Ratio Of Acrylic Acid Research Articles

Effect of Poly(Acrylic Acid) Based Polymer Flocculants on Sedimentation of Surface Water

In most scenarios, there tend to have some impurities such as organic and inorganic substances found on the surface water. These impurities can be classified as insoluble and soluble compounds which in turn, can be purified by filtration and sedimentation prior used. Calcium carbonate (CaCO3), is one of the most contaminated compounds on surface water, mainly causes severe damage to industrial parts. Therefore, CaCO3 need immediate removal from raw water before applied to an unit operation by coagulation and flocculation. We mainly focused on precipitation of synthetic water and raw water with polyaluminium chloride (PAC) and synthetic polymer flocculants in this research study. The synthetic flocculants of Polyacrylic acid (PAA), Polyacrylamide (PAM) and Poly (acrylic acid-co-acrylamide) (PAAAM) by free radical polymerization in aqueous. The PAAAM is synthesized in various mole ratio of acrylic acid and acrylamide of 9:1 to 5:5. The polymer flocculants are characterized by FT-IR and 1H-NMR techniques. The FTIR spectra of the sample showed absorption frequency above HYPERLINK "tel:3200-3000" \t "_blank" 3200-3000, 1750-1550 and 1650-1500 corresponding to OH and CO stretching and NH bending respectively. The 1H-NMR spectra of PAM showed chemical shift at 1.50, 2.10 and 4.20 ppm regarding to proton of methyl, methylene and amide group respectively and the present of proton resonances at 1.50 and 2.30 ppm regarding to proton of methyl and methylene of PAA. The removal efficiency of suspended CaCO3 is measured and calculated via turbidity technique. The dosage of PAC 0.1 ppm can remove suspended CaCO3 approximately 65.33% after the PAAAM with mole ratio of 8:2 is applied to system lead to the removal efficiency increasing to 99.03%.

Effect of acrylic acid on the mechanical properties of PVA/ starch blend films

Grafting polymers based on acrylic acid (AA) with blend copolymer were synthesized with different ratio of AA (0.125, 0.25 and 0.5% by mass of blend copolymer) using ammonium persulfate as an initiator. The blend copolymer (PVA/S) was prepared by blending poly(vinyl alcohol) (PVA) with starch (S) in ratio (1: 1 wt.%), in presence of glacial acetic acid as a catalyst. The obtained polymers (PVA/S/AA) were characterized by FT-IR, TGA, DTG, SEM and mechanical test. The results showed that the mechanical properties of blend films are strongly dependent on the AA. Moreover, an increase in the ratio of AA in grafted polymers, increase thermal stability, tensile strength and elongation at break.

Synthesis and Water Absorbing Properties of KGM-g-P(AA-AM-(DMAEA-EB)) via Grafting Polymerization Method

In this study, a novel KGM-based superabsorbent polymer KGM-g-poly-(acrylic acid-co-acrylamide-co-N,N'-dimethyl-N-ethylmethacryloxylethylammoniumbromide) (KAAD) was prepared, which was obtained by the free radical grafting solution polymerization of acrylamide (AM), acrylic acid (AA) and N,N'-dimethyl-N-ethylethacryloxylethylammonium bromide (DMAEA-EB) onto konjac glucomannan (KGM) with of potassium persulfate (K2S2O8) as initiator and N,N'-methylenebisacrylamide (MBA) as crosslinker. The groups of AA, AM and DMAEA-EB grafted on KGM were detected by infrared spectroscopy (FTIR). The effects of the reaction conditions (including an initiator dosage, AA and AM mass ratio, and a reaction temperature, etc.) on the grafting degree and grafting efficiency were investigated by a gravimetric method. The maximum grafting degree and grafting efficiency of the obtained graft polymer in the experiment were 71.51 and 89.90%, respectively. The effects of crosslinking agent and GD on water absorption were explored. And all of the experimental data show that the water absorption ratio of the KAAD resin exceeds 527.00 g/g under each optimal reaction conditions. Therefore, KAAD can be widely used as a functional material in pharmaceutics, textiles, construction and other fields due to its excellent superabsorbent properties.

