Acrylic Acid Sodium Research Articles

Preparation of aqueous Ag Ink with long-term dispersion stability and its inkjet printing for fabricating conductive tracks on a polyimide film

We synthesized silver nanoparticles via chemical reduction method in aqueous medium and poly(acrylic acid) sodium salt (PAA), a kind of anionic polyelectrolyte, was used as a capping agent as well as a dispersant. Owing to the electrosteric repulsion characteristic of PAA, the prepared aqueous Ag ink exhibited a remarkable dispersion stability, which was confirmed by sedimentation test, zeta-potential measurement, and rheological analysis. We fabricated narrow conductive features onto the polyimide substrate using ink-jet printing method and demonstrated the influence of substrate temperature on the morphology of printed patterns. After annealing at 250 °C, the resistivity of the Ag pattern with a linewidth of 60 μm was 4 μΩ cm.

Tuning the electrocatalytic activity of Pt nanoparticles on carbon nanotubes via surface functionalization

Polyelectrolytes with various characteristic functional groups as interlinkers to anchor Pt nanoparticles were used to functionalize carbon nanotubes (CNTs) as Pt electrocatalyst support. It was found that polyanions (poly(styrenesulfonic acid) (PSS), and poly(acrylic acid sodium) (PAA)) have a beneficial effect on methanol electrooxidation on Pt nanoparticles supported on carbon nanotubes via modifying their electronic structure through charge transfer from polyanions to Pt sites and supply of oxygen-containing species. The increased electron density around Pt sites by the charge transfer from polyanions would cause partial filling of Pt 5 d-bands, resulting in the downshift of d-band center and weaker chemisorption with oxygen-containing species (e.g. CO ad). The weakened chemisorption of CO on Pt nanoparticles would promote the methanol electrooxidation. On the contrary, polycations would have an opposite effect on the electronic structure and chemisorption properties of Pt nanoparticles.

Use of Acrylic Acid Sodium Acrylate Polymer to Maintain Cocoa Seed Viability

The main problem of cocoa seed storage is moisture content of the seeds because cocoa seeds will germinate if cocoa seeds moisture content is high. The objective of this research is to maintain the cocoa seeds viability in storage using acrylic acid sodium acrylate polymer (AASAP). The function of AASAP is to absorb humidity in storage due to their ability to retain water and to prevent water loss. The experiment was conducted in a laboratory of Indonesian Coffee and Cocoa Research Institute and in Kaliwining Experimental Garden. This experiment was arranged by factorial randomized complete design, in wich AASAP dosages 0%; 0.1% (0.1 g/100 seeds); 0.2% (0.2 g/100 seeds), 0.3% (0.3 g/100 seeds), 0,4% (0,4g/100 seeds), combined with seeds storage period 1, 2, 3 and 4 weeks. The experiment used 3 replications and each repli cation used 100 seeds. Parameter of observation consisted of percentage of seeds germinated in storage, percentage of seeds infected by fungi in storage, seeds moisture content, percentage of seeds germination after storage, and early growth of cocoa seedlings. The results of the experiment showed that AASAP application with some dosages cocoa seeds storage cause to germinate in storage during 2 weeks. AASAP application with some dosages in cocoa seeds storage for 2 weeks would not result in infection by fungi and did not significantly affect seed germination after storage for 1, 2 and 4 weeks, and percentage of germination of cocoa seed after storage for 3 weeks decreased with increase dosage of AASAP. Higher dosage of AASAP would reduce early growth of cocoa seedling. Key words : Theobroma cacao, seed, acrylic acid sodium acrylate, seed storage, viabilty.

