Well-Defined (Co)polymers with 5-Vinyltetrazole Units via Combination of Atom Transfer Radical (Co)polymerization of Acrylonitrile and “Click Chemistry”-Type Postpolymerization Modification

Abstract

Well-defined homo- and copolymers of acrylonitrile were prepared by atom transfer radical polymerization, which were further modified using a “click chemistry” reaction with sodium azide and zinc chloride to yield polymeric materials with 5-vinyltetrazole units. Using optimized reaction conditions ([NaN3]:[ZnCl2]:[RCN] = 4:1:1 in DMF at 120 °C for 48−50 h), essentially complete transformation of the nitrile groups was achieved, as judged from IR and 13C NMR spectra. The produced tetrazole-containing polymers had markedly better solubility or swellability in protic solvents (methanol or aqueous base solutions) compared to the precursors. Random copolymers of acrylonitrile and styrene were also grown from polystyrene and silica particles with immobilized initiator groups and were similarly modified to the corresponding tetrazole-containing polymers. All materials were characterized by means of thermogravimetry, which showed that the polymeric tetrazoles started to decompose with evolution of significant amounts of gas at 120−190 °C, i.e., at lower (by 60−130 °C) temperature than the starting nitrile-based materials.

Synthesis of Tetrazole-containing Energetic Copolymers

“…이러한 화합물들은 고에너지, 고질소 함유 물질 로 1,2,4-트리아졸의 생성열은 109 KJ/mol, 1H-1,2,3-트 리아졸은 272 KJ/mol, 테트라졸은 237.2 KJ/mol이다 [2] . 트리아졸 및 테트라졸을 포함한 고분자는 에너지 물질로 잘 알려져 있다 [3] . 우리는 에너지 물질을 연구 하는 과정에서 GAP(Glycidyl Azido Polymer)을 대신하 는 새로운 타입의 고분자로 GAP과 다양한 알킨 화합 물간의 클릭반응을 통해 얻어진 트리아졸기를 포함한 에너지 함유 고분자에 관한 보고를 하였다 [4] .…”

Polymer nanosieve membranes for CO2-capture applications

“…Recently, 'click chemistry' has been explored as a simple way for the functionalization of macromolecules [24][25][26] . Similar to the ZnCl 2 -catalyzed 'click reaction' between azide and nitrile groups to yield low molecular weight triazole compounds 24 , post-polymerization modification reactions for attaching tetrazole onto nitrile-containing aliphatic polymers (acrylonitrile-type) have in a sense been a rediscovery 24,27 . Up to now, relatively little work on the post-polymerization [2 + 3] cycloaddition modification of nitrile-containing polymers has been reported, and much of this has been on aliphatic systems such as polyacrylonitrile and its copolymers.…”

Synthesis of Fluorescent Poly(coumarin-triazoles) via a CuAAC 'click' reaction

“…The reason for this poor solubility was attributed to p-p stacking of the coumarin system, the rigid backbone structure of the polymer and the dipolar nature of the resulting 1,2,3-triazole units, 15 which frequently affects the solubility of the triazole-containing material. 16,17 In order to address the solubility problem of polytriazole 4, an RESEARCH ARTICLE J.M.V. Ngororabanga, J. Okerio and N. Mama, 90 S. Afr.…”