Acrylic Dispersion Research Articles

Treated Textile Electrostatic Properties Study

In the article research results are presented, which aim to provide treated textile electrostatic properties study. In the article research results are presented, which aim to provide find out abilities of an anti-electrostatic treatment and binding agents for it in treatment of special textile materials and their dependance from modes of operating textile washing. Results of determine a composition and abilities of a functional impregnation; develop a method to study values of electrostatic field for tribocharging conditions of textile materialsare; experimental studies of electrostatic values of materials with functional treatment depending on operating washing modes also presented here. Study results allowed to establish efficiency of the proposed combination of anti-electrostatic active composition based on 5 % solution of dialkyldimethylammonium chloride with a binding agent with the effect to preserve the treatment in the material structure and content of which is 4 % in application of textile fabric with widely used fiber content (cotton 53 %, polyester + oil and water-proofing finish). Acrylic dispersion is stable film-forming component suitable in preserving anti-electrostatic treatment on the surface of a textile material. The research was made in Don State Technical University within the framework of State Assignment of the Ministry of education and science of Russia under the project 11.9194.2017/BCh.

Modeling of Ultrafiltration Process Taking Into Account the Formation of Sediment on Membrane Surface

A mathematical model is proposed for separating liquids which contain acrylic dispersions and returning expensive technological components dissolved within them to the production cycle. The main limiting factor is the formation of a sediment layer on the membrane surface. This process is unsteady, because the thickness of the sediment layer varies both in the time of the separation process and in the length of the membrane module. The influence of the sediment layer on the hydrodynamics and mass transfer efficiency, its productivity, and the quality of purification is determined. The calculation of the sediment layer and its influence on the separation process is performed using the microprocess method. This method is based on material and energy balances and takes into account viscosity and diffusion coefficients, which vary depending on the temperature and composition of the mixture. The dependences of the sediment thickness on time and the length of the membrane module and selectivity coefficients on the concentration of the colloidal solution are obtained to determine the effective parameters of the baromembrane installation.

Environmentally Friendly Water-Based Self-Crosslinking Acrylate Dispersion Containing Magnesium Nanoparticles and Their Films Exhibiting Antimicrobial Properties

A water-based polymeric acrylate dispersion (latex) containing MgO nanoparticles, which had been added at a concentration of 1.5% (with respect to the monomers) during the preparation procedure, was investigated as an environmentally friendly binder for sanitary interior paints. The properties of this new latex were compared to those of a reference system free of the magnesium nanoparticles, synthesized by the same route, i.e., by semi-continuous emulsion polymerization. Tests were made in order to ascertain the mechanical and chemical properties, flash corrosion resistance and antimicrobial effect of the latex films. The results revealed that the new latex containing magnesium nanoparticles provided solvent-resistant coating films having pronounced antimicrobial activity against all the tested bacterial and fungal strains. The desirable antimicrobial properties can be ascribed to the sharp-edged character of magnesium nanoparticles, the peroxidation of lipids and the formation of reactive oxygen species. Moreover, no flash corrosion was formed beneath coating films containing magnesium nanoparticles, which can be attributed to the alkaline action due to the dissolution of a fraction of MgO in latex medium. The results of all of the tests provided evidence of the superiority of the polymeric dispersion with the magnesium nanoparticles to the reference system containing no nanoparticles.

The effectiveness of asbestos stabilizers during abrasion of asbestos-cement sheets

The effectiveness of different organic stabilizers in stabilizing asbestos in fiber cement was evaluated using brush-abrasion tests on asbestos-cement (AC) sheets and counting the number of released respirable fibers using phase-contrast microscopy (PCM). All asbestos fibers released from the abraded sheets were identified as chrysotile. The binding effectiveness of the stabilizers varied from 35% (bitumen-based) to >90% (polyurethane resin (PUR), acrylic paint, flexible coating). Stabilizers with low binding efficiency, i.e., <80%, should not be used for coating. The 80% binding efficiency limit is suggested based on the performance of PUR stabilizer applied to the surfaces of AC sheets that were primarily in good condition. With very deteriorated surfaces, even the best performing stabilizers will not prevent fiber release on a scale comparable to that from unprotected sheets in good condition. The greatest effectiveness in binding asbestos fibers is achieved by applying stabilizers that combine a hard coating (PUR), high degree of flexibility (flexible coating) and adhesiveness (acrylic dispersion paint). A simple brush-abrasion test is recommended as an inexpensive, fast and reliable method for evaluating the performance of stabilizers. The brush-abrasion test can reveal invisible deterioration of the cement matrix weakening asbestos-fiber attachment to AC sheets.

