FIRE HAZARD AND PHYSICO-MECHANICAL PROPERTIES FOR EPOXY-AMINE COMPOSITES CONTAINING THE [Cu(DETA)(H2O)]SO4·H2O FLAME RETARDANT-HARDENER

Introduction. The rapid growth of production rates and the use of polymer materials in various fields has brought about an increase in the number of fires caused by the ignition of polymer products. Among the most common polymer materials are materials based on epoxy resins. They are used in such industries as construction, electrical engineering and radio engineering, shipbuilding, mechanical engineering, including automotive, aerospace and rocketry, etc. Due to its organic structure, high content of carbon and hydrogen, epoxy polymers are very combustible. Their combustion is characterized by high temperature and more flame propagation rate. And it is accompanied by significant smoke formation and the release of large amounts of toxic products. Therefore, the search for new ways to reduce combustibility and maintain the proper level of performance is one of the priorities in the development and implementation of new epoxy polymer materials in various fields. Purpose. The work aims to obtain epoxy-amine composites and to discover the effect of flame retardant-hardener on their fire hazard and physical and mechanical properties.Methods. In work used Modern research methods. The flame propagation rate was determined by UL94, the coefficient of smoke was measured by ASTM E662-19, physical and mechanical properties were evaluated by measuring parameters such as surface hardness, tensile strength, water absorption and chemical resistance.Results. The parameters of fire danger of epoxy-amine composites with different content of flame retardant (0, 5, 16 and 80 mass parts) were studied. The results of experimental studies showed that the flame propagation rate and the smoke formation coefficient in the mode of smouldering and combustion are minimal for epoxy-amine composites containing 16 and 80 mass parts of flame retardant. Such compositions have higher surface hardness and tensile strength. And they also well as more resistant to water and aggressive environments compared to unmodified ones.Conclusion. The paper presents a simple and commercially attractive method of obtaining epoxy-amine composites con-taining different amounts of flame retardant – copper(II) sulfate. It is necessary, the obtained samples of the composites are homogeneous in structure. These should be considered as individual chemicals, not as mixtures. Chemical bonding of all components of the composites, namely the appearance of additional (compared to the unmodified composite) Cu(II)–N coordination bonds in the polymer framework DGEBA/DETA-CuSO4, is reflected in the enhanced physical and mechanical properties and fire hazard reduction for this type of composite materials.

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Physico-mechanical properties of cattle hide leather for working gloves with flame retardant addition

Livestock and Animal Research ◽

10.20961/lar.v18i2.42937 ◽

2020 ◽

Vol 18 (2) ◽

pp. 151

Author(s):

Iwan Fajar Pahlawan ◽

Gresy Griyanitasari

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Flame Retardant ◽

Descriptive Analysis ◽

Physical And Mechanical Properties ◽

Metal Casting ◽

Protective Equipment ◽

Elongation At Break ◽

Finishing Process ◽

Casting Industry

Objective: Indonesian metal casting industry is a labor-oriented industry which involves thermal application in the workplace. Thus, it is essential to protect the workers for any risks during their activity. Leather gloves, as personal protective equipment, need to be manufactured that can prevent the workers from burn injured. The study aimed to analyze the effect of flame retardant addition on finished leather’s physical and mechanical properties for a specific article, i.e. working gloves.Methods: The research used pickled cattle hides and commercial flame retardant as main materials. The leather chemicals used in the process are those which is commonly used to manufacture working gloves leather article. The treatments involved the addition of commercial flame retardant in fatliquoring (2%, 4%, 6% w/w) and finishing process (100 parts, 200 parts, 300 parts). The effect of flame retardant addition on shrinkage percentage, thickness, rub fastness, tensile strength, and elongation at break, were evaluated. Descriptive analysis is applied to describe the properties of the resulted finished leather.Results: The result shows that the addition of flame retardant in fatliquoring and finishing process indicates a variation in the leather’s physical-mechanical properties. The leather, manufactured with the addition of 4% (w/w) in fatliquoring, shrunk 7.65±1.42%, had tensile strength value at 520.48±13.79 kg/cm2, good rub fastness at dry and wet basis (5 and 4/5), elongation value at 52.9±4.09%, and thickness 0.87±0.02 mm.Conclusions: it can be concluded that the use of 4% (w/w) flame retardant in fatliquoring is suggested to be the best formulation to produce working gloves leather.

