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The extensive use of external thermal insulation composite systems (ETICS) using expanded polystyrene (EPS) for building insulation in Germany has resulted in accumulating end-of-life EPS-ETICS. To address limited waste management options and enhance EPS circularity, alternative recycling options like pyrolysis or solvent-based recycling need to be implemented. However, efficient recycling requires ex-ante analyses of the corresponding reverse logistics networks, including all necessary pre-treatment and transport processes. This study aims to develop a decision support system to determine optimal EPS-ETICS waste management by minimising the net present value of the corresponding network design. Our mixed-integer linear optimisation model considers decisions on technology, capacity, and location for pre-processing and recycling facilities as well as on material flow allocation. Applied to a German case study, our model finds pyrolysis and solvent-based recycling economically superior to current waste treatment in waste incineration plants. We present an optimal network design combining central pyrolysis with decentral pre-processing. A scenario analysis shows fluctuating styrene and polystyrene prices might favour solvent-based recycling over the optimal choice in pyrolysis, with minor overall cost differences. Further, legal recycling quotas of at least 40% would be necessary to promote solvent-based recycling and enhance EPS circularity beyond what is achievable through pyrolysis. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the potential of upcycling Expanded Polystyrene (EPS) waste collected from food packaging into a membrane for microalgae harvesting, in which membrane filtration often challenges fouling and pore blocking. The target species is Spirulina platensis, with Chlorella vulgaris as a comparison agent. The membrane was fabricated from used Styrofoam, which typically ends up as single-use food packaging waste. In this study, PVP was used as an additive at varying concentrations, from 2 wt.% to 8 wt.%. The experimental results indicated that despite varying PVP concentrations, all EPS waste membranes exhibited near-complete recovery of Spirulina platensis biomass extraction. Despite the similar harvesting efficiency, EPS/PVP-8 exhibited the largest flux of 970.5 LMH/Bar, which is twice the value of the pristine EPS waste membrane. All membranes were hydrophilic; however, hydrophobicity increased with PVP concentration. SEM micrographs revealed that PVP enlarged the membrane surface pores and improved connectivity within the membrane's structure, ensuring efficient flow. The EPS waste membrane offers promising insights for sustainable materials and wastewater treatment. The upcycling of EPS waste into flat sheet membranes not only addresses the problem of Styrofoam waste accumulation but also paves the way to transform waste into valuable products. [ABSTRACT FROM AUTHOR]

With an increasing energy deficit, improving the thermal properties of building materials is nowadays a priority. The incorporation of expanded polystyrene (EPS) and expanded perlite (EP) into cement mortar has shown enormous potential to improve overall thermal performance. This study aims to numerically evaluate the efficiency of using EPS and EP reinforced composites as coating mortars. First, several reinforced mortars were prepared by adding different proportions of EPS and EP to the cement mortar. The thermal, mechanical and microstructural performances of EPS and EP mortars were subsequently analyzed using Hot Disk and MATEST instruments as well as FTIR spectroscopy and XRD analysis. COMSOL Multiphysics software was then used to simulate the inner temperature variation of a hollow brick coated on both sides with the optimal reinforced mortar mix. The results showed that an increase in the amount of reinforcing material led to a reduction in both mechanical strength and thermal properties of the mortar. Optimum performance could be achieved by incorporating 2.5% expanded polystyrene into the mortar, which resulted in approximately 37%, 15%, and 26% reduction in thermal conductivity, thermal diffusivity, and volumetric heat capacity, respectively, compared to standard mortar. This thermal improvement was achieved while ensuring a satisfactory mechanical and chemical properties. By applying varying thicknesses of this reinforced mortar to the brick, the internal surface temperature was reduced by approximately 0.2–1.8 °C during periods of maximum flux exposure. Therefore, the application of these composites as a thermally enhanced coating mortar on building walls seems to be an adequate solution. [ABSTRACT FROM AUTHOR]

Incorporating waste to produce new environmentally friendly construction products has become one of the great challenges of the industry nowadays. The aim of this research is to analyse the behaviour of novel gypsum composites against water action, incorporating recycled rubber aggregates (up to 8.5% vol.) and dissolved expanded polystyrene (up to 10.0% vol.). To this end, a total of 10 dosages have been proposed with the progressive substitution of natural resources by these secondary raw materials. The results show how it is possible to reduce the total water absorption of the gypsum composites by up to 8.3% compared to traditional gypsum material. In addition, it is also possible to reduce water absorption by capillary by up to 52.7%, resulting in lighter composites with good performance against water action. In all composites analysed, the mechanical strengths exceeded the minimum values of 1 MPa in bending and 2 MPa in compression, making them an optimal solution for the development of lightweight prefabricated products for damp rooms. [ABSTRACT FROM AUTHOR]

The prime objective of the current research work was to understand the role of microwave-assisted pyrolysis for the upgradation of expanded polystyrene (EPS) waste into valuable aromatic hydrocarbons. Ethyl acetate solvent was used to dissolve the EPS to enhance the homogeneous dispersion of EPS with susceptor particles. Biochar obtained from the pyrolysis was used as a susceptor. The design of experiments method was used to understand the role of microwave power (300 W, 450 W, and 600 W) and susceptor quantity (5 g, 10 g, and 15 g) in the pyrolysis process. The pyrolysis was conducted till the temperature reached up to 600 °C, and this temperature was achieved in the time interval of 14–38 min based on the experimental conditions. The obtained average heating rates varied in the range of 15 to 41 °C/min to attain the pyrolysis temperature. The EPS feed was converted into char (~ 2.5 wt.%), oil (51 to 60 wt.%), and gaseous (37 to 47 wt.%) products. The specific microwave energy (J/g) was calculated to know the energy requirement; it increased with an increase in susceptor quantity and microwave power, whereas specific microwave power (W/g) was a function of microwave power and increased from 15 to 30 W/g. The predicted values calculated using the model equations closely matched the actual values showing that the developed model equations via optimization had a good fit. The obtained pyrolysis oil physicochemical properties including viscosity (1 to 1.4 cP), density (990 to 1030 kg/m3), heating value (39 to 42 MJ/kg), and flash point (98 to 101 °C) were thoroughly analyzed. The pyrolysis oil was rich in aromatic hydrocarbons and it was predominantly composed of styrene, cyclopropyl methylbenzene, and alkylbenzene derivates. [ABSTRACT FROM AUTHOR]