Textile-based thermoelectric generator fabricated from carbon fibers

This paper presents a textile-based thermoelectric generator (T-TEG) with 105-pair thermocouples fabricated from carbon fibers as basic material. The carbon fiber used in this study was in a tow form which contains 3000 filaments. This tow was inserted into polyester fabric by hand to form a series of float yarns on the fabric. After acetone treatment, roughly every half of the floats on both sides of the fabric was covered by acrylic dispersion to resist nickel particles during electroplating in order to get a chain of carbon-nickel thermojunction. After the acrylic dispersion was completely polymerized, the sample was electroplated in the plating solution containing nickel acetate, boric acid, and sodium dodecyl sulfate. Subsequently, the sample was washed and dried. This T-TEG was fabricated on a small piece of fabric around 12 cm × 12 cm which contains 105-pair of carbon fiber and nickel-coated carbon fiber forming a thermopile. To study its electrical properties, this T-TEG was characterized to obtain the voltage-temperature curve, the voltage-current characteristic, the output power versus current and the maximum power versus temperature. Characterization results of this T-TEG show characteristics of a typical thermoelectric generator. Scanning electron micrograph images and EDS spectra were also examined to see the nickel deposition on the carbon fiber surface.

Silicone acrylate dispersion based on semi-continuous seed emulsion polymerization using polymerizable emulsifiers

The silicone modified acrylate dispersion was successfully prepared by semi-continuous seed emulsion polymerization, in which methyl methacrylate (MMA) was used as a hard monomer, butyl methacrylate (BA)was used as a soft monomer, and a double bond-containing polymerizable emulsifier ammonium allyloxtmethylate nonylphenol ethoxylates sulfate (DNS-86)and potassium persulfate (KPS)were utilized as emulsifiers and initiators, respectively. A functional monomer, benzyl methacrylate (BZMA), and a modified monomer, vinyltriethoxysilane (VTES), were introduced into the base dispersion. The factors, which have an influence on emulsion polymerization performance, were optimized. At the same time, the dispersions prepared with conventional emulsifiers and polymerizable emulsifiers were compared under the same conditions. The structure and properties of the synthetic dispersion were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA). The results showed that the optimum preparation conditions of the dispersion are as follows: The amount of emulsifier was 3%, the amount of initiator was 0.5%, main monomer ratio was 1:1, the amount of functional monomer BZMA and VTES was 3%, respectively. The dispersion obtained by using DNS-86 had better thermal stability, chemical stability and the dispersion was uniformly blue, which represented small particle size. After modification, the film showed higher hydrophobicity.

Creation of Biocidal Coatings using the Stabilization of Silver Nanoparticles in Aqueous Acrylic Dispersions

Creation of Biocidal Coatings using the Stabilization of Silver Nanoparticles in Aqueous Acrylic Dispersions

Дослідження полімерних плівок на основі суміші дисперсій стирол-акрилових сополімерів

The article presents the results of a study of the physical, mechanical, structural and chemical properties of polymer films based on a mixture of styrene acrylic aqueous dispersions Akratam AS 02.1 and Akratam AS 03.1. The physical and mechanical properties of individual and combined polymer films were evaluated in terms of transparency, stickiness, thickness, surface density and elongation at break. Individual styrene acrylic film Akratam AS 02.1 is characterized by high elasticity and stickiness, and Akratam AS 03.1. dispersion forms a strong, hard and brittle film. It was found that an increase in the concentration of Akratam AS 03.1 in the polymer mixture Akratam AS 02.1 / Akratam AS 03.1 leads to a decrease in stickiness, thickness, surface density and the degree of deformation of the combined film. Changes in the structural parameters of the network of combined polymer films depending on the concentration of the components in the mixture were studied using the sol-gel method. It was determined that the individual film Akratam AS 02.1 has a high content of the soluble fraction (28.5%), which is due to the low degree of intermolecular crosslinking (1.221). For films of the composition Akratam AS 02.1 / Akratam AS 03.1 90:10 and 50:50, an increase in the degree of crosslinking and a decrease in the sol fraction to 27.6 and 27.3% are observed, respectively. The obtained data on the structural characteristics of the polymer network of the studied films correlate with the results of determining the effect of the composition of the polymer mixture on the hydrolytic stability of the combined film. The greatest indicators of resistance to the action of cold, hot water and soap-soda solution are characteristic for the film of the composition Akratam AS 02.1 / Akratam AS 03.1 50:50 and are 98.3, 97.8 and 98.7%, respectively. Thus, the mixed styrene acrylic films of the composition Akratam AS 02.1 / Akratam AS 03.1 90:10 and 50:50 can be used to form a polymer coating on a textile material with improved performance properties. Key words: polymer film, styrene acrylic dispersion, polymer mixture, physical and mechanical properties, structural parameters of the network, hydrolytic stability.

