The cell wall of most plant biomass from forest and agricultural resources consists of three major polymers, cellulose, hemicellulose, and lignin. Of these, hemicelluloses have gained increasing attention as sustainable raw materials. In this study, novel pH-sensitive semi-IPN hydrogels based on hemicelluloses and chitosan were prepared using glutaraldehyde as the crosslinking agent. The hemice...

Two metallohydrogels based on an amino acid-based ligand and Zn(II) salts were synthesized. These hydrogels show an uncommon, reversible, time-dependent transformation from the opaque to transparent state. These hydrogels also exhibit gradual dissolution in water (pH ≤ 7) over time. A water-soluble stimulant, caffeine, could be in situ loaded into the hydrogels and slowly released during dissol...

Multi-stimuli responsive hydrogels are synthesized using self-assembled nanomicelles of Pluronic F127 diacrylate triblock copolymer as non-covalent macro-crosslinkers to in situ copolymerize with acrylamide and methyl chloride quaternized N,N-dimethylamino ethylacrylate monomers, generating positively charged hydrogels. These hydrogels showed high strength, toughness, and outstanding fatigue re...

In this study, several examples of hydrogels and nanocomposite hydrogels based on PVP with different content of montmorillonite nanoclay were prepared. Then, the swelling of hydrogels and kinetics of drug delivery of hydrogel in an environment similar to the body (pH 7.4) were examined. The effect of nanoparticle different percentages on the hydrogel was clearly observed. Then kinetics of drug ...

Controlled drug release devices of pH-sensitive, complexing poly(acrylic acid-g-ethylene glycol) (P(AA-g-EG)) hydrogels were prepared by free radical solution UV polymerization. The effects of hydrogel composition, polymerization conditions and surrounding environment on theophylline release kinetics and drug transport mechanisms were evaluated in these P(AA-g-EG) polymer networks. Release stud...

Molecular and structural changes of the P(MAA-g-EG) hydrogels were investigated in their hydrated state using attenuated total reflectance Fourier transform infrared spectroscopy. FTIR studies identified the formation of hydrogen-bonded complexes at low pH and polyelectrolyte complexes at high pH. Hydrogen bonding and electrostatic repulsion were not affected by the grafted PEG molecular weight...

N-isopropylacrylamide (NIPAAM)/maleic acid (MA) copolymeric hydrogels were prepared by irradiating the ternary mixtures of NIPAAM/MA/Water by g-rays at ambient temperature. The influence of external stimuli such as pH and temperature of the swelling media on the equilibrium swelling properties was investigated. The hydrogels showed both temperature and pH responses. The effect of comonomer conc...

Removal of Cd 2+ , Pb 2+ , and Ni 2+ from aqueous solutions using cellulosegraft-acrylic acid (C-g-AA) hydrogels was investigated. Various factors affecting the adsorption capacity, such as pH, time, initial ions concentration, and competitive ions, were tested. The results showed that the adsorption of hydrogels was very pH dependent, and maximum adsorption was obtained at a pH of 5.0. The ads...

A class of new biodegradable hydrogels based on poly(ethylene glycol) methacrylate-graft-poly(glutamic acid) and poly(ethylene glycol) dimethacrylate was synthesized by photoinduced polymerization. Because all the polymeric constituents were highly hydrophilic, crosslinking could be performed in aqueous solutions. This type of crosslinked hydrogel was prepared by modifying a select number of ac...

A technique for synthesizing biocompatible hydrogels by cross-linking calcium-form poly(γ-glutamic acid), alginate sodium, and Pluronic F-127 was created, in which alginate can be cross-linked by Ca(2+) from Ca-γ-PGA directly and γ-PGA molecules introduced into the alginate matrix to provide pH sensitivity and hemostasis. Mechanical properties, swelling behavior, and blood compatibility were in...