Preparation, characterization, structure, and dynamics of carboxymethyl chitosan grafted with acrylic acid sodium salt

AbstractGraft copolymerization of different vinyl monomers onto chitosan (Cs) and its derivatives can alter their properties and consequently expands their potential applications. In this study, carboxymethyl chitosan (CMCs) was prepared and characterized. Graft copolymerization of acrylic acid sodium salt (AAs) onto CMCs was accomplished by using ammonium persulphate (APS)‐induced free radical polymerization in aqueous medium under nitrogen atmosphere. Occurrence of grafting was confirmed and the effects of [AAs], [APS], reaction time, and temperature on the extent of grafting were studied. The influence of grafting yield on the structure and dynamics was also investigated by using differential scanning calorimetry (DSC), two‐dimensional wide‐angle X‐ray scattering (2D‐WAXS), scanning electron microscopy (SEM), and dielectric spectroscopy. Preliminary study, using dielectric spectroscopy, was carried out to the CMCs‐g‐AAs copolymer with grafting percent ∼ 2900%, as an example, in a wide range of temperature (from 299 to 473 K) and frequency (from 1 × 10−2 to 1 × 105 Hz). One relaxation process with Arrhenius type was detected. This process has the characteristics of a secondary relaxation process related to local chain dynamics with activation energy of 53 ± 3 kJ/mol. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Preparation of Enzymatically Recyclable Hydrogels Through the Formation of Inclusion Complexes of Amylose in a Vine‐Twining Polymerization

In this paper, we describe the preparation of hydrogels through the formation of an inclusion complex of amylose in a vine-twining polymerization. This is achieved by the phosphorylase-catalyzed polymerization of alpha-D-glucose 1-phosphate from maltoheptaose primer, in the presence of a water-soluble copolymer having hydrophobic graft-chains (poly(acrylic acid sodium salt-graft-delta-valerolactone)). The mixture turns into a gel during the polymerization process. Evaluation of the hydrogels is conducted by shear-viscosity measurements of the products. For the hydrogels with relatively high viscosities, fast relaxation modes of the cooperative diffusions are observed by scanning microscopic light scattering measurements, which indicate the nanometer-size network structures of the hydrogels. In addition, we found that the enzymatic disruption and reproduction of the hydrogels are achieved by the combination of the amylase-catalyzed hydrolysis of the amylose component and the formation of amylose by the phosphorylase-catalyzed polymerization.

Synthesis and application of two light-sensitive copolymers forming recyclable aqueous two-phase systems

Recycling aqueous two-phase systems (ATPS) are hopeful application techniques in bioseparation and biocatalysis engineering areas. In this study, two novel light-sensitive and reversible water-soluble copolymers were synthesized and used in recycling ATPS. Polymer P NBAC was polymerized by using N-isopropylacrylamide (NIPA), n-butylmethacrylate (BMA), acrylic acid (AA) and chlorophyllin sodium copper salt (CHL) as monomers. Copolymer P NDBC was synthesized by NIPA, 2-(dimethylamino) ethylmethacrylate (DMAEMA), BMA and CHL as monomers. The synthesis yields of two copolymers are 66.9% and 77.2%, respectively. It can be calculated from 1H NMR graph that the molar ratios of monomers in P NBAC (NIPA:BMA:AA:CHL) and P NDBC (NIPA:DMAEMA:BMA:CHL) was 82:4:1:10 and 16:4:3:1, respectively. They could be precipitated by laser irradiation in 488 nm with the least light density of 1.70 × 10 5 W/m 2. The precipitate energy is 1.79 kJ and 3.52 kJ/g, respectively. Five batches of average recoveries of two copolymers in the ATPS are 96.6% and 97.4%. BSA and l-phenylalanine were partitioned in the novel P NDBC–P NBAC ATPS, and their partition coefficients were 2.1 and 0.52. By applying this ATPS to partition of penicillin, the best partition coefficient K is 4.25.

