scholarly journals Enhancement the Properties of Construction Urea Composition with Polymer Additive

2021 ◽  
Vol 2 (2) ◽  
pp. 1-8
Author(s):  
Arslanov Islom Kimsanovich

This scientific article provides physicochemical studies where the addition of a gel polymer has a positive effect on the process of structure formation. The presence of chemical bonds between the components, a change in the morphology of the structure, a decrease in microporosity, an increase in the density and thermal stability of the urea composition are shown. Polymer composite materials are used as chemically resistant coatings, polymer mortars and polymer concretes. Along with such valuable properties as incombustibility, colorlessness, good miscibility with water, etc., urea resins and compositions based on them have a number of disadvantages. The object of the study is a carbamide composition with a quartz filler and an addition of a gel polymer, its structure formation and chemical resistance. The methodological basis of the study is the polystructural theory of composite building materials (CBM) and the modeling of the study of the chemical resistance of the urea composition in aggressive conditions. The issues of finding effective water-binding additives and studying their effect on structure formation, properties and technology of urea compositions remain relevant and require additional research. It is shown that with the optimal content of the gel-polymer additive in the composition of 0.13% of the filler weight, the compressive strength and specific impact strength increase by 17; 13% and shrinkage is reduced by 7%. It was found that due to the enhancement of the adhesive bond between the components and the improvement of the pore structure under the action of the gel-polymer additive, the chemical resistance of the urea composition with quartz filler increases. So, water, acid and alkali resistance are 0.75; 0.80 and 0.85 and which, respectively, are 6, 7 and 7 points higher than the reference composition.

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 240
Author(s):  
Fei Shuo Hung

In construction process, the formwork must be in contact with concrete to help the concrete solidify and fix the shape. Coating the formwork with a polymer can prolong its service life by reducing the amount of concrete sticking to the mold. Herein, an aluminum template substrate was coated with polyvinylidene difluoride (PVDF) or polyurethane (PU). Aluminum template material analysis was conducted, polymer film thickness was measured, and weather, moisture, pollution, salt spray, abrasion, impact, and acid and alkali resistance tests were conducted, as were tensile, bending, adhesion, hardness, and salt water resistance tests. Cement adhesion resistance was repeatedly tested. The experimental results indicated that the PVDF-coated template was superior. The novel PVDF Aluminum template exhibited high corrosion resistance and can be used in building materials, for example, in ceilings, partition walls, curtain walls, roof panels, and roof trusses. For reference, it can also be applied to ship structures and seaside and wind power generation projects.


2020 ◽  
Vol 3 (2) ◽  
pp. 19-28 ◽  
Author(s):  
A. Volodchenko

one of the possible ways to improve the properties of building materials is to modify the processes of structure formation, which can be realized through the use of crystalline primers. In this regard, it is urgent to study the effect of artificial calcium hydrosilicates on hardening processes, as well as the properties of non-autoclave silicate materials based on non-traditional aluminosilicate raw materials. Studies have shown that the addition of artificial calcium hydrosilicates (CSH) in an amount of 1-1.5 wt. %, when the content in the mixture of CaO is less than 10 wt. %, effectively increases the strength parameters of products at all stages of heat and moisture treatment from 8 to 16%. The most intense increase in strength is observed during the heat-moisture treatment (TBO) from 3 to 6 hours and is at least 13%, while in samples without the addition of artificial calcium hydrosilicates, the strength increase is 6%. The addition of artificial calcium hydrosilicates intensifies the processes of structure formation, which ensures an increase in crystalline matter, and, due to the fibrous structure, acts as a fiber, which contributes to the nano-reinforcement of the cementing substance formed from neoplasms in the CaO-SiO2(Al2O3)-H2O system based on clay rocks and calcium oxide. Due to the accelerated set of strength, it is possible to reduce the duration of isothermal exposure while maintaining the necessary performance characteristics.


Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1885
Author(s):  
Xinyu Wu ◽  
Feng Yang ◽  
Jian Gan ◽  
Zhangqian Kong ◽  
Yan Wu

The silver particles were grown in situ on the surface of wood by the silver mirror method and modified with stearic acid to acquire a surface with superhydrophobic and antibacterial properties. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray energy spectroscopy (XPS) were used to analyze the reaction mechanism of the modification process. Scanning electron microscopy (SEM) and contact angle tests were used to characterize the wettability and surface morphology. A coating with a micro rough structure was successfully constructed by the modification of stearic acid, which imparted superhydrophobicity and antibacterial activity to poplar wood. The stability tests were performed to discuss the stability of its hydrophobic performance. The results showed that it has good mechanical properties, acid and alkali resistance, and UV stability. The durability tests demonstrated that the coating has the function of water resistance and fouling resistance and can maintain the stability of its hydrophobic properties under different temperatures of heat treatment.


