Exploratory Study of Ionic Polymerization Initiated by Free Ions from Laser Desorption (SGER)

激光解吸自由离子 (SGER) 引发离子聚合的探索性研究

• 批准号: 9207433
• 负责人: Mohamed Samy El-Shall
• 金额: $ 5万
• 依托单位: Virginia Commonwealth University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-05-15 至 1993-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9207433&HistoricalAwards=false
• 关键词: Exploratory; Study; Ionic; Polymerization; Initiated

This is a Small Grant for Exploratory Research (SGER). A novel technique involving the initiation of cationic polymerization using metal ions is being explored. In the experiment, Al+ or Cu+ ions are generated in the gas phase by pulsed laser vaporization/ionization of a metal target using the second harmonic of a Nd:YAG laser (532 nm). The ions are pulled toward a monomer liquid (isobutylene which can only be polymerized by cationic mechanisms) by applying appropriate electric fields across the reaction chamber. Under different experimental conditions (temperature, pressure of a carrier gas, laser energy, electric field strength, reaction time) different polymeric products (viscous liquids or solids) were obtained with average molecular weights ranging from 285 to greater than 40,000. Full characterization of these materials is currently in progress. Experiments are in progress to extend the scope of this discovery to include transition-metal ions, mixed metal ions, copolymerization, etc. This technique could lead to a powerful approach for the synthesis of a wide variety of polymeric materials with unique properties such as stability, strength, and photo/electrical conductivity.

这是探索性研究（SGER）的小额赠款。目前正在探索一种利用金属离子引发阳离子聚合的新技术。在实验中，利用Nd:YAG激光（532 nm）的二次谐波脉冲激光汽化/电离金属靶，在气相中产生Al+或Cu+离子。通过在反应室内施加适当的电场，离子被拉向单体液体（只能通过阳离子机制聚合的异丁烯）。在不同的实验条件下（温度、载气压力、激光能量、电场强度、反应时间），可以得到不同的聚合物产物（粘性液体或固体），平均分子量在285到大于40000之间。目前正在对这些材料进行全面表征。实验正在进行中，以扩大这一发现的范围，包括过渡金属离子、混合金属离子、共聚等。这项技术可能会为合成各种具有独特性能（如稳定性、强度和光电导电性）的聚合物材料提供一种强有力的方法。