Preparation and swelling behaviors of porous hemicellulose‐g‐polyacrylamide hydrogels

Abstract

Novel porous hydrogels were successfully synthesized from hemicelluloses (HCs) and acrylamide (Am) with poly(ethylene glycol) (PEG) as the porogen. The prepared hydrogels were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy (SEM). The results show that the used PEG was not involved in the formation process of the hydrogels, and the HC-g-polyacrylamide hydrogels displayed a higher thermal stability than the hemicellulosic polymer. SEM analysis confirmed that the prepared hydrogels had porous structures. The effects of the Am/HC ratio, the amount and molecular weight of PEG and the amount of the crosslinker N,N-methylene bisacrylamide on the swelling ratio of the prepared hydrogels were investigated in detail. The experimental data were fitted with the exponential heuristic equation and the Schott second-order dynamic equation. The diffusion of water molecules into the hydrogel network was found to be non-Fickian in behavior, and the swelling kinetics could be described by the Schott second-order dynamic equation.

4,4′‐Methylenebis(2,6‐di‐t‐butylphenol) as filler in high‐damping chlorinated polyethylene composites

“…Two relaxation regions and three regions resembling the behavior of a plateau can be seen in Figure . In the glass transition region, the curves gradually shift in the direction to the higher temperature and a higher modulus is measured, which are probably related to the additive effect and the forming of network between CPE and AO‐4426 . However, the E ′ value in the elastic regions of the hybrids significantly decreases with the increase of AO‐4426 content, which indicates a reduction of entanglements (or junction points).…”

“…At the same time, the magnitude of the first peak decreases with the increase of AO‐4426, which is probably due to the decrease in CPE content in the hybrids. The first glass transition temperature of CPE/AO‐4426 shifts to higher temperature compared with CPE, probably due to the formation of hydrogen bonds between the hydroxyl groups of AO‐4426 and the chains of CPE . Compared with CPE, the second peak exhibits a dramatic increase.…”

“…Therefore, CPE is regarded as a high‐performance, high‐quality special rubber. Moreover, the polarity segment in CPE contributes to form the hydrogen bond network between CPE and AO‐4426, broaden the damping temperature range, and improve the damping peak . Besides that, the Cl elements in CPE bring good fire retardancy and oil resistivity for the materials.…”

“…In recent years, a number of small molecules have been used as additive into CPE to obtain composites with better properties. Tetrakis‐[methylene‐3‐(3‐5‐di‐tert‐butyl‐4‐hydroxyphenyl)propionyloxy]methane (AO‐60), triethylene glycol bis[3‐(3‐ tert ‐butyl‐4‐hydroxy‐5‐methylphenyl)propionyloxy] (AO‐70), 3,9‐bis [1,1‐dimethyl‐2{β‐(3‐ tert ‐butyl‐4‐hydroxy‐5‐methylphenyl)propionyloxy}‐ethyl]‐2,4,8,10‐tetraoxaspiro[5,5]‐undecane (AO‐80), and 2,2′‐methylenebis(6‐t‐butyl‐4‐methyl‐phenol) (AO‐2246) can improve the damping property of CPE and other polar polymers, such natural rubber, polyurethane elastomer, and nitrile‐butadiene rubber . Particularly, Wu et al .…”

Synthesis and characterization of acrylamide-based copolymeric hydrogel–silver composites: Antimicrobial activities and inhibition kinetics against E. coli

“…Hydrogels are three-dimensional crosslinked polymeric materials that can absorb large amounts of water without undergoing dissolution [1][2][3]. The swelling rate can be controlled by hydrophilicity and crosslink density of polymer [4][5][6].…”