Compression and morphological properties of a bio-based polyurethane foam with aluminum hydroxide

Compression and morphological evaluation of a new bio-based polyurethane foam (PUF) with aluminum hydroxide (ATH) added as flame retardant were carried out. The PUF was obtained from a blend of vegetable oils. Compression behavior of the polyurethane with different mass fractions of flame retardant (ATH) was investigated according to ASTM D1621–16. The ATH addition highly increased the compression yield strength of the specimens, going from 0.85 MPa (no ATH) to 2.34 MPa ( + 50%wt ATH). The compression yield strain did not show a noteworthy difference up to 40% ATH, presenting a significant decrement in the PUF + 50%ATH. The compression elasticity modulus increased from 15.40 MPa (no ATH) up to 139.77 MPa ( + 50%wt ATH). SEM images were used in order to evaluate the morphological structure of the foam. Regarding the cell sizes, there was no pattern observed, therefore, the cell sizes were adopted as random. The shapes of the cells were detected as elliptical in two different directions in the same cross-sectional area. The digital image correlation (DIC) technique showed higher strain values where the transverse ellipsoid-shaped cells were located, therefore, the load-oriented ellipsoids presented higher stiffness. Thus, the results for PUF with addition of ATH show that the bio-based material presented an important improvement in the compression properties, which allows this material to become more useful for different applications, such as furniture, building and automobile industries, as well as sandwich structures.

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Synergism between Flame Retardant and Phosphonium Salt Modified Layered Silicate on Properties of Rigid Polyurethane Foam Nanocomposite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.501.8 ◽

2012 ◽

Vol 501 ◽

pp. 8-12 ◽

Cited By ~ 3

Author(s):

Soo Kai Wai ◽

Ahmad Haji Sahrim ◽

Syazana Ahmad Zubir

Keyword(s):

Flame Retardant ◽

Polyurethane Foam ◽

Phosphonium Salt ◽

Test Procedure ◽

Fire Retardant ◽

Layered Silicate ◽

Weight Percentage ◽

Combustion Enthalpy ◽

Compression Properties ◽

Synergistic Mechanism

The current research was conducted to study the incorporation of phosphorus-based flame retardant (exolit OP 1230) and phosphonium salt treated montmorillonite (P-MMT) into polyol resin of polyurethane foam, with the purpose of imparting its compression properties and flammability resistance. To prepare the hybrid composite with a 2.5 wt% based on weight percentage of the overall weight of the system, fractions of exolit OP 1230 are mixed with P-MMT following a percentage ratio of 25/75, 50/50 and 75/25. The result of the mechanical property testing showed that the compression strength of composite was decreased with the presence of exolit OP 1230. However, the result obtained also demonstrated that the fire behaviour of the foam was improved. The study indicated that a combination of exolite OP 1230 and P-MMT generates a synergistic mechanism effect which could be used as an effective fire retardant as compared to sample with a 2.5% P-MMT alone. On the other hand, horizontal burning test following an ASTM D635 test procedure was conducted to determine the burning rate and bomb calorimeter model Ika C5003 was employed to detect the combustion enthalpy in this study. Finally, the findings of the analysis of the mechanical properties were further supported by the SEM micrographs.

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Effect of nanosilica and aluminum hydroxide on thermal, flammability, and morphology properties of nanocomposite made of recycled high-density polyethylene and OCC flour

BioResources ◽

10.15376/biores.15.2.3382-3393 ◽

2020 ◽

Vol 15 (2) ◽

pp. 3382-3393

Author(s):

Ahmad Samariha ◽

Behzad Bazyar

Keyword(s):

