scholarly journals Vacuum-Based Impregnation of Liquid Glass into Sunflower Press Cake Particles and Their Use in Bio-Based Rigid Polyurethane Foam

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5351
Author(s):  
Agnė Kairytė ◽  
Sylwia Członka ◽  
Renata Boris ◽  
Sigitas Vėjelis
Keyword(s):  
Thermal Conductivity ◽  
Thermal Stability ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Water Absorption ◽  
Liquid Glass ◽  
Press Cake ◽  
Short Term ◽  
Average Cell Size ◽  
Average Cell

The study analyses rigid polyurethane (PUR) foam modified with 10–30 wt.% sunflower press cake (SFP) and liquid glass-impregnated sunflower press cake (LG-SFP) particles and their impact on performance characteristics of PUR foams—foaming behaviour, rheology, thermal conductivity, compressive strength parallel and perpendicular to the foaming directions, tensile strength, dimensional stability, short-term water absorption by partial immersion, and thermal stability. Even though the dynamic viscosity and apparent density were increased for SFP and LG-SFP formulations, thermal conductivity values improved by 17% and 10%, respectively, when 30 wt.% of particles were incorporated. The addition of SFP and LG-SFP particles resulted in the formation of more structurally and dimensionally stable PUR foams with a smaller average cell size and a greater content of closed cells. At 30 wt.% of SFP and LG-SFP particles, compressive strength increased by 114% and 46% in the perpendicular direction, respectively, and by 71% and 67% in the parallel direction, respectively, while tensile strength showed an 89% and 85% higher performance at 30 wt.% SFP and LG-SFP particles loading. Furthermore, short-term water absorption for all SFP and LG-SFP modified PUR foam formulations was almost two times lower compared to the control foam. SFP particles reduced the thermal stability of modified PUR foams, but LG-SFP particles shifted the thermal decomposition temperatures towards higher ones.

scholarly journals Evaluation of the Performance of Bio-Based Rigid Polyurethane Foam with High Amounts of Sunflower Press Cake Particles

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5475
Author(s):  
Agnė Kairytė ◽  
Sylwia Członka ◽  
Renata Boris ◽  
Sigitas Vėjelis
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Water Absorption ◽  
Polyurethane Foam ◽  
Mechanical Performance ◽  
Positive Impact ◽  
Press Cake ◽  
Rigid Polyurethane Foam ◽  
Average Cell

In the current study, rigid polyurethane foam (PUR) was modified with 10–30 wt.% sunflower press cake (SFP) filler, and its effect on performance characteristics—i.e., rheology, characteristic foaming times, apparent density, thermal conductivity, compressive strength parallel and perpendicular to the foaming directions, tensile strength, and short-term water absorption by partial immersion—was evaluated. Microstructural and statistical analyses were implemented as well. During the study, it was determined that 10–20 wt.% SFP filler showed the greatest positive impact. For instance, the thermal conductivity value improved by 9% and 17%, respectively, while mechanical performance, i.e., compressive strength, increased by 11% and 28% in the perpendicular direction and by 43% and 67% in the parallel direction. Moreover, tensile strength showed 49% and 61% increments, respectively, at 10 wt.% and 20 wt.% SFP filler. Most importantly, SFP filler-modified PUR foams were characterised by two times lower water absorption values and improved microstructures with a reduced average cell size and increased content in closed cells.

scholarly journals A New Marine Biomaterial: The Shell of Mangrove Horseshoe Crabs, Carcinoscorpius rotundicauda (Latreille, 1802) Emphasizing Its Physico-Chemical Characteristics

2021 ◽  
Vol 8 ◽  
Author(s):  
Yusli Wardiatno ◽  
Bambang Riyanto ◽  
Nopa Aris Iskandar ◽  
Sonja Kleinertz ◽  
Peter Funch ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Water Absorption ◽  
Horseshoe Crab ◽  
Chemical Characteristics ◽  
Gravimetric Analysis ◽  
Physico Chemical ◽  
The Future ◽  
Horseshoe Crabs

