scholarly journals A Recycling Alternative for Expanded Polystyrene Residues Using Natural Esters

2022 ◽  
Author(s):  
Luisa V. García-Barrera ◽  
Dafne L. Ortega-Solís ◽  
Gabriela Soriano-Giles ◽  
Nazario López ◽  
Fernando Romero-Romero ◽  
...  
Keyword(s):  
Environmental Problem ◽  
Good Alternative ◽  
Expanded Polystyrene ◽  
Raw Material ◽  
Omega 3 ◽  
Scanning Calorimetry ◽  
Fishing Activity ◽  
Polystyrene Waste ◽  
Recovered Material

Abstract The objective of this research is to provide a new recycling method for one of the most consumed plastics today, since it is used for the manufacture of a wide variety of industrial products, which leads to an environmental problem caused by incorrect handling and final disposal.The dissolution of expanded polystyrene waste (WEP) was evaluated by using natural esters for its post treatment and recovery. The use of omega-3 as a natural solvent creates an opportunity to take advantage of natural biomass, since it can be obtained from the residues from the fishing activity, this being an economic advantage for obtaining raw material and also friendly with the environment.For the development of this research, expanded polystyrene containers were used, as well as omega-3 and glyceryl tributyrate as natural solvents and ethyl butyrate as synthetic solvent, methanol and isopropanol for recovery and cleaning of the polystyrene. The characterization of the recovered material was carried out with thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and infrared spectroscopy (FTIR) techniques. The experimental data obtained indicated that the use of these esters is a good alternative for the recycling of expanded polystyrene.

scholarly journals Characterization of Li2O-Al2O3-SiO2 glass-ceramics produced from a Brazilian spodumene concentrate

Cerâmica ◽  
2019 ◽  
Vol 65 (375) ◽  
pp. 366-377 ◽  
Author(s):  
L. B. Rebouças ◽  
M. T. Souza ◽  
F. Raupp-Pereira ◽  
A. P. Novaes de Oliveira
Keyword(s):  
Structural Changes ◽  
Glass Ceramics ◽  
Nucleating Agent ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Heating Microscopy ◽  
Shock Resistance ◽  
High Thermal Shock Resistance

Abstract Glass-ceramics in the LAS (Li2O-Al2O3-SiO2) system with high thermal shock resistance were successfully obtained using Brazilian spodumene concentrate as the main raw material (80-70 wt%). Two compositions (Li2O.Al2O3.nSiO2) were produced with n= 2 and 4, near to the stoichiometric compositions of β-eucryptite and β-spodumene. The characteristic temperatures of parent glasses were determined by contact dilatometry, differential scanning calorimetry and heating microscopy. The crystallization mechanism and the effect of the nucleating agent (TiO2.2ZrO2) required to promote volume crystallization in the parent glasses were investigated. Microstructural and structural changes with temperature were also evaluated by optical microscopy and X-ray diffraction. The obtained glass-ceramics presented coefficients of thermal expansion between -0.370x10-6 and 4.501x10-6 °C-1 in the 22 to 700 °C range.

scholarly journals IMPROVING SOLUBILITY AND DISSOLUTION OF A NATURAL PRODUCT APIGENIN VIA PREPARATION OF SOLID DISPERSION BY HOT MELT EXTRUSION

2021 ◽  
pp. 47-52
Author(s):  
SOFI N. STIANI ◽  
TAOFIK RUSDIANA ◽  
ANAS SUBARNAS
Keyword(s):  
Solid Dispersion ◽  
Water Solubility ◽  
Practical Method ◽  
Hot Melt Extrusion ◽  
Raw Material ◽  
Melt Extrusion ◽  
Scanning Calorimetry ◽  
Twin Screw ◽  
Hot Melt

