Van Guyse Joachim F R, Bernhard Yann, Hoogenboom Richard
Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281-S4, Ghent, B-9000, Belgium.
Macromol Rapid Commun. 2020 Oct;41(19):e2000365. doi: 10.1002/marc.202000365. Epub 2020 Aug 17.
Only recently, post-polymerization modification reactions of unactivated polyacrylates have been emerging as an attractive alternative to utilizing reactive monomers, enabling the synthetic upcycling of these widely applied polymers. Within this contribution, the triazabicyclodecene-catalyzed transesterification of polyacrylates is reported, including the reaction kinetics and the broad scope for macromolecular design of functional copolyacrylates. More specifically, the transesterification is performed under equilibrium conditions with a set of primary alcohols whereby the reaction kinetics and the obtained conversion as a function of stoichiometric excess of alcohol are evaluated. The results show that the obtained conversion is dependent on the polarity of the solvent and of the alcohol. Through this approach, the transesterification degree can be accurately controlled by stoichiometry, enabling the precise modulation of the macromolecular structure. Finally, the utility of this approach is demonstrated to incorporate functional side chains that are incompatible with radical polymerization, to facilitate Diels-Alder and thiol-ene reactions, enabling access to a broad range of functional materials from simple polyacrylate homopolymer precursors.
直到最近,未活化聚丙烯酸酯的聚合后修饰反应才作为一种有吸引力的替代方法出现,以取代使用反应性单体,从而实现这些广泛应用的聚合物的合成升级。在本论文中,报道了三氮杂双环癸烯催化的聚丙烯酸酯的酯交换反应,包括反应动力学以及功能性共聚聚丙烯酸酯的大分子设计的广泛范围。更具体地说,酯交换反应是在平衡条件下与一组伯醇进行的,据此评估反应动力学以及作为醇的化学计量过量的函数所获得的转化率。结果表明,所获得的转化率取决于溶剂和醇的极性。通过这种方法,可以通过化学计量精确控制酯交换程度,从而实现对大分子结构的精确调节。最后,证明了这种方法在引入与自由基聚合不相容的功能性侧链方面的实用性,以促进狄尔斯-阿尔德反应和硫醇-烯反应,从而能够从简单的聚丙烯酸酯均聚物前体获得多种功能性材料。