The paper aims to elucidate the physico-chemical characteristics of the shell of mangrove horseshoe crabs (Carcinoscorpius rotundicauda) and determine the compilation matrix for the first time. The shell composition matrix of C. rotundicauda has never been studied in detail before, especially the shape of the foam, the chemical composition, the functional groups and the mechanical-physical and thermal properties of the shell. Based on this study, the shell structure of the mangrove horseshoe crab has the potential to be used as the base structure for developing bio-foam insulator material in the future. Therefore, the shell of mangrove horseshoe crabs has a unique natural structure in the form of foam. Its robust and elastic structure has the potential for further development for new marine biomaterials. The formation and composition of horseshoe crab shells foam are also believed to be multifunctional in mobility, used for defense mechanisms and thermal stability. The horseshoe crab samples were collected from Pacitan coastal waters, East Java, Indonesia. The research was conducted using physico-chemical and mechanical-physical analysis. The scanning electron microscopy was used in order to clarify the physico-chemical characteristics. The measurements of the mechanical-physical characteristics included density, unit cell size, and water absorption. The tensile strength and compressive strength were analyzed based on the American Society for Testing Material. Thermal resistance was measured by thermal gravimetric analysis. The results showed that the horseshoe crab shells have a unique structure, where chitin, protein and some minerals are the main chemical elements. The combination and major constituents of the horseshoe crab shell material provide strong and plastic mechanical properties with a maximum tensile strength of 60.46 kPa and maximum compressive strength of 110.55 kPa, water absorption of 0.01195 ± 0.001% and a density value of 0.1545 ± 0.011 g/cm3 as well as the capability to withstand thermal loads with peak decomposition values of 267.4–823.2°C and thermal stability of 60.59%. Using natural marine biomaterials in the future will be beneficial because it leaves no harmful residues and therefore has environmental advantages and at the same time, it is also more cost-effective.

Preparation and properties of melamine-formaldehyde rigid closed-cell foam toughened by ethylene glycol/carbon fiber

2020 ◽  
pp. 026248932092923
Author(s):  
Chunhui Li ◽  
Haihong Ma ◽  
Zhengfa Zhou ◽  
Weibing Xu ◽  
Fengmei Ren ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Thermal Stability ◽  
Compressive Strength ◽  
Water Absorption ◽  
Cellular Structure ◽  
Bending Strength ◽  
Melamine Formaldehyde ◽  
Cell Ratio ◽  
Closed Cell ◽  
Rigid Foams

Toughing melamine-formaldehyde (MF) rigid closed-cell foams were prepared by using ethylene glycol (EG) and carbon fiber (CF) as composite toughening agents. The pulverization rate, compressive strength, bending strength, cellular structure, closed-cell ratio, water absorption ratio, thermal conductivity, thermal stability, limiting oxygen index (LOI), and char yield were characterized to study the morphology, mechanical, thermal, and fire-retardant properties of as-prepared toughing MF rigid foams. The pulverization rate result showed that introduction of composite modifier can obviously improve the toughness of MF rigid foams. The cellular structure, closed-cell ratio, and water absorption results showed that the addition of EG/CF can increase the closed-cell ratio and control the cell size of MF rigid foams. The compressive strength and bending strength results showed that the incorporation of composite modifier of MF rigid foams dramatically improved the mechanical properties. The LOI, char yield, and thermal stability results showed that the toughing MF rigid foams remained more intact char skeleton with flame-retardant effect, thus reducing the fire hazards. The as-prepared toughing MF rigid foams showed the best comprehensive performance with pulverization rate of 5.21%, compressive strength of 355.3 kPa, bending strength of 0.44 MPa, closed-cell ratio of 79.1%, water absorption of 9%, thermal conductivity of 0.031 W m−1 K−1, and LOI of 39.6%. Compared with unmodified MF rigid foams, toughing rigid closed-cell MF foams possess excellent pulverization rate, compressive strength, bending strength, cellular structure, thermal insulation, and flame retardancy.