Objective: Hot Melt Extrusion (HME) is one of the techniques for preparing a solid dispersion hydrophilic excipient known as a no solvents practical method to increase the solubility of drugs. Apigenin (APG) has properties that thermal stable with melting point 345-350 °C but very low solubility in the water around 1,35 µg/ml. The polymer is stable in the HME method are Soluplus and Kollidon VA 64. The study aims to optimize the kind of polymer in HME formulae to improve the solubility and dissolution rate of apigenin by solid dispersion using hot-melt extrusion. Methods: Apigenin 10–50% w/w and Kollidon®VA 64 or Soluplus® and combination of Kollidon®VA 64 and Soluplus® were mixed, and the resulting blends extruded using a twin-screw extruder (Teach-Line ZK25T). Characterization of apigenin extrudates conducted using scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy, powder X-ray diffractometry, and dissolution. Results: Solubility studies presented enhancement in apigenin of 10%/Soluplus®90%; 10% w/w apigenin/Kollidon®VA 64 (90%); and 33,3% w/w apigenin/Kollidon®VA 64 33,3% mix Soluplus® 33,3% increased more than 18,25; 16,18-and 8,52-fold in water, respectively. Furthermore dissolution studies showed enhancement in apigenin percent release of 10%/Soluplus®90%; 10% w/w apigenin/Kollidon®VA 64 90%; and 33,3% w/w apigenin/Kollidon®VA 64 33,3% mix Soluplus® 33,3% tablet apigenin HME up to 34,29%; 69,75% and 30,69%, respectively. Conclusion: The formulation of 10% w/w Apigenin and 90% Soluplus® using hot-melt extrusion able to increase water solubility approximately 18,25-fold than raw material apigenin.

scholarly journals Thermoanalytical study and characterization of native starches of Paraná pine seeds (Araucaria angustiofolia, Bert O. Ktze) and European chestnut seeds (Castanea sativa, Mill)

2009 ◽  
Vol 34 (1) ◽  
pp. 07-12 ◽  
Author(s):  
S. C. W. Bicudo ◽  
I. M. Demiate ◽  
G. Bannach ◽  
L. G. Lacerda ◽  
M. A. S. Carvalho Filho ◽  
...  
Keyword(s):  
Amylose Content ◽  
Castanea Sativa ◽  
Raw Material ◽  
Scanning Calorimetry ◽  
Thermoanalytical Study ◽  
Thermoanalytical Techniques ◽  
European Chestnut ◽  
Carbohydrate Storage ◽  
Castanea Sativa Mill

Starch is the most important carbohydrate storage in plants. It is a raw material with diverse botanical origins, and is used by the food, paper, chemical, pharmaceutical, textile and other industries. In this work, native starches of Paraná pine seeds (pinhão) (Araucária angustiofolia, Bert O. Ktze) and european chestnut seeds (Castanea sativa, Mill) were studied by thermoanalytical techniques: thermo-gravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC), as well as X-ray powder patterns diffractometry. Apparent and total amylose content was also determined.

scholarly journals Characterization of expanded polystyrene waste as binder and coating material

2021 ◽  
pp. e00804
Author(s):  
Elkin I. Gutierrez-Velasquez ◽  
Sergio Neves Monteiro ◽  
Henry A. Colorado
Keyword(s):  
Expanded Polystyrene ◽  
Coating Material ◽  
Polystyrene Waste

scholarly journals Mechanical Characterization of Gypsum Composites Containing Inert and Insulation Materials from Construction and Demolition Waste and Further Application as A Gypsum Block

Materials ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 193 ◽  
Author(s):  
Paola Villoria Sáez ◽  
Mercedes del Río Merino ◽  
Marica Sorrentino ◽  
César Porras Amores ◽  
Jaime Santa Cruz Astorqui ◽  
...  
Keyword(s):  
Mechanical Characteristics ◽  
Surface Hardness ◽  
Expanded Polystyrene ◽  
Raw Material ◽  
Construction And Demolition Waste ◽  
Demolition Waste ◽  
Density Surface ◽  
Reference Samples ◽  
Physical And Mechanical Characteristics

This article analyzes the feasibility of using construction and demolition waste (expanded polystyrene, ceramic, and concrete waste) in a gypsum matrix to manufacture plaster for interior coatings or for prefabricated elements for interior partitions. To do this, several gypsum specimens were prepared (4 × 4 × 16 cm) incorporating different percentages of waste based on the weight of the gypsum (25%, 50%, and 75% of ceramic, concrete, and a mixture of both). Reference samples were also produced (without additions) to compare the results obtained. The compounds with the best performance were selected and lightened by preparing other samples in which 1/3 and 2/3 of the volume of ceramic, concrete, and mixed waste were replaced with expanded polystyrene (EPS). All samples were tested in the laboratory and the following physical and mechanical characteristics were determined: density, surface hardness, flexural strength, compressive strength, capillary water absorption, and thermal conductivity. Several applications were proposed for the selected compounds. A gypsum block with a sandwich configuration was obtained (40 × 20 × 10 cm) using the optimum compound. The block was further tested regarding its density and compression strength. A comparative analysis showed that it is possible to produce materials with a gypsum matrix by adding ceramic, concrete, and EPS waste, improving the behavior of the traditional gypsum and enabling them to be applied in various construction applications. These applications have a lower environmental impact than ordinary ones because they use less primary raw material, due to the reuse of waste.

