Studies on Acrylonitrile-Butadiene (NBR) Latex-Reinforced Jute Nonwoven Fabric Composites: Chemical Resistance, Mechanical Properties, and Water Absorption

This work reports on the incorporation of Flint and Kaolin rocks powders in the cement mortar in an attempt to improve its mechanical properties and produce an eco-friendly mortar. Flint and Kaolin powders are prepared by dry mechanical milling. The two powders are added separately to the mortars substituting cement partially. The two powders are found to improve the mechanical properties of the mortars. Hardness and compressive strength are found to increase with the increase of powders constituents in the cement mortars. In addition, the two powders affect water absorption and thermal conductivity of the mortar specimens which are desirable for construction applications. Kaolin is found to have a greater effect on the mechanical properties, water absorption, and thermal conductivity of the mortars than Flint. This behavior is discussed and analyzed based on the compositional and structural properties of the rocks powders.

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Combined effects of ammonium polyphosphate and talc on the fire and mechanical properties of epoxy/glass fabric composites

Composites Part B Engineering ◽

10.1016/j.compositesb.2017.01.039 ◽

2017 ◽

Vol 113 ◽

pp. 381-390 ◽

Cited By ~ 36

Author(s):

Mohammad Rajaei ◽

De-Yi Wang ◽

Debes Bhattacharyya

Keyword(s):

Mechanical Properties ◽

Ammonium Polyphosphate ◽

Glass Fabric ◽

Combined Effects ◽

Fabric Composites

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Coatings with recycled polyvinyl butyral on polyester and polyamide mono- and multifilament yarns

Journal of Coatings Technology and Research ◽

10.1007/s11998-020-00445-x ◽

2021 ◽

Author(s):

Rike Brendgen ◽

Carsten Graßmann ◽

Thomas Grethe ◽

Boris Mahltig ◽

Anne Schwarz-Pfeiffer

Keyword(s):

Mechanical Properties ◽

Chemical Resistance ◽

Crosslinking Agent ◽

Polyvinyl Butyral ◽

Polymer Dispersion ◽

Safety Glass ◽

Enhanced Properties ◽

Multifilament Yarns ◽

Textile Coating ◽

Recycled Material

AbstractPolyvinyl butyral is used in safety glass interlayers, mainly in car windshields. Legislative regulations require a recycling of cars after their lifetime and therefore also their safety glass. This causes the availability of recycled polyvinyl butyrate (r-PVB) originated from safety glass interlayers. Due to deteriorated optical properties, such as the transparency, and unknown amounts of plasticizers, it is challenging to reuse the recycled material in new windshields. Therefore, it is of particular interest to find new fields of application for r-PVB, such as the usage as a textile coating. In this research, r-PVB was investigated as a material for yarn coating. Polyester and polyamide mono- and multifilament yarns were coated continuously with solely a polymer dispersion and with mixtures of crosslinking agent and polymer dispersion. Crosslinked r-PVB coatings showed enhanced properties toward abrasion and chemical resistance. Coatings without the crosslinking agent showed a diminished abrasion resistance and could be washed off with ethanol. Mechanical properties of the monofilaments were influenced by the r-PVB coating in general. However, varying concentrations of the crosslinking agent did not affect the mechanical properties.

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Effects of Different Types of Fibers on the Physical and Mechanical Properties of MICP-Treated Calcareous Sand

Materials ◽

10.3390/ma14020268 ◽

2021 ◽

Vol 14 (2) ◽

pp. 268

Author(s):

Jitong Zhao ◽

Huawei Tong ◽

Yi Shan ◽

Jie Yuan ◽

Qiuwang Peng ◽

...

Keyword(s):

Mechanical Properties ◽

Water Absorption ◽

Glass Fiber ◽

Physical And Mechanical Properties ◽

Polyester Fiber ◽

Engineering Properties ◽

Fiber Types ◽

Calcite Precipitation ◽

Calcareous Sand ◽

Hemp Fiber

Microbial-induced calcite precipitation (MICP) has been a promising method to improve geotechnical engineering properties through the precipitation of calcium carbonate (CaCO3) on the contact and surface of soil particles in recent years. In the present experiment, water absorption and unconfined compressive strength (UCS) tests were carried out to investigate the effects of three different fiber types (glass fiber, polyester fiber, and hemp fiber) on the physical and mechanical properties of MICP-treated calcareous sand. The fibers used were at 0%, 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35%, and 0.40% relative to the weight of the sand. The results showed that the failure strain and ductility of the samples could be improved by adding fibers. Compared to biocemented sand (BS), the water absorption of these three fiber-reinforced biocemented sands were, respectively, decreased by 11.60%, 21.18%, and 7.29%. UCS was, respectively, increased by 24.20%, 60.76%, and 6.40%. Polyester fiber produced the best effect, followed by glass fiber and hemp fiber. The optimum contents of glass fiber and polyester fiber were 0.20% and 0.25%, respectively. The optimum content of hemp fiber was within the range of 0.20–0.25%. Light-emitting diode (LED) microscope and scanning electron microscope (SEM) images lead to the conclusion that only a little calcite precipitation had occurred around the hemp fiber, leading to a poor bonding effect compared to the glass and polyester fibers. It was therefore suggested that polyester fiber should be used to improve the properties of biocemented sand.

