Solvent Swelling-Induced Halogenation of Butyl Rubber Using Polychlorinated N-Alkanes: Structure and Properties

Abstract

Traditional butyl rubber halogenation technology involves the halogenation of IIR using molecular chlorine or bromine in a solution. However, this method is technologically complex. This study investigated a novel method for the halogenation of butyl rubber to enhance its stability and resistance to thermal oxidation and aggressive media. The butyl rubber was modified through mechanochemical modification, induced by solvent swelling in a polychlorinated n-alkane solution. During the modification, samples were obtained with chlorine content ranging from 3 to 15%. After extraction, the halogen content was quantitatively determined with the oxygen flask combustion method and X-ray photoelectron spectroscopy. It was shown that for samples with total chlorine content of up to 6%, there was almost no leaching of chlorine from the samples. The chemical structure of the extracted rubbers was ascertained using FT-IR and 1H NMR spectroscopy, and it was demonstrated that all samples showed absorption peaks and signals typical for chlorobutyl rubbers. It was observed that modification with polychlorinated n-alkanes improved the thermal and oxidative stability (the oxygen absorption rate decreased by 40%) and chemical resistance, estimated by the degree of swelling, which decreased with the increase in the chlorine content. This technology allows the production of a chlorinated rubber solution that can be directly used by rubber goods manufacturers and suppliers.

Effects of Nanofillers and Synergistic Action of Carbon Black/Nanoclay Hybrid Fillers in Chlorobutyl Rubber

“…CIIR and BIIR have better gas and steam impermeability, resistance, and chemical inertia than butyl rubber, which is affected by halogen. CIIR has a chlorine concentration of 1.1% to 1.3% and an unsaturation degree of 1.8 mol [48,49]. CIIR is ideal for pressure marking and rubber combinations because of its high performance in several key areas: low permeability, vibration damping, ageing resistance, and a low glass transition temperature [46,50], and its excellent processing qualities can withstand high temperatures.…”