影像科学与光化学 ›› 2008, Vol. 26 ›› Issue (5): 365-376.DOI: 10.7517/j.issn.1674-0475.2008.05.365

• 研究论文 • 上一篇    下一篇

本体与界面条件下MAPTMS水解-缩合过程中簇集行为比较研究

左冬梅, 沈淑坤, 胡道道   

  1. 陕西师范大学, 化学与材料科学学院, 陕西, 西安710062
  • 收稿日期:2007-12-27 修回日期:2008-04-14 出版日期:2008-09-23 发布日期:2008-09-23
  • 基金资助:
    国家自然科学基金资助课题(20773084)

Study on the Difference in Aggregation Behavior Between Bulk Phase and Air-Water Interface for Hydrolysis-Condensation Process of MAPTMS

ZUO Dong-mei, SHEN Shu-kun, HU Dao-dao   

  1. School of Chemistry and Materials Science, Shaanxi Normal University, Xi’an 710062, Shaanxi, P. R. China
  • Received:2007-12-27 Revised:2008-04-14 Online:2008-09-23 Published:2008-09-23

摘要: 以甲基丙烯酰氧丙基三甲氧基硅烷(MAPTMS)为前驱体,利用荧光光谱、在线衰减全反射红外光谱(In-situ ATR-FT-IR),比较性地研究了在本体及气液界面条件下MAPTMS在酸性介质中的水解-缩合过程.借助于LB膜技术,测定了MAPTMS在气液界面水解-缩合反应过程中的π-A曲线.不论在本体相还是气液界面相,荧光探针芘均表现出明显的芘分子完全重叠及部分重叠的激基缔合物的荧光发射特征.结果表明:MAPTMS水解产物在水相中发生簇集,而且簇集体疏水端相互作用存在一定刚性.芘的荧光光谱随反应进行表现出显著变化,但本体相荧光光谱变化较气液界面相剧烈.ATR-FT-IR光谱在线检测表明:本体水解缩合产物具有较高的聚合度,而气液界面水解缩合产物聚合度较低.上述结果说明体系中存在簇集行为的显著变化,且在气液界面MAPTMS水解产物受限程度比本体相大.分子在气液界面上的聚集行为也由-πA曲线的结果得到进一步证实.文中依据MAPTMS水解产物具有类似表面活性剂的特性对上述实验结果给予了解释.

关键词: 甲基丙烯酰氧丙基三甲氧基硅烷, 水解-缩合, 荧光探针, π-A曲线, 簇集, 本体相和气液界面

Abstract: The aggregation behaviors occurred in bulk phase and at air-water interface for hydrolysis-condensation processe of 3-methacryloxypropyltrimethoxysilane(MAPTMS) were comparatively investigated.The fluorescence spectra of pyrene as probe introduced in the bulk phase and air-water interface implied that there were aggregations of hydrolyzates in bulk phase and at air-water interface.Additionally,the variations in fluorescence spectra with time manifested that both hydrolysis and condensation occurred in bulk phase were faster than that at air-water interface.These conclusions were coincident with the results derived from In-situ ATR-FT-IR and π-A isotherm measurement.The changes in the emission intensity of pyrene were also observed for both cases of bulk phase and air-water interface,indicating that the size of aggregates was changable.All findings related to the aggregation could be interpreted in terms of the hydrolyzed MAPTMS being similar to amphiphilic molecule,and difference in the fluorescence spectra and IR spectra for the bulk phase and air-water interface could be attributed to the difference in the degree of molecular confinement in two cases.It is the difference in the degree of molecular confinement that makes the hydrolysis and condensation of MAPTMS different in two cases.

Key words: 3-methacryloxypropyltrimethoxysilane, hydrolysis and condensation, fluorescent probe, π-A isotherm, aggregation, bulk phase, air-water interface

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