Influence of Monomer Ratios on Molecular Weight Properties and Dispersing Effectiveness in Polycarboxylate Superplasticizers.

A series of polycarboxylate superplasticizer (PCE) polymers were synthesized from acrylic acid (AA) and isoprenyloxy polyethylene glycol ether (IPEG) at the mole ratios of 3.0, 4.2, 5.0 and 6.0. In this study, the molecular weight properties of PCE polymers were recorded by size exclusion chromatography with the time interval of 1 h. Mini slump test was used to detect the dispersing effectiveness of PCE polymer in cement paste. The results indicated that the reaction rate of monomers, conversion of 52IPEG macromonomer and molecular weight of PCE polymers increased with the general adding ratio of AA to IPEG macromonomers while the side chain density of PCE polymers decreased. PCE polymers possessed molecular weight around 30,000 g/mol with low side chain density, and long main chain length presented high initial dispersing effectiveness at the low dosage around 0.12%. The majority of effective PCE polymers were formed during the adding period of acrylic acid in the first 3 h.

A Modified Preparation of Cellulosic‐Absorbent Resin for Cu2+ Removal under Microwave Irradiation

The absorbent resin for Cu2+ removal was prepared under microwave irradiation through grafting acrylamide (AM) and acrylic acid (AA) to cellulose. The initiator is a kind of redox system composed of potassium persulfate/sodium thiosulfate. The crosslinking agent is N,N′‐methylene bisacrylamide. The optimal reaction conditions are as follows: the ratio of AA to cellulose is 10 : 1, initiator to AA is 0.65 wt%, crosslinking agent to AA is 1.0 wt%, neutralization degree of AA is 75%, microwave power level is 320 W, and time is 300 s. The maximum absorption capability of the resin is 65 mg·g−1. Different from previous studies, the reaction was carried out without the protection of nitrogen and troublesome posttreatment. The product was obtained directly by one‐step synthesis without purification and drying of the crude product. The pollution and cost caused by organic solvent are avoided, and the whole preparation period is shortened deeply. Moreover, the time of absorption equilibrium is shorter. In a word, the preparation in this paper has the obvious advantages, such as simple process, short time, no pollution, low‐energy, and low‐cost.

Synthesis and adsorption properties of acrylic acid/styrene binary copolymer resin

In order to improve the adsorption of heavy metals in polyacrylic hydrogels, the experiment uses acrylic acid and styrene as raw materials, potassium per sulfate as initiator, and ethylene glycol as crosslinker to synthesize polyacrylic acid/styrene hydrogel. The effects of monomer ratio, acrylic acid neutralization degree, crosslinker dosage and temperature on product properties were studied by orthogonal test. In addition, the copolymer was characterized by fourier transform infrared spectroscopy. The adsorption of heavy metal performance test found that when the ratio of acrylic acid and styrene is 1:0.2, the degree of neutralization is 65%, the crosslinker accounts for 1.0% of the monomer mass fraction, and the temperature is 65 °C, the polyacrylic acid/styrene copolymer hydrogel is optimal. The adsorption of Pb2 + in the optimal group was 328.25 mg/g.

Facile droplet microfluidics preparation of larger PAM-based particles and investigation of their swelling gelation behavior

AbstractIn this paper, a millimeter-sized temporary plugging agent particles based on polyacrylamide were synthesized by combining microfluidics technology with consolidation mechanism of suspension polymerization, which using W/O emulsion template and with droplet as micro-reaction vessel. The effect of various variables on the gel particle properties was studied so as to determine the best proportion and optimize the preparation process. Fourier transform infrared (FTIR) spectroscopy, Digital imaging and SEM were used to characterize the composition and morphology of the PAM gel particle. The results indicated that the obtained PAM gel particle has regular shape and good transparency. And it is concluded that when the molar ratio of acrylic acid (AA) and acrylamie (AM) monomers is 5:5, w(K2S2O8) = 0.8%, w(Al(NO3)3) = 1.0%, neutralization degree was 60%, the prepared PAM gel particles has the best performance. The preparation process is simple while the cost is low, so it could be used as a promising temporary plugging agent in future.