The application of the expanded polystyrene (EPS) waste to the functional material is still a challenge. The hydrophobic property of polystyrene has a potential to create a superhydrophobic surface. Here, we use expanded polystyrene waste to coat surfaces in two different ways—spray coating and dip coating—to produce superhydrophobic surfaces for food packaging. The ZnO was employed to make the surface rougher. However, the combination of ZnO and EPS waste produces only a hydrophobic surface. For spray coating and dip coating, the maximum water contact angle is 119° and 125° respectively. The scanning electron microscope (SEM) picture reveals many holes that increase the surface's roughness. The hydrophobic surface significantly cuts down on cleaning time. According to the food packaging parameter test mandated by the Indonesian Food and Drug Administration (BPOM) (BPOM regulation No. 20, 2019), the coating complies with heavy metals and ethanol stimulant migration testing requirements for food packaging. However, the migration condition in acetic acid stimulant surpasses the maximum standard. The total migration in 3% acetic acid stimulant (40°C for 10 days) is 22.95 mg/dm2 while the maximum value is 10 mg/dm2.

A degradation mechanism of polystyrene (PS) in mealworms reared on expanded PS (EPS) was investigated by its decrease in molecular weight and change in chemical structure. A 33% decrease in molecular weight was observed for the digested PS in the frass after 1 week of feeding to mealworms. The FT-IR and py-GC/MS spectra of the digested PS showed radical oxidative reactions taking place in the mealworm body. The presence of hydroperoxide, alcohol and phenol groups was confirmed, and dimer fragments of styrene with quinone and phenol groups were obtained. The decrease in molecular weight and the alternation of benzene rings indicated that autoxidation and quinonization via phenolic intermediates occurred simultaneously in the mealworm body. The survival rate of mealworms reared on EPS was higher than that of starved worms, indicating that EPS was a nutrient source. However, no weight gain was observed in mealworms fed EPS alone. Comparison with the mixed diets with bran or urethane foams (PU) indicated that protein, phosphorus and magnesium components absent from EPS were required for mealworm growth. [ABSTRACT FROM AUTHOR]

Expanded polystyrene (EPS), commonly used as floating material in mariculture, could be a significant source of coastal PS waste. Prolonged floating in seawater leads to the formation of dense biofilms, which could disperse into the oceanic environment and spread to water bodies even the seabed as EPS deteriorates into microplastics. To understand the bacterial community structure in EPS surface biofilms, this study employed high-throughput sequencing technology to analyze the biofilms on EPS foams used in offshore mariculture aside Xiamen. Analysis of 24 biofilm samples from different seasons revealed significant differences in bacterial community structures. However, we have identified the core groups of the EPS biofilm, including Flavobacteriaceae, Rhodobacteraceae, Halomonadaceae, Exiguobacteriaceae, Vibrionaceae, and Pseudoalteromonadaceae. The Halomonadaceae and Exiguobacteriaceae are particularly attracted to the subtropical EPS material. In addition, groups with potential of degrading PS were identified, such as Alcanivorax, Pseudomonas, Acinetobacter, Exiguobacterium, Brevundimonas, and Bacillus, as well as the potential fish pathogen Acinetobacter johnsonii. The microbial biofilms formed on floating EPS demonstrate high diversity and are strongly influenced by environmental conditions. This study contributes to a deeper understanding of the interactions of bacteria in the biofilm with widely used and dispersed floating materials in the oceans. [ABSTRACT FROM AUTHOR]

Axial, flexure, and shear loads are the most common loads that could impact any structure. For instance, wall panels and columns majorly carry axial loads from the beam and slabs; they are also susceptible to flexure and shear loads from the wind or earthquake loads. Insulated concrete form (ICF) is a portable component of interconnected expanded polystyrene (EPS) panels filled with concrete. EPS remains in place and becomes part of the wall to enhance thermal resistance and structural performance. This paper focuses on an experiment that investigated the performance of ICF wall panels under axial compression and flexure. EPS with a higher density of 20 and 40 kg/m3 and a higher thickness of 50 and 100 mm was selected to prepare ICF wall panels for this experimental investigation. In addition, the plain concrete panel was cast for reference. Axial, flexure, and shear load-carrying capacity, load displacement, load–deflection profiles, crack propagation patterns, failure nature, and strain energy are analyzed and reported in this paper. It was observed that ICF panels were superior to plain concrete panels in terms of axial, flexure, and shear load-carrying capacity, failure nature, and absorbed strain energy.

Applicable and low‐cost ultrafiltration membranes based on waste polystyrene (WPS) blend and poly vinylidene fluoride (PVDF) were effectively cast on nonwoven support using phase inversion method. Analysis was done into how the WPS ratio affected the morphology and antifouling performance of the fabricated membranes. Cross flow filtration of pure water and various types of polluted aqueous solutions as the feed was used to assess the performance of the membranes. The morphology analysis shows that the WPS/PVDF membrane layer has completely changed from a spongy structure to a finger‐like structure. In addition, the modified membrane with 50% WPS demonstrated that the trade‐off between selectivity and permeability is met by a significant improvement in the rejection of the membrane with a reduction in permeate flux due to the addition of PVDF. With a water permeability of 50 LMH and 44 LMH, respectively, the optimized WPS‐PVDF membrane with 50% WPS could reject 81% and 74% of Congo red dye (CR) and methylene blue dye (MB), respectively. The flux recovery ratio (FRR) reached to 88.2% by increasing PVDF concentration with 50% wt. Also, this membrane has the lowest irreversible fouling (Rir) value of 11.7% and lowest reversible fouling (Rr) value of 27.9%. The percent of cleaning efficiency reach to 71%, 90%, and 85% after eight cycles of humic acid (HA), CR, and MB filtration, respectively, for the modified PS‐PVDF (50%–50%). However, higher PVDF values cause the membrane's pores to become clogged, increase the irreversible fouling, and decrease the cleaning efficiency. In addition to providing promising filtration results, the modified membrane is inexpensive because it was made from waste polystyrene, and as a result, it could be scaled up to treat colored wastewater produced by textile industries. Practitioner Points: Recycling of plastic waste as an UF membrane for water/wastewater treatment was successfully prepared and investigated.Mechanical properties showed reasonable response with adding PVDF.The modified membrane with 50% PS demonstrated that the trade‐off between selectivity and permeability is met by a significant improvement in the rejection. [ABSTRACT FROM AUTHOR]

