Preparation and characterization of straw/magnesium cement composites with high-strength and fire-retardant

This research emphasizes the importance of the acid cleaning prior to the phosphate development on high-strength steel rods. It compares the phosphate properties achieved after different acid-pickling conditions. The most common inorganic acids were considered in this study. Additionally, taking into account the environmental and safety concerns of these acids, the assessment of a less harmful organic acid is presented. This study revealed significant differences in the coating morphology and chemical composition whereas no great changes were found in terms of the coating weight or porosity. Thus, hydrochloric and sulfuric acid promote the growth of a Fe-enriched phosphate layer with a less conductive character that is not developed after the pickling with phosphoric acid. The phosphate developed after the citric acid pickling is comparable to that developed after the inorganic acids although with a porosity slightly higher. The temperature of the citric acid bath is an important parameter that affects to the phosphate appearance, composition, and porosity.

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Preparation and characterization of high strength and high modulus PVA fiber via dry‐wet spinning with cross‐linking of boric acid

Journal of Applied Polymer Science ◽

10.1002/app.51394 ◽

2021 ◽

pp. 51394

Author(s):

Xinqiu Hong ◽

Junwei He ◽

Liming Zou ◽

Yanli Wang ◽

Yan Vivian Li

Keyword(s):

Boric Acid ◽

High Strength ◽

Wet Spinning ◽

Cross Linking ◽

High Modulus ◽

Pva Fiber

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Facile Synthesis and Characterization of Palm CNF-ZnO Nanocomposites with Antibacterial and Reinforcing Properties

International Journal of Molecular Sciences ◽

10.3390/ijms22115781 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5781

Author(s):

Janarthanan Supramaniam ◽

Darren Yi Sern Low ◽

See Kiat Wong ◽

Loh Teng Hern Tan ◽

Bey Fen Leo ◽

...

Keyword(s):

Plant Biomass ◽

Cellulose Nanofibers ◽

High Strength ◽

Salmonella Typhi ◽

Particle Sizes ◽

Mechanical Reinforcement ◽

Uniform Size ◽

Preparation Methods ◽

Potential Applications

Cellulose nanofibers (CNF) isolated from plant biomass have attracted considerable interests in polymer engineering. The limitations associated with CNF-based nanocomposites are often linked to the time-consuming preparation methods and lack of desired surface functionalities. Herein, we demonstrate the feasibility of preparing a multifunctional CNF-zinc oxide (CNF-ZnO) nanocomposite with dual antibacterial and reinforcing properties via a facile and efficient ultrasound route. We characterized and examined the antibacterial and mechanical reinforcement performances of our ultrasonically induced nanocomposite. Based on our electron microscopy analyses, the ZnO deposited onto the nanofibrous network had a flake-like morphology with particle sizes ranging between 21 to 34 nm. pH levels between 8–10 led to the formation of ultrafine ZnO particles with a uniform size distribution. The resultant CNF-ZnO composite showed improved thermal stability compared to pure CNF. The composite showed potent inhibitory activities against Gram-positive (methicillin-resistant Staphylococcus aureus (MRSA)) and Gram-negative Salmonella typhi (S. typhi) bacteria. A CNF-ZnO-reinforced natural rubber (NR/CNF-ZnO) composite film, which was produced via latex mixing and casting methods, exhibited up to 42% improvement in tensile strength compared with the neat NR. The findings of this study suggest that ultrasonically-synthesized palm CNF-ZnO nanocomposites could find potential applications in the biomedical field and in the development of high strength rubber composites.

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Preparation and characterization of double network hydrogel with high-strength and self-healing

Materials Today Communications ◽

10.1016/j.mtcomm.2021.102450 ◽

2021 ◽

pp. 102450

Author(s):

Shubin Li ◽

Xiao Wang ◽

Jiang Zhu ◽

Zhenyu Wang ◽

Lu Wang

Keyword(s):

High Strength ◽

Self Healing ◽

Double Network

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Synthesis and characterization of SiO2-TiO2 nanoparticles and their effect on the strength of self-cleaning cement composites

Construction and Building Materials ◽

10.1016/j.conbuildmat.2021.122769 ◽

2021 ◽

Vol 283 ◽

pp. 122769

Author(s):

E.A. Shchelokova ◽

V.V. Tyukavkina ◽

A.V. Tsyryatyeva ◽

A.G. Kasikov

Keyword(s):

Tio2 Nanoparticles ◽

Synthesis And Characterization ◽

Cement Composites ◽

Self Cleaning

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The Influence of Cement Substitution by Biomass Fly Ash on the Polymer–Cement Composites Properties

Materials ◽

10.3390/ma14113079 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3079

Author(s):

Beata Jaworska ◽

Dominika Stańczak ◽

Joanna Tarańska ◽

Jerzy Jaworski

Keyword(s):

Fly Ash ◽

Building Materials ◽

Raw Materials ◽

Combustion Process ◽

Biomass Combustion ◽

Cement Composites ◽

Cement Mortars ◽

Mineral Additive ◽

Biomass Fly Ash

The generation of energy for the needs of the population is currently a problem. In consideration of that, the biomass combustion process has started to be implemented as a new source of energy. The dynamic increase in the use of biomass for energy generation also resulted in the formation of waste in the form of fly ash. This paper presents an efficient way to manage this troublesome material in the polymer–cement composites (PCC), which have investigated to a lesser extent. The research outlined in this article consists of the characterization of biomass fly ash (BFA) as well as PCC containing this waste. The characteristics of PCC with BFA after 3, 7, 14, and 28 days of curing were analyzed. Our main findings are that biomass fly ash is suitable as a mineral additive in polymer–cement composites. The most interesting result is that the addition of biomass fly ash did not affect the rheological properties of the polymer–cement mortars, but it especially influenced its compressive strength. Most importantly, our findings can help prevent this byproduct from being placed in landfills, prevent the mining of new raw materials, and promote the manufacture of durable building materials.

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