Poly ionic liquid cryogel of polyethyleneimine: Synthesis, characterization, and testing in absorption studies

Abstract

Here, we report the synthesis of polyethyleneimine (PEI) cryogels for the first time via cryopolymerization technique. The crosslinking of amine groups on the branched PEI chains is accomplished with epoxy groups of glycerol diglycidyl ether (GDE) based on epoxy-amine reactions in excess water at 218 8C in about 16 h. Superporous PEI cryogels with pore sizes >100 lm were shown to have very fast equilibrium swelling behavior, e.g., 10 s to reach maximum swelling in DI water. Furthermore, the synthesized PEI cryogels were exposed to anion exchange reaction after protonation by HCl treatments to generate PEI ionic liquid cryogels containing hexafluorophosphate, thiocyanate, dicyanamide, and tetrafluoroborate. It was also demonstrated that PEI cryogels modified with [PF 6 ] 2 absorbed 47.8 6 5.7 mg/g of bovine serum albumin (BSA). Moreover, PEI cryogels were shown to be very useful as simple filtration filling materials for the direct removal of organic dyes such as methyl orange (MO) and eosin Y (EY) from their corresponding aqueous solutions with 98.5 and 98.6% yields, respectively. The separation of methylene blue (MB) from MO and EY mixture by using PEI cryogels as column filler materials was also demonstrated.

Properties of conductive polymer hydrogels and their application in sensors

“…The excellent sensitivity of the sensor is due to the enhanced adsorption of a NH 3 and NO 2 molecules by functional groups (e.g., ─OH, ─NH 2 , and SO 3 − ) on the hydrogel . Conductive polymer cryogel composites with super and interconnected porosity and fast response to stimuli are often preferred as smart responsive materials . Based on the gas‐sensitive conductivity change, they can be used in highly sensitive gas sensor applications .…”

Polyethylenimine‐Based Nanogels for Biomedical Applications

“…[31] For instance, Li et al reported the preparation of bioreducible NGs by electrostatic complexation between the phenolic groups of tannic acid (TA) and the positive charged amine groups of PEI. [32] In their approach, PEI was dissolved in Triton X100/gasoline, then mixed with the water solution of TA with a weight ratio of 1:1 under constant magnetic stirring for 15 min. After being precipitated in acetone and centrifuged at 10 000 rpm at room temperature, TA-PEI NGs with a size range of 0.5-5 µm were obtained (Figure 2a).…”

“…Reproduced with permission. [32] Copyright 2016, Elsevier Ltd. b) Synthetic procedure to obtain biohybrid NGs via crosslinking in W/O emulsion. Reproduced with permission.…”

Conductive polymer containing graphene aerogel composites as sensor for CO2

“…In in situ synthesis of poly(pyrrole) (PPy) within 3D GAs, the same method that is reported for cryogels was also used with some modifications [39,41]. For this purpose, cleaned and dried 3D GAs weighing 0.5 g were placed into 20 mL pyrrole (Py, 98%, Aldrich) to load Py monomer into 3D GAs for 30 min.…”