Effect of Template on Structure and Properties of Cationic Polyacrylamide: Characterization and Mechanism

Abstract

In this study, a cationic block structure with a strong neutralizing ability was formed through template polymerization. Acryloxyethyltrimethyl ammonium chloride (DAC) and acrylamide (AM) were used as monomers, and the ionic homopolymer sodium polyacrylate (NaPAA) was used as the template. The product containing NaPAA after template polymerization is denoted as NTP, whereas the copolymer obtained after removing the NaPAA is denoted as TP. The common polymer (denoted SP) of AM and DAC was copolymerized through solution polymerization. TP and SP were characterized and compared by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), 1 H nuclear magnetic resonance ( 1 H NMR) spectroscopy, and thermogravimetric analysis (TGA). The results of 1 H NMR spectroscopy and TGA showed that a cationic block structure was formed in TP. The mechanism of the cationic block polymer used in water treatment was extensively studied through a jar test in which turbidity, zeta potential, and average floc size were used to evaluate the flocculation performance. The results further supported the cationic block structure of TP. TP, with a different structure than SP, resulting in a stronger neutralization ability, showed a better performance in flocculating kaolin suspensions. The dominant mechanisms for TP flocculation behavior at pH 5, 7, and 9 might be patching, charge neutralization, and bridging adsorption. The flocculation performance of NTP was not acceptable, whereas acidic NTP at pH < 2 showed a flocculation effect similar to that of TP.

Fabricating an anionic polyacrylamide (APAM) with an anionic block structure for high turbidity water separation and purification

“…Thus, a more ragged and hammered surface morphology was observed for TPAS, and which was consistent with the nding in the template copolymerization. 38 …”

Synthesis of a Cationic Polyacrylamide under UV Initiation and Its Flocculation in Estrone Removal

“…The bending vibration of −CH 2 − in −CH 2 −N + group of DAC was at 1453 cm −1 [19]. The bending vibration of −N + −(CH 3 ) 3 in DAC was observed at 961 cm −1 [20]. Compared with PAD, the characteristic adsorption peaks of PADA were observed at 774 and 707 cm −1 , which were assigned to the benzene skeleton vibration in AODBAC [21].…”

“…The resonance peaks for the protons of −O−CH 2 − (c) were observed at 4.61 ppm. The resonance peaks for the protons of −CH 2 −N + (d) group were illustrated at = 3.77 ppm [20]. Besides, the sharp resonance peak at = 4.80 ppm was associated with the protons of solvent D 2 O.…”

Effects of a polymeric organic coagulant for industrial mineral oil wastewater treatment using response surface methodology (RSM)

“…In general, the main mechanism of coagulation is charge neutralisation and bridging of the oil micro-droplet flocs to produce macro-droplet flocs, which depends on the molecular charge and the charge density. Some of the polymers used for coagulation are of low molecular weight with high cationic charge density, for example, hydrolysed polyaluminium sulphate (PAS), polyacrylamide, melamine formaldehydes, polyamine, polyacrylamides (Zetag-FS/A50) and polydiallydimethyl ammonium chloride (polyDADMAC) (Zouboulis and Avranas, 2000;Bolto and Gregory, 2007;Li et al, 2008;Guan et al, 2014;Oliveira et al, 2014;Kweinor Tetteh et al, 2017). There has recently been extensive and ongoing work looking for an alternative coagulant for chemical treatment that is capable of meeting more stringent treatment standards.…”

“…As part of this study, a field study on a local South Africa wastewater treatment process was conducted and an expert consulted at a local water treatment plant reported, based on experience, that Zetag-FS/A50 has super-surfactant merits when applied in treating industrial wastewater. However, it has some drawbacks for the environment when attention is not paid to over-or under-dosage, such as (a) re-dispersion of impurities, (b) increase in sludge formation and (c) high turbidity (Bolto and Gregory, 2007;Guan et al, 2014;Oliveira et al, 2014). It is therefore important to pay attention to the coagulant dosage throughout the treatment process.…”