Synthesis and characterization of a dewatering reagent: cationic polyacrylamide (P(AM–DMC–DAC)) for activated sludge dewatering treatment

A facile method was explored to synthesize thermosensitive poly[N‐isopropylacrylamide (NIPAM)‐co‐methacryloxyethyltrimethyl ammonium chloride (DMC)]/Na2WO4 cationic hydrogels via copolymerization of NIPAM and DMC in the presence of Na2WO4. Na2WO4 acted as both a physical crosslinking agent and a porogen precursor. The hydrogels were characterized by Fourier transform infrared spectroscopy, energy dispersive X‐ray, thermogravimetry, environmental scanning electron microscopy, and transmission electron microscopy. Effects of various salt solutions, pH solutions on swelling were investigated. Thermosensitivity of the hydrogels were also investigated in various polar solvents at different temperatures. The resultant hydrogel showed a fast swelling rate and good salt tolerance. The hydrogels reached the swelling equilibrium within 10 min. Moreover, the swelling ratio of the hydrogels increased with the increase of the polarity of the solvent. In the water, the swelling ratio decreased with the increasing of temperature, but remained at a high level even at 80 °C since the pore structure weaken the lower critical solution temperature effect of PNIPAM. The swelling ratio increased instead in low polar solvent, while it became negligible in nonpolar solvent with the increasing of temperature. The whole swelling kinetics was fit for Schott's pseudo‐second order model. The hydrogels have a great potential as catalysts and smart materials. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46375.

Section: Resultsmentioning

confidence: 90%

Fast swelling behaviors of thermosensitive poly(N‐isopropylacrylamide‐co‐methacryloxyethyltrimethyl ammonium chloride)/Na₂WO₄ cationic composite hydrogels

Xiao

Tan

et al. 2018

“…The intermolecular and intramolecular imidization under acidic conditions led to the formation of crosslinked and branched polymers, which was the main reason for the low intrinsic viscosity. In strong alkaline conditions (pH > 10), the amide group of AM hydrolyzed to NH 3 , which further reacted with acrylamide to form nitrilotripropionamide and carbonium ion . Nitrilotripropionamide caused polymerization termination and chain transfer, whereas the electrophile of carbonium ions inhibited polymerization, thereby forming a copolymer with low intrinsic viscosity and conversion.…”

Section: Resultsmentioning

confidence: 99%

“…CPAM polymerization is commonly initiated through heat, rays, microwaves, or ultraviolet (UV) waves. Our previous research indicated that UV initiation has the advantages of easy control, low reaction temperature, short polymerization time, large polymer molecular weight, and environment friendliness …”

Section: Introductionmentioning

confidence: 99%

Preparation, characterization, and flocculation performance ofP(acrylamide‐co‐diallyldimethylammonium chloride) by UV‐initiated template polymerization

Guan

Zheng

Zhai

et al. 2014

Self Cite

This study prepared TPDA, a high‐intrinsic‐viscosity cationic polyacrylamide, through ultraviolet (UV)‐initiated template polymerization. Acrylamide (AM) and diallyldimethylammonium chloride (DMD) served as monomers, and poly sodium polyacrylate (PAAS) served as the template. The structure of TPDA was characterized by Fourier‐transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and thermogravimetric analysis. The synthetic conditions of TPDA were studied and optimized by single‐factor experiments. An optimized product was obtained at an intrinsic viscosity of 11.3 dL g−1 and a conversion rate of 97.2% with a total monomer concentration of 20%, DMD concentration of 30%, initiator concentration of 0.045%, pH of 8, EDTA concentration of 0.3%, and UV irradiation of 90 min. Results showed that TPDA was the copolymer of AM and DMD with a micro‐block structure at the molecular chain. Given its high intrinsic viscosity and cationic block structure, TPDA performed better in kaolin flocculation than that prepared without template addition. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41747.

“…Micellar morphologies of polymers depend on several factors such as molecular weight, polydispersity, composition, functionality, solvent conditions, and the method of preparing the dispersion . Water soluble polyacrylamide and its derivatives have played an important role in biomedical applications, waste water treatment, and nontoxic additives in food and paper industries . Polyacrylamides with well‐defined structures were prepared using controlled living polymerizations, such as nitroxide mediated radical polymerization, atom transfer radical polymerization (ATRP), the reversible addition‐fragmentation chain transfer polymerization, and the cyanoxyl mediated free radical polymerizations …”

Section: Introductionmentioning

confidence: 99%

Synthesis of amine‐functionalized block copolymers for nanopollutant removal from water

Qureshi

Dsouza

Mallampati

et al. 2014

Polyamines are rare in literature owing to increased reactivity, sensitivity to air and moisture, low stability, and processing difficulties. Here, we report the synthesis and characterization of highly processable polyamines and use them for the removal of dissolved metallic nanoparticles from water. Three amphiphilic block polyamines such as poly(N‐aminoethyl acrylamide‐b‐styrene), poly(N‐aminopropyl acrylamide‐b‐styrene), and poly(N‐aminoxylyl acrylamide‐b‐styrene) have been synthesized using atom transfer radical polymerization of ethyl acrylate and styrene followed by aminolysis of the acrylic block. The polymerization and properties of the polymers are studied using different physicochemical techniques. Surface morphology of films prepared from these block copolymers by dissolving in different solvents such as chloroform, tetrahydrofuran and N,N‐dimethylformamide, and drop‐casting polymers on a glass substrate show interesting porous films and spherical nanostructures. In addition, the amine‐functionalized block copolymers have been used for the removal of nanoparticles from water and show high extraction efficiency toward silver (Ag) and gold (Au) nanoparticles. All three amine‐functionalized block copolymers show higher extraction capacities (Qe) toward Au NPs (50–109 mg g−1) and Ag NPs (99–117 mg g−1). Our approach allows us to make amine‐functionalized block copolymers which are stable in air and can be easily processed in nonpolar solvents. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40943.