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一个ab initio乳液原子转移基聚合物的开发:从微乳液到乳液
Ke Min1, Haifeng Gao, Krzysztof Matyjaszewski
1Center for Macromolecular Engineering, Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA.
Journal of the American Chemical Society
|August 10, 2006
概括
一种新的两步方法使得可控的ab initio乳液聚合利用由电子转移 (AGET) ATRP产生的激活剂. 这种技术减少了表面活性剂的使用,并产生了具有狭窄分子量分布的聚合物.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 原子转移基聚合 (ATRP) 是一种多用途的受控聚合技术.
- 乳液聚合为大规模合成提供了优势,但使用ATRP控制它可能具有挑战性.
研究的目的:
- 使用两步程序开发一个受控的初始乳液ATRP系统.
- 优化表面活性剂和催化剂度,以实现高效的乳液聚合.
- 为了在最终的聚合物乳中实现高单体转化和狭窄的分子量分布.
主要方法:
- 使用了两步程序:初始微乳液ATRP,然后添加单体.
- 采用电子转移 (AGET) 启动技术与Cu (II) /甲酸生成的激活剂.
- 调整了催化剂度和单体比,以减少表面活性剂度.
主要成果:
- 实现了控制的乳液聚合,具有线性第一阶动力学和狭窄的分子量分布 (Mw/Mn = 1.2-1.4).
- 在5-6小时内达到70-90%的单体转化.
- 生产的稳定乳颗粒大小~120nm和高链末功能,使得在现场区块共聚合物合成.
结论:
- 两个步骤的ab initio乳液ATRP方法为受控聚合提供了一个强大的平台.
- 这种方法最大限度地降低了表面活性剂的要求,并促进了功能聚合物和块共聚合物的合成.
- 对于受控乳液ATRP,AGET启动是有效的,避免了催化剂运输问题.
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