Properties of Mortars Mixed with Polystyrene and Hemp Fiber Wastes

2021 ◽  
Author(s):  
Apised Suwansaard
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Water Absorption ◽  
Fiber Content ◽  
Partial Replacement ◽  
Hemp Fiber ◽  
Line Crack ◽  
Better Than

When polystyrene (PS) and hemp fiber waste were mixed into the sand aggregate, some physical-mechanical properties of mortar changed. The PS and hemp fiber were tested as partial replacements for sand in mortar with three designated percentages of 2.5, 5.0 and 10.0% by mass. The properties of mortar with PS were found to be better than that of the mortar with hemp fiber. The water absorption of mortar with PS was comparable with the reference mortar but lower than that of mortar with hemp fiber. The compressive strength of the mortar with PS was higher than that with hemp fiber whereas the tensile strength of the mortar with 2.5% PS and hemp fiber was comparable and was higher than that of the reference mortar. The thermal conductivity of a wall plastered by mortar containing PS decreased as the PS content was increased, whereas the thermal conductivity of a wall plastered by mortar containing hemp fiber increased as the hemp fiber content was increased. Thick crack was detected in the reference wall while hair line crack occurred from the wall plastered with PS and hemp fiber mortars. The results indicated that 10.0% PS could be used as a partial replacement for sand in mortar with an improvement in some of the properties of the mortar.

Incorporation of Iraqi Rocks in the Production of Eco-Friendly Cement Mortar

2020 ◽  
Vol 38 (10A) ◽  
pp. 1522-1530
Author(s):  
Rawnaq S. Mahdi ◽  
Aseel B. AL-Zubidi ◽  
Hassan N. Hashim
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Compressive Strength ◽  
Water Absorption ◽  
Structural Properties ◽  
Mechanical Milling ◽  
Cement Mortar ◽  
Cement Mortars

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.

MEEHANITE GB300

Alloy Digest ◽  
2020 ◽  
Vol 69 (11) ◽  
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Gray Cast Iron ◽  
High Strength ◽  
Heat Treating ◽  
Spheroidal Graphite ◽  
Cast Irons ◽  
Test Pieces ◽  
Temperature Performance

Abstract Meehanite GB300 is a pearlitic gray cast iron that has a minimum tensile strength of 300 MPa (44 ksi), when determined on test pieces machined from separately cast, 30 mm (1.2 in.) diameter test bars. This grade exhibits high strength while still maintaining good thermal conductivity and good machinability. It is generally used for applications where the thermal conductivity requirements preclude the use of other higher-strength materials, such as spheroidal graphite cast irons, which have inferior thermal properties. This datasheet provides information on physical properties, hardness, tensile properties, and compressive strength as well as fatigue. It also includes information on low and high temperature performance as well as heat treating, machining, and joining. Filing Code: CI-75. Producer or source: Meehanite Metal Corporation.

The effect of organofluorine additives on the morphology, thermal conductivity and mechanical properties of rigid polyurethane and polyisocyanurate foams

2021 ◽  
pp. 0021955X2098715
Author(s):  
Cosimo Brondi ◽  
Ernesto Di Maio ◽  
Luigi Bertucelli ◽  
Vanni Parenti ◽  
Thomas Mosciatti
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Cell Size ◽  
Flexural Properties ◽  
Anisotropy Ratio ◽  
Cell Content ◽  
Average Cell Size ◽  
Average Cell ◽  
Thermal Insulating ◽  
Liquid Type

This study investigates the effect of liquid-type organofluorine additives (OFAs) on the morphology, thermal conductivity and mechanical properties of rigid polyurethane (PU) and polyisocyanurate (PIR) foams. Foams were characterized in terms of their morphology (density, average cell size, anisotropy ratio, open cell content), thermal conductivity and compressive as well as flexural properties. Based on the results, we observed that OFAs efficiently reduced the average cell size of both PU and PIR foams, leading to improved thermal insulating and mechanical properties.

scholarly journals Influence of the surface treatment of tire rubber residues added in mortars

2008 ◽  
Vol 1 (2) ◽  
pp. 113-120 ◽  
Author(s):  
A. C. Marques ◽  
J. L. Akasaki ◽  
A. P. M. Trigo ◽  
M. L. Marques
Keyword(s):  
Mechanical Properties ◽  
Aqueous Solution ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Surface Treatment ◽  
Water Absorption ◽  
Modulus Of Elasticity ◽  
Tire Rubber ◽  
Flow Test ◽  
Made In

