Synthesis and Properties of an Ecofriendly Superabsorbent Composite by Grafting the Poly(acrylic acid) onto the Surface of Dopamine-Coated Sea Buckthorn Branches

Abstract

With the purpose of decreasing production costs and mitigating negative effects on the environment, an ecofriendly superabsorbent composite (SB@PDA/PAA) was synthesized by grafting poly­(acrylic acid) onto the surface of dopamine-coated waste sea buckthorn branches. The structure of the obtained products was analyzed using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The effects of pH level, salt concentration, cation type, and reswelling time on water absorbency were examined further. The results showed that the swelling behaviors of the superabsorbent composite were highly sensitive to the concentration of salt solution, cation type, and reswelling time. The swelling kinetics of SB@PDA/PAA in distilled water could be fitted well with a pseudo-second-order kinetic model. Moreover, the SB@PDA/PAA superabsorbent composites exhibited excellent water-retention properties and achieved a high degradability of 33.5 wt % when they were soaked in a soil solution for 90 days. On the basis of these investigations, it is believed that the obtained SB@PDA/PAA could have potential applications in agricultural or industrial areas because of their water superabsorption and retention capacities, high reswelling capability, and cost-effective and ecofriendly preparation and use. The proposed technology can also be extended to the synthesis of other natural biological resources and organic hybrid materials with similar structures.

Removal of Oil From Water Surface by Novel Composite NSM‐g‐P(MMA‐co‐BA) Super Oil‐Absorption Resin

“…Furthermore, the sorption capacities of resins had an inconspicuous change by varying the concentrations of NaCl solutions from 0.3 wt% to 0.9 wt%. The causes lie in that the resin has the substantial oleophilic and lipophilic groups, which hardly react with water, Na + ions and Cl − ions . As a result, the synthesized resins showed a higher velocity for oil rather than 0.9 wt% NaCl solutions and distilled water in sorption progress.…”

“…The composite may be recycled and reused in theory in oil absorption tests . To further confirm this hypothesis, we subsequently performed the following behaviors: the dried sample (0.1 g) in a stainless steel mesh was immersed in four different oils (20 mL) at room temperature to reach sorption equilibrium.…”

“…The swollen samples then were centrifuged at 4,200 rpm for 50 min and dried in an oven at 45°C for 40 h, respectively. The oil retention of composite resins at several times intervals was calculated using formula (2) : …”

“…In order to achieve above‐mentioned objectives, the environmental‐friendly and renewable natural oil‐absorption materials, such as poplar , cotton , wool fibers , kapok fiber , and sea buckthorn branches have been proposed currently to partially combine the conventional petroleum‐based polymers for purpose of construction of composite super oil‐absorbent materials. Widely adopted monomers, including methyl‐meth‐acrylate and butyl‐acrylate, have been successfully grafted onto the surface of natural oil‐absorbent of plant fibers .…”

Eco-friendly and cost-effective superabsorbent sodium polyacrylate composites for environmental remediation

“…They can absorb solutions quickly by swelling porous structure networks to reduce mass-transfer resistance, and different functional groups (e.g., hydroxy, carboxylic acid, amine, amidoxime, and sulfonic acid groups) are present on the polymer chains that enable coordination and chelation with the metal ions [13,14]. Due to their low-cost, non-toxicity, and biocompatibility, SAPs with different natural and synthesized fillers have been widely used in water purification and applications for the recovery of metal ions [13,[15][16][17]. Zheng et al incorporated starch and humic substances into polymer hydrogels, and a series of starch-g-poly(acrylic acid)/sodium humate (St-g-PAA/SH) hydrogels were synthesized for Cu(II) adsorption from the aqueous solution [18].…”