The effect of magnetic water (MW) on mechanical properties (MP) of lightweight concretes (LWC's) made with expanded polystyrene was investigated. Eight different types of water were used. The water used were drinking water and raw water of the Karun River that each was magnetised at 0.5, 1 and 2 Tesla fields. Slump, water absorption, static elasticity modulus (Ec) and compressive, tensile, and flexural strength tests were performed. The results showed that the use of drinking water compared to river raw water provides higher MP. Using drinking water compared to the raw river water increased the efficiency of concrete by 3% and the compressive, tensile, flexural strength and Ec by 10%, 3%, 3%, and 2%, respectively. Using MW up to the 1 Tesla field intensity has a positive effect on concrete MP. Due to the use of MW with 1 Tesla intensity, compressive, tensile, and flexural strength and Ec increased by 24.4%, 6.1%, 3.9% and 0.5% in concretes made with drinking water and 12.4%, 3.6%, 3.4% and 2% in river raw water concretes. However, the MP of LWC's containing MW with intensity of more than 1 Tesla were almost similar to the case in which MW with 1 Tesla was used. [ABSTRACT FROM AUTHOR]

Plastics represent an integral part of our everyday lives, with various functions from packaging materials to insulation layers in our buildings. Pure expanded polystyrene (EPS) is a good example of a fully recyclable material. However, once polluted with other materials or substances, EPS becomes a serious environmental burden. In this work, waste EPS for the production of greener building composites with balanced properties and utility value was investigated. Natural aggregate (2/4 mm) was substituted with corresponding fractions of a thermoplastic alternative in portions of 25, 50, 75, and 100 vol.%. The comprehensive experimental investigation evaluated physical and mechanical properties, heat transport and accumulation, and water absorption characteristics. Due to the uniformly distributed plastic particles in the hardened cement-based matrix, the data revealed an important reduction in the dead weight of produced mortars, which also reduced thermal conductivity by up to 47%. On one hand, lightweight mortars showed partially reduced mechanical resistivity; on the other hand, the EPS bead-modified structure turned out to be effective in liquid water transport reduction. [ABSTRACT FROM AUTHOR]

Axial, flexure, and shear loads are the most common loads that could impact any structure. For instance, wall panels and columns majorly carry axial loads from the beam and slabs; they are also susceptible to flexure and shear loads from the wind or earthquake loads. Insulated concrete form (ICF) is a portable component of interconnected expanded polystyrene (EPS) panels filled with concrete. EPS remains in place and becomes part of the wall to enhance thermal resistance and structural performance. This paper focuses on an experiment that investigated the performance of ICF wall panels under axial compression and flexure. EPS with a higher density of 20 and 40 kg/m3 and a higher thickness of 50 and 100 mm was selected to prepare ICF wall panels for this experimental investigation. In addition, the plain concrete panel was cast for reference. Axial, flexure, and shear load-carrying capacity, load displacement, load–deflection profiles, crack propagation patterns, failure nature, and strain energy are analyzed and reported in this paper. It was observed that ICF panels were superior to plain concrete panels in terms of axial, flexure, and shear load-carrying capacity, failure nature, and absorbed strain energy. [ABSTRACT FROM AUTHOR]

The demand for lightweight aggregates in concrete compositions for diverse structural and non-structural applications in contemporary building construction has increased. This is to achieve a controllable low-density lightweight concrete, which reduces the overall structural weight. However, the challenge lies in achieving an appropriate strength in lightweight concrete while maintaining a lower unit weight. This research aims to evaluate the performance of lightweight concrete by integrating expanded polystyrene (EPS) as a partial replacement for coarse aggregate. Test specimens were cast by blending EPS with coarse aggregate at varying proportions of 0%, 15%, 30%, and 45%, while maintaining a constant water-to-binder ratio of 0.60. To enhance the bonding and structural capabilities of the proposed lightweight concrete mixes, reinforcement with 2% and 4% steel fibers by volume of the total concrete mix was incorporated. Silica fume was introduced into the mix to counteract the water hydrophobicity of EPS material and enhance the durability of lightweight concrete, added at a rate of 10% by weight of cement in all specimens. A total of 60 samples, including cylinders and beams, were prepared and cured over 28 days. The physical and mechanical properties of the lightweight EPS-based concrete were systematically examined through experimental testing and compared against a standard concrete mix. The analysis of the results indicates that EPS-based concrete exhibits a controllable low density. It also reveals that incorporating reinforcement materials, such as steel fibers, enhances the overall strength of lightweight concrete. [ABSTRACT FROM AUTHOR]

Some researchers contend that repurposing and reuse of EPS for artistic and aesthetic purposes represents a meaningful step in addressing the environmental challenges associated with its widespread commercial and single-use applications. It is in line with this thought that this review paper seeks to explore the wide range of creative and aesthetic applications of polystyrene across various disciplines, shedding light on its versatility, aesthetics, and functional qualities. The purpose of the review is to ascertain the contribution of the creative field to environmental sustainability through the (re)use of EPS. Taking a qualitative route, this review of literature is guided by the following research questions: (a) What are the inherent properties and characteristics of EPS? (b) In what myriad aesthetic contexts have EPS found utility and application? (c) What are the key challenges associated with employing this material for artistic purposes? Given the difficulty that accompanies the recycling options for EPS, its use in art has become another avenue for extending the material’s end-of-life use. However, the paper found that while some artists contribute to the development of a green society by using discarded EPS in their art, others contribute to the problem by choosing to use virgin EPS for their art because of benefits such as the material’s lightweight, ease of carving, and cheapness. Therefore, this paper recommends that if artists must use EPS, then they should make it a point of duty to go for discarded EPS and other plastic wastes to help the environment.

