Allylpolyethoxy Carboxylate Research Articles

Scale Inhibition by a Carboxylate-Terminated Double-Hydrophilic Block Copolymer in Industrial Recycling Water

Acrylic acid (AA)-allylpolyethoxy carboxylate (APEL) copolymer was synthesized. The performance of AA-APEL on inhibition of Ca3(PO4)2, CaCO3 and CaSO4 precipitation was compared with that of current commercial inhibitors. It was shown that AA-APEL exhibited excellent ability to control inorganic minerals, with approximately 95.6% CaSO4 inhibition and 99.8% Ca3(PO4)2 inhibition at levels of 3 and 6 mg/L, respectively. AA-APEL also displayed ability to prevent the formation of CaCO3 scales. Surface morphology characterization of Ca3(PO4)2, CaCO3 and CaSO4 was investigated with scanning electronic microscopy. The inhibition mechanism was proposed that the formation of the excellent solubility of AA-APEL-Ca complexes due to high hydrophilic PEG segments in the AA-APEL matrix.

Double-hydrophilic block copolymer as an effective and green scale inhibitor in industrial recycling water systems

In an attempt to control CaCO3 deposits in industrial recycling water systems, the performance of acrylic acid (AA)–allylpolyethoxy carboxylate (APEL) copolymer as an economical and environmentally friendly inhibitor have been investigated by static experiments, scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The experimental results revealed that AA–APEL (acrylic acid–allylpolyethoxy carboxylate copolymer) achieved the maximum scaling inhibition efficiency of 99.1%. The results of SEM and XRD studies revealed that both the morphology and aggregation of calcium carbonate crystals had been changed, when the inhibitor was added. Moreover, the results of TGA further confirmed the scaling mechanism of the copolymer.

Maleic anhydride–allylpolyethoxy carboxylate copolymer as an effective and environmentally benign inhibitor for calcium carbonate in industrial cooling systems

For the control of calcium carbonate scales, a novel environmentally friendly type of scale inhibitor MLn was synthesized.

Acrylic acid–allylpolyethoxy carboxylate copolymer as a environmentally friendly scale inhibitor (part II)

A novel environmentally friendly type of scale inhibitor acrylic acid–allylpolyethoxy carboxylate (AQn) was synthesized. The antiscale property of the AQn copolymer towards Ca3(PO4)2 in the artificial cooling water was studied through static scale inhibition tests, The observation shows that Ca3(PO4)2 inhibition increases with increasing the degree of polymerization of AQn from 5 to 15, and the dosage of AQn plays an important role on Ca3(PO4)2 inhibition. The effect on the formation of Ca3(PO4)2 was investigated with combination of scanning electronic microscopy, transmission electron microscopy, X-ray powder diffraction analysis, respectively. Inhibition mechanism is proposed that the interactions between calcium ions and polyethylene glycol are the fundamental impetus to restrain the formation of the scale in cooling water systems.

Calcium sulfate precipitation studies with fluorescent-tagged scale inhibitor for cooling water systems

This study focuses on the effect of a water-soluble copolymer, acrylic acid–oxalic acid–allylpolyethoxy carboxylate–8-hydroxy-1,3,6-pyrene trisulfonic acid trisodium salt (pyranine) (AA–APEM–APTA). APEM and APTA were copolymerized with acrylic acid (AA) to synthesize APTA tagged no phosphate and nitrogen-free calcium sulfate inhibitor AA–APEM–APTA. Structures of AA–APEM–APTA were evaluated by FT-IR and 1H-NMR, and oxalic acid, APEG and APEM by C13-NMR. The observation shows that the dosage of AA–APEM–APTA plays an important role in CaSO4 inhibition. The performance of copolymer on inhibition of CaSO4 precipitation was compared with that of current commercial inhibitors. It was shown that the copolymer exhibited excellent ability to control inorganic minerals, with approximately 96 % CaSO4 inhibition. The relationship between AA–APEM–APTA’s fluorescent intensity and its dosage was studied. The correlation coefficient R 2 of AA–APEM–APTA is 0.9999. The effect on formation of CaSO4 was investigated with a combination of scanning electronic microscopy and transmission electron microscope analysis. AA–APEM–APTA can be used safely in cooling water systems.