Alternative polymer precipitants for protein crystallization

A set of 16 inexpensive and commercially available polymer precipitants were tested for protein crystallization. Eight of them were found suitable: polyethylene glycol dimethyl ether of molecular weight (MW) 500, 1000 and 2000; di[poly(ethylene glycol)] adipate, MW 900; poly(ethylene glycol-ran-propylene glycol), MW 2500 and 12000; poly(acrylic acid) sodium salt, MW 2100; and polyethylene glycol methyl ether methacrylate, MW 1100. Two new crystallization screens, PolyA and PolyB, were formulated using these eight polymers, each containing 96 solutions – four polymers in combination with 24 common salts and buffers, covering pH values from 4.5 to 9.0. The screens were tested on 29 proteins, 21 of which were crystallized. The tests confirmed the applicability of the eight polymers as precipitants for protein crystallization.

Gold Nanoparticle-Containing Membranes from in Situ Reduction of a Gold(III)−Aminoethylimidazolium Aurate Salt

The first example of polycarbonate membranes (PC) modified using layer-by-layer (LBL) adsorption of a polyelectrolyte (PE)/AuNPs system [PE = poly(ethylenimine), PEI; poly(acrylic acid) sodium salt, PAA] in which the AuNPs formation occurs via the in situ postdeposition reduction of the incorporated novel gold(III)−aminoethylimidazolium aurate salt [Cl3AuNH2(CH2)2ImMe)][AuCl4] (1) is reported. The reduction of 1 to give gold nanoparticles stabilized by an amino-functionalized ionic liquid (ILNH2-AuNPs), was carried out either by the PAA itself during the LBL deposition or by the combined action of PAA and ascorbic acid, the latter added at the end of the deposition process. The different membranes were characterized with AFM, SEM, TEM, UV−vis, and XRD. The XRD analysis revealed that the presence of ILNH2 caused a remarkable increase of gold nanoparticles with (111) planes parallel to the PC film. The catalytic activity of the modified membranes in the reduction of 4-nitrophenol to 4-aminophenol by NaBH4 was investigated and found higher than membranes modified with preformed citrate-stabilized gold nanoparticles (citr-AuNPs) solutions.

Poly(vinyl phosphonic acid): Hydrodynamic Properties and SEC‐Calibration in Aqueous Solution

Poly(vinyl phosphonic acid) (PVPA) as obtained by free radical polymerization of aqueous vinyl phosphonic acid was studied by light scattering (SLS, DLS) and size exclusion chromatography (SEC) in dilute aqueous solutions containing sufficient salt in order to screen long range electrostatic interactions. Samples of 37<$\overline M _{\rm w}$< 110 × 10(3) were studied. The polymers showed positive A(2) -values in aqueous NaH(2) PO(4) solution (0.04 M), and self-diffusion behavior and R(H) /R(G) -ratios indicative of the structure of random coiled chains. A comparison of the SEC-elugrams of the PVPA-samples with those of commercially available standards of poly(acrylic acid) sodium salt gave a fit to the same calibration curve described by log P(n(PVPA)) = -0.21ν(e) + 7.0(+0.1) which correlates the number average degree of polymerization (P(n) ) with the elution volume ν(e) . This indicates that PVPA and PAA have the same hydrodynamic structure under given solution conditions.

Polymer-Induced Liquid-Precursor (PILP) Process in the Non-Calcium Based Systems of Barium and Strontium Carbonate

Barium and strontium carbonate with various nonequilibrium morphologies were grown in the presence of poly(acrylic acid) sodium salt to induce the polymer-induced liquid-precursor (PILP) process. Previously, the PILP process had only been demonstrated for calcium carbonate but with indirect evidence suggesting it can be induced in calcium phosphate and barium carbonate. In this report, further evidence to suggest a similar liquid-phase amorphous precursor can be generated for both barium and strontium carbonate is presented, and these phases were used to synthesize various unique morphologies in the transformed crystals, including films, fibers, and cones. On the basis of the nanogranular texture of the fibers, a new mechanism for fiber formation is proposed, which combines a permutation of our former solution−precursor−solid (SPS) mechanism with mesocrystal assembly. This hypothesis includes an autocatalytic assembly of nanodroplets/nanoparticles at high energy surface protrusions as a means for generati...