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Rational Design of Ag/ZnO Hybrid Nanoparticles on Sericin/Agarose Composite Film for Enhanced Antimicrobial Applications

International Journal of Molecular Sciences ◽

10.3390/ijms22010105 ◽

2020 ◽

Vol 22 (1) ◽

pp. 105

Author(s):

Wanting Li ◽

Zixuan Huang ◽

Rui Cai ◽

Wan Yang ◽

Huawei He ◽

...

Keyword(s):

Mechanical Properties ◽

Antimicrobial Activity ◽

Composite Film ◽

Water Absorption ◽

Rational Design ◽

Hybrid Nanoparticles ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

X Ray

Silver-based hybrid nanomaterials are receiving increasing attention as potential alternatives for traditional antimicrobial agents. Here, we proposed a simple and eco-friendly strategy to efficiently assemble zinc oxide nanoparticles (ZnO) and silver nanoparticles (AgNPs) on sericin-agarose composite film to impart superior antimicrobial activity. Based on a layer-by-layer self-assembly strategy, AgNPs and ZnO were immobilized on sericin-agarose films using the adhesion property of polydopamine. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray powder diffraction spectroscopy were used to show the morphology of AgNPs and ZnO on the surface of the composite film and analyze the composition and structure of AgNPs and ZnO, respectively. Water contact angle, swelling ratio, and mechanical property were determined to characterize the hydrophilicity, water absorption ability, and mechanical properties of the composite films. In addition, the antibacterial activity of the composite film was evaluated against Gram-positive and Gram-negative bacteria. The results showed that the composite film not only has desirable hydrophilicity, high water absorption ability, and favorable mechanical properties but also exhibits excellent antimicrobial activity against both Gram-positive and Gram-negative bacteria. It has shown great potential as a novel antimicrobial biomaterial for wound dressing, artificial skin, and tissue engineering.

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The Potential for Natural Stones from Northeastern Brazil to Be Used in Civil Construction

Minerals ◽

10.3390/min11050440 ◽

2021 ◽

Vol 11 (5) ◽

pp. 440

Author(s):

Fabiana Pereira da Costa ◽

Jucielle Veras Fernandes ◽

Luiz Ronaldo Lisboa de Melo ◽

Alisson Mendes Rodrigues ◽

Romualdo Rodrigues Menezes ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Analysis ◽

Differential Thermal Analysis ◽

Chemical Resistance ◽

Mechanical Analysis ◽

Northeastern Brazil ◽

X Ray Diffraction ◽

X Ray ◽

Chemical Agents ◽

Natural Stones

Natural stones (limestones, granites, and marble) from mines located in northeastern Brazil were investigated to discover their potential for use in civil construction. The natural stones were characterized by chemical analysis, X-ray diffraction, differential thermal analysis, and optical microscopy. The physical-mechanical properties (apparent density, porosity, water absorption, compressive and flexural strength, impact, and abrasion) and chemical resistance properties were also evaluated. The results of the physical-mechanical analysis indicated that the natural stones investigated have the potential to be used in different environments (interior, exterior), taking into account factors such as people’s circulation and exposure to chemical agents.

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Effect of Water Ingress on the Mechanical and Chemical Properties of Polybutylene Terephthalate Reinforced with Glass Fibers

Materials ◽

10.3390/ma14051261 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1261

Author(s):

Catarina S. P. Borges ◽

Alireza Akhavan-Safar ◽

Eduardo A. S. Marques ◽

Ricardo J. C. Carbas ◽

Christoph Ueffing ◽

...

Keyword(s):

Mechanical Properties ◽

Water Absorption ◽

Water Uptake ◽

Significant Influence ◽

Water Immersion ◽

Water Diffusion ◽

Polybutylene Terephthalate ◽

Chemical Changes ◽

Water Ingress ◽

Effect Of Water

Short fiber reinforced polymers are widely used in the construction of electronic housings, where they are often exposed to harsh environmental conditions. The main purpose of this work is the in-depth study and characterization of the water uptake behavior of PBT-GF30 (polybutylene terephthalate with 30% of short glass fiber)as well as its consequent effect on the mechanical properties of the material. Further analysis was conducted to determine at which temperature range PBT-GF30 starts experiencing chemical changes. The influence of testing procedures and conditions on the evaluation of these effects was analyzed, also drawing comparisons with previous studies. The water absorption behavior was studied through gravimetric tests at 35, 70, and 130 °C. Fiber-free PBT was also studied at 35 °C for comparison purposes. The effect of water and temperature on the mechanical properties was analyzed through bulk tensile tests. The material was tested for the three temperatures in the as-supplied state (without drying or aging). Afterwards, PBT-GF30 was tested at room temperature following water immersion at the three temperatures. Chemical changes in the material were also analyzed through Fourier-transform infrared spectroscopy (FTIR). It was concluded that the water diffusion behavior is Fickian and that PBT absorbs more water than PBT-GF30 but at a slightly higher rate. However, temperature was found to have a more significant influence on the rate of water diffusion of PBT-GF30 than fiber content did. Temperature has a significant influence on the mechanical properties of the material. Humidity contributes to a slight drop in stiffness and strength, not showing a clear dependence on water uptake. This decrease in mechanical properties occurs due to the relaxation of the polymeric chain promoted by water ingress. Between 80 and 85 °C, after water immersion, the FTIR profile of the material changes, which suggests chemical changes in the PBT. The water absorption was simulated through heat transfer analogy with good results. From the developed numerical simulation, the minimum plate size to maintain the water ingress unidirectional was 30 mm, which was validated experimentally.

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