Aluminum Hydroxide ◽

High Density Polyethylene ◽

Morphological Characteristics ◽

High Density ◽

Constant Level ◽

Morphological Properties ◽

Connection Matrix ◽

Sem Images ◽

X Ray ◽

Twin Screw Extruders

Effects of nanosilica and aluminum hydroxide were considered relative to thermal, flammability, and morphological properties of nanocomposites from recycled high-density polyethylene (rHDPE) and old corrugated container (OCC) pulp. Amounts of 50% recycled high-density polyethylene and 50% OCC flour were used. The nanosilica was used at three weight levels of 0%, 5%, and 10%. Lastly, aluminum hydroxide at a constant level of 5% and maleic anhydride grafted polyethylene at a constant level of 3% were mixed by twin screw extruders. The samples were made using a hand-press. The thermal and flammability properties were then measured. To consider the structure and function of nanosilica, the morphological characteristics of wood-plastic composites (WPC) were studied by X-ray diffractograms (XRD) and scanning electron microscopy (SEM) analyses. The results showed that increasing the nanosilica content up to 10% increased the thermal stability, and more charcoal was retained. Moreover, the limited oxygen index increased. X-ray diffractograms showed that the width and peak intensity decreased with the increased intake of silica nanoparticles. The SEM images showed that more adaptability was achieved through increasing the amount of nanosilica. Additionally, better and more homogenous bonds were observed between the fibers and connection matrix, and fewer gaps and pores were observed.

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Effect of SWCNT Filler on Mechanical Properties and Electrical Conductivity of PVA/CS/GA/SWCNT Nanocomposite Thin Film

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.840.441 ◽

2020 ◽

Vol 840 ◽

pp. 441-447 ◽

Cited By ~ 1

Author(s):

Fitri Khoerunnisa ◽

Esti Septiani ◽

Hendrawan Hendrawan ◽

Yaya Sonjaya

Keyword(s):

Thin Film ◽

Thin Films ◽

Mechanical Properties ◽

Electrical Conductivity ◽

Tensile Strength ◽

Morphological Structure ◽

X Ray Diffraction ◽

Sem Images ◽

Cross Sectional ◽

Conductive Thin Films

This study aims to investigate the effect of SWCNT nanofiller on mechanical properties and electrical conductivity of PVA/CS/GA nanocomposite film. Polyvinyl alcohol (PVA) and chitosan (CS) are used as polymer matrix that crosslinked by glutaraldehyde (GA). Nanofiller SWCNT was inserted in a polymer composite matrix at different composition. The thin films were characterized using FTIR (Fourier Transform Infrared Spectroscopy), XRD (X-ray diffraction), SEM (Scanning Electron Microscopy), TG/DTA (Thermal Gravimetric/Differential Thermal Analysis), sheet resistance, and tensile strength measurements. The results revealed that the addition of SWCNT notably increased the electrical conductivity of composite film from 1.2 x 10‒4 S.cm‒1 to 9 x10‒3 S cm‒1 as well as tensile strength and elongation 43 MPa to 62 MPa, 68% to 84%, respectively. The cross-sectional SEM images indicated that the conductive thin films have a layered structure where the insertion of SWCNT did not change their morphological structure significantly. Additionally, SWCNT improved the thermal stability of PVA/CS/GA nanocomposites thin film. These finding can be promising for the development of optoelectronic devices i.e. photovoltaic, emitting diodes, etc.

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Mechanical and Flammability Properties of Green Polyurethane Foam with Alumina Trihydrate as Flame Retardant

10.26678/abcm.cobem2017.cob17-2180 ◽

2017 ◽

Author(s):

Amanda Silva ◽

Enio Henrique Pires da Silva ◽

Danilo Janes ◽

Romeu Rony Cavalcante da Costa ◽

Giovanna Gabriela Crem Silva

Keyword(s):

Flame Retardant ◽

Polyurethane Foam ◽

Alumina Trihydrate

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Synergistic Flame Retardant Effect of Organic Boron Flame Retardant and Aluminum Hydroxide on Polyethylene

Fibers and Polymers ◽

10.1007/s12221-021-9385-6 ◽

2021 ◽

Vol 22 (2) ◽

pp. 354-365

Author(s):

