Adjusting Some Properties of Poly(methacrylic acid) (Nano)Composite Hydrogels by Means of Silicon-Containing Inorganic Fillers

Abstract

The present work aims to show how the main properties of poly(methacrylic acid) (PMAA) hydrogels can be engineered by means of several silicon-based fillers (Laponite XLS/XLG, montmorillonite (Mt), pyrogenic silica (PS)) employed at 10 wt% concentration based on MAA. Various techniques (FT-IR, XRD, TGA, SEM, TEM, DLS, rheological measurements, UV-VIS) were used to comparatively study the effect of these fillers, in correlation with their characteristics, upon the structure and swelling, viscoelastic, and water decontamination properties of (nano)composite hydrogels. The experiments demonstrated that the nanocomposite hydrogel morphology was dictated by the way the filler particles dispersed in water. The equilibrium swelling degree (SDe) depended on both the pH of the environment and the filler nature. At pH 1.2, a slight crosslinking effect of the fillers was evidenced, increasing in the order Mt < Laponite < PS. At pH > pKaMAA (pH 5.4; 7.4; 9.5), the Laponite/Mt-containing hydrogels displayed a higher SDe as compared to the neat one, while at pH 7.4/9.5 the PS-filled hydrogels surprisingly displayed the highest SDe. Rheological measurements on as-prepared hydrogels showed that the filler addition improved the mechanical properties. After equilibrium swelling at pH 5.4, G’ and G” depended on the filler, the Laponite-reinforced hydrogels proving to be the strongest. The (nano)composite hydrogels synthesized displayed filler-dependent absorption properties of two cationic dyes used as model water pollutants, Laponite XLS-reinforced hydrogel demonstrating both the highest absorption rate and absorption capacity. Besides wastewater purification, the (nano)composite hydrogels described here may also find applications in the pharmaceutical field as devices for the controlled release of drugs.

Novel Green Crosslinked Salecan Hydrogels and Preliminary Investigation of Their Use in 3D Printing

“…As a result, loss modulus covered a range of 10 Pa to 4000 Pa, while storage modulus varied between 2500 and 25,000 Pa. This fact indicates the crosslinked behavior of the salecan hydrogels prepared with citric acid [ 53 , 54 ]. Moreover, these results indicated that the elastic character of the synthesized hydrogels ruled over the viscous character [ 55 ].…”

Zinc Oxide–Incorporated Chitosan–Poly(methacrylic Acid) Polyelectrolyte Complex as a Wound Healing Material

“…It is noted that the -OH band narrowed in the CPMAZnO film due to the development of intermolecular hydrogen bonding and the electrostatic attraction among the two polymer chains. Moreover, the presence of an absorption band at 619 and 1409 cm −1 indicated the successful incorporation of ZnO particles within the CPMA film [9]. The crystalline structure of CPMAZnO films was analyzed and correlated with th of chitosan, PMA, and CPMA films using the XRD technique.…”

“…Currently, poly(methacrylic acid) (PMA) has been widely considered for biomedical applications due to its nontoxicity and biocompatibility. Due to the presence of abundant carboxyl groups, PMA can be chemically modified or conjugated with other biomaterials to extend its functionality as bioactive material [9]. The antibacterial property, which is essential for effective wound healing, can be obtained by incorporating metal oxide nanoparticles in the matrix of PECs.…”

Recent Advances in Synthesis, Characterization and Applications of Innovative Materials in Removal of Water Contaminants

“…The study of Ninciuleanu et al [11], focusing on the impact of adjusting some properties of poly (methacrylic acid) (nano) composite hydrogels by means of silicon-containing inorganic fillers, was also included in this Special Issue. The effect of these fillers, in correlation with their characteristics, structure and swelling, as well as the viscoelastic and water decontamination properties of (nano)composite hydrogels, were studied comparatively [11]. The experiments demonstrated that the nanocomposite hydrogel morphology was determined by the way the filler particles were dispersed in water [11].…”

“…The effect of these fillers, in correlation with their characteristics, structure and swelling, as well as the viscoelastic and water decontamination properties of (nano)composite hydrogels, were studied comparatively [11]. The experiments demonstrated that the nanocomposite hydrogel morphology was determined by the way the filler particles were dispersed in water [11]. The structure of poly (methacrylic acid) hydrogels was also affected by the reinforcing agent through the pH of its aqueous dispersion [11].…”