The effect of chelating agents on synthesised nano-sized CoAl&lt;SUB align=right&gt;2O&lt;SUB align=right&gt;4 by thermal decomposition

Nano-sized CoAl2O4 spinel powders were synthesised by thermal decomposition with different chelating agents and surfactants [urea (U), citric acid (CA), sucrose (S), starch (St), poly (acrylic acid sodium salt) (PAS)]. Characterisation of result CoAl2O4 nanoparticles were performed by using X-ray diffractometer (XRD), scanning electron microscopy (SEM), energy disperse X-ray analysis (EDX), UV-Visible and FT-IR spectroscopy. The range size of result nanoparticles is 20-40 nm.

Anionic polyacrylamide “water-in-water” emulsion prepared by dispersion polymerization in mixed salt aqueous media

AbstractPolyacrylamide “water-in-water” emulsion was regarded as a new generation of water-soluble polymeric materials and has attracted much attention from both academia and industry because of its environmentally-friendly character. Anionic polymeric “water-in-water” emulsions prepared by dispersion polymerization of acrylamide (AM) and sodium acrylic acid (NaAA) in mixed solution of Na2SO4 and (NH4)2SO4 are reported in this paper, and the parameters influencing polymerization and the final dispersion stability, including, N2 flow rate, chain transfer agent content, inorganic salt content, and the molar ratio of AM to NaAA were examined and opitimized. It was found that the intrinsic viscosity of resulting copolymers decreased as the N2 flow rate and CTA concentration increased, and the resultant dispersions with 27 % ∼ 28 % inorganic salt have regular particle shape, lowest particle size, better flowability and storage stability. The salt level in the reaction system would also dominate the time that the dispersion formed, and the ratio of AM to NaAA would influence the total monomers conversion and polymerization rate.

Synthesis and characterization of pH‐ and salt‐responsive hydrogels based on etherificated sodium alginate

AbstractHydrogels composed of etherificated sodium alginate (ESA), sodium acrylic acid (NaAA), and poly (vinyl alcohol) (PVA) were synthesized by aqueous solution polymerization. The effects of reaction variables such as terminal pH, ions, and ionic strength on hydrogel swelling ratio (SR) were determined and compared. SR was influenced strongly by pH and ionic strength. SR increased with increasing pH but tended to decrease with PVA content. At a given ionic strength, SR of ESA/NaAA/PVA hydrogel was dependent on the valence of anion; SR was higher in multivalent anion salt solution than in monovalent anion salt solution, i.e., SRK2SO4 &gt; SRKCl and SRNa2SO4 &gt; SRNaCl. The swelling kinetic of the hydrogels showed Fickian kinetic diffusion in acidic media and non‐Fickian behavior in alkaline media. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Treatment of copper (II)-loaded aqueous nitrate solutions by polymer enhanced ultrafiltration and electrodeposition

In this investigation the main design parameters of a process for the recovery of copper (II) ions from synthetic aqueous solutions have been obtained. The proposed process comprises the following stages: metal ion retention, polymer regeneration and metal recovery. Metal ion retention was performed by a batch polymer enhanced ultrafiltration (PEUF) process. For this, a bench-scale plant configured in closed-loop has been used. Selected water-soluble polymer was an industrial grade antiscalant called Colloid 208® (poly(acrylic acid) sodium salt, Mw 50,000 g mol−1). This polymer is responsible to sequester metal ion and to form macromolecular metallic complexes that can be rejected by an UF ceramic membrane (Carbosep M5; 10,000 Da). Temporal decrease of permeate fluxes has been reproduced with an empirical fouling model and evolution of metal rejection coefficients was estimated with a model taking into account chemical equilibriums in solution and mass conservation equations. Polymer regeneration and metal recovery stages have been tackled by both chemical (diafiltration) and electrochemical (electrodeposition) points of view. Electrodeposition showed more advantages, namely null water consumption, recovery of copper in its most valuable form and absence of regeneration solutions to be treated or reused. Moreover, it has been checked that polymer did not suffer oxidation or reduction reactions because of the electrochemical stage.

