Effect of Polymer Additives on the Microstructure and Mechanical Properties of Self-Leveling Rubberised Concrete

The materials based on concrete with an addition of rubber are well-known. The interaction between concrete components and rubber particles is in the majority cases insufficient. For this reason, different substances are introduced into concrete-rubber systems. The aim of this paper is to establish the influence of five different polymer additives, i.e., 1. an aqueous dispersion of a styrene-acrylic ester copolymer (silanised) (ASS), 2. water dispersion of styrene-acrylic copolymer (AS), 3. anionic copolymer of acrylic acid ester and styrene in the form of powder (AS.RDP), 4. water polymer dispersion produced from the vinyl acetate and ethylene monomers (EVA), 5. copolymer powder of vinyl acetate and ethylene (EVA.RDP)) on the properties of the self-leveling rubberised concrete. Scanning electron microscopy has allowed to establish the interaction between the cement paste and rubber aggregates. Moreover, the compressive strength and flexural strength of the studied materials were evaluated. The results indicate that the mechanical properties depend extensively on the type as well as the amount of the polymer additive introduced into the system.

Investigation into the effect of resin finish on the functional characteristics of plain fabrics using different curing methods

Purpose Cellulosic fabric and plain weave are the most commonly used material in home textiles. The poor wrinkling, dimensional stability and pilling are some of the problems faced during usage. The textile industries apply resin finish to improve these characteristics. The purpose of this study is to improve pilling resistance, dimensional stability and smoothness appearance (SA) of rayon and rayon/cotton plain fabrics using different concentrations of dimethyloldihydroxyethylene urea (DMDHEU) and acrylic copolymer. The finish was fixed using two different fixation methods. Design/methodology/approach Three concentrations, 40, 100 and 150 g/l of Arkofix NF (DMDHE based) and Appretan N9211 (acrylic copolymer), were taken. The finish was applied at normal and shock cure. The effects of finish on pilling resistance, dimensional stability, smoothness, tear strength, light fastness, Berger whiteness and yellowness index of plain fabrics were investigated. Findings The changes in the characteristics of the finished fabrics were compared with unfinished fabrics. This study revealed that at 40 g/l of Arkofix NF and Appretan N9211 using a normal cure would improve the pilling resistance, dimensional stability and SA of the plain fabrics. Whereas, there was no adverse effect observed on tear strength, light fastness, Berger whiteness and yellowness index of plain fabrics at these conditions. Originality/value Unlike the previous studies, this paper proposed the single finish formulation where the functional characteristics of the plain rayon and rayon cotton fabrics meet the general requirement of a customer.

Influence of Polymer Modifiers on Selected Properties and Microstructure of Cement Waterproofing Mortars

This paper presents the results of research on the influence of polymer modifiers: styrene-acrylic copolymer, vinyl acetate/ethylene (EVA), vinyl acetate/acrylic copolymer (VAAc), and VA/VeoVa/acrylic terpolymer on the water permeability and adhesion of cement-containing waterproofing mortars in concrete. The content of the polymers in the composition of the mortars was 15, 20 and 26% (m/m) in relation to the weight of the dry ingredients. Using microscopic methods, an attempt was made to analyse the relationship between the microstructure of the mortars and the properties of these polymers. The EVA and the vinyl acetate/acrylic copolymer, which were used in the form of dry powders, had the most favourable effect on water permeability and adhesion to the concrete substrate. They may prove to be useful for the production of one-component cement-containing waterproofing mortars. On the other hand, the VA/VeoVa/acrylic terpolymer modifier had the least favourable effect on the tested properties. For mortars with this modifier, the desired water-permeability parameters were not achieved. Depending on the amount of polymer modifier, the mortars were characterized by differences in watertightness, as established on the basis of changes in porosity and differences in the adhesion of the cement-polymer paste to the surface of aggregate grains. It was determined that the type of polymer and its dispergation properties influence the water permeability of mortars, as well as their adhesion to concrete substrates.

How Does EOR Polymer Impact Scale Control During ASP Flooding?

