A facile route to ketene-functionalized polymers for general materials applications
作者:Frank A. Leibfarth、Minhyuk Kang、Myungsoo Ham、Joohee Kim、Luis M. Campos、Nalini Gupta、Bongjin Moon、Craig J. Hawker
DOI:10.1038/nchem.538
日期:2010.3
Function matters in materials science, and methodologies that provide paths to multiple functionality in a single step are to be prized. Therefore, we introduce a robust and efficient strategy for exploiting the versatile reactivity of ketenes in polymer chemistry. New monomers for both radical and ring-opening metathesis polymerization have been developed, which take advantage of Meldrum's acid as both a synthetic building block and a thermolytic precursor to dialkyl ketenes. The ketene-functionalized polymers are directly detected by their characteristic infrared absorption and are found to be stable under ambient conditions. The inherent ability of ketenes to provide crosslinking via dimerization and to act as reactive chemical handles via addition, provides simple methodology for application in complex materials challenges. Such versatile characteristics are illustrated by covalently attaching and patterning a dye through microcontact printing. The strategy highlights the significant opportunities afforded by the traditionally neglected ketene functional group in polymer chemistry. The ability to rapidly functionalize polymers is vital for application development. Here, a method for the introduction of masked ketenes into monomers for both ring-opening metathesis and radical-type polymerizations is described. These ketenes â a group previously underexploited in polymer chemistry â allow both crosslinking and post-polymerization functionalization of the polymers.
在材料科学中,功能非常重要,而能够在一个步骤中提供多种功能性途径的方法是值得推崇的。因此,我们介绍了一种稳健高效的策略,以利用烯酮在聚合物化学中的多功能反应性。我们开发了用于自由基聚合和开环偏聚的新型单体,这些单体既利用了梅尔德伦酸作为合成构件的优势,又利用了二烷基烯酮的热解前体的优势。酮官能化聚合物可直接通过其特有的红外吸收进行检测,并在环境条件下保持稳定。烯酮固有的能力是通过二聚化提供交联,并通过加成充当活性化学处理剂,这为应用于复杂材料挑战提供了简单的方法。通过微接触印刷对染料进行共价连接和图案化,就能体现这种多功能特性。这一策略凸显了传统上被忽视的烯酮官能团在聚合物化学中带来的重要机遇。快速功能化聚合物的能力对于应用开发至关重要。本文介绍了一种在开环偏聚和自由基型聚合的单体中引入掩蔽烯酮的方法。这些烯酮是聚合物化学中以前未得到充分利用的一个基团,可以对聚合物进行交联和聚合后官能化。