Inhibition of calcium carbonate and sulfate scales by a non-phosphorus terpolymer AA-APEY-AMPS

The inhibition of calcite crystal growth by acrylic acid-allylpolyethoxy carboxylate-2-acrylamido-2-methyl-propanesulfonic acid (AA-APEY-AMPS, PAYS for short) was investigated in the cooling-water system. The terpolymer was prepared via the copolymerization of acrylic acid (AA), allylpolyethoxy carboxylate (APEY) and 2-acrylamido-2-methyl-propanesulfonic acid (AMPS), whose structures were characterized by FTIR and 1H NMR. In this study, we have investigated the effect of the agent concentration and the ratio of the reactant. The experimental results show that AA-APEY-AMPS is an effective chelating scale inhibitor and it has high efficiency toward scales and nearly 90% for calcium carbonate and 100% for calcium sulfate. The produced crystals were characterized by using scanning electron microscopy and X-ray diffraction methods. It appears that the crystal shape, size, and the morphology of scale have changed apparently at the dosage of 5 mg/L. Based on the contrast experiment of the problem of scale formation, this paper analyses the mechanism of scale formation and the advantage of PAYS. The supporting mechanism of scale formation was also described and analyzed briefly.

Preparation and evaluation of nonphosphate terpolymer as scale inhibitor and dispersant for Ca3(PO4)2, BaSO4, and Iron (III) hydroxide scales

ABSTRACTThe polymeric scale inhibition and dispersion agents (PAYS) were prepared by graft copolymerization of acrylic acid, allylpolyethoxy carboxylate (APEY) and 2‐acrylamido‐2‐methyl‐propanesulfonic acid by using ammonium persulfate as a radical initiator in aqueous solution, among which APEY was synthesized in laboratory. Structure of PAYS was characterized by Fourier transform infrared spectroscopy. Experimental data showed that the terpolymer was a high‐efficient chelate sorbent, and it exhibited excellent ability for calcium orthophosphate, with approximately 96% efficiency at the dosage of 4 mg/L, as well as high efficiency toward barium sulfate scales nearly 80% inhibition. The effectiveness of PAYS depends on the agent concentration, temperature and the ratio of the reactant. The formation of Ca3(PO4)2 and BaSO4 precipitates was characterized by scanning electron microscopy. It appeared that the crystal shape, size, and the morphology of scale changed apparently at the dosage of 4 and 15 mg/L, respectively. In addition, it has good effect on controlling iron (III) scaling. This study was also devoted to the understanding of the action mechanism of these inhibitors in suppressing the crystal nucleus formation and preventing the crystal growth. Based on the contrast experiment of scale formation, the supposing mechanism diagram was also delineated and analyzed in detail. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41546.

Preparation and properties of a polyether‐based polycarboxylate as an antiscalant for gypsum

ABSTRACTA polyether‐based copolymer of acrylic acid‐allylpolyethoxy maleic carboxylate (AA‐APEY) was prepared by copolymerization of allylpolyethoxy carboxylate (APEY) and acrylic acid (AA) at different mole ratios. The main aim of this work was to investigate the influence of AA‐to‐APEY mole ratios on the copolymer properties and scale inhibition performance for gypsum. The synthesized copolymer was characterized by Fourier‐transform infrared (FT‐IR) and further conformed by 1H NMR. The effect of AA‐APEY on controlling calcium sulfate deposits was studied through static scale inhibition tests under standard solution conditions. And the result was compared with that of other polycarboxylates, which are similar to AA‐APEY in structure. Scanning electronic microscopy (SEM), transmission electron microscopy (TEM), and X‐ray powder diffraction (XRD) analysis were carried out to study the morphology and structure changes of calcium sulfate crystals in the presence of AA‐APEY. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40193.