This paper discusses efforts made by past researchers to steady the expansive (problematic) soils using mechanical and chemical techniques - specifically with EPS beads, lime and fly ash. Administering swelling of problematic soils is critical for civil engineers to prevent structural distress. This paper summarizes studies on reduction of swelling potential using EPS, lime and fly ash individually. Chemical stabilization with lime and fly ash are conventional methods for expansive soil stabilization, with known merits and demerits. This paper explores the suitability of different materials under various conditions and stabilization mechanisms, including cation exchange, flocculation, and pozzolanic reactions. The degree of stabilization is influenced by various factors such as the type and amount of additives, soil mineralogy, curing temperature, moisture content during molding, and the presence of nano-silica, organic matter, and sulfates. Additionally, expanded polystyrene (EPS) improves structural integrity by compressing when surrounded clay swells, reducing overall swelling. Thus, EPS addresses limitations of chemicals by mechanical means. Combining EPS, lime and fly ash creates a customized system promoting efficient, long-lasting, cost-effective and eco-friendly soil stabilization. Chemicals address EPS limitations like poor stabilization. This paper benefits civil engineers seeking to control expansive soil swelling and prevent structural distress. It indicates potential of an EPS-lime-fly ash system and concludes by identifying research gaps for further work on such combinatorial stabilizer systems.

The demand for lightweight aggregates in concrete compositions for diverse structural and non-structural applications in contemporary building construction has increased. This is to achieve a controllable low-density lightweight concrete, which reduces the overall structural weight. However, the challenge lies in achieving an appropriate strength in lightweight concrete while maintaining a lower unit weight. This research aims to evaluate the performance of lightweight concrete by integrating expanded polystyrene (EPS) as a partial replacement for coarse aggregate. Test specimens were cast by blending EPS with coarse aggregate at varying proportions of 0%, 15%, 30%, and 45%, while maintaining a constant water-to-binder ratio of 0.60. To enhance the bonding and structural capabilities of the proposed lightweight concrete mixes, reinforcement with 2% and 4% steel fibers by volume of the total concrete mix was incorporated. Silica fume was introduced into the mix to counteract the water hydrophobicity of EPS material and enhance the durability of lightweight concrete, added at a rate of 10% by weight of cement in all specimens. A total of 60 samples, including cylinders and beams, were prepared and cured over 28 days. The physical and mechanical properties of the lightweight EPS-based concrete were systematically examined through experimental testing and compared against a standard concrete mix. The analysis of the results indicates that EPS-based concrete exhibits a controllable low density. It also reveals that incorporating reinforcement materials, such as steel fibers, enhances the overall strength of lightweight concrete.

A laboratory-based study was conducted to investigate the consumption and degradation of expanded polystyrene (EPS) by superworms (darkling beetle larvae, Zophobas morio; heterotypic synonym Zophobas atratus). Superworms fed on one of three diets (wheat bran control, EPS blocks, or EPS S-shaped chips) following a 60-second pretreatment with UV radiation or no UV radiation exposure. Loss-of-mass measurements were conducted every week for 4 weeks. Nutrients (nitrogen and phosphorus) and EPS degradation products in frass were determined as well as the superworm gut microbiome composition. The average loss of mass after 28 days was 34.7% for EPS blocks and 25.6% for S-shaped chips. Small quantities of nitrogen and phosphorus were found in the frass of superworms that fed on the EPS diet, but they were lower than those from wheat bran-fed superworms. Twenty-one EPS degradation products were identified in the frass of superworms on an EPS diet, including short-chain carboxylic acids, polyols, amino acids, metabolites of amino acids, and phosphoric acids. Pseudomonas aeruginosa (polystyrene degrader) and Stenotrophomonas sp. (nitrogen fixer and phosphorus solubilization promoter) were identified from the guts of superworms that fed on an EPS diet. Overall, superworms have the potential to deal with plastic waste degradation problems.

Hypothesis: The technology of preparing materials with desired dielectric constants is used in designing and manufacturing telecommunication equipment. Foaming of the polymers is an effective method to reduce their dielectric constant further, as the influence of the microstructural characteristics of the expanded polystyrene foams is important for their dielectric characteristics and mechanical properties. This article focuses on the effect of cell wall thickness of the expanded polystyrene foams on their dielectric constant, loss factor, hardness and resilience.Methods: Many samples of the expanded polystyrene foam with different porosity and overall thickness values were prepared using a specific thermal procedure in a programmable oven. At first, the physical properties such as density and porosity of the expanded polystyrene foams were measured. Next, their microstructural characteristics such as the average cell wall thickness of the expanded polystyrene foams were investigated using a scanning electron microscope. The dielectric constant and loss factor of the samples were assessed with a vector network analyzer with a lens horn antenna. The mechanical properties of the expanded polystyrene foams were evaluated according to Shore D hardness, and the value of mechanical energy stored in them was measured by a resilience tester.Findings: By increasing cell wall thickness in samples at equal overall thickness, the dielectric characteristics such as dielectric constant and dielectric loss factor increase by 12% and 53%, respectively. Moreover, the mechanical properties such as hardness and resilience reveal an increase of 40 and 42%, respectively, due to the increase of cell wall thickness in samples at the same overall thickness. While the dielectric constant and the dielectric loss factor decrease with the reduction of the overall thickness at the same cell wall thickness, the variation of the overall thickness depicts no effect on the hardness and resilience.