Antimicrobial Colloidal Suspensions of Silver-Titania

Titanium dioxide nanoparticles (TiO2Np) exhibiting properties of photocatalyst under ultraviolet light (UV) exposition related with destruction of some hazardous organic moieties. To enhance the antibacterial characteristics of this material in our works, we developed a new of TiO2Np doping with silver nanoparticles (Ag 0 Np), whose biocidal properties are well defined. The obtained products, Ag 0 Np/TiO2Np, in the form of suspensions and powders were characterized from chemical, physical and antimicrobial activity point of view. In addition, a mechanism of Ag + ions reduction reaction to Ag 0 Np has been proposed. The developed of the Ag 0 Np/TiO2Np synthesis consists of the in situ chemical deposition of the Ag 0 Np on the dispersed TiO2Np in the form of anatase, using aqueous solutions of poly(acrylic acid sodium salt) (PAS) and NaBH4. The Ag 0 Np synthesis was carried out both in the presence and absence of TiO2Np. The chemical composition of Ag 0 Np/TiO2Np was assessed by atomic absorption spectrometrical (AAS). The physical properties were evaluated as follows: crystallite structure and dimensions of nanopowders by X-ray diffraction (XRD), UV-Vis absorption of colloidal suspensions and UV-Vis reflectance of nanopowders by spectrophotometrical method, grain size distribution of nanoparticles by dynamic light scattering (DLS), stability of colloidal suspensions by zeta potential measurements, forms and shapes of Ag 0 Np and Ag 0 Np/TiO2Np by transmission electronic microscopy (TEM) and scanning electronic microscopy (SEM) respectively. The antimicrobial activity was tested by standard methods against some broad spectra of fungi and bacteria. In suspensions, the concentration of TiO2Np was 1 wt. % and the concentration of Ag 0 Np varied in the range of 0.005…0.15 wt. %. The Ag 0 Np suspensions and Ag 0 Np/TiO2Np suspensions were stable from the physical and chemical point of view. The physical characterization test results were in accordance, proving the achievement of colloidal solutions containing Ag 0 Np and TiO2Np spherical nanocrystallite with average diameters of 4.1 nm and 7.8 nm, respectively. The results of the biological tests showed the high fungistatic and antibacterial activities of both products in form of colloidal suspensions and powders. The developed one pot method is efficient, ecological and easy to be scaled-up. The obtained products have biological activity but it depends on the nature of the tested germs, lowering in the series: Gram negative bacteria, Gram positive bacteria and fungi. Also, a synergistic action was proved at destroying of Trichoderma viride fungus, which was not obtained either for Ag 0 Np or for TiO2Np, independently.

Grafting Study and Antifungal Activity of a Carboxymethyl Cellulose Derivative

Graft copolymerization of appropriate monomers onto cellulose and its derivatives can enhance their characteristics and consequently expand their potential applications. Carboxymethyl cellulose (CMC) was prepared and characterized by FTIR spectroscopy and XRD. Graft copolymerization of acrylic acid sodium salt (AAs) onto CMC using ammonium persulfate (APS) as a free radical initiator was carried out under nitrogen atmosphere in aqueous solution. Occurrence of grafting was confirmed by comparison of FTIR spectra of CMC and the graft copolymers as well as the XRD patterns and thermal analysis. The effects of concentration of AA, temperature, concentration of APS and reaction time on the grafting yield were investigated by determining the grafting percentage and grafting efficiency. With other conditions kept constant, the obtained optimum grafting conditions were: CMC = 0.2 g, [AAs] = 2 mM, [APS] = 7.5 mM, temperature = 70°C and reaction time = 2 h. A preliminary study was then carried out to evaluate the antifungal activity of the prepared graft copolymer. This preliminary investigation of the prepared graft copolymers showed that they may be tailored and exploited to expand the utilization of these systems in medical applications.