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Improving the surface quality and mechanical properties of selective laser sintered PA2200 components by the vibratory surface finishing process

SN Applied Sciences ◽

10.1007/s42452-021-04371-4 ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Hamaid M. Khan ◽

Tolga B. Sirin ◽

Gurkan Tarakci ◽

Mustafa E. Bulduk ◽

Mert Coskun ◽

...

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Tensile Strength ◽

Additive Manufacturing ◽

Microstructural Analysis ◽

Surface Hardness ◽

Physical And Mechanical Properties ◽

Surface Finishing ◽

Finishing Process ◽

Wide Range

Abstract This paper attempts to improve the physical and mechanical properties of selective laser sintered polyamide PA2200 components through a vibratory surface finishing process by inducing severe plastic deformation at the outer surface layers. The industrial target of additive manufacturing components is to obtain structures having surface roughness, hardness, and other mechanical properties equivalent to or better than those produced conventionally. Compared to the as-built SLS PA2200 samples, vibratory surface finishing treated specimens exhibited a smooth surface microstructure and more favorable roughness, hardness, and tensile strength. Also, the duration of the vibratory surface finishing process showed a further improvement in the surface roughness and hardness of the SLS samples. Compared to the as-built state, the roughness and hardness of the surface-treated samples improved by almost 90% and 15%, respectively. Consequently, microstructural analysis indicates that lower surface roughness and enhanced surface hardness is a crucial factor in influencing the overall tensile strength of SLS-PA2200 components. We consider that the combination of VSF and SLS processes can successfully handle a wide range of potential applications. This study also highlights the efficiency and applicability of the vibratory surface finishing process to other additive manufacturing processes and materials. Graphic abstract

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Substantiation of Polymer Materials for the Use in Plow Constructions

Central Ukrainian Scientific Bulletin. Technical Sciences ◽

10.32515/2664-262x.2020.3(34).102-107 ◽

2020 ◽

pp. 102-107

Author(s):

Oleksii Derkach ◽

◽

Oleh Kabat ◽

Dmytro Makarenko ◽

Borys Kharchenko ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Composite Material ◽

Polymer Composite ◽

Physical And Mechanical Properties ◽

Polymer Composite Material ◽

Polymer Materials ◽

Initial Sample ◽

Pyrolytic Decomposition ◽

Initial Sample Weight

The purpose of the work is to study and determine material "TEKRONE" belonging to the group of polymers, substantiate such a polymer composite material (PCM) in the modernization of the plow blade, which is not inferior to the "TEKRONE" composite and is much cheaper. This requires the study of the physical and mechanical properties of the material. The following studies of the physical and mechanical properties of the "TEKRONE" material have been conducted: density, heat endurance, and tensile strength. It has been found out that when heated over an open flame, the polymer softens with subsequent melting. There is no charring, destruction in the solid state. Therefore, the TEKRONE material is a thermoplastic. After pyrolytic decomposition 0.5… 0.7% of the initial sample weight remains. PCM TEKRONE density is 954 kg/m3. The value of this parameter coincides with the polyethylene density, which, depending on the brand, varies from 910 to 980 kg/m3. The tensile strength stress of the investigated samples of PCM TEKRONE is 17.9 MPa, which is very close to the values of polyethylene (14.8-17.0 MPa). The laboratory studies have shown that TEKRONE polymer-composite material in its properties corresponds to the materials based on polyethylene. It is determined that the closest in properties are PE 500 and PE 1000 polyethylene. It is advisable to recommend the use of PE 500 and PE 1000 polyethylene as a basis for the manufacture of plow blade of PLN type.