scholarly journals Production and characterization of the mechanical and thermal properties of expanded polystyrene with recycled material

2017 ◽  
Vol 21 (2) ◽  
Author(s):  
Gina Paola Barrera Castro ◽  
John Jairo Olaya Florez ◽  
Luz Marina Ocampo Carmona
Keyword(s):  
Thermal Properties ◽  
Steady State ◽  
Failure Load ◽  
Expanded Polystyrene ◽  
Mechanical And Thermal Properties ◽  
Scanning Calorimetry ◽  
Hot Plate ◽  
Steady State Temperature ◽  
Recycled Material

<p>Three materials were made with mixtures of virgin expanded polystyrene (EPS) grade S3 and recycled material from multipurpose EPS packaging. The latter was subjected to washing and grinding in a blade mill, with percentages by weight of recycled material 10, 15, and 20%. The mechanical properties of these materials were evaluated by testing compressive strength and flexural,  impact, and thermal properties using the techniques of differential scanning calorimetry and thermogravimetry. Hot plate and steady state temperature profiles in a non-steady state were simulated with Octave 3.6.4. The results obtained for the three mixtures showed little variation in the properties of compression, impact, glass transition, and thermal diffusivity with respect to the reference material. The regularity of the decline in mass loss as a function of temperature evidences homogeneity in the samples. The flexural strength decreased the maximum failure load compared to the virgin material, and the thermal conductivity exceeded 0.06W/mK, reducing their insulating capacity. These materials can be industrially manufactured in order to produce packaging, caissons, and spheres, among other things.</p>

scholarly journals Thermoanalytical study and characterization of native starches of Paraná pine seeds (Araucaria angustiofolia, Bert O. Ktze) and European chestnut seeds (Castanea sativa, Mill)

2018 ◽  
Vol 34 (1) ◽  
pp. 07
Author(s):  
S. C. W. Bicudo ◽  
Ivo Mottin Demiate ◽  
Gilbert Bannach ◽  
Luiz Gustavo Lacerda ◽  
Marco Aurelio Da Silva Carvalho Filho ◽  
...  
Keyword(s):  
Amylose Content ◽  
Castanea Sativa ◽  
Raw Material ◽  
Scanning Calorimetry ◽  
Thermoanalytical Study ◽  
Thermoanalytical Techniques ◽  
European Chestnut ◽  
Carbohydrate Storage ◽  
Castanea Sativa Mill

Starch is the most important carbohydrate storage in plants. It is a raw material with diverse botanical origins, and is used by the food, paper, chemical, pharmaceutical, textile and other industries. In this work, native starches of Paraná pine seeds (pinhão) (Araucaria angustiofolia, Bert O. Ktze) and european chestnut seeds (Castanea sativa, Mill) were studied by thermoanalytical techniques: thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC), as well as X-ray powder patterns diffractometry. Apparent and total amylose content was also determined.

scholarly journals Strength and Durability of Polystyrene Concrete

2021 ◽  
Vol 9 (5) ◽  
pp. 166-171
Author(s):  
Ankur Arun Kulkarni
Keyword(s):  
Expanded Polystyrene ◽  
Raw Material ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Expansive Agent ◽  
Natural Aggregates ◽  
Polystyrene Waste ◽  
In The Beginning ◽  
Solid Form ◽  
Strength And Durability

