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EN
In free radical polymerization initiated by 2,2’-azobis(2-methylpropionamidine) dihydrochloride, grafted starch copolymers with a weight ratio of acrylamide to acrylic acid of 1:2 were obtained. Three acrylic products were used to cross-linking starch copolymers: MBA, PETIA and EBECRYL 40 in amounts of: 0.2, 0.4, 0.6 and 1.0 wt.%. Materials were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry and reoviscometry. The sorption properties of starch copolymers were confirmed by sorption tests: water absorption, swelling in water and sorption of cations: trivalent iron and divalent copper. The highest water absorption is characteristic of materials cross-linked with MBA (1800%), then PETIA (1400%) and EBECRYL 40 (850%). On the other hand, the best swelling results are in the sequence PETIA > MBA > EBECRYL (1050% > 900% > 570%). The most effective sorbent of cations is the copolymer cross-linked with MBA. Solution purifications of 90% and 45% were obtained for Fe+3 and Cu+2, respectively.
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EN
Starch graft copolymers have been obtained via grafting of acrylic monomers i.e. acrylamide (AAm) and acrylic acid (AA) during the reactive extrusion processes. 2,2'-azobis (2-methylpropionamidine) dihydrochloride (AAPH) was used as a radical initiator and N'N-methylenebisacrylamide (MBA), mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (trade name PETIA) and alkoxylated pentaerithritol acrylate (trade name Ebecryl 40) were applied as acrylic crosslinkers. The obtained materials were characterized by FTIR and their water sorption properties investigated using swelling (vol. %) and sorption (wt. %) tests. Sorption of water into these graft copolymer samples reached values of ca. 6-13 g of water per g of dry materials. It was also found that water sorption values were dependent on ratio of AAm and AA as well as on a type of the applied crosslinking agent.
EN
Nanocomposite flocculants based on polyacrylamide-grafted starch copolymers with carbon nanotubes (PAM-St-CNT) were prepared using natural polymer – potato starch (St), acrylamide (AM) as monomer and CNTs by in situ polymerization process. The effect of monomer to starch molar ratio, dose of flocculants and content of CNTs in composition on flocculation efficiency were investigated. All materials were characterized by FT-IR (Fourier transform infrared spectroscopy), TGA (thermogravimetric analysis) and DSC (differential scanning calorimetry) methods. An aqueous suspension of kaolin was used for the flocculation studies. The flocculation effectiveness was evaluated on the basis of reduction of suspension absorption and the sludge volume. It was found that synthesized nanocomposites PAM-St-CNT exhibit satisfactory flocculating properties.
PL
Z zastosowaniem naturalnego polimeru – skrobi ziemniaczanej (St) – akryloamidu (AM) jako monomeru i nanorurek węglowych (CNTs) w procesie polimeryzacji in situ wytworzono nanokompozytowe poliakryloamidowe kopolimery szczepione skrobi z nanorurkami węglowymi (PAM-St-CNT) do wykorzystania w charakterze flokulantów. Badano zależność wydajności flokulacji od stosunku molowego monomeru do skrobi oraz dodatku flokulantów i zawartości CNTs w materiale. Otrzymane układy scharakteryzowano metodami spektroskopii w podczerwieni z transformacją Fouriera (FT-IR), analizy termograwimetrycznej (TGA) i różnicowej kalorymetrii skaningowej (DSC). Do testów flokulacyjnych zastosowano wodną zawiesinę kaolinu. Skuteczność flokulacji oceniono na podstawie zmian absorpcji zawiesiny modelowej i objętości osadu poflokulacyjnego. Stwierdzono, że zsyntetyzowane nanokompozyty PAM-St-CNT wykazują zadowalające właściwości flokulacyjne.
EN
Starch graft copolymers have been obtained via grafting of acrylic monomers i.e. acrylamide (AAm) and acrylic acid (AA) during the reactive extrusion processes. 2,2'-azobis (2-methylpropionamidine) dihydrochloride (AAPH) was used as a radical initiator and N'N-methylenebisacrylamide (MBA), mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (trade name PETIA) and alkoxylated pentaerithritol acrylate (trade name Ebecryl 40) were applied as acrylic crosslinkers. The obtained materials were characterized by FTIR and their water sorption properties investigated using swelling (vol. %) and sorption (wt. %) tests. Sorption of water into these graft copolymer samples reached values of ca. 6 – 13 g of water per g of dry materials. It was also found that water sorption values were dependent on ratio of AAm and AA as well as on a type of the applied crosslinking agent.
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