Cationic Polymerization of (3‐Aminopropyl)‐tris‐furfuryloxysilane Derivatives—a New Strategy for Complex Hybrid Material Synthesis

Abstract

AbstractThe trifunctional (3‐aminopropyl)‐tris‐furfuryloxysilane monomer (1) is able to undergo both twin polymerization and reaction with electrophilic compounds such as isocyanates. 1 can be readily synthesized from 3‐aminopropyptrimethoxysilane (APTMS) and furfuryl alcohol (FA). The reaction of 1 with three different aromatic isocyanates, namely phenyl isocyanate, diphenylmethane‐4,4′‐diisocyanate (MDI), and a prepolymer consisting of MDI end‐capped polytetramethylene ether glycole (PTMEG), to the corresponding substituted urea derivatives is presented. Three urea derivatives 1‐phenyl‐3‐(3‐tris‐furfuryloxysilyl)propylurea (2), diphenylmethan‐4,4′‐bis[3(tris‐furfuryloxysilyl)propyl]urea (3), bis[3(tris‐furfuryloxysilyl)‐propyl]urea‐capped PTMEG‐MDI‐prepolymer (4) as well as 1 were polymerized to multicomponent organic/inorganic hybrid materials in a one step procedure using methane sulfonic acid as catalyst. The simultaneous formations of poly furfuryl alcohol and polysiloxane networks within the hybrid material are proven by means of solid‐state NMR spectroscopic measurements. The homogeneous distribution of silicon within the solidified hybrid materials is analyzed by scanning electron microscopy, energy dispersive X‐ray spectroscopy, and high‐angle annular dark field‐scanning transmission electron microscopy (HAADF)‐STEM. Homogeneous nanostructured hybrid materials with silicon cluster sizes in the range of 2 nm have been obtained by polymerization of the urea derivatives 2, 3, and 4.