Synthesis and characterization of alginate‐g‐vinyl sulfonic acid with a potassium peroxydiphosphate/thiourea system

Abstract

Alginate-g-vinyl sulfonic acid graft copolymer was synthesized through the graft copolymerization of vinyl sulfonic acid (VSA) onto alginate with an efficient system, i.e., potassium peroxydiphosphate (PDP)/thiourea in an aqueous medium. The effects of the concentration of thiourea, PDP, hydrogen ion, alginate, and VSA along with the time and temperature on the graft copolymerization were studied by the determination of the grafting parameters (grafting ratio, add-on, conversion, grafting efficiency, and homopolymer). The synthesized graft copolymer was characterized by FTIR analysis. Thermogravimetric analysis showed that the alginate-g-vinyl sulfonic acid is thermally more stable than alginate. Water swelling capacity, metal ion sorption, flocculation, and resistance to biodegradability studies of synthesized graft copolymer have been performed with respect to the parent polymer.

Dielectric, thermal, and swelling properties of calcium ion-crosslinked sodium alginate film

“…These thermograms show that SA undergoes thermal degradation in two‐stages. A total of 15 and 20% weight losses for SA2‐Ca40 and SA films, respectively, observed in the temperature range 50–150°C can be attributed to the loss of moisture . Because the polysaccharides have a strong affinity for water, and SA contains two hydroxyl segments and one carboxylate segment, the water molecules can be bound to SA by the hydrophilic COONa and –OH groups.…”

“…Further decomposition of main chain of SA occurs at 450°C . During the thermal decomposition of SA, the carboxylate side chains are eliminated at first from the polymer chain at the temperatures between 200 and 250°C, and then hydroxyl groups beginning from 300°C . For the second step of decomposition, the initial decomposition temperature for SA and SA‐Ca films increases from 190.28 to 195.98°C, respectively.…”

Design Polysaccharides of Marine Origin: Chemical Modifications to Reach Advanced Versatile Compounds

“…The use of CAN as initiator was also described to synthesize a biocopolymer composed of alginate and polymethacrylonitrile under aqueous conditions [150]. Alginate-g-vinyl sulfonic acid graft copolymer was synthesized via the graft copolymerization of vinyl sulfonic acid onto alginate with an efficient system based on potassium peroxydiphosphate and thiourea in an aqueous medium [153]. An initiating system also based on potassium peroxydiphosphate was used towards alginate under inert atmosphere with silver nitrate (AgNO 3 ) to polymerize 2-acrylamidoglycolic acid (AGA) that is a class of acrylamides containing -OH, -COOH and -CONH-functional groups [154].…”

Chemical Modification of Marine Polysaccharide (Alginate) By Free-Radical Graft Copolymerization― a Short Review

“…However, the results show that Pb +2 was least absorbed in comparison to four metal ions studied. Sand et al [26] also reported the synthesis of alginate-grafted vinylsulfonic acid (VSA) by radical polymerization using potassium peroxydiphosphate (PDP) and thiourea (TU) redox system. The optimum conditions were (PDP 0.010M, TU 0.0048M, alginate 1.6M, VSA 0.046M at 50 o C for 2hr).…”