The aim of this study was to investigate the potential of upcycling Expanded Polystyrene (EPS) waste collected from food packaging into a membrane for microalgae harvesting, in which membrane filtration often challenges fouling and pore blocking. The target species is Spirulina platensis, with Chlorella vulgaris as a comparison agent. The membrane was fabricated from used Styrofoam, which typically ends up as single-use food packaging waste. In this study, PVP was used as an additive at varying concentrations, from 2 wt.% to 8 wt.%. The experimental results indicated that despite varying PVP concentrations, all EPS waste membranes exhibited near-complete recovery of Spirulina platensis biomass extraction. Despite the similar harvesting efficiency, EPS/PVP-8 exhibited the largest flux of 970.5 LMH/Bar, which is twice the value of the pristine EPS waste membrane. All membranes were hydrophilic; however, hydrophobicity increased with PVP concentration. SEM micrographs revealed that PVP enlarged the membrane surface pores and improved connectivity within the membrane’s structure, ensuring efficient flow. The EPS waste membrane offers promising insights for sustainable materials and wastewater treatment. The upcycling of EPS waste into flat sheet membranes not only addresses the problem of Styrofoam waste accumulation but also paves the way to transform waste into valuable products.

Expanded polystyrene (EPS) polymers are widely used in insulation and packaging applications. If their waste hasn't been managed well and due to their long degradation time, they will cause severe environmental problems for human beings, plants, and animals. Therefore, recycling could be one of the acceptable solutions to overcome such problems in addition to reinforcing them to recover the decay in properties resulting from recycling. In this work two types of EPS have been recycled at different temperatures from 140 to 260°C, and then reinforced by E-glass fibers in mat form and as random short fibers with varied composition from 5 to 25 wt%. The samples have been prepared by homemade thermal press and the tensile properties such as strength, modulus, and ductility have been investigated showing an obvious enhancement of these properties upon an increase in temperature to certain level and with fiber content and length exceeding their critical lengths. Furthermore, interfacial adhesion has been studied by estimating the strength and modulus efficiency factors. The results show that the E-glass fibers could improve the strength with more than 300%. [ABSTRACT FROM AUTHOR]

Featured Application: The findings of this study can be applied in engineering practice for the protection of buried pipelines and other underground life lines crossing under or near continuously expanding high-speed railway lines. High-speed railway (HSR) lines commonly operate over hundreds of kilometers, crossing several other large-scale infrastructures, such as highways, tunnels, bridges, and pipelines. This fact makes adjacent infrastructure more vulnerable to high-speed train (HST)-induced vibrations; thus, their potential distress should be carefully examined. The current study aims to assess the level of traffic-induced vibrations on the surface of buried pipelines vertically crossing under an HSR line. Firstly, the necessity to reduce high vibration levels is highlighted, utilizing a three-dimensional (3D) finite element model in conjunction with the moving load approach. Subsequently, an efficient mitigation measure is proposed to minimize these vibrations. For this purpose, a low-weight, high-performance geosynthetic fill material, i.e., expanded polystyrene (EPS) geofoam blocks, has been implemented between the HSR line and the buried pipeline to minimize the impact of vibrations. In this manner, HST-induced vibrations are reflected on EPS blocks, preventing them from reaching the pipeline surface. Based on this detailed parametric study, useful conclusions are drawn regarding the mechanical properties and geometry of the EPS protection layer. [ABSTRACT FROM AUTHOR]

This article presents the authors' comprehensive evaluation of the application of specific foam thermal insulation materials, namely expanded polystyrene (EPS) and extruded polystyrene (XPS), within railway substructures. The assessment extends to real-world conditions on the tracks of Slovak Railways (ŽSR), which share substantial similarities with other countries' railway networks. The assessment of structural composition and material selection considers these technical aspects, while technological feasibility and the environmental implications associated with material production, delivery, and incorporation into railway construction do not. Additionally, the thermal insulation materials' qualities are compared against conventional railway substructure materials. In these conventional setups, the thermal insulation layer often incorporates crushed aggregate of specified fractions and parameters in line with legislative standards. This article complements previous research conducted at the University of Žilina, focusing on the application of various thermal insulation materials within railway substructures. These materials were both experimentally tested (scale of 1:1) and numerically modelled, with results previously published by the authors. The published works detail the utilisation of diverse thermal insulation materials in railway substructures, primarily evaluating two crucial technical parameters: the protection of the subgrade surface against adverse effects of frost and, secondarily, their impact on the deformation resistance of the railway substructure. [ABSTRACT FROM AUTHOR]

A degradation mechanism of polystyrene (PS) in mealworms reared on expanded PS (EPS) was investigated by its decrease in molecular weight and change in chemical structure. A 33% decrease in molecular weight was observed for the digested PS in the frass after 1 week of feeding to mealworms. The FT-IR and py-GC/MS spectra of the digested PS showed radical oxidative reactions taking place in the mealworm body. The presence of hydroperoxide, alcohol and phenol groups was confirmed, and dimer fragments of styrene with quinone and phenol groups were obtained. The decrease in molecular weight and the alternation of benzene rings indicated that autoxidation and quinonization via phenolic intermediates occurred simultaneously in the mealworm body. The survival rate of mealworms reared on EPS was higher than that of starved worms, indicating that EPS was a nutrient source. However, no weight gain was observed in mealworms fed EPS alone. Comparison with the mixed diets with bran or urethane foams (PU) indicated that protein, phosphorus and magnesium components absent from EPS were required for mealworm growth.

This research investigated the feasibility of using waste-expanded polystyrene (EPS) and mortar to produce lightweight aggregate (LWA). The EPS extracted from the leftover backing waste was crushed into beads using an electric grinder and mixed in three different proportions with two types of mortars (with and without a superplasticizer). Physical property tests such as loose bulk density and water absorption were carried out for the LWA. Also, the compressive strength of the manufactured lightweight aggregate concrete (LWAC) was determined, and failure modes were discussed. The results indicate that using the EPS is effective for LWA. The loose bulk density is obtained at a range from 588 to 790kg/m3790\hspace{0.33em}{\text{kg/m}}^{3}, which meets the requirements of the American society for testing and materials C330 specification of LWA. For water absorption, the value obtained ranges from 6.45 to 14.05%, slightly higher than the normal aggregate due to the voids in the LWA. When using LWA containing a superplasticizer to produce LWAC, the compressive strength was higher than the concrete with LWA without a superplasticizer. The highest compressive strength for LWAC was 21 MPa.

