Controllable one-pot polycondensation of block polyaramid by temporary suppression of nucleophilicity. (19th April 2022)

• Record Type: Journal Article
• Authors: Li, Yongjiu; Dai, Yu; Gao, Yue; Zhang, Dajie; Lv, Junwei; Yin, Qian; Liu, Xiangyang; Luo, Longbo
• Is Part Of: Polymer. Volume 246(2022)
• Publication Date: 2022-04-19
• Subjects: Block polymer -- Coordination -- Polyaramid; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2022.124758
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: Herein, we introduce controllable one-pot polycondensation which can prepare block aromatic polyamide by regulating nucleophilicity of amino groups through reversible coordination interaction. Due to different coordination ability of diamine monomers with Cu 2+, effect of Cu 2+ on its nucleophilicity is quite different and nucleophilicity is suppressed more significantly for the diamines with stronger coordination ability. Then, reactivity difference of diamine monomers owning different coordination ability can be magnified significantly through coordination interaction. When the two kinds of diamine monomers with different coordination ability exist in the reaction system, diamine monomer with weaker coordination ability reacts quickly with diacyl chloride in the initial phase of the reaction and forms corresponding chain segments. When the diamine monomer with weaker coordination ability is nearly depleted, the diamine monomer with stronger coordination ability begins to undergo uncoordinated reaction with Cu 2+, restoring its reactivity with acyl chloride and forming corresponding chain segment in the second stage reaction. Graphical abstract: Image 1 Highlights: Coordination interaction between Cu 2+ and diamines with different chemical structure was characterized. The nucleophilicity of diamine monomer with strong coordination ability is suppressed significantly. Block polyaramid is prepared through controllable one-pot polycondensation by utilizing coordination ability difference. The polyaramid synthesized with addition of Cu 2+ has narrower molecular weight distribution.