开发高性能和环境友好的含氟聚合物是非常需要的。在这项工作中,我们发现,2-重氮-1,1,1-三氟乙烷可以通过空气稳定的炔-钯(II)催化剂聚合按照活性聚合机理,提供含氟聚合物,聚(三氟甲基亚甲基),具有受控的摩尔质量和低分散性。这种聚合物在每个主链原子上都带有三氟甲基,因此具有良好的耐化学腐蚀性。高疏水性,和优良的介电常数与低介电损耗。由于三氟甲基垂饰之间的空间位阻,合成的聚(三氟甲基亚甲基)可以扭曲成稳定的螺旋。使用手性Pd(II)催化剂合成的单手优选螺旋具有高的光学活性和圆偏振发光。值得注意的是,这种聚合物在高温(>280℃)下可完全降解为(E)-1,1,1,4,4,4-六氟丁-2-烯。此外,利用生活链端,聚合物可以进一步改性。
Developing high performance and environment-friendly fluoropolymers is greatly desired. In this work, we found that 2-diazo-1,1,1-trifluoroethane can be polymerized by air-stable alkyne-palladium(II) catalysts following a living polymerization mechanism, affording a fluoropolymer, poly(trifluoromethyl methylene) in high yield with controlled molar mass and low dispersity. This polymer bears trifluoromethyl on every main chain atom and thus has good resistance to chemical corrosion, high hydrophobicity, and excellent dielectric constant with low dielectric loss. Due to the steric hindrance between the trifluoromethyl pendants, the synthetic poly(trifluoromethyl methylene) can twist into a stable helix. The one-handed preferred helices synthesized using chiral PdII -catalysts exhibit high optical activity and circularly polarized luminescence. Remarkably, such polymer can be completely degraded to (E)-1,1,1,4,4,4-hexafluorobut-2-ene at high temperatures (>280 °C). Additionally, taking advantage of the living chain end, the polymer can be further modified.