2020 ◽  
Vol 5 (2) ◽  
pp. 77
Author(s):  
Anissa Diyah Lestari ◽  
Luky Indra Gunawan ◽  
Dyah Julia Syifa ◽  
Ronny Wahyu Wibowo ◽  
Hendramawat Aski Safarizki

AbstrakPada era teknologi sekarang ini, beton adalah sebagai salah satu bahan bangunan yang paling banyak digunakan di Indonesia. Inovasi diperlukan untuk peningkatan mutu beton dalam kuat tekan beton dan harga lebih murah dibandingkan dengan beton normal. Limbah penambangan batu kapur di Wonogiri tidak dimanfaatkan dengan baik. Sehingga menimbulkan polusi udara dan mencemari lingkungan di sekitar penambangan. Maka dari itu, inovasi ini menggunakan limbah kalsit untuk ditambahkan sebagai bahan tambah pembuatan beton. Luaran yang diharapkan dalam penelitian ini adalah dapat mengetahui komposisi yang pas untuk penambahan kalsit dalam campuran pembuatan beton dan menjadikan beton dengan bahan tambah limbah kalsit sebagai beton inovatif ramah lingkungan dan memiliki nilai ekonomis. Serta draft artikel ilmiah tentang beton inovatif yang dituangkan dalam sebuah draft artikel ilmiah, laporan kemajuan dan laporan akhir. Hasil yang telah dicapai saat ini berdasarkan indikator keberhasilan jangka pendek, yaitu telah dilaksanakannya penelitian dan pembuatan beton dengan bahan tambah kalsit dengan beberapa varian, serta pengujian sampel beton setelah berumur 14 hari. Pada penelitian ini mengetahui komposisi optimum penambahan kalsit terhadap kuat tekan beton, dengan penambahan kadar kalsit sebesar 5%, 9%, dan 15% benda uji yang digunakan adalah silinder berdiameter 15 cm dengan tinggi 30 cm sebanyak 9 buah dimana pengujian dilakukan pada umur 14 hari. Hasil analisis data pengujian kuat tekan beton kalsit adanya peningkatan pada variasi 9% kalsit sebesar 20,71 MPa (4.12%) dibandingkan beton normal 19,89 MPa. Maka kesimpulannya penggunaan kalsit dapat meningkatkan kuat tekan beton.Kata Kunci: Efektivitas, Beton SCC, Kalsit, Kuat TekanAbstractConcrete is one of the most widely used building materials in Indonesia In the current technological era. Innovation is needed to improve concrete quality in concrete compressive strength and prices are cheaper than normal concrete. Waste from limestone mining in Wonogiri is not utilized properly. So that it causes air pollution and pollutes the environment around mining. Therefore, this innovation uses calcite waste to be added as an ingredient to add concrete. The expected output in this study is to be able to find out the right composition for the addition of calcite in a mixture of concrete making and to make concrete with calcite added waste as an innovative concrete that is environmentally friendly and has economic value. As well as the draft scientific article about innovative concrete as outlined in a draft scientific article, progress report and final report. The results that have been achieved at present are based on short-term success indicators, namely the research and manufacture of concrete with calcite added ingredients with several variants, as well as testing of concrete samples after being 14 days old. In this study, the optimum composition of calcite was added to the compressive strength of concrete, with the addition of calcite levels of 5%, 9%, and 15%. The test material used was a cylindrical diameter of 15 cm with a height of 9 cm in which testing was done at 14 days . The results of the analysis of the test data for compressive strength of calcite concrete was an increase in the variation of 9% of calcite by 20.71 MPa (4.12%) coMPared to normal concrete of 19.89 MPa. So the conclusion is the use of calcite can increase the concrete compressive strength.Keywords: Effectiveness, SCC Concrete, Calcite, Compressive Strength


2013 ◽  
Vol 454 ◽  
pp. 158-162 ◽  
Author(s):  
Guo Yi Li ◽  
Xiao Hui Wang ◽  
Yan Jie Wei

Inorganic ceramic membrane has been one of the hottest research field both in environmental protection and materials, as it has so much advantages, such as, high-temperature-resistance ,acid and alkali-resistance , adequate distribution of aperture , steady chemical property , high strength , large flux, long lifetime, anti-pollution, simple structure, small footprint, few corollary equipment, easy installation, no chemical additives, high separating efficiency, high degree of automation control and so on. Some application on environmental progress in the field of inorganic ceramic membrane technology applied in treatment of food industry wastewater, mechanical metallurgy wastewater and petrochemical wastewater was summarized in this paper, and the existent problems and the future research direction was discussed.