EFFECT OF ARTIFICIAL WEATHERING AND TEMPERATURE CYCLING ON THE ADHESION STRENGTH OF WATERBORNE ACRYLATE COATING SYSTEMS USED FOR WOODEN WINDOWS

ABSTRACTThe adhesion of coatings to wood is important for their long-term performance. In this study, the adhesion strength of water-based acrylate coatings used for wooden windows after exposure to artificial weathering (AW) and temperature cycling (TC) was investigated. The analysis of the adhesion quality of coatings was performed via a pull-off test and failure characteristics. The 3-layered and 4-layered white and brown acrylate dispersions from six different producers were compared and the effect of coating thickness on adhesion strength was investigated. The adhesion strength values proved to be very variable. After AW, the adhesion strength and its variability increased for all the samples. TC had no statistically significant effect on the adhesion strength values. White coating systems were initially characterized by lower adhesion strength, but after AW and TC, they reached higher adhesion strength values than brown ones. The overall highest adhesion after AW and TC was recorded for the coatings based on alkyd-acrylate hybrid basis (Producer 3), while the lowest adhesion variability after AW was measured for one type of tested acrylate coating (Producer 4). The effect of different layering on adhesion strength was not demonstrated in this study.

Relation between microstructure, technical properties and neutron radiation shielding efficiency of concrete

The paper presents a study on the properties of New Generation Shielding Concrete (NGS-Concrete) modified by materials containing fast neutron moderators and thermal neutron absorbers. The reference ordinary concrete (OC) was modified by the change of the coarse aggregate from crushed granite to magnetite one and cement from CEM III 42.5N to CEM I 42.5R. The addition of gadolinium oxide, polypropylene macro- or/and microfibers, acrylic dispersion, acrylic dispersion together with gadolinium oxide, epoxy dispersion, and finally the inorganic chemical compound containing boron (NaBH4) was used as well. The experimental program included: microstructure studies (analysis of fracture surface, visual and image analysis of cross sections, observations using scanning electron microscopy – SEM, volume and absolute density and total porosity calculated from gravimetric measurements), compressive strength, ultrasonic pulse velocity (UPV) as well as neutron radiation shielding efficiency measurement expressed as half value layer (HVL), determined by the neutron radiation equivalent dose reduction. The relations were investigated using a multiple regression analysis of experimental results. A good correlation between the compressive strength and ultrasonic pulse velocity for all concretes was confirmed. The neutron radiation shielding efficiency expressed as HVL was mainly influenced by volume density (VD). The mathematical model HVL (VD) turned out to be the most reliable, whereas any other independent variable added to this bivariate model was statistically not significant. It was concluded that neutron radiation shielding depends on the volume density of concrete, which is determined mainly by phase and atomic composition changes of aggregate and a lesser extent by microstructure changes.

The Influence of Macromolecular Structure and Composition on Mechanical Properties of Films Cast from Solvent‐Free Polyurethane/Acrylic Hybrid Dispersions

AbstractPolyurethane (PU) /acrylic dispersions are of great commercial interest due to the synergetic combination of the PU and acrylic polymers. In this work, a series of PU/acrylic dispersions is synthesized by a solvent‐free technique and the influence of colloidal structure, grafting between the two polymers, and the nature of the two polymer phases themselves on the mechanical properties of films cast from the dispersions is explored. TEM analysis shows that the particles have a PU shell/acrylic core structure which is translated into the morphology of films cast from the dispersions. This particle/film morphology leads to the acrylic copolymer acting as a filler material and allows high Tg copolymers to be employed, leading to films with very high mechanical strength. Grafting of the PU and acrylic phases leads to increased compatibility but has little effect on the mechanical properties which are largely determined by the hardness of both the diol used in the PU synthesis and more importantly the acrylic (co)polymer composition. This work allows us to propose a series of design principles in order to synthesize PU/acrylic hybrids with controlled mechanical properties.