Insulation products made of expanded polystyrene (EPS) are commonly utilized in buildings. However, Norwegian building regulations restrict the use of such combustible insulation due to an increased risk of fire spread and generation of smoke and toxic gases. Installation of fire protection coverings has been adopted as a mitigation strategy to address these safety risks. Notably, the current regulations lack pre-approved solutions describing what is considered an adequate protection of combustible insulation. The present study investigated the fire protection properties of selected coverings used to protect EPS insulation in inner walls. Eight comparative fire tests were conducted using an indicative fire resistance test furnace. The test specimens consisted of EPS blocks mounted on a wooden frame and covered with one or two layers of selected board coverings. The specimens were positioned vertically within the test furnace, and each fire test lasted for 10 or 15 min. Test results revealed that only two configurations consisting of either two layers of 12.5 mm gypsum boards or a combination of 12 mm oriented strand board (OSB) and 12.5 mm gypsum board showed no evidence of damage to the EPS substrate after a 15-min fire exposure. Consequently, the findings suggest that a total covering thickness of at least 24.5 mm, comprising two layers of boards, is necessary to prevent adverse effects on EPS insulation. Furthermore, fire tests conducted on coverings with introduced damages and defects showed that the affected area around the damages and defects were limited. For the standard EPS substrate, this area extended from 28 mm to 90 mm, while for the fire-retardant EPS substrate from 28 mm to 75 mm after a 10-min fire exposure. These results suggest that minor physical failures in the covering have limited impact on the fire safety of the system.

The use of photocatalysts in continuous stirred tank reactor (CSTR) systems allows for efficient and continuous water treatment, thus meeting the demand for scalable technology and comparative data in large-scale implementations. Hence, this study aims to explore the feasibility of a floating photocatalyst within a CSTR system for continuous water treatment. An expanded polystyrene (EPS)-TiO2 composite was synthesized following established methodologies, and their efficacy in removing the water pollutant methylene blue (MB) was compared for both batch and CSTR systems. A nonlinear first-order model was identified as the most suitable approach to accurately simulate MB degradation under experimental conditions, and the calculated pseudo-first-order degradation rate constant (kʹ) for the CSTR system (0.0126–0.0172/min) was found to be superior to that observed for the batch system (0.0113/min). In addition, an increase in the flow rate reduced the retention time, leading to lower MB removal efficiency for the CSTR system. In addition, the EPS-TiO2/UV system with a CSTR configuration was found to efficiently use light and energy based on the calculated quantum yield (Φ = 2.86 × 10–4) and electrical energy per order (EEO = 857.46 kWh/m3/order). The findings of this study contribute to the development of sustainable and efficient water treatment strategies, offering valuable insight into the implementation of practical water treatment processes. [ABSTRACT FROM AUTHOR]

The current high production of plastics has prompted the exploration of alternative pathways to facilitate recycling, aiming for a progressively sustainable society. This paper presents an alternative and affordable technology for treating waste expanded polystyrene (EPS) mixed with acetone in a 100:1 volume ratio to be used as 3D printing ink for Direct Ink Write technology. In order to optimize the printing parameters, a comprehensive study was conducted, evaluating different needle diameters, printing speeds, and bed temperature values to achieve homogenous pieces and a highly repeatable 3D printing process. Results showed that the main optimum printing parameters were using needles with diameters of 14 to 16 G and printing speeds ranging from 2 to 12 mm/s, which were found to yield the most uniform ribbons. Increasing the bed temperature, despite favoring acetone evaporation, led to the generation of more heterogeneous structures due to void growth inside the printed ribbons. Thus, employing room temperature for the bed proved to be the optimal value. Lastly, a comparative study between the starting material and the EPS after the printing process was conducted using FTIR-ATR and GPC analyses, ensuring the preservation of the original polymer's integrity during physical recycling. [ABSTRACT FROM AUTHOR]

Ecological materials have been implemented in different industrial sectors due to their good performance as thermal insulators and the fact that they are 100% natural, recyclable, and biodegradable, contributing to environmental sustainability. The main objective of this article is to compare the thermal conductivity coefficients of three natural insulators with that of expanded polystyrene (a non-biodegradable material). Expanded polystyrene is one of the materials which is most often used to maintain cold temperatures in containers built for this purpose in the fishing industry; it is used for this purpose because of its properties, including a light weight and a high thermal insulation capacity and resistance. Almost all insulators have the ecological disadvantage of being environmentally unfriendly materials because they are made up of oil particles, which are not recyclable and are harmful to ecosystems. The natural insulator materials were evaluated and subjected to a drying process to reduce the humidity coefficient; then, the containers were built with an adequate insulation thickness of 25 mm. Three filling tests were carried out (at 100, 70, and 50%) to evaluate the thermal conductivity, using the Mann–Whitney U statistical analysis process to determine insulator differences. The results show that the expanded polystyrene had the lowest thermal conductivity of 0.032 W/m K, followed by the rice husk, which had a value of 0.036 W/m K. Finally, a comparative study of conservation costs was carried out in the different containers built with the natural insulators; the lowest value found was for the expanded polystyrene (COP 159.57 around USD 0.040). This allowed to conclude that rice husk is the material that comes closest to the insulating characteristics of expanded polystyrene. [ABSTRACT FROM AUTHOR]

Employing Expanded PolyStyrene, EPS has become common in the construction industry, however, their compressibility creates complexities in effective stress analysis. In this paper, the compressibility of EPS beads and the overall compressibility of sand–EPS beads mixtures have been evaluated. Drained and undrained one-dimensional compression tests along with CD and CU triaxial tests were performed on the mixtures to evaluate the classic effective stress equation. Modified versions of the effective stress equation were applied to results and pore pressure correction factors were obtained from both data series based on two different effective stress analysis approaches (volume change and shear strength related) and compared. Results showed that the two sets of correction factors are consistent. Therefore, correction factors obtained based on the compressibility parameters of the mixtures can be used in the effective stress analysis of CU triaxial tests. Pore pressure factors obtained from the oedometer data were used to analyze results of CU triaxial tests. It is shown that a better agreement between CD and CU stress path results is obtained when the EPS compressibility is considered, leading to similar effective strength parameters in both conditions. [ABSTRACT FROM AUTHOR]