A multicarboxyl antiscalant for calcium phosphate and calcium carbonate deposits in cooling water systems

AbstractA “green” antiscalant of acrylic acid-allylpolyethoxy carboxylate (AA-APEY or AY) was prepared by copolymerization of allylpolyethoxy carboxylate and acrylic acid at different mole ratios. The effect of different AA-to-APEY mole ratios on controlling calcium deposits was studied, and their performance was compared with current commercial inhibitors. It was shown that AY exhibited excellent ability to control inorganic minerals, with approximately 100% calcium phosphate inhibition and 80% calcium carbonate inhibition at dosage of 8 and 6 mg/L, respectively. The micromorphology and crystal of calcium particles were characterized by scanning electron microscopy and X-ray diffraction.

Acrylic acid–allylpolyethoxy carboxylate copolymer as an environmentally friendly calcium carbonate and iron(III) scale inhibitor

A novel environmentally friendly type of calcium carbonate and iron(III) scale inhibitor AQn was synthesized. The anti-scale property of the AQn copolymer toward CaCO3 and iron(III) in the artificial cooling water was studied through static scale inhibition tests. The observation shows that both calcium carbonate and iron(III) inhibition increase with increasing the degree of polymerization of AQn from 5 to 15, and the dosage of AQn plays an important role on calcium carbonate and iron(III) inhibition. The effect on formation of CaCO3 was investigated with combination of scanning electronic microscopy, transmission electron microscopy, X-ray powder diffraction analysis, and Fourier-transform infrared spectrometer, respectively. Inhibition mechanism is proposed that the interactions between calcium or iron ions and polyethylene glycol are the fundamental impetus to restrain the formation of the scale in cooling water systems.

Performance of a non-phosphorus antiscalant on inhibition of calcium-sulfate precipitation

The aim of this study is to report on the performance of a novel non-phosphorus antiscalant, acrylic acid (AA)-allylpolyethoxy carboxylate (APEC), being developed for calcium-sulfate scale inhibition in industrial water systems. The performance of AA-APEC on calcium-sulfate scale inhibition was compared with that of the two commercial inhibitors, polyamino polyether methylene phosphonates (PAPEMP) and polyacrylic acid (PAA), containing the same polyethylene glycol segments or carboxyl functional groups as AA-APEC. The study indicated that AA-APEC could act as a highly effective calcium sulfate inhibitor, having strong ability to inhibit the precipitation of calcium sulfate at a dosage of 2 mg L(-1), showing approximately 83.6% inhibition. The results also showed that AA-APEC dosage, the solution pH, inhibiting temperature, concentration of Ca(2+), and SO(4)(2-) all play important roles in inhibiting calcium-sulfate precipitation. The precipitation thermodynamics and kinetics at different temperatures were also discussed. X-ray diffractometer (XRD) and scanning electron microscope (SEM) analysis showed that AA-APEC strongly affected the texture and the morphology of the deposited calcium sulfate. Calcium sulfate has been inhibited through stabilization by adsorption onto crystal growth sites of nascent crystals altering their morphology.

Carboxylate-Ended Poly(ethylene glycol) Macromonomers and their Copolymers as Inhibitors for Calcium Phosphate and Calcium Sulfate

Carboxylate-ended poly(ethylene glycol) macromonomers, namely allylpolyethoxy carboxylate (APEC), were prepared by means of a carboxy methylation technique with the obvious advantage of energy conservation. APEC and acrylic acid (AA) were then used as monomers to obtain AA/APEC copolymers. Fourier-transform infrared spectra and nuclear magnetic resonance were employed to characterize AA/APEC structure. Observations showed that AA/APEC was a much better inhibitor both for calcium phosphate and calcium sulfate compared to the commercial inhibitors, and it was also an effective inhibitor, even at elevated temperature, pH, Ca2+ and Fe2+ concentration or in the presence of biocides.