Preparation for polyacrylic acid modified by ester group in side chain and its application as viscosity enhancing agent in polycarboxylate superplasticizer system

The problem of bleeding and segregation in high fluidity concrete can be eliminated by the addition of viscosity-enhancing agents (VEA). However, the dispersion capacity of PCE would be perturbed by the addition of VEA. In most cases, this negative impact was due to competitive adsorption between VEA and PCE. In order to mitigate the negative impact, ester groups were introduced to reduce the adsorption capacity, and one new kind of viscosity-enhancing agents was designed; the polymers were copolymerized of acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA), with 1:1 and 1:8 M ratios of AA and HEA. And then, the effect of these two VEAs on rheology of cement paste plasticized by PCE at 5 min and 30 min were studied. Adsorption behavior was analyzed by total organic carbon (TOC), and the zeta potential was also measured. The conformation of the polymers in liquid phase were analyzed by dynamic light scattering (DLS). And the decomposition of ester group under alkaline condition was verified by FTIR and 1HNMR. The results indicated that the synthesized VEA could plasticize cement paste, and the reason was that VEA could be adsorbed by cement grains and act as the same role as the first-generation superplasticizer. The plasticizing capacity was increased over time, because the adsorption capacity was enhanced due to the released carboxyl groups from the decomposition of ester groups. Furthermore, from 5 min to 30 min, the decomposition of ester group could increase the conformation size of VEA by producing crosslinking in the presence of Ca2+, and the crosslinking act as positive role in increasing viscosity and resist the bleeding and segregation. Moreover, it was observed that VEA had negative impact on dispersion capacity of PCE, and the higher density of ester group resulted in lower negative impact at the beginning; one reason for this was because the higher density of ester group showed lower competitive adsorption capacity. Such results offered one new type of VEA available for superplasticizer system.

Preparation of Superabsorbent Polymer from Sugarcane Bagasse via Extrusion Process

The aim of this research study is to develop a biodegradable superabsorbent polymer, based on cellulose from sugarcane bagasse (SCB), for water resource management, horticulture, and other products in agricultural applications. A SCB superabsorbent polymer was polymerized from SCB and acrylic acid (AA) monomer in the presence of N, N-methylene-bisacrylamide as a cross-linker by using corotating twin-screw extruder. The ratios of SCB and AA were varied in order to enhance the swelling ability of the absorbent polymer. Polymerization of SCB superabsorbent polymer was initiated by using ammonium persulfate as an initiator in a normal system and ammonium persulfate/sodium sulfite as a couple initiator in redox system. The results indicated that the swelling ability of superabsorbent polymer prepared by ammonium persulfate/sodium sulfite as a couple initiator was higher than that of the polymer prepared by ammonium persulfate as the initiator. The SCB superabsorbent polymer prepared under optimized polymerization conditions was mixed in soil, and the water-retaining ability of the soil was subsequently investigated. Soil water retention was improved in the presence of the SCB superabsorbent polymer. These results confirmed that the superabsorbent polymer prepared from polymerization of SCB and AA in the presence of N, N-methylene-bisacrylamide as a cross-linker and ammonium persulfate as an initiator by using corotating twin-screw extruder could potentially be used as an agricultural water resource.