The role of agar gel in treating water stains on acrylic paintings: Case study of Composition, 1963 by Justin Knowles

ABSTRACTThis paper describes the historic context and explains the treatment rationale for minimizing disfiguring water stains on a large-scale, acrylic dispersion canvas painting: Composition, 1963, by British artist Justin Knowles. Composition is a brightly colored, hard-line geometric abstraction juxtaposed against an unpigmented acrylic dispersion-sized linen canvas. Accidental water damage produced tidal stains across the sized canvas, rendering it unexhibitable. Investigations into the relationship between materials and meaning in Knowles’ work, alongside literature on the cleaning of acrylic dispersion paintings, textiles, and works on paper facilitated the development of a tailored cleaning treatment involving the use of agar gel as an aqueous delivery system, which minimized risk to the painting materials, whilst facilitating a satisfactory reduction and subsequent visual integration of the water stain. As a final stage, a number of retouching media commonly used on acrylic paints were evaluated, and a successful method was determined using Aquazol 50 and dry pigments. The success of retouching was also evaluated via visual assessment, highlight-based RTI, and digital microscopy (HIROX). As a result of this collaborative approach, this important work has been successfully returned to displayable condition.

Pressure sensitive adhesives with post-crosslinking ability based on acrylic dispersions obtained from solvent-borne copolymers

This work presents a novel aqueous dispersion prepared from a solvent-borne acrylic copolymer mixture containing carboxylic acid groups for the first copolymer and epoxy groups for the second copolymer. The aim of this work was to test the suitability of the presented dispersion for the preparation of pressure sensitive adhesives (PSA) with post-crosslinking ability. A monomodal particle size distribution was obtained and a successful coemulsification of both copolymers into one particle was proved, although the epoxy containing polymer did not bear carboxylic acid groups. Storage of the dispersion led to intraparticular crosslinking inside the particles, which produced an increase in the shear of the PSA. Post-crosslinking ability was shown for the PSA of the unaged and aged dispersions in the presence of 1-methylimidazole and led to a major increase in shear but did not lead to a considerable decrease in peel. Probe-tack enabled a fast detection of post-crosslinking because of the appearance of a plateau formation in probe-tack curves. The adhesive properties before and after crosslinking demonstrate the potential of the presented dispersion, which yields novel PSA for applications which need high shear but also sufficient peel.

Ultrasound measurement of exterior wood coating thickness

The present paper deals with the measurement of coat thickness on wood using an ultrasonic measurement method. Exterior wood coatings (waterborne acrylate dispersions) with coating film thickness between 80 – 115 µm were examined. The non-destructive film thickness measurement used a Sursonic ultrasound measuring device, enabling measurement of the thickness of thin films on non-ferromagnetic and simultaneously non-conductive materials. The device also enables measurement of very thin layers of coating films, where the transit time of an ultrasound pulse through the film is shorter than the time width of the pulse. The accuracy of measurement using this measuring device was determined; destructive measurement using a light microscope was chosen as a reference measurement method. Differences in the results measured using the destructive and non-destructive methods were recorded; nevertheless, in most cases, these differences are smaller than the uncertainty of measurement using the light microscope. It can be concluded, therefore, that the results of the two compared methods match over the entire range of thickness of 80 – 115 µm. The largest differences in the measurement readings from the destructive and non-destructive methods were identified in the range of 97 – 103 µm.

Toward a Green Synthesis of Polyurethane/(Meth)acrylic Dispersions through Control of Colloidal Characteristics.

Polyurethane (PU)/acrylic waterborne hybrids are an attractive class of materials with wide application possibilities, but their synthesis typically requires significant quantities of solvent which has negative economic and environmental consequences. In this work, solvent-free and surfactant-free polyurethane (PU)/acrylic waterborne hybrids were obtained by synthesizing the PU prepolymer containing carboxylic groups directly in (meth)acrylic monomers that act as solvent. Then, the mixture is dispersed in water; the PU is chain-extended with diamines, and the (meth)acrylic monomers are polymerized. It was found that, against expectations, colloidal stability did not improve with the concentration of carboxylic groups that acted as stabilizing moieties. A combination of MALDI-TOF MS analysis and Monte Carlo simulations revealed that the highly heterogeneous compositions of the short chains of the PU prepolymer and their reaction with the chain-extender in the aqueous phase were responsible for lack of control of the colloidal properties. This problem was overcome by using more hydrophobic chain-extenders that decrease the fraction of PU chains in the water phase. In this way high-solid-content stable dispersions with controlled particle size were obtained. Finally, the properties of the PU/(meth)acrylic films were studied in terms of mechanical properties and water resistance.