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Effect of silver nitrate on some mechanical properties of heat polymerizing acrylic resins

Mustansiria Dental Journal ◽

10.32828/mdj.v14i1.768 ◽

2019 ◽

Vol 14 (1) ◽

pp. 110

Author(s):

Assiss. Prof. Dr. Sabiha Mahdi Mahdi ◽

Dr. Firas Abd K. Abd K.

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Silver Nitrate ◽

Surface Hardness ◽

Mechanical Tests ◽

Hardness Tester ◽

Acrylic Resins ◽

The Difference

Aim: The aimed study was to evaluate the influence of silver nitrate on surfacehardness and tensile strength of acrylic resins.Materials and methods: A total of 60 specimens were made from heat polymerizingresins. Two mechanical tests were utilized (surface hardness and tensile strength)and 4 experimental groups according to the concentration of silver nitrate used.The specimens without the use of silver nitrate were considered as control. Fortensile strength, all specimens were subjected to force till fracture. For surfacehardness, the specimens were tested via a durometer hardness tester. Allspecimens data were analyzed via ANOVA and Tukey tests.Results: The addition of silver nitrate to acrylic resins reduced significantly thetensile strength. Statistically, highly significant differences were found among allgroups (P≤0.001). Also, the difference between control and experimental groupswas highly significant (P≤0.001). For surface hardness, the silver nitrate improvedthe surface hardness of acrylics. Highly significant differences were statisticallyobserved between control and 900 ppm group (P≤0.001); and among all groups(P≤0.001)with exception that no significant differences between control and150ppm; and between 150ppm and 900ppm groups(P>0.05).Conclusion: The addition of silver nitrate to acrylics reduced significantly the tensilestrength and improved slightly the surface hardness.

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Damage Evolution of Granodiorite after Heating and Cooling Treatments

Minerals ◽

10.3390/min11070779 ◽

2021 ◽

Vol 11 (7) ◽

pp. 779

Author(s):

Mohamed Gomah ◽

Guichen Li ◽

Salah Bader ◽

Mohamed Elkarmoty ◽

Mohamed Ismael

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Failure Mode ◽

Physical And Mechanical Properties ◽

P Wave ◽

Physical Parameters ◽

Slow Cooling ◽

Heating And Cooling ◽

Natural Rock ◽

The Impact

The awareness of the impact of high temperatures on rock properties is essential to the design of deep geotechnical applications. The purpose of this research is to assess the influence of heating and cooling treatments on the physical and mechanical properties of Egyptian granodiorite as a degrading factor. The samples were heated to various temperatures (200, 400, 600, and 800 °C) and then cooled at different rates, either slowly cooled in the oven and air or quickly cooled in water. The porosity, water absorption, P-wave velocity, tensile strength, failure mode, and associated microstructural alterations due to thermal effect have been studied. The study revealed that the granodiorite has a slight drop in tensile strength, up to 400 °C, for slow cooling routes and that most of the physical attributes are comparable to natural rock. Despite this, granodiorite thermal deterioration is substantially higher for quick cooling than for slow cooling. Between 400:600 °C is ‘the transitional stage’, where the physical and mechanical characteristics degraded exponentially for all cooling pathways. Independent of the cooling method, the granodiorite showed a ductile failure mode associated with reduced peak tensile strengths. Additionally, the microstructure altered from predominantly intergranular cracking to more trans-granular cracking at 600 °C. The integrity of the granodiorite structure was compromised at 800 °C, the physical parameters deteriorated, and the rock tensile strength was negligible. In this research, the temperatures of 400, 600, and 800 °C were remarked to be typical of three divergent phases of granodiorite mechanical and physical properties evolution. Furthermore, 400 °C could be considered as the threshold limit for Egyptian granodiorite physical and mechanical properties for typical thermal underground applications.

