The Role of FeSO4 in the Obtaining of Polyvinylpirrolidone Copolymers

Abstract

Abstract. The proceeding of 2-hydroxyethylmethacrylate grafted polymerization on polyvinylpirrolidone has been examined in the presence of ferrum(II) sulfate. It was observed the formation of crosslinked copolymer capable to be used as a matrix for metal chemical reduction and for metal hydrogel composites obtaining. The effect of Fe n+ structure and concentration on the structural parameters of the polymeric network, copolymers composition, efficiency and degree of grafting has been determined. The interaction between the structure of the synthesized copolymers and their thermal and physicomechanical properties has been established.

Hydrogels Based on Polyvinylpyrrolidone Copolymers

“…In general, it is assumed that hydrogels based on the structured hydroxyalkyl (meth)acrylates contain 20-40% of water. It has been stated [52] that the amount of sorbed water for such hydrogels depends on the degree of polymeric matrix cross-linking or on the molecular weight of the polymeric grid fragment between nodes.…”

“…By the method of free-radical thermopolymerization of water-soluble hydroxyalkyl (meth) acrylates in aqueous solution using water-soluble or alcohol-soluble peroxide initiators, at the temperature of 50-70°C. In this case, network structural parameters and water amount in the hydrogel depend on the amount of water in the reaction mass (Table 4) [20,52] Based on the reactivity of HEMA:PVP composition, a stable hydrogel can be formed in the process of polymerization in water solution when the amount of aqueous is two to three times higher than the mass of composition that forms polymeric matrix. Resulting hydrogel does not release excess of water due to its high sorption ability of PVP-based polymeric matrix and significantly smaller ratio of macrochain crosslinks ( Table 5).…”

Термометричні Дослідження Полімеризації 2-Гідроксіетилметакрилату В Присутності Полівінілпіролідону З Одночасним Відновленням Йонів Нікелю

“…Одним із методів здійснення полімеризації ГЕ-МА/ПВП композицій за низьких температур є полімеризація у присутності FeSO 4 (Suberlyak, Grytsenko & Kochubei, 2015). Під дією йонів металів змінного ступеня окиснення процес відбувається з високою швидкістю за кімнатної температури, на повітрі та завершується через 5-10 хв.…”

Technological features in obtaining highly effective hydrogel dressings for medical purposes

“…Water content (W, %), hardness number (Н, МPа), plasticity number (Р, %), elasticity number (Е, %) were determined using the procedures described in [22].…”

“…However, due to the high rate of heat release and poor thermal conductivity of the polymer, there occurs thermal expansion and occurrence of internal stresses, which is the cause of cracking in the volume of the sample [21]. Polymerization in the presence of FeSO 4 is one of the methods of polymerization of PVP-HEMA of the compositions at low temperatures [22]. Under the influence of metal ions of the alternating degree of oxidation, the process occurs at a high rate at the room temperature, in the air and finishes after 5-30 minutes.…”