Inhibition of Ca3(PO4)2, CaCO3, and CaSO4 Precipitation for Industrial Recycling Water

In an attempt to control Ca3(PO4)2, CaCO3, and CaSO4 deposits in industrial recycling water systems, an acrylic acid (AA)–allylpolyethoxy carboxylate (APEC) copolymer was examined as a nonphosphorus inhibitor. The synthesized AA–APEC copolymer was characterized by FT-IR. The performance of AA–APEC on inhibition of Ca3(PO4)2, CaCO3, and CaSO4 precipitation was compared with that of current commercial inhibitors. It was shown that AA–APEC exhibited excellent ability to control inorganic minerals, with approximately 82.88% CaSO4 inhibition and 99.89% Ca3(PO4)2 inhibition at levels of 3 and 6 mg/L AA–APEC, respectively. AA–APEC also displayed ability to prevent the formation of CaCO3 scales. Transmission electron microscopy (TEM) images indicated that the outstanding performance of AA–APEC on Ca3(PO4)2 inhibition resulted from a decrease in size of Ca3(PO4)2 solid particles thereby dispersing these particles throughout a fluid, while CaCO3 inhibition was attributed to the formation of ribbon-shaped structures...

Novel Non-Phosphorous Antiscalants for Inhibition of Calcium Phosphate and Calcium Sulfate Precipitation

A copolymer of acrylic acid (AA)/allylpolyethoxy carboxylate (APEC) was synthesized, characterized and examined as a non-phosphorous antiscalant for industrial cooling-water. Its ability to prevent calcium phosphate and sulfate precipitation was compared with inhibitory power of acrylic acid (AA)/allylpolyethoxy sulfate (APES) and polyamino polyether methylenephosphonate (PAPEMP). Results indicate that the presence of these antiscalants does reduce the extend of calcium phosphate and sulfate precepitation and AA/APEC exhibits the best performance with 99.59% calcium-phosphate inhibition when the dosage of AA/APEC was 6 mg/L and 82.88% calcium-sulfate inhibition at the dosage of 3 mg/L AA/APEC. AA/APEC has also been proven to be an effective inhibitor for calcium phosphate and calcium sulfate even at elevated solution temperature, pH and Ca2+concentration.

Double-Hydrophilic Block Copolymers as Precipitation Inhibitors for Calcium Phosphate and Iron(III)

Novel double-hydrophilic block copolymers, maleic anhydride (MA)−allylpolyethoxy carboxylate (APEC) and maleic anhydride (MA)−ammonium allylpolyethoxy sulfate (APES), were specially designed and synthesized from allyloxy polyethoxy ether (APEO) to inhibit the precipitation of calcium phosphate and iron (III). Structures of APEO, APEC, MA−APEC, APES, and MA−APES were characterized by FT-IR. The study shows that both MA−APEC and MA−APES have significant ability to inhibit the precipitation of calcium phosphate at the dosage of 6 mg/L, approximately showing 99 and 90% inhibition, respectively. The data of the light transmittance of ferrous solutions show that, compared to MA−APES, MA−APEC has superior ability to stabilize iron (III) in solutions. The light transmittance of ferrous solutions is about 23% in the presence of MA−APEC when the dosage is 6 mg/L, whereas in the presence of MA−APES, it is about 31% at a dosage of 12 mg/L. Scanning electron microscopy (SEM) shows that the copolymers influence the morphology of calcium phosphate crystallites. Transmission electron microscopy (TEM) indicates the excellent inhibition results from the formation of core−shell structure. Double-hydrophilic block copolymers of MA−APEC and MA−APES have also been proven to be effective inhibitors of calcium phosphate and iron (III) even at elevated solution temperature, pH, and Ca2+ and Fe2+ concentration.