Lianghui Ai ◽

Shanshan Chen ◽

Liu Yang ◽

Ping Liu

Keyword(s):

Flame Retardant ◽

Aluminum Hydroxide ◽

Synergistic Flame Retardant

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Assessment of the Foot’s Longitudinal Arch by Different Indicators and Their Correlation with the Foot Loading Paradigm in School-Aged Children: A Cross Sectional Study

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18105196 ◽

2021 ◽

Vol 18 (10) ◽

pp. 5196

Author(s):

Beata Szczepanowska-Wołowiec ◽

Paulina Sztandera ◽

Ireneusz Kotela ◽

Marek Zak

Keyword(s):

Morphological Structure ◽

Cross Sectional Study ◽

Strongly Correlated ◽

Cross Sectional ◽

School Aged Children ◽

Longitudinal Arch ◽

Flat Feet ◽

Foot Loading ◽

Static Conditions ◽

Increased Pressure

Background: There are numerous studies assessing the morphological structure of the foot, but there is a notable scarcity of those focused on juxtaposing various longitudinal arch indices with foot loading paradigm. The present study aimed to determine the overall reliability, diagnostic accuracy of respective variables, and their correlation with the foot loading paradigm. Methods: The study group consisted of 336 children, aged 10–15 years (girls 49.1% and boys 50.9%). The morphological structure of the plantar part of the foot in static conditions was assessed with the aid of a 2D podoscan. Individual foot loading paradigm in static conditions was assessed making use of the FreeMed platform. Results: Staheli (SI), Chippaux–Smirak (CSI), and Sztriter–Godunow (KY) indices were strongly correlated with each other (ρ > 0.84, p < 0.001). Own research corroborated an increased pressure of hollow feet, as assessed by the SI, CSI, and KY indices, on the forefoot and the hindfoot, foot zones B, E, F; these correlations being statistically significant. The results yielded by the present study also indicate an increased pressure on the metatarsal, and foot zones C, D of the flat feet. Conclusions: Flatfootedness is not believed to be a common deformity among children and adolescents. The SI, CSI, and KY indices were found to be strongly correlated, as well as proved reliable in assessing the foot’s longitudinal arch.

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Yeast Morphology Assessment through Automated Image Analysis during Fermentation

Fermentation ◽

10.3390/fermentation7020044 ◽

2021 ◽

Vol 7 (2) ◽

pp. 44

Author(s):

Mario Guadalupe-Daqui ◽

Mandi Chen ◽

Katherine A. Thompson-Witrick ◽

Andrew J. MacIntosh

Keyword(s):

Image Analysis ◽

High Stress ◽

Cross Sectional Area ◽

Automated Image Analysis ◽

Yeast Cells ◽

Morphological Properties ◽

Cell Area ◽

Sectional Area ◽

Cross Sectional ◽

Industrial Fermentation

The kinetics and success of an industrial fermentation are dependent upon the health of the microorganism(s) responsible. Saccharomyces sp. are the most commonly used organisms in food and beverage production; consequently, many metrics of yeast health and stress have been previously correlated with morphological changes to fermentations kinetics. Many researchers and industries use machine vision to count yeast and assess health through dyes and image analysis. This study assessed known physical differences through automated image analysis taken throughout ongoing high stress fermentations at various temperatures (30 °C and 35 °C). Measured parameters included sugar consumption rate, number of yeast cells in suspension, yeast cross-sectional area, and vacuole cross-sectional area. The cell morphological properties were analyzed automatically using ImageJ software and validated using manual assessment. It was found that there were significant changes in cell area and ratio of vacuole to cell area over the fermentation. These changes were temperature dependent. The changes in morphology have implications for rates of cellular reactions and efficiency within industrial fermentation processes. The use of automated image analysis to quantify these parameters is possible using currently available systems and will provide additional tools to enhance our understanding of the fermentation process.

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