Synthesis and Properties of Anion Exchangers Derived from Chloromethyl Styrene Codivinylbenzene and Their Use in Water Treatment

Abstract

Amination of vinylbenzyl chloride-divinylbenzene (VBC-DVB) copolymers is an effective method for preparation of ion-exchange resins. Conventionally, the starting polymer is produced by chloromethylation of a styrene-divinylbenzene copolymer that utilizes chloromethyl methyl ether, a known carcinogen. An alterative approach is to copolymerize vinylbenzyl chloride with divinylbenzene to generate the necessary VBC-DVB. This method provides precise control over the density of the ion-exchange groups. The regiochemistry of the vinylbenzyl chloride methods was realized using solvent-ion exchange groups. In this investigation, an improved solvent system was found for the preparation of anion exchange resins by the vinylbenzyl chloride route. The effectiveness of amination of the intermediate VBC-DVB polymers with a variety of trimethylamine reagents was investigated, and ethanolic trimethylamine produced the highest degree of amination. These resulting ion-exchange polymers were characterized by a variety of techniques such as analytical titrations, nitrogen analysis, Fourier transform infrared spectroscopy and thermal gravimetric analysis. Testing of these copolymers for breakthrough was performed. The results indicate that these anion exchangers have a meaningful increase in thermal stability over commercial anionic exchange beads.

Poly(vinylbenzyl chloride-glycidyl methacrylate)/Polyethylene Composite Anion Exchange Membranes for Vanadium Redox Battery Application

“…It was also observed that the peaks at 1797 cm −1 and 910 cm −1 were respectively assigned the carbonyl (>C=O) and epoxy (-COC-) stretching vibration band as a characteristic of GMA (curve (c)). 16 These observations show that the VBC and GMA copolymer was successfully synthesized and that the amine group was introduced to the base polymer through the functionalization process.…”

Effect of styrene addition on chemically induced grafting of 4‐vinylbenzyl chloride onto low‐density polyethylene for anion exchange membrane preparation

“…These are attributed to the O–H bond and quaternary ammonium in the anion exchange membranes . The absorption bands between 800 and 900 cm −1 are also claimed to be associated with quaternary ammonium groups by some researchers . Absorption peaks at 1266 and 823 cm −1 that are attributed to –CH 2 Cl in P(VBC) disappeared in aminated membranes, demonstrating that chlorine atoms were completely substituted by quaternary ammonium cations.…”

“…A new peak observed at 1266 cm −1 is due to C–H wag of terminal alkyl halides, –CH 2 Cl. C–Cl stretching in VBC is observed at 823 cm −1 . When St was added to the reaction as a comonomer, new peaks started showing at 1478 and 701 cm −1 in LDPE‐ graft ‐P(St‐ co ‐VBC).…”

“…PE‐ graft ‐PS based anion exchange membranes were traditionally synthesized by grafting styrene (St) onto PE followed by chloromethylation and amination . In order to bypass the chloromethylation step which requires use of carcinogenic chloromethylating reagents such as chloromethyl ether and chloromethyl ethyl ether, researchers used an alternative method of grafting 4‐vinylbenzyl chloride (VBC) onto PE .…”

Preparation and Characterization of Homopolymer Polyacrylonitrile-Based Fibrous Sorbents for Arsenic Removal

“…After 12 h, the uptake of Ca 2 + ions from the solutions was measured using a PerkinElmer Optima 2100 DV inductively coupled plasma optical emission spectrometer (ICP-OES). For determination of the AEC, 0.1 g of fiber (free base form) was shaken in 25 mL of 0.1 M HCl solution at 25°C for 12 h (Ezzeldin et al, 2010). The solution was then analyzed for Cl -via titration with a standardized 0.1 M AgNO 3 solution using chromate as an indicator (Zhang et al, 2011).…”