Polymer based enhanced oil recovery (EOR) technology has drawn more and more attention in the oil and gas industry. The impacts of EOR polymer on scale formation and control are not well known yet. This research investigated the impacts of EOR polymer on calcite scale formation with and without the presence of scale inhibitors. Seven different types of scale inhibitors were tested, including four different phosphonate inhibitors and three different polymeric inhibitors. Test brines included severe and moderate calcite scaling brines. The severe calcite brine is to simulate alkaline surfactant polymer (ASP) flooding conditions with high pH and high carbonate concentration. The test method used was the 24 hours static bottle test. Visual observation and the residual calcium (Ca2+) concentration determination were conducted after bottle test finished. It was found that EOR polymer can serve as a scale inhibitor in moderate calcite scaling brines, although the required dosage was significantly higher than common scale inhibitors. Strong synergistic effects were observed between EOR polymer and phosphonate scale inhibitors on calcite control, which can significantly reduce scale inhibitor dosage and provides a solution for calcite control in ASP flooding. The impact of EOR polymer on polymeric scale inhibitors varied depending on polymer types. Antagonism was observed between EOR polymer and sulfonated copolymer inhibitor, while there was weak synergism between EOR polymer and acrylic copolymer inhibitors. Therefore, when selecting scale inhibitors for polymer flooding wells in the future, the impact of EOR polymer on scale inhibitor performance should be considered.

Mechanical Properties of Gypsum-PCM Composite Refined with the Acrylic Copolymer

Nowadays, the construction sector is changing rapidly towards more energy-efficient solutions. Many companies strive to improve the properties of building materials by reducing the weight of materials, increasing mechanical properties, and improving insulation properties. Therefore, to bring closer the problems that need to be solved, it was proposed to develop a new gypsum composite that will be used in a drywall. In addition, phase change material (PCM) and copolymer were used to improve thermal properties and tighten the final product against paraffin leakage. The main goal of the study was to check the mechanical properties. The results of endurance tests were presented. Based on that, it was determined that PCM affects the strength properties of the gypsum. In analyzing the obtained results, it can be stated from a mechanical point of view that to a certain extent, it was possible to confirm the correctness of using PCM in gypsum with an acrylic copolymer. The other part of the article presents the course of research and the results confirming the presented hypothesis.

The Effect of Different Soft Core/Hard Shell Ratios on the Coating Performance of Acrylic Copolymer Latexes

Core–shell acrylic copolymer latexes containing bio resourced itaconic acid with different compositions in respect with the core and shell segments were synthesized, characterized, and applied as coating materials for leather. The purpose of the study was to evidence the high coating performance of the latexes when the ratio of the core/shell differed from 90/10 to 50/50 wt %. The copolymers were prepared via emulsion copolymerization technique and the products were isolated and characterized by means of structure identity, thermal behavior (DSC and DMTA), coating performance. The particle size of the latexes varied from 83 to 173 nm with the variation of the ratio of core/shell segments. The influence of the composition of soft part and hard part was highlighted in the thermal and coating properties. The optimal composition giving the best coating performance could be determined as DS 60/40. Further increase of the hard segment content, resulted in decreased emulsion stability and the coating performance on the leathers. The use of itaconic acid seemed to increase the emulsion stability as well the adhesion of the latexes to the substrate.

USE OF ACRYLIC COPOLYMER ADDITIVE SOIL STABILIZATION PLUS FOR PREPARATION OF MIXTURES MADE BY COLD RESYCLING TECHNOLOGY AND CRUSHED STONE-SAND MIXTURES IN PAVEMENT FOUNDATION LAYERS

ntroduction. Rehabilitation of public roads network requires a comprehensive recovery with strengthening of the bearing capacity of the pavement foundation. Rehabilitation of the foundation bearing capacity performed by arranging layers of road material made by cold recycling technology (hereinafter — CRRM) in accordance with [4] or by arranging a layer of crushed stone — sand mixture reinforced with cement or complex binder (hereinafter — CSSM 20) according to [13]. Purpose. The purpose of the work is to study the feasibility of using acrylic additives for the preparation of mixtures made by cold recycling technology and crushed stone-sand mixtures treated with cement in the layers of pavement foundation. Materials and methods. Experimental comparative tests of CRRM and CSSM 20 with different content of complex binder were performed. Results. Feasibility of acrylic additives use has been established (hereinafter — the additive) for the preparation of CRRM and CSSM 20 in the pavement foundation layers. Recommendations on technological parameters of preparation, transportation, laying and compaction of mentioned mixtures are given. Conclusions. Performed researches have shown that according to physical and mechanical indicators CRRM and CSSM20 meet the requirements of the current normative documents of Ukraine. The advantages of use are noted.