In this work it was evaluated the influence tire rubber addition in mortars in order to replace part of the sand (12% by volume). It was also intended to verify if the tire rubber treatment with NaOH saturated aqueous solution causes interference on the mechanical properties of the mixture. Compressive strength, splitting tensile strength, water absorption, modulus of elasticity, and flow test were made in specimens of 5cmx10cm and the tests were carried out to 7, 28, 56, 90, and 180 days. The results show reduction on mechanical properties values after addition of tire rubber and decrease of the workability. It was also observed that the tire rubber treatment does not cause any alteration on the results compared to the rubber without treatment.

scholarly journals Biodegradable, Flame-Retardant, and Bio-Based Rigid Polyurethane/Polyisocyanurate Foams for Thermal Insulation Application

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1816 ◽  
Author(s):  
Marcin Borowicz ◽  
Joanna Paciorek-Sadowska ◽  
Jacek Lubczak ◽  
Bogusław Czupryński
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Water Absorption ◽  
Flame Retardant ◽  
Functional Properties ◽  
Apparent Density ◽  
Seed Oil ◽  
Mustard Seed ◽  
Hydroxyl Groups ◽  
Processing Times

This article raised the issue of studies on the use of new bio-polyol based on white mustard seed oil and 2,2’-thiodiethanol (3-thiapentane-1,5-diol) for the synthesis of rigid polyurethane/polyisocyanurate (RPU/PIR) foams. For this purpose, new formulations of polyurethane materials were prepared. Formulations contained bio-polyol content from 0 to 0.4 chemical equivalents of hydroxyl groups. An industrial flame retardant, tri(2-chloro-1-methylethyl) phosphate (Antiblaze TCMP), was added to half of the formulations. Basic foaming process parameters and functional properties, such as apparent density, compressive strength, brittleness, absorbability and water absorption, aging resistance, thermal conductivity coefficient λ, structure of materials, and flammability were examined. The susceptibility of the foams to biodegradation in soil was also examined. The increase in the bio-polyol content caused a slight increase in processing times. Also, it was noted that the use of bio-polyol had a positive effect on the functional properties of obtained RPU/PIR foams. Foams modified by bio-polyol based on mustard seed oil showed lower apparent density, brittleness, compressive strength, and absorbability and water absorption, as well as thermal conductivity, compared to the reference (unmodified) foams. Furthermore, the obtained materials were more resistant to aging and more susceptible to biodegradation.

scholarly journals Effect of Curing Method on Properties of Lightweight Foamed Concrete

2018 ◽  
Vol 7 (2.29) ◽  
pp. 927 ◽  
Author(s):  
Bishir Kado ◽  
Shahrin Mohammad ◽  
Yeong Huei Lee ◽  
Poi Ngian Shek ◽  
Mariyana Aida Ab Kadir
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Water Absorption ◽  
Precast Concrete ◽  
Construction Materials ◽  
Splitting Tensile Strength ◽  
Structural Members ◽  
Lightweight Construction ◽  
Foamed Concrete ◽  
Curing Method

Lightweight construction is aimed to achieve a sustainable feature by reducing transportation frequency and construction materials usage during construction phase. Lightweight precast concrete may serve an alternative for the lightweight construction. There are rarely application can be found for structural members as lightweight panels always to be used for secondary or non-load bearing members. This paper presents an experimental study on properties (compressive strength, splitting tensile strength, water absorption) of lightweight foamed concrete (LFC) at two different curing methods. LFC with densities of 1500, 1700, and 1800 kg/m3, cement-sand ratio of 2:1 and water-cement ratio of 0.5 were investigated. The results showed LFC can be produced with the properties ofdensity range of 1500 to 1800 kg/m3 and corresponding compressive strength of 10 to 39 MPa. The higher the density of LFC, the less the water absorption for all the curing method considered, the highest and the lowest water absorption was 11.3% and 2.0% for 1500 kg/m3 cured in water and 1800 kg/m3 cured in air respectively. Compressive strength of LFC increases with age and density while water cured LFC has high compressive strength. Splitting tensile strength increases with density of LFC, but air cured LFC has more splitting tensile strength than water cured of the same density. The highest splitting tensile strength recorded was 3.92 MPa for 1800 kg/m3 cured in air, which was about 16% of its compressive strength at 28 days of curing age. These properties are important and can be applied to LFC precast structural members with air or water curing method which have less references for LFC in structural usage.  

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