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Thermal, Physical and Mechanical Properties of Poly(Butylene Succinate)/Kenaf Core Fibers Composites Reinforced with Esterified Lignin

Polymers ◽

10.3390/polym13142359 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2359

Author(s):

Harmaen Ahmad Saffian ◽

Masayuki Yamaguchi ◽

Hidayah Ariffin ◽

Khalina Abdan ◽

Nur Kartinee Kassim ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Loss Modulus ◽

Physical And Mechanical Properties ◽

Weight Percent Gain ◽

Weight Percent ◽

Esterification Reaction ◽

Butylene Succinate ◽

Kenaf Core ◽

Modified Lignin

In this study, Kraft lignin was esterified with phthalic anhydride and was served as reinforcing filler for poly(butylene succinate) (PBS). Composites with different ratios of PBS, lignin (L), modified lignin (ML) and kenaf core fibers (KCF) were fabricated using a compounding method. The fabricated PBS composites and its counterparts were tested for thermal, physical and mechanical properties. Weight percent gain of 4.5% after lignin modification and the FTIR spectra has confirmed the occurrence of an esterification reaction. Better thermo-mechanical properties were observed in the PBS composites reinforced with modified lignin and KCF, as higher storage modulus and loss modulus were recorded using dynamic mechanical analysis. The density of the composites fabricated ranged from 1.26 to 1.43 g/cm3. Water absorption of the composites with the addition of modified lignin is higher than that of composites with unmodified lignin. Pure PBS exhibited the highest tensile strength of 18.62 MPa. Incorporation of lignin and KCF into PBS resulted in different extents of reduction in tensile strength (15.78 to 18.60 MPa). However, PBS composite reinforced with modified lignin exhibited better tensile and flexural strength compared to its unmodified lignin counterpart. PBS composite reinforced with 30 wt% ML and 20 wt% KCF had the highest Izod impact, as fibers could diverge the cracking propagation of the matrix. The thermal conductivity value of the composites ranged from 0.0903 to 0.0983 W/mK, showing great potential as a heat insulator.

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Laboratory Study of Deformation Behaviour of Two New Reinforcing Polymeric TSLs and Their Potential Application in Deep Underground Coal Mine

Polymers ◽

10.3390/polym13132205 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2205

Author(s):

Han Liang ◽

Jun Han ◽

Chen Cao ◽

Shuangwen Ma

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Underground Mining ◽

Deformation Behaviour ◽

Polymer Materials ◽

Surface Protection ◽

Steel Mesh ◽

Geological Conditions ◽

Deep Underground ◽

Roadway Support

Thin spray-on liner (TSL) is a surface protection technology used by spraying a polymer film, which is widely used for mine airtightness and waterproofing. A reinforcing TSL can replace steel mesh, which is a new method for roadway support. This paper reviews the development of a reinforcing TSL. Considering the deterioration of geological conditions in deep underground mining and the demand for reinforcing automation, two kinds of polymeric reinforcing TSL (RPTSL) materials are developed. The mechanical characteristics of the new TSL materials are studied experimentally. Results show that the average compressive strength, tensile strength, cohesion, and internal friction angle of the two TSL materials are 52 and 32 MPa, 12 and 8 MPa, 6.2 and 17.2 MPa, and 33.6° and 25.9°, respectively. The bonding strength between the two materials and coal is greater than the tensile strength of coal itself, and the mechanical properties of the material for comparison are lower than those of both materials. Based on the TSL support mechanism, we examine the application of the two TSL materials to the mining environment and compare the mechanical properties of polymer materials and cement-based materials. The advantages of polymer materials include versatile mechanical properties, good adhesion, and high early strength. This study provides a new support material to replace steel mesh for roadway surface support, which satisfies the needs of different surface support designs under complex geological conditions, and promotes the automation of roadway support.

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Effect of Castor Oil Impregnation on the Physical and Mechanical Properties of Bacterial Cellulose

Polymers from Renewable Resources ◽

10.1177/204124791200300102 ◽

2012 ◽

Vol 3 (1) ◽

pp. 13-26

Author(s):

