物理化学学报 >> 1995, Vol. 11 >> Issue (06): 541-546.doi: 10.3866/PKU.WHXB19950613

研究论文 上一篇    下一篇

嵌段共聚物溶液胶束温度行为的郑电子湮没研究

熊兴民,杨巨华,叶美玲,张迎玖,施良和   

  1. 中国科学院高能物理研究所|北京 100080|中国科学院化学研究所|北京 100080
  • 收稿日期:1994-08-17 修回日期:1995-01-26 发布日期:1995-06-15
  • 通讯作者: 熊兴民

Study of Temperature Effect of Micellar Solutions of PSDMS Block Copolymer in n-Heptane by Positron Annihilation

Xiong Xing-Min,Yang Ju-Hua,Ye Mei-Ling,Zhang Ying-Jiu,Shi Liang-He   

  1. Institute of High Energy Physics,Academic Sinica,Beijing 100080|Institute of Chemistry,Academic Sinica,Beijing 100080
  • Received:1994-08-17 Revised:1995-01-26 Published:1995-06-15
  • Contact: Xiong Xing-Min

摘要:

用正电子寿命技术研究了聚苯乙烯—二甲基硅氧烷/正庚烷二嵌段共聚物溶液胶束的温度行为.结果表明正电子湮没参数对溶液中出现的结构和微观环境的变化十分灵敏.在一定的温度范围o-Ps寿命和强度的陡然变化反映了溶液中共聚物分子聚集态随温度经历不同阶段的变化,超过临界胶束温度o-Ps寿命随温度增高而迅速地增大,这一行为反映了分子聚集体解离成自由共聚物分子的过程.

关键词: 正电子淹没, 嵌段共聚物, 胶束溶液, 温度效应

Abstract:

The positron lifetime technique has been used to study the temperature behavior of micelle in solution of polystyrene-polydimethylsiloxane diblock copolymer in n-heptane. The results indicate that positron annihilation parameters are found to be sensitive to structural and microphase changes taking place in the micellar solutions. The abrupt changes in the o-Ps lifetime and intensity observed at certain temperature appear to be associated with variations in the aggregation state of the copolymer molecules in solutions. Above the critical micelle temperature the o-Ps lifetime increases sharply with increasing temperature. This behavior indicates the process of disintegration of molecular aggregates to free copolymer molecules.

Key words: Positron annihilation;Blok copolymer;Micellar solution;Temperature effect