Surface Functionalization of Silica with 2‐Vinylfuran by Cationic Polymerization

Abstract

Cationic surface polymerization of 2‐vinylfuran with chlorotriphenylmethane as initiator has been used for the functionalization of silica particles. The influence of monomer/initiator ratio and temperature on grafting efficiency, yield, and degree of grafting has been investigated. Grafting efficiency is a significant function of temperature and monomer/initiator ratio, because crosslinking reactions between cationically active chains increases the amount of the immobilized polyvinylfuran fraction. Thus, larger initiator concentrations on the silica cause higher polymer content on the surface. Polymer structure elucidation and surface properties are analyzed by means of solid‐state NMR spectroscopy, UV‐vis spectroscopy, BET – measurements, and scanning electron microscopy.

Cationic Polymerization of 2‐Vinylthiophene by Chloroarylmethanes as Surface Initiators on Silica and Consecutive Hydride Abstraction by Acceptors

“…[14] 1 H and 13 C NMR spectra in solution were measured at room temperature with a Varian Gemini 300 MHz spectrometer at 300 MHz ( 1 H NMR) and 75 MHz ( 13 C NMR) or a Bruker Avance 250 MHz spectrometer at 250 MHz ( 1 H NMR) and 62.9 MHz ( 13 C NMR). CDCl 3 served as solvent and residual protons from CHCl 3 and natural abundant 13 C from 13 CDCl 3 were used as internal references.…”

“…Similar NMR results were found for cationically produced polycyclopentadiene/silica [21] and poly(vinyl furan)/silica composites. [14] The signals at about d ¼ 123 ppm and 148 ppm can be assigned to carbon atoms of the thiophene ring according to the 13 C NMR spectrum of the soluble PVT. [13] The signals at d ¼ 113 ppm and at d ¼ …”

“…Similar results have been obtained for the cationic polymerization of 2-vinylfuran on silica. [14] Unfortunately, PVT without structural defects is not available by cationic polymerization, because the thiophene ring also undergoes electrophilic substitution reactions via the five position of the ring during the desired chain propagation reaction of the vinyl double bond. Thus, a low amount of branching points and tertiary C-atoms is present in the polymer chain.…”

Copper‐mediated radical polymerization on a microcellular monolith surface

“…Indeed, a low loading for scavenging chemistry means that a substantial quantity of the material is required, and this leads to a higher cost. Recently, a strategy already used in surface modification,3–11 which consists of polymerization from a solid support, has provided access to high‐loading resins. Various ways are reported in the literature to achieve it: ring‐opening metathesis polymerization onto vinyl polystyrene,12 dendrimer growth from modified polystyrene supports,13 radical polymerization of styrenic derivatives on polymer disks,14 nitroxide‐mediated polymerization from 2,2,6,6‐tetramethylpiperidinyl‐1‐oxy (TEMPO)‐methyl resin,15 and the use of atom transfer radical polymerization (ATRP) to attach poly(methacrylate)s to Wang resins 16.…”

Polymer Brushes by Anionic and Cationic Surface-Initiated Polymerization (SIP)

“…The influence of monomer/initiator ratio and temperature on grafting efficiency, yield, and degree of grafting was investigated. Grafting efficiency was found to be a function of temperature and monomer/initator ratio, i.e., because crosslinking reactions between cationically active chains increase the amount of the immobilized polyvinylfuran fraction [103]. The cationic polymerization of electron-rich monomers such as vinyl ethers, vinyl furan, and cyclopentadiene on silica surfaces can be initiated by aryl methyl halides.…”