Conservation of Subfossil Bones from a Lacustrine Setting: Uncontrolled and Controlled Drying of Late Quaternary Vertebrate Remains from Cold Lake, Western Canada

Abstract Water-saturated vertebrate remains (e.g., bone, antler, and ivory) are particularly challenging to stabilize for long-term storage, research, and analysis. These types of specimens are sensitive to damage caused by water loss, which frequently results in delamination, twisting, and cracking. The recovery of late Quaternary vertebrate remains from underwater areas of Cold Lake, western Canada, prompted us to conduct a series of analyses to better understand the preservation of the remains and their susceptibility to damage, and to test different conservation techniques to achieve successful drying. X-ray fluorescence analysis of a sample of specimens revealed that the remains have particularly high iron concentrations, a condition that might have contributed to weaken their structure, further compromising their integrity when drying. Additionally, we found that certain bone elements, such as long bones, are more susceptible to severe surface delamination than others, and as a result these specimens should be monitored more closely during their treatment. Of the four drying methods we tested, controlled air-drying produced the best results, followed by solvent-drying. In contrast, vacuum freeze-drying and vacuum freeze-drying with 20% v/v Acrysol WS-24 in water, an acrylic dispersion, while rapid, resulted in differing degrees of delamination and cracking.

Synthesis and Utilization of Low Dispersity Acrylic Macromonomer as Dispersant for Nonaqueous Dispersion Polymerization

The effect of dispersity on the stabilization performance of poly(butyl methacrylate) (P(BMA)) ω-unsaturated macromonomer used as a reactive dispersant in nonaqueous acrylic dispersion (NAD) polymerization is investigated for the first time. Macromonomer with low dispersity (1.3) is synthesized in a one-pot process by the addition of bis(difluoroboryldiphenylglyoximato)cobalt(II) (CoPheBF) as a catalytic chain transfer (CCT) agent to P(BMA) chains mediated by atom transfer radical polymerization (ATRP); addition of the CoPheBF at a BMA monomer conversion of ∼80% leads to good control of chain length and dispersity while achieving a high fraction of terminal double bond (TDB) functionality. The lower dispersity P(BMA) macromonomer provides better stabilization to NAD systems per dispersant chain compared to material of the same number-average molecular weight (∼6000 Da) and TDB functionalization (∼70–75%) but higher dispersity (1.8), as characterized by the smaller average particle sizes and the higher wei...

MODIFICATION OF POLYESTER FIBERS TO CREATE COMPOSITE MATERIALS WITH ADJUSTABLE RIGIDITY

Research aims at experimental study of an effective method of creating polymer-fiber composite materials with a comb structure of an interfacial layer. To change the surface micro-relief of polyester fiber method of surface saponification in the presence of a quaternary ammonium compound was used. This method provides localized hydrolysis reacting of polymer to form dotted etch wells. Fiber modification allows synthesizing comb polymer chains of the binder with the penetration of the lateral branches into the formed pore spaces of the textile carrier. Condition of polyester fiber after saponification estimated by indices: a loss of fiber mass, specific breaking load of the material, the content of carboxyl groups, the sorption of acrylic dispersion. The criterion for the rapid assessment of the quality of the fiber modification to change the micro-relief of its surface can serve the magnitude of the fiber mass loss, which must not exceed 3 %. Estimating the size of the formed voids was carried out according to the nitrogen adsorption data using a sorption analyzer NOVA 1200e. In moderate alkaline hydrolysis conditions, the main increase in the internal free volume provides mesopores with a diameter of 35...40 nm. The formations of a sub microscopic size 7...8 nm are the most numerous. Assessment of nanosized condition of reinforcing polymer dispersion by dynamic light scattering method allows recommending the necessary depth of polyester fiber hydrolysis to ensure the effects of the composite material stiffness controlled increase in 10...16 times.

Sustainable Approach to Superhydrophobic Surfaces Based on Water‐Born Electrospinning

AbstractSuperhydrophobic surfaces are obtained by a sustainable approach by electrospinning of water‐based acrylate dispersion followed by mild silanization and removal of template polymer. The resulting nonwovens show very high superhydrophobicity and very low roll angle. In contrast to many other approaches, pores provide the required morphology to achieve superhydrophobicity. This new material provides a new approach to electrospun nonwoven coatings which can be of interest for textile applications.

The new method of manufacturing porous castings from styrene–acrylic dispersion

This work presents an innovative method for producing porous castings from polymer dispersion with wood flour. The method described for forming porous castings from blends, in which the aqueous dispersions of polymers are binders, enables the manufacturing of wood-like products with a cork-like structure. The casting technology and selected properties of finished castings (density, compression strength) are presented. The structurual investigations of the obtained castings are also presented.