Methylene blue removal by using pectin-based hydrogels extracted from dragon fruit peel waste using gamma and microwave radiation polymerization techniques

This research aims to compare the ability of smart hydrogel in removing the methylene blue prepared by using two different radiation methods. The extracted pectin from the dragon fruit peel (Hylocereus polyrhizus) was used with acrylic acid (AA) to produce a polymerized hydrogel through gamma and microwave radiation. The optimum hydrogel swelling capacity was obtained by varying the dose of radiation, pectin to AA ratio and pH used. From the array of samples, the ideal hydrogel was obtained at pH 8 with a ratio of 2:3 (pectin: AA) using 10 kGy and 400 W radiated gamma and microwave respectively. The performance of both hydrogels namely as Pc/AA(G) (gamma) and Pc/AA(Mw) (microwave) were investigated using methylene blue (MB) adsorption studies. In this study, three variables were manipulated, pH and MB concentration and hydrogel mass in order to find the optimum condition for the adsorption. Results showed that 20 mg of Pc/AA(G) performed the highest MB removal which was about 45% of 20 mg/L MB at pH 8. While 30 mg of Pc/AA(Mw) able to remove up to 35% of 20 mg/L MB at the same pH condition. To describe the adsorption mechanism, both kinetic models pseudo-first-order, pseudo-second-order were employed. The results from kinetic data showed that it fitted the pseudo-first-order as compared to pseudo-second-order model equation. This study provides alternative of green, facile and affective biomaterial for dye absorbents that readily available.

Water- and Fertilizer-Integrated Hydrogel Derived from the Polymerization of Acrylic Acid and Urea as a Slow-Release N Fertilizer and Water Retention in Agriculture.

To reduce the preparation cost of superabsorbent and improve the N release rate at the same time, a novel low-cost superabsorbent (SA) with the function of N slow release was prepared by chemical synthesis with neutralized acrylic acid (AA), urea, potassium persulfate (KPS), and N, N'-methylenebis(acrylamide) (MBA). The order of influence factors on the water absorbency property was determined by an orthogonal L18(3)7 experiment. On the basis of the optimization results of the orthogonal experiment, the effects of a single factor on the water absorption were investigated, and the highest water absorbency (909 g/g) was achieved for the conditions of 1.0 mol urea/mol AA ratio, 100% of AA neutralized, K+, 1.5% KPS to AA mass fraction, 0.02% MBA to AA mass fraction, 45 °C reaction temperature, and 4.0 h reaction time. The optimal sample was characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Swelling behaviors of the superabsorbent were investigated in distilled water and various soil and salt solutions. The water-release kinetics of SA in different negative pressures and soils were systematically investigated. Additionally, the maize seed germination in various types of soil with different amounts of SA was proposed, and the N could release 3.71% after being incubated in distilled water for 40 days. After 192 h, the relative water content of SA-treated sandy loam, loam, and paddy soil were 42, 56, and 45%, respectively. All of the results in this work showed that SA had good water retention and slow N-release properties, which are expected to have potential applications in sustainable modern agriculture.

Surface Modification of Linen Fabric via UV Induced Grafting to Improve Dyeability and Wearability

ABSTRACTLinen fabric was surface modified with acrylic acid (AA) and acrylamide (AM) using diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO) as photoinitiator via UV induced grafting to improve dyeing performance and wearability. Effects of different mass ratios of AA and AM in monomer mixture on dyeing performance and wearability were discussed. Maximum dye uptake of 79.4% of cationic dyes was achieved when AA was grafted only and 0/100 of AA and AM could be applied to dye a light color for good color fastness. Dyeing performance of grafted fabric was also improved with reactive dyes and direct dyes. In addition, breaking strength and rigidity of grafted fabric were improved.

Regulating the arm structure of star‐shaped polycarboxylate superplasticizers as a means to enhance cement paste workability

ABSTRACTStar‐shaped superplasticizers, which incorporated polyol ester with unsaturated bond at their cores and bore comb‐type structures as their arms were synthesized via esterification‐copolymerization in aqueous phase from pentaerythritol, acrylic acid (AA), and isopentenyl oxy poly(ethylene glycol ether) (TPEG). The monomer ratios of AA and TPEG were varied and comonomer sodium methallyl sulfonate (SMAS) bearing short side chains was added to regulate the arm structure of star‐shaped polycarboxylate superplasticizers (SPCEs). The effects of the SPCEs on cement paste were investigated and the cement dispersion as well as early hydration mechanism were explored. As a main result, SPCEs with SMAS and certain molar ratios for anchoring groups and PEO side‐chains in their arm structure exhibited good paste dispersion and fluidity retention, which also delayed the early hydration process and prolonged both the initial and the final setting time. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46312.