Selective separation of Hg(II) and Cd(II) from aqueous solutions by complexation–ultrafiltration process

Complexation–ultrafiltration process was investigated to separate selectively Hg(II) and Cd(II) from binary metal solutions by using poly (acrylic acid) sodium salt as a complexing agent. Effects of operating parameters on selective separation factors ( β Cd/Hg) of the both metals have been examined in detail. Results indicated that loading rate, pH, concentration of salt added and low-molecular competitive complexing agent affect significantly β Cd/Hg value. Further, a concentration experiment was carried out according to the previous optimum parameters. Rejection coefficient of mercury is close to 1, while that of cadmium is about 0.1. The experiment was characterized by good effectiveness, and enabled the rapid linear increase of mercury concentration and very slow increase of cadmium concentration in the retentate. Then, a diafiltration technique was applied to separate further the both metals. Cadmium concentration in the retentate declines sharply with the diafiltration volume, whereas for mercury it is the contrary.

Preparation of polyacrylamide aqueous dispersions using poly(sodium acrylic acid) as stabilizer

AbstractHigh‐solids, low‐viscosity, stable polyacrylamide (PAM) aqueous dispersions were prepared by dispersion polymerization of acrylamide in aqueous solution of ammonium sulfate (AS) using poly (sodium acrylic acid) (PAANa) as the stabilizer, ammonium persulfate (APS) or 2,2′‐Azobis (N,N′‐dimethyleneisobutyramidine) dihydrochloride (VA‐044) as the initiator. The molecular weight of the formed PAM, ranged from 710, 000 g/mol to 4,330,000 g/mol, was controlled by the addition of sodium formate as a conventional chain‐transfer agent. The progress of a typical AM dispersion polymerization was monitored with aqueous size exclusion chromatography. The influences of the AS concentration, the poly(sodium acrylic acid) concentration, the initiator type and concentration, the chain‐transfer agent concentration and temperature on the monomer conversion, the dispersion viscosity, the PAM molecular weight and distribution, the particle size and morphology were systematically investigated. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Preparation of Poly(vinylidene fluoride-co-trifluoroethylene) Film with a Hydrophilic Surface by Direct Surface-initiated Atom Transfer Radical Polymerization without Pretreatment

Abstract Surface-initiated atom transfer radical polymerization (ATRP) of tert-butyl acrylate was carried out directly from a nonmodified poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-co-TrFE)] film surface to give a polymer brush, which was further converted to a poly(acrylic acid sodium salt) brush by hydrolysis. A hydrophilic surface was successfully created at the outermost surface of P(VDF-co-TrFE) film without any change in the bulk physical properties. Also the effect of surface nanotexture formation on wettability was investigated.

Synthesis and properties of new amphoteric poly(amidoamine) dendrimers

A series of new amphoteric dendrimers have been synthesized by attaching dimethylbenzylaminoethyl acrylate chloride (Bz80), sodium acrylic acid (SAA) and modified polyoxyethylene (MPEO) units to a third-generation poly(ami- doamine) (PAMAM) dendrimer core via Michael addition reaction. The structure of the dendrimers was confirmed by Fourier transform infrared (FTIR), proton nuclear magnetic resonance (1H NMR), carbon 13 nuclear magnetic resonance ( 13 C NMR) spectroscopy and by elemental analysis. Thermal stability and intrinsic viscosity were investigated. The appli- cable experiment exhibited the amphoteric dendrimers have high flocculation efficiency, which could be significantly improved by combining amphoteric dendrimers with polyacrylamide (PAM). The suitable mass ratio of the dendrimers and PAM was 2:3. The study would promote the use of amphoteric dendrimers as a flocculant in treating wastewater and as a new paper retention aid in papermaking.