Graft polymerization of acrylamide onto maize starch using potassium persulfate as initiator

Abstract

Graft polymerization of acrylamide (Aam) onto maize starch using potassium persulfate as initiator was investigated under different conditions including concentration of initiator and monomer, polymerization time and temperature and liquor ratio. Based on the results obtained, appropriate conditions for grafting acrylamide onto starch were established. These conditions were also used for grafting other monomers onto maize starch. Results obtained indicate that acrylamide acquires the highest graft ability while acrylic acid acquires the least, while acrylonitrile and methacrylic acid in between. The water solubility of both nitrogen-and carboxy-containing copolymers increases by increasing the monomer content up to a certain value, then it decreases. ZUSAMMENFASSUNG:Die Pfropfcopolymerisation von Acrylamid (Aam) auf Maisstarke wurde mit Kaliumpersulfat als Initiator bei unterschiedlichen Reaktionsbedingungen, wie Initiatorbzw. Monomerkonzentration, Reaktionszeit und -temperatur sowie dem Feststoffgehalt untersucht. Basierend auf den erhaltenen Ergebnissen wurden die geeignetsten Bedingungen ausgewahlt und den Pfropfpolymerisationen von anderen Monomeren auf Maisstarke zugrundegelegt. Von den eingesetzten Monomeren zeigte Acrylamid die grorjte Pfropffahigkeit, Acrylsaure die geringste; Acrylnitril und Methacrylsaure lagen dazwischen. Die Wasserloslichkeit sowohl von stickstoffhaltigen als auch von Carboxygruppen enthaltenden Copolymeren steigt zunachst mit steigendem Monomergehalt an und sinkt ab einem bestimmten Wert wieder.

Influence of Chain Structures of Starch on Water Absorption and Copper Binding of Starch‐Graft‐Itaconic Acid Hydrogels

“…The modification of starch via the grafting of vinyl monomers is a highly effective way of synthesizing superabsorbent polymers. Monomers such as acrylic acid, acrylamide, and acrylonitrile have been used to this end. The graft copolymers have been used to make hydrogels, flocculants, and ion exchangers .…”

Modification of carbohydrate polymers via grafting of methacrylonitrile onto pregelled starch using potassium monopersulfate/Fe2+ redox pair

“…It is well known that graft copolymerization of synthetic vinyl monomers onto starch as a carbohydrate polymer is a promising means of producing substantial modification in starch properties thereby enlarging the field of its potential applications 1–7. The properties of the resulting copolymers may be widely controlled by the characteristics of side chains, including molecular structure, length and number.…”

“…The properties of the resulting copolymers may be widely controlled by the characteristics of side chains, including molecular structure, length and number. Starch graft copolymers could be achieved primarily by free radical initiation processes,1, 3, 5, 8 which include transition ions such as Fe 3+ , V 3+ , Mn 3+ , Ce 3+ , Cu 2+ as well as their complexes 9–11. On the other hand, according to Hebeish et al , poly(methacrylic acid) (MAA)‐starch graft copolymer is the main product of the polymerization reaction only when starch is preswelled prior to grafting 12.…”

Eco‐Friendly Synthesis of Hydrogels from Starch, Citric Acid, and Itaconic Acid: Swelling Capacity and Metal Chelation Properties

“…Starch has also been used for the production of superabsorbent hydrogels, in particular through the grafting of vinyl monomers . While this allows hydrogels to remain biodegradable, it does have drawbacks as well.…”