To explore the cushioning properties of expanded polystyrene (EPS), a novel two‐degree‐of‐freedom mathematical model is proposed with a dynamic nonlinear system and successfully implemented it. The maximum response acceleration of the product was first determined in the novel dynamic mathematical model and used as a parameter for evaluating product damage. Furthermore, a drop test was carried out to verify the theoretical model and showed good consistency. Based on the correct theoretical model, a number of simulations with different drop heights and thicknesses of the cushion were done to investigate cushioning properties of EPS. The results show that EPS can reduce the maximum response acceleration of the product by more than 20% of the excitation acceleration. Thus, EPS has good cushioning ability and can be used as packaging material to protect products. Finally, the theoretical model was applied to an example application. A new method for constructing the cushioning curve is recommended, which could replace the traditional ASTM D 1596 drop test method. [ABSTRACT FROM AUTHOR]

Expanded polystyrene (EPS) is a major component of plastic debris in the environment, including coastal and littoral zones. EPS is widely used in various industries including fish farming and aquaculture, which poses a serious potential threat not only to cultured hydrobionts but also to all living organisms, including humans. This paper presents the results of experimental studies on the effects of EPS (0.024 m2/L) on marine mollusks Mytilus trossulus and Tegula rustica, which are typical inhabitants of the upper littoral of Peter the Great Bay (Sea of Japan), belonging to different systematic groups and differing in the type of nutrition. The results of biochemical marker analysis showed the development of oxidative stress processes. Thus, increasing malondialdehyde content relative to control values was registered in the digestive glands of M. trossulus and T. rustica. In the cells of the digestive glands of M. trossulus, integral antioxidant activity decreased more than 1.5 times compared with that of the control. The change in the concentration of protein carbonyls was unchanged in M. trossulus, whereas in T. rustica, there was a 1.5-fold increase. EPS exposure also resulted in significant DNA damage in the studied mollusks—the damage level increased 2.5-fold in M. trossulus and 1.5-fold in T. rustica relative to the control, indicating the genotoxic potential of EPS litters. [ABSTRACT FROM AUTHOR]

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Plastics represent an integral part of our everyday lives, with various functions from packaging materials to insulation layers in our buildings. Pure expanded polystyrene (EPS) is a good example of a fully recyclable material. However, once polluted with other materials or substances, EPS becomes a serious environmental burden. In this work, waste EPS for the production of greener building composites with balanced properties and utility value was investigated. Natural aggregate (2/4 mm) was substituted with corresponding fractions of a thermoplastic alternative in portions of 25, 50, 75, and 100 vol.%. The comprehensive experimental investigation evaluated physical and mechanical properties, heat transport and accumulation, and water absorption characteristics. Due to the uniformly distributed plastic particles in the hardened cement-based matrix, the data revealed an important reduction in the dead weight of produced mortars, which also reduced thermal conductivity by up to 47%. On one hand, lightweight mortars showed partially reduced mechanical resistivity; on the other hand, the EPS bead-modified structure turned out to be effective in liquid water transport reduction.

The purpose of this paper is to consider three aspects of the use of polystyrene as an effective heat-insulating material in three-layer load-bearing and enclosing structures of reinforced concrete residential buildings. The first aspect is related to the dependence of the enclosure heat transfer resistance degree on the method of combining expanded polystyrene with stone structural materials. For example, prefabricated expanded polystyrene concrete blocks for the construction of walls of low and medium-rise buildings and cast-in-situ expanded polystyrene concrete poured into the voids of the well brickwork in high-rise buildings. It is shown that the layer-by-layer application of pure expanded polystyrene and the concrete layers protecting it multiplies the degree of thermal insulation of the enclosing structure while retaining its strength and equal consumption of raw materials. The second aspect is associated with the fire resistance of reinforced concrete load-bearing and enclosing structures of residential buildings. A sufficient degree of fire resistance when protecting expanded polystyrene with cast-in-situ reinforced concrete layers is shown using examples. The third aspect shows the feasibility of using outer three-layer reinforced concrete walls with polystyrene insulation for panel heating of the buildings.

Abstract To explore the cushioning properties of expanded polystyrene (EPS), a novel two‐degree‐of‐freedom mathematical model is proposed with a dynamic nonlinear system and successfully implemented it. The maximum response acceleration of the product was first determined in the novel dynamic mathematical model and used as a parameter for evaluating product damage. Furthermore, a drop test was carried out to verify the theoretical model and showed good consistency. Based on the correct theoretical model, a number of simulations with different drop heights and thicknesses of the cushion were done to investigate cushioning properties of EPS. The results show that EPS can reduce the maximum response acceleration of the product by more than 20% of the excitation acceleration. Thus, EPS has good cushioning ability and can be used as packaging material to protect products. Finally, the theoretical model was applied to an example application. A new method for constructing the cushioning curve is recommended, which could replace the traditional ASTM D 1596 drop test method.

The work aims to analyze the effect of partial replacement of coarse aggregate by expanded polystyrene (EPS) in the production of hollow blocks, a type of concrete block. Substitution levels, by volume, of 0% (reference), 5%, 10%, 15%, 20%, and 25% were tested. The following tests were performed: granulometric composition, specific mass, unit mass, surface analysis tests, absorption, mass determination, dimensional analysis and compressive strength. Regarding surface analysis, the hollow blocks showed satisfactory results. As for water absorption, the blocks performed similarly to the reference blocks with small variations in the results. As for its mass and dimensional variability, the insertion of EPS did not promote significant changes. All specimens with substituted EPS contents met the requirements regarding the blocks' compressive strength. From an environmental point of view, the replacement of EPS meets the requirements of the block standard, contributing to its removal from the environment.