2017 ◽  
Vol 18 (1) ◽  
pp. 203-213 ◽  
Author(s):  
Chengchao Guo ◽  
Xuanxuan Chu ◽  
Fuming Wang

Abstract Tailings reservoirs generally consist of a tailings dam, a tailings conveying system and a drainage system, which are indispensable facilities and provide security and environmental protection for storing tailings and clarifying water in some industries (e.g., metallurgy, non-ferrous building materials, nuclear and chemical industries). Consequently, consolidating seepage prevention and treatment is important. When applied to seepage prevention works for tailings reservoirs, current seepage prevention technologies can cause destruction of the dam and require further construction sites. It is therefore essential to adopt new types of advanced and practical technologies. Aimed at studying the feasibility of the application of non-water reaction polymer grouting technology in seepage prevention of tailings reservoirs and acquiring the properties for practical engineering, an analysis of the environmental impact, chemical resistance and permeability of the polymer material, and the main technical characteristics of the polymer cutoff wall was conducted. The test results showed that the polymer grouting technology applied to seepage prevention works of a tailings reservoir caused little disturbance to the dam, possessed good anti-seepage performance and perfect durability. This study may provide a reference for the seepage control of tailings reservoirs.


2021 ◽  
Vol 6 (1(62)) ◽  
pp. 36-42
Author(s):  
Oleksandr Kovalchuk ◽  
Viktoriia Zozulynets

The object of the research is the process of directed structure formation in the body of alkaline concrete, made using a reactive aggregate, in this case, basalt, and the process of deformation development in such concrete. The problem with using reactive aggregates is that they cause alkaline corrosion. It manifests itself in the form of cracks and layers of gel-like substances that form at the point of contact of the aggregate with the cement stone. During the research, methods of physical and chemical analysis were used (X-ray phase, differential thermal and thermogravimetric analyzes, electron microscopy, infrared spectroscopy, microprobe analysis). And also methods of mathematical planning of experiments have been used for the dependence of the physical and technical properties of cements and the directions of their structure formation. Also, the research has been carried out based on the analysis of world achievements in solving the problem of alkaline corrosion of concrete. The possibility of joint operation of the matrix of alkaline cements and active aggregates, represented by basalt, has been determined. The component composition of alkaline cement has been optimized and the need to increase the amount of the alkaline component in the system for the normal course of structure formation processes has been proved. The study of the influence of technical factors and conditions of hardening on the development of processes of structure formation of the investigated compositions has been carried out. The deformation properties of fine-grained concrete based on slag-alkaline cement and basalt aggregate have been investigated. It is shown that the expansion deformations of the samples, which accompany the process of alkaline corrosion of the aggregate in concrete, are directly related to the component composition and hardening conditions of the material. The obtained research results confirm the possibility of using active aggregates for the manufacture of building materials, in particular, based on alkaline cements. But for the safe course of the processes of structure formation, the component composition of the system has to be adjusted by introducing an active mineral additive and an additional alkaline component. The use of hydrophobizing additives makes it possible to increase the strength of the material even when operating under normal heat and humidity conditions.


2021 ◽  
Vol 12 (2) ◽  
pp. 1
Author(s):  
Ji Huilong ◽  
Gao Xin ◽  
WU Wenxuan ◽  
Ma Zhuang ◽  
Qing Qing

In this study, we successfully isolated a strain of Aspergillus oryzae TR08, which produced xylanase secreted to the outside of the cell productively. The enzyme activity and specific activity in the fermentation broth of this strain reached peak values of 451 IU/mL and 1963 IU/mg after 156 h of fermentation. A single factor experiment was designed, and it was found that the strain was adjusted to the initial pH of the fermentation broth to 7.5 in a shaker at 180 rpm and 32 °C. After 156 h of fermentation, the enzyme activity reached a maximum of 1264 IU/mL. The optimal reaction temperature and pH value of the xylanase were 55 °C and 7.5, respectively, and it had excellent acid and alkali resistance and a wide pH activity range. The xylanase was increased the catalytic activity by 15% in 0.25 mM Fe3+, and the biological activity of the enzyme was not affected in the sodium dodecyl sulfate environment.


RSC Advances ◽  
2020 ◽  
Vol 10 (51) ◽  
pp. 30443-30450
Author(s):  
Qilong Sun ◽  
Yue Ji ◽  
LiFen He ◽  
Xiaoyun Long

Carbon fiber is an absorbing material with high strength, acid and alkali resistance, high temperature resistance, flexibility, and processability and plays an important role in the electromagnetic (EM) wave absorption of civil buildings and military equipment.


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