilic block copolymers were synthesized using Siegrist polycondensation and atom transfer radical polymerization (ATRP) followed by “click” chemistry. Theses copolymers are well-defined with PNIPAM block volume fraction from 0.40-0.72 and low polydispersity (< 1.2), as determined by 1H NMR and GPC. Due to the amphiphilic property of PNIPAM, these copolymers can be easily dissolved in polar solvent. The copolymers with all volume fractions of fPNIPAM are completely soluble in methanl and in water with fPNIPAM > 0.55. In both solutions, the copolymers show slightly blue shift of absorption (UV-Vis) and strong quenching of emission (PL), indicating H-aggregations occurred. These copolymers in polar solution were self-organized into lamellar structures with same width (6-8 nm) regardless the fPNIPAM according to the TEM studies. The average aspect ratio of these lamellae is increased from 6.5 to 13.8 when the fPNIPAM is decreasing from 0.72 to 0.48. These results suggest that the nanostructure of these copolymers is mainly dominated by the PPV block. The lower critical solution temperature (LCST) of block copolymers is increased with increasing hydrophobic DEH-PPV block ratio, since χ value between DEH-PPV and PNIPAM segment is weak to reduce the real thermo-responsive length of PNIPAM. The variation of the micelle size with temperature was judged to be similar from both TEM and DLS measurement. In bulk state, nanostructure and phase transition of the DEH-PPV-b-PNIPAM amphiphilic rod-coil block copolymers were experimentally investigated via SAXS, TEM, POM, and DSC to map the phase diagram. At low coil fraction (fPNIPAM |
| Original Identifier: | 101NTU05310007 |
| نوع الوثيقة: | 學位論文 ; thesis |
| وصف الملف: | 80 |
| الاتاحة: | http://ndltd.ncl.edu.tw/handle/52102796872976217358 |
| رقم الانضمام: | edsndl.TW.101NTU05310007 |
| قاعدة البيانات: | Networked Digital Library of Theses & Dissertations |
| الوصف غير متاح. |