通过偏光显微镜和DSC技术,较为详细地研究了不同端基及分子量PEO的结晶行为.当PEO的分子量大于6000 g/mol时,分子量对其结晶行为的影响逐渐变得很小;当分子量介于6000 g/mol～2000 g/mol时,为一临界分子量区,分子量变化对其结晶能力有很大的影响.氯乙基酯端基PEO链的折叠结晶受限较大,结晶度损失较大.而且,当分子量降至临界分子量区时,PEO结晶受限对端基体积更加敏感,结晶能力大大降低.羟基端基对结晶熔融焓(ΔHf)的影响与分子量的大小有强烈的关系.Tm仅随着端基体积的变大而下降.
参考文献
| [1] | Hartly A;Leung Y K;Booth C .[J].POLYMER,1976,17:354. |
| [2] | Fraser M J;Marshall A;Booth C .[J].Polymer,1977,18:93. |
| [3] | Ashman P C;Booth C .[J].Polymer,1973,14:300. |
| [4] | Cooper D R;Booth C .[J].Polymer,1977,18:164. |
| [5] | Kovacs A J;Straupe C .[J].Journal of Crystal Growth,1980,48:210. |
| [6] | Cheng S Z D;Chen J J;Zhang A Q et al.[J].Journal of Polymer Science Part B:Polymer Physics,1991,29:299. |
| [7] | Cheng S Z D;Wu S S;Chen J et al.[J].Macromolecules,1993,26:5105. |
| [8] | Lee S W;Chen E Q;Zhang A et al.[J].Macromolecules,1996,29:8816. |
| [9] | Chen E Q;Lee S W;Zhang A et al.[J].Polymer,1999,40:4543. |
| [10] | Chen E Q;Lee S W;Zhang A et al.[J].Macromolecules,1999,32:4784. |
| [11] | Cheng SY.;Yuan JJ.;Ji PJ.;Xu J.;Ye ML.;Shi LH.;Xu ZS. .Synthesis and characterization of polystyrene-b-poly(ethylene oxide)-b-polystyrene triblock copolymers by atom-transfer radical polymerization[J].Journal of Applied Polymer Science,2000(13):2882-2888. |
| [12] | Mandelkern L .[J].Journal of Applied Physics,1955,26:443. |
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