Now a day the construction is having rapid pace, and it has increased the requirement of raw material of construction especially coarse aggregate. In order to conserve the natural resources, use of plastic waste as partial replacement of natural aggregate in production of concrete will be a right step. This research paper discusses about the study and experimental work of “Polystyrene Concrete”, comprising of polystyrene waste shredded aggregates. Polystyrene concrete is a type of concrete, produced from a mixture of cement, sand and expanded polystyrene aggregate (EPS or UEPS aggregates). Thermoplastic polymeric material which is in the beginning in the solid form (UEPS) and it can be expanded by the use of steam and an expansive agent is called as Polystyrene. The polystyrene waste shredded to size of coarse and fine aggregate is used to replace 40% of natural aggregates. Nine trial mixes with varying proportion of these three types of polystyrene waste shredded aggregates and water-cement ratio are used. The workability of the fresh concrete mix as well as compressive strength of concrete at 28 days was obtained. This study has revealed that the polystyrene waste can be effectively used for production of resilient light weight concrete. The polystyrene concrete is best suited material for non-load bearing resilient concrete structures such as partition walls and facades.

scholarly journals A Study of The Properties of Forming Mixtures Containing Polystyrene Wastes

2021 ◽  
Vol 5 (2) ◽  
pp. 14-19
Author(s):  
Olena Dan ◽  
Larysa Trofimova
Keyword(s):  
Gas Permeability ◽  
Raw Materials ◽  
Polymeric Materials ◽  
Expanded Polystyrene ◽  
Raw Material ◽  
Sound Insulation ◽  
Ferrous Alloys ◽  
Insulation Systems ◽  
Polymeric Wastes ◽  
Polystyrene Waste

Expanded polystyrene is widely used as a material for packaging, in modern construction as a heat and sound insulation layer, in thermal insulation systems for buildings, as well as tanks and pipelines. It is additionally used in foundry engineering for the production of models which are gasified during the production of castings from ferrous and non-ferrous alloys under the contact with liquid metal. The use of expanded polystyrene products is associated with waste generation, both in production and in consumption. About 40–50 kg/person of polystyrene waste is generated per year. The peculiarity of polymeric wastes is their resistance to aggressive environments. They do not rot and the destruction processes in natural conditions proceed rather slowly, with the formation of harmful substances that poison the environment. Therefore, the problem of the processing of waste from polymeric materials is of great importance, not only from the standpoint of environmental protection, but also due to the fact that in conditions of a shortage of polymer raw materials, this waste becomes a powerful raw material resource. This article describes the prospects for recycling expanded polystyrene wastes in foundry engineering. In this work, the properties of molding and core sands containing a combined binder, consisting of a solution of expanded polystyrene wastes in turpentine and clay were investigated, and their main characteristics (weight during stretching and crumbling) were determined. Molding and core mixtures, which contain only a binder in the form of a solution of expanded polystyrene in turpentine, have a crude strength of not more than 0.01 MPa. The introduction of a mixture of clay in the amount of 2–3% allows a crude strength of the mixture of up to 0.05 MPa to be obtained. After drying, the investigated mixtures containing a solution of expanded polystyrene wastes and clay have a tensile strength of up to 2.1 MPa. Mixtures into which a solution of polystyrene wastes and clay was introduced have an insignificant gas capacity and satisfactory gas permeability.

Light-cured dental composites characterization by Electron Microscopy

1990 ◽  
Vol 48 (4) ◽  
pp. 428-429
Author(s):  
B. M. Culbertson ◽  
M. L. Devinev ◽  
E. C. Kao
Keyword(s):  
Electron Microscopy ◽  
Mechanical Analysis ◽  
Service Performance ◽  
Dental Composite ◽  
Dental Composites ◽  
Neat Resin ◽  
Scanning Calorimetry ◽  
Research Meeting ◽  
Formulation Variables

The service performance of current dental composite materials, such as anterior and posterior restoratives and/or veneer cements, needs to be improved. As part of a comprehensive effort to find ways to improve such materials, we have launched a broad spectrum study of the physicochemical and mechanical properties of photopolymerizable or visible light cured (VLC) dental composites. The commercially available VLC materials being studied are shown in Table 1. A generic or neat resin VLC system is also being characterized by SEM and TEM, to more fully understand formulation variables and their effects on properties.At a recent dental research meeting, we reported on the differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) characterization of the materials in Table 1. It was shown by DSC and DMA that the materials are substantially undercured by commonly used VLC techniques. Post curing in an oral cavity or a dry environment at 37 to 50°C for 7 or more hours substantially enhances the cure of the materials.

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