Synthesis of Hydrophilic Polyelectrolyte as Draw Solute for Forward Osmosis Process

Synthesis and characterization of hydrophilic polyelectrolyte was performed in this work and used as draw solute for forward osmosis (FO) process. The effect of different ratios of acrylic acid (AA) and benzoyl peroxide (B) on the properties of polyelectrolyte was studied in this work. The physical and chemical properties of draw solution (DS) such as pH, conductivity, osmolality, viscosity, molecular weights and functional group were investigated. Results showed that the solution osmolality increased with increasing AA/B ratio. Self-synthesized polyelectrolytes with different molecular weights (MWs) were further correlated with its solution osmolality. The self-synthesized polyelectrolytes of PAA-K and PAA-Na showed an increasing of hydrophilic functional groups such as –OH or COOH. PAA-Na with lower MW and high osmotic pressure in the aqueous solution is found to exhibit a lower reverse solute flux during FO process. Meanwhile for the polyelectrolyte with higher MW, higher viscosity and lower diffusion coefficient were reported.

Morphology and drug release behavior of N-isopropylacrylamide/acrylic acid copolymer as stimuli-responsive nanogels

Thermo- and pH-responsive N-isopropylacrylamide (NIPAM) nanogels can be obtained by copolymerization of acrylic acid (AA) comonomer through differential microemulsion polymerization. The effects of comonomer, cross-linker, surfactant contents, and water/oil ratio were preliminarily investigated by a 24 full factorial design in order to eliminate the insignificant parameters from the polymerization analysis. The smallest poly(NIPAM-co-AA) nanogel particles were 40 ± 1 nm in diameter with 6 wt% of solid content and 98% conversion without coagulation. The comonomer amounts controlled the morphologies and LCST of the poly(NIPAM-co-AA) nanogels. The hairy microgels of poly(NIPAM-co-AA) with a 10:90 mol ratio of AA/ NIPAM had a lower critical solution temperature (LCST) of 6 °C. With an increase in the AA amount to a 17 mol ratio, the LCST increased to 27 °C, resulting in core-shell morphology. The morphology of resultant nanogels was characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, and differential scanning calorimetry. Nuclear magnetic resonance spectroscopy was used to calculate the mole ratio of NIPAM and AA in resultant nanogels after dialysis. Both nanogel mole ratio and morphology effectively retained the cationic anti-cancer drug of methylene blue for several hours, an important basic requirement for a drug delivery system. Compared to core-shell microgels, a higher methylene blue release was obtained from the hairy microgels in simulated intestinal fluid.

Preparation and characterization of a superabsorbent slow‐release fertilizer with sodium alginate and biochar

ABSTRACTA novel hydrogel was synthesized through the graft copolymerization of acrylic acid (AA) and acrylamide (AM) onto sodium alginate with ammonium persulfate as the initiator, methylene bisacrylamide as the crosslinking agent, and calcium chloride as the precipitating agent. Rapeseed meal biochar made at 300 °C was also used. A series of graft copolymers with various molar ratio of AA to AM was prepared. The structures of the hydrogels were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The free absorbency and rate of release were investigated. The grafting efficiency increased as the concentration of AM increased. There was a considerable percentage of nitrogen in the graft copolymers, and the release rate of nitrogen from fertilizer in soil and water decreased with increasing concentration of AM. The water retention of soil without hydrogel remained at 63 and 53.4% on the 10th and 20th days, but with the hydrogels, it was above 70% even on the last day. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45966.

Preparation and Structural Analysis of Nano-Silver Loaded Poly(styrene-co-acrylic acid) Core-Shell Nanospheres with Defined Shape and Composition.

