Poly(vinyl alcohol) (PVA)-Enhanced Hybrid Hydrogels of Hyperbranched Poly(ether amine) (hPEA) for Selective Adsorption and Separation of Dyes

Abstract

The unique selective adsorption of hydrophilic dyes gives the hybrid hydrogels of hyperbranched poly(ether amine) (SiO 1.5 -hPEA-Gels) potential in the separation. We here introduced poly(vinyl alcohol) (PVA) to enhance the mechanical strength of hybrid hydrogels to extend them into the practical application. A series of PVA-enhanced hybrid hydrogels (PVA@SiO 1.5 -hPEA-Gels) were prepared by chemically cross-linking between hydroxyl groups of PVA and trimethoxysilyl groups of hyperbranched poly(ether amine) (TMS-hPEA) in water. The compress stress of PVA@SiO 1.5 -hPEA-Gels increased significantly with the increasing content of PVA. Compared to hybrid hydrogel without PVA, the stress of PVA@SiO 1.5 -hPEA-1/2-Gel containing 33% PVA increased hundreds of times. The adsorption behavior of the obtained PVAenhanced hydrogels to ten hydrophilic dyes was investigated in detail. Regardless of their charge states, PVA@SiO 1.5 -hPEA-Gels exhibited the quick adsorption to Ponceau S (PS), Rose Bengal (RB), Orange G (OG), and Ponceau SX (PSX) with a high adsorption capacity (Q eq ) and very slow adsorption of Bismarck brown Y (BY), Methylene Blue trihydrate (MB), and Rhodamine 6G (R6G) with a low adsorption capacity. The adsorption process was found to follow the pseudo-second-order kinetics, and the introduction of PVA has no obvious effect on the adsorption behavior in this study. The big difference in the adsorption to the different dyes is indicative of the selective adsorption of PVA@SiO 1.5 -hPEA-Gels to dyes. A methodology of dynamic separation of dye's mixtures (PS/BY and OG/MB) in water is finally demonstrated by using PVA@SiO 1.5 -hPEA-Gels.

Chitosan hydrogels for targeted dye and protein adsorption

“…[24] These factors, in addition to the economic and environmental benefits of a material that typically consists of at least 90% water by mass, make polymer hydrogels particularly appealing as substrates for dye adsorption. Synthetic polymers including poly(2-hydroxyethylmethacrylate), [25] poly [2-(methacryloyloxy)ethyl]trimethylammonium chloride [26] and poly(N,N-diethylamino ethyl methacrylate), [27] copolymers including poly(vinyl alcohol)-block-poly(ether amine) [28] and poly(acrylic acid-co-acrylamide), [29] and claymodified poly(acrylic acid) [30] and poly(N-isopropylacrylamide)-based hydrogels [31] have independently been employed for targeted dye adsorption.…”

Super-adsorbent material based on functional polymer particles with a multilevel porous structure

“…The functional groups in the 3D network can equivalently conjugate with target molecules, leading to unique selectivity and remarkable adsorption capacity. [36][37][38] However, for amorphous soft materials such as hydrogels, a relatively long time is required to reach a saturated state of adsorption. Meanwhile, difficulties associated with the regeneration and disposal of hydrogel adsorbents constitute major obstacles for their practical application.…”

Facile synthesis and functionalization of hyperbranched polyglycerol capped magnetic Fe3O4 nanoparticles for efficient dye removal

“…In this study, the removal of cationic dyes from water by Fe 3 O 4 /HPG-COOH NPs was investigated. On the other hand, the removal of dyes from water is of great importance because the dye effluents may cause damage to human and aquatic biota [6,18]. Herein, rhodamine B (RB) and methylene blue (MB) as typical cationic dyes and congo red (CR) as a typical anionic dye were selected for adsorption study.…”