Packaging represents a significant source of all polymer waste produced in the world. Thus, improving recycling methods is essential to achieve an environmentally sustainable condition since the volume of produced polymer and of related waste has grown. Expanded polystyrene (EPS) foam is a thermoplastic with important performance of properties such as thermal isolation and absorption of mechanical energy that allow large application in packaging and other segments. However, the EPS recycling is a challenger due to its low density and poor properties. The rubber incorporation to the recycled EPS is an alternative for the toughening of the polymer matrix as well as improving its mechanical properties. In present study, EPS waste from electric and electronic products packaging was treated by three distinct methods for polymer densification and after it was thermo‐mechanically processed by extrusion with variable content of ground tire rubber (GTR) and compatibilizer agent styrene‐butadiene‐styrene (SBS) copolymer to produce compatibilized and toughened PS/rubber blends. Mechanical, thermal and rheological properties of materials were evaluated by different analyses. The incorporation of rubber to the recycled EPS has significantly improved the mechanical properties of the material and the presence of the SBS agent was effective to compatibilize the PS/rubber blends. Therefore, the preparation of compatibilized PS/rubber blends showed to be a way to the mechanical recycling of EPS and rubber tires waste. [ABSTRACT FROM AUTHOR]

This study focuses on the reduction of the environmental impact of plastic waste and the valorisation of vegetal wastes produced annually from date palms. This paper presents an experimental study on the manufacturing of composite panels based on date palm leaflets, DPL, and expanded polystyrene wastes were carried out. Hot compression process was proposed with the aim of improving the composite manufacturing techniques previously released by the team using a cold compression process. Three composites were studied with the weight fraction (wt.%) of 70, 75 and 80 of the DPL as a reinforcement. The weight fraction of expanded polystyrene is respectively 30, 25 and 20 wt.%. Physical and mechanical characterizations of biocomposites were performed with the reinforcement size between 0.315 mm and 0.5 mm. The result shows that the composite panels have a low density between 414 and 511 kg/m3 . The composite panels showed an improved maximum stress and flexural modulus that can reach 6.18 MPa and 13.5 MPa respectively. These values are comparable to the literature values such as Medium Density Fibreboard (MDF) (13.5-25 MPa) and the Durian Peel and Coconut Coir (DPCC) particleboards (0.8-22.4 MPa), (0.7-43 MPa). However, the water absorption result ranging from 77 to 95 % shows that the studied composite panels are sensitive to moisture and exhibit high moisture uptake percentage thus limits their possibility of use in moist condition. [ABSTRACT FROM AUTHOR]

Unresponsible plastic production and consumption are a major threat to the environment. Plastic valorization is introduced to create a circular economy to intervene in the utilization of plastic waste. Here we utilized expanded polystyrene waste as a functional coating for the cotton fabrics using spray coating methods. Polystyrene was dissolved in toluene and added with ZnO particle. The coating process is facile, and the chemicals are low-cost from the local market. The coated fabrics show a superhydrophobic surface. The highest water contact angle was shown by 3 layers of coated canvas cotton fabric with 15 s coating duration of 150.02°, whereas the oil droplet was quickly absorbed by the fabric. The ZnO EPS coated canvas cotton fabric was used as a membrane separation for the oil–water mixture either in a continuous or batch system. The oil permeability was 7.63 g m−2 s−1 for 3 layers and 15 s coating duration. The continuous system of the membrane module (3 layers, 15 s coating duration) shows 77.14% high separation efficiency of the oil spill. As batch systems, the bottom side of the boat was covered with ZnO-EPS coated canvas cotton fabric (3 layers, 15 s coating duration) and then run across the oil spill. The boat separates the oil spill with a relatively high separation efficiency of 80.06%. This coated fabric made of EPS waste is promising for advanced materials and wastewater treatment. [ABSTRACT FROM AUTHOR]

The utilization of expanded polystyrene (EPS) beads in semi-lightweight concrete (SLC) intended for repair and building applications has gained great attention in recent years. This study examines the effect of mix design parameters including binder content, water-to-binder ratio (w/b), EPS content, and silica fume (SF) additions on the mechanical properties and durability of SLC mixtures. The experimental program was carried out following the Taguchi approach for four parameters, each having three levels, to produce an L9 orthogonal array. The performance criteria under investigation were the superplasticizer demand, density, compressive strength, splitting tensile strength, ultrasonic pulse velocity, water absorption, sorptivity, and abrasion resistance. Test results showed that the w/b and EPS content were the most contributing parameters that altered the SLCs performance. The multi-response optimization method (TOPSIS) revealed that superior performance could be achieved using a binder content of 375 kg/m3, a w/b of 0.45, an EPS content of 3 kg/m3, and a SF replacement rate of 8%. The mix design parameters were utilized to create multivariate regression models to predict the SLCs mechanical and durability properties. Such data can be of particular benefit to engineers seeking the use of lightweight materials for sustainable construction with optimized durability and a reduced cement carbon footprint. [ABSTRACT FROM AUTHOR]

Computer simulations are used to assess the impact of thermal insulation on the transfer of heat and moisture in the exterior walls of residential buildings. The effects of internal and external thermal insulation on a room in a terraced family house are compared using the COMSOL Multiphysics software package, evaluating the influence of the placement of expanded polystyrene thermal insulation on the distribution of temperature and moisture in the external wall while monitoring the indoor air temperature during the heating and cooling modes. The internal thermal insulation is more efficient in terms of room heating, while the external insulation is preferable in reducing the risk of the condensation water vapor within the wall. The efficiency of heating the room at 20°C increased by 12% when internal thermal insulation was added to the walls, compared to heating without insulation. The maximum value of relative humidity in the critical wall section decreased by 10% when external thermal insulation was added. Implementing internal thermal insulation needs the right choice of insulation material and its installation to prevent air leakage. The results suggest that the proper selection of the placement of the thermal insulation is critical for optimizing the thermal performance and reducing moisture-related problems in residential buildings.