A systematic study for the preparation and structural analysis of poly(styrene-co-acrylic acid) composite nanospheres (PSA) and silver nanoparticles loaded poly(styrene-co-acrylic acid) composite nanospheres (nAg@PSA) is reported. Poly(styrene-co-acrylic acid) nanospheres were synthesized by soap-free emulsion polymerization of styrene (St) and acrylic acid (AA) in water. Ag nanoparticles (Ag-NPs) were well-dispersed on the surfaces of poly(styrene-co-acrylic acid) composite nanospheres by in situ chemical reduction of AgNO3 using NaBH4 as a reducing agent in water. The particle size of PSA nanospheres was uniform. The surfaces of PSA nanospheres were distributed by highly uniform half-sphere arrays. Those half-sphere protruded more with the increase of the feeding amount of AA or the feed ratios of AA and St. The carboxyl groups content of nanospheres was directly proportional to the nanosphere surface area. This relationship and X-ray photoelectron spectroscopy and transmission electron microscopy images of the PSA nanospheres indicate that the acrylic acid was mainly distributed on the surface of the polystyrene spheres with unnegligible thickness. The number of Ag-NPs depends on immobilized carboxyl groups on the surface of PSA, according to thermogravimetry, ultraviolet-visible, X-ray diffraction and transmission electron microscopy results.

Rice Husk Char/Poly-(Acrylic Acid-co-acrylamide) Superabsorbent Hydrogels: Preparation, Characterization, and Swelling Behaviors

A series of novel rice husk char/poly-(acrylic acid(AA)-co-acrylamide(AM)) superabsorbent hydrogels were synthesized by graft copolymerization. The effects of the rice husk char (RHC) loading on their miscibility, shapes, and chemical structures were studied, and their swelling behaviors, kinetics, and pH response were evaluated. During the preparation, RHC reacted with acrylic acid. The RHC at lower loads (< mass ratios of RHC and AA of 1%) was scattered well within the polymer matrix, but an excessive load might result in the formation of large agglomerates. The swelling capacity and swelling rate of the hydrogels first were both increased with the rising RHC loading to 1% and then declined with further RHC loading. The superabsorbent hydrogel containing 1% RHC had the highest water absorbency (869 g/g in deionized water and 97 g/g in 0.9% NaCl solution).

Synthesis and Water Absorbency Properties of Hydrogels Based on Lotus Root Starch

ABSTRACTIn order to increase the added value of lotus root starch, a new-style hydrogel was prepared by grafting copolymerization by acrylic acid (AA), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), K2S2O8, and N,N′- methylene-bis-acrylamide (MBA) in presence of lotus root starch. The molecular structure was characterized by Fourier transform infrared spectroscopy (FTIR). The different conditions that had an influence on the water absorbency are discussed, such as the ratio of initiator to monomers, the ratio of cross-linker to monomers, the mass ratio of AA and AMPS, the lotus root starch's mass, and the reaction temperature. For the product having the optimal water absorbency of 476 g/g, its water absorption kinetics diffusion model and equation were also researched. The material is friendly to the environment and is suggested to have significant potential to be used in various fields.

Synthesis and characterization of superabsorbent hydrogels based on hydroxyethylcellulose and acrylic acid

Hydroxyethylcellulose (HEC)/acrylic acid (AAc) copolymer gels with superabsorbent properties were synthesized from aqueous solutions by radiation-initiated crosslinking. The effect of the acrylic acid content on gel properties was determined at different synthesis conditions. The partial replacement of the cellulose derivative with acrylic acid improved the gelation, leading to higher gel fraction and lower water uptake even in very low concentrations (1–5%). In the presence of acrylic acid lower dose and solute concentration was required for the gel synthesis. The molecular properties of the hydroxyethylcellulose also had a major effect on the gelation: higher molecular mass resulted in better gel properties. The acrylic acid also affected the electrolyte sensitivity of the hydrogels: while pure HEC gels were unaffected by the ionic strength of the solvent, the water uptake of HEC/AAc gels decreased with the salt concentration. The sensitivity also depended on the acrylic acid ratio.