Myrtha Karina ◽

Lucia Indrarti ◽

Rike Yudianti ◽

Indriyati

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Bacterial Cellulose ◽

Young’S Modulus ◽

Castor Oil ◽

Young's Modulus ◽

Physical And Mechanical Properties ◽

Scanning Electron Micrographs ◽

Elongation At Break ◽

Acetone Water

The effect of castor oil on the physical and mechanical properties of bacterial cellulose is described. Bacterial cellulose (BC) was impregnated with 0.5–2% (w/v) castor oil (CO) in acetone–water, providing BCCO films. Scanning electron micrographs revealed that the castor oil penetrated the pores of the bacterial cellulose, resulting in a smoother morphology and enhanced hydrophilicity. Castor oil caused a slight change in crystallinity indices and resulted in reduced tensile strength and Young's modulus but increased elongation at break. A significant reduction in tensile strength and Young's modulus was achieved in BCCO films with 2% castor oil, and there was an improvement in elongation at break and hydrophilicity. Impregnation with castor oil, a biodegradable and safe plasticiser, resulted in less rigid and more ductile composites.

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Enhancement of Mechanical Properties and Porosity of Concrete Using Steel Slag Coarse Aggregate

Materials ◽

10.3390/ma13122865 ◽

2020 ◽

Vol 13 (12) ◽

pp. 2865

Author(s):

Md Jihad Miah ◽

Md. Munir Hossain Patoary ◽

Suvash Chandra Paul ◽

Adewumi John Babafemi ◽

Biranchi Panda

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Microstructural Analysis ◽

Steel Slag ◽

Physical And Mechanical Properties ◽

Length Change ◽

Sustainable Building ◽

Burnt Clay ◽

Lower Porosity ◽

Furnace Steel

This paper investigates the possibility of utilizing steel slags produced in the steelmaking industry as an alternative to burnt clay brick aggregate (BA) in concrete. Within this context, physical, mechanical (i.e., compressive and splitting tensile strength), length change, and durability (porosity) tests were conducted on concrete made with nine different percentage replacements (0%, 10%, 20%, 30%, 40%, 50%, 60%, 80%, and 100% by volume of BA) of BA by induction of furnace steel slag aggregate (SSA). In addition, the chemical composition of aggregate through X-ray fluorescence (XRF) analysis and microstructural analysis through scanning electron microscopy (SEM) of aggregates and concrete were performed. The experimental results show that the physical and mechanical properties of concrete made with SSA were significantly higher than that of concrete made with BA. The compressive and tensile strength increased by 73% when SSA fully replaced BA. The expansion of concrete made with SSA was a bit higher than the concrete made with BA. Furthermore, a significant lower porosity was observed for concrete made with SSA than BA, which decreased by 40% for 100% SSA concrete than 100% BA concrete. The relation between compressive and tensile strength with the porosity of concrete mixes are in agreement with the relationships presented in the literature. This study demonstrates that SSA can be used as a full replacement of BA, which is economical, conserves the natural aggregate, and is sustainable building material since burning brick produces a lot of CO2.

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Composites from Thermoplastic Natural Rubber Reinforced Rubberwood Sawdust: Effects of Sawdust Size and Content on Thermal, Physical, and Mechanical Properties

International Journal of Polymer Science ◽

10.1155/2018/7179527 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Chatree Homkhiew ◽

Surasit Rawangwong ◽

Worapong Boonchouytan ◽

Wiriya Thongruang ◽

Thanate Ratanawilai

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Natural Rubber ◽

High Density Polyethylene ◽

High Performance ◽

Physical And Mechanical Properties ◽

Modulus Of Rupture ◽

Shore Hardness ◽

Thermoplastic Natural Rubber ◽

Plastic Content

The aim of this work is to investigate the effects of rubberwood sawdust (RWS) size and content as well as the ratio of natural rubber (NR)/high-density polyethylene (HDPE) blend on properties of RWS reinforced thermoplastic natural rubber (TPNR) composites. The addition of RWS about 30–50 wt% improved the modulus of the rupture and tensile strength of TPNR composites blending with NR/HDPE ratios of 60/40 and 50/50. TPNR composites reinforced with RWS 80 mesh yielded better tensile strength and modulus of rupture than the composites with RWS 40 mesh. The TPNR/RWS composites with larger HDPE content gave higher tensile, flexural, and Shore hardness properties and thermal stability as well as lower water absorption. The TPNR/RWS composites with larger plastic content were therefore suggested for applications requiring high performance of thermal, physical, and mechanical properties.

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