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Developing a biobased chemical industry that copes with the current environmental challenges relies on understanding the influence of the different stages of the value chain on economic and environmental performance. This paper investigates the use of a life cycle optimization framework to assess trade-offs between environmental and economic criteria for designing supply chains for biobased polyethylene terephthalate as a case study. A multi-objective optimization model was formulated to account for the environmental impacts (through life cycle assessment) and total costs (through life cycle costing) of the case study. High environmental priority (w = 0.9) in the design of the supply chain resulted in environmental gains (in 8 out of 9 midpoint indicators) with low increments (

This paper describes a statistical and mathematical approach to optimize the mechanical properties of a wood plastic composite with Polyethylene Terephthalate (PET) as polymeric matrix. Wood plastic composite are materials that consist of a primary continuous polymer phase, where a secondary filler dispersed phase is embedded, the filler generally is wood fibers or sawdust. The slack variable approach in mixture experiments, consist in selecting a component of the mixture as slack variable, to subsequently design and analyze the experiment in terms of the remaining components. With the experimental design information three slack variable model were fit. Using response surface graphs, we show how different compositions modify the mechanical properties of wood plastic composite. Besides, by the desirability function, the optimal formulation of the compound that simultaneously maximizing the mechanical properties of wood plastic composite, was obtained. Finally, the components proportions that provides the best tensile, flexural and compression strength are presented.

The composition of waste in Jambi City is dominated by plantation waste and plastic waste, if not managed properly, it can have a negative impact on the environment. There is a need for alternatives to processing plastic waste and plantation waste, one of which is the catalytic cracking process to produce alternative fuels. The catalyst used is petroleum refining industry waste that can be reused. This study aims to analyze the characteristics of FCC (Fluid Catalytic Cracking) catalysts and the effect of the ratio of Polyethylene Terephthalate (PET) plastic waste and Oil Palm Empty Fruit Bunches (OPEFB) on the percentage of products produced. The experimental design used in this study was a Complete Randomized Design (RAL) with variations in the ratio of PET plastic : oil palm empty fruit bunches, namely 1:0, 1:1, 1:2, and 1:3 at a temperature of 450°C and a time of 40 minutes. The results of the analysis showed that spent FCC catalysts were predicted to contain zeolite Y (rich in silica) which had a pore structure of different sizes, while the ratio of PET plastic waste and oil palm empty fruit bunches had a significant effect on the percentage of cracking liquid, charcoal, and gas. The 1:3 ratio treatment resulted in the highest percentage of cracking oil and charcoal at 27.85% and 34.41%. While the percentage of gas was the highest in the 1:0 treatment, which was 82.12%. Keywords: catalytic cracking, polyethylene terephthalate, plastic waste, biomass, empty bunches of palm oil, catalyst spent FCC

Synthetic plastics, like polyethylene terephthalate (PET), have become an essential part of modern life. Many of these products are remarkably persistent in the environment, and the accumulation in the environment is recognised as a major threat. Therefore, an increasing interest has been focusing on the screening for organisms able to degrade and assimilate the plastic. Ideonella sakaiensis originally isolated from a plastisphere has been reported as a bacterium that was solely thriving on the degradation on PET films. The processes affected by the presence of PET and its monomeric substances terephthalic acid, ethylene glycol, ethyl glycolate, and sodium glyoxylate monohydrate were elucidated by analysis of differential protein expression. The exposure of PET and its monomers induced the MHETase and affect two major pathways: the TCA cycle and the β-oxidation pathway. The increased expression of proteins directly or indirectly involved in these pathways suggests their underlying importance in the degradation of PET by I. sakaiensis since these proteins are mechanistically supporting the enzymes involved in the degradation of PET and its monomers.

The annual production of plastic waste is a serious ecological problem as it causes substantial pollution of the environment. Polyethylene terephthalate, a material usually found in disposable plastic bottles, is one of the most popular material used for packaging in the world. In this paper, it is proposed to recycle polyethylene terephthalate waste bottles into benzene-toluene-xylene fraction using a heterogeneous nickel phosphide catalyst formed in situ during the polyethylene terephthalate recycling process. The catalyst obtained was characterized using powder X-ray diffraction, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy techniques. The catalyst was shown to contain a Ni2P phase. Its activity was studied in a temperature range of 250–400 °C and a H2 pressure range of 5–9 MPa. The highest selectivity for benzene-toluene-xylene fraction was 93% at quantitative conversion.

Fabrication of self-reinforced polyethylene terephthalate (PET) has been achieved through the in situ generation of PET fibrils via a spun bond process. The reinforcement fibrils created from the PET with higher Tm are made from a unique in situ processing method. As a result, the fibrils are well dispersed and distributed in the lower Tm PET matrix. The high degree of molecular similarity affords perfect interfaces between the matrix and dispersed phase, leading to excellent stress transfer from the matrix to the dispersed fibrils. While the extremely large interfaces from the nanofibrillation process can maximize the advantage of the excellent molecular similarity of the self-reinforced polymeric composites, few studies have been conducted to research nanofibrillar self-reinforced polymeric composite systems. Hence, as a proof of concept, this work provides new insight into an approach for developing a self-reinforced polymeric system with a nanofibrillation process. This process increases the tensile strength of PET composites by up to 15% compared to composites made by a simple blending process and 47% higher than neat PET. Furthermore, extensional viscosity measurements show a strain-hardening behavior in the fibrillated PET composites not observed in the neat PET and showed minimal behavior in un-fibrillated PET composites. The foam process results reveal that the presence of PET fibrils in PET improves the expansion ratio as well as the cell density of the PET composites. Specifically, compared to the PET composite foams without the fibrillation process, fibrillated PET composite foams showed up to 3.7 times higher expansion ratios and one to two orders of magnitude higher cell densities. In thermal conductivity measurements, fibrillated PET composite foams achieved thermal conductivity of as low as 0.032 W/mK.

Mestrado Bolonha em Management The production of fossil-based plastics can be credited with the usage of around 4% to 8% of oil and gas globally, with current trends pointing to upwards of 20% in 2050, making this material a threat to the worsening of greenhouse emissions and global warming (Hopewell et al., 2009; Rhodes, 2018). Within this problematic, the pollution created by single-use bottles has received a lot of regulatory oversight, with an increasing number of methods for the reduction of said waste having been developed in response to said regulations. One of the most popularly used materials within this market is Polyethylene terephthalate (PET), with Recycled Polyethylene terephthalate (rPET) standing out as the most economically and environmentally sustainable alternative. With the introduction of regulations for the quantity of recycled content in PET bottles, several markets have been affected, though little regard has been given to the consequences of setting benchmarks that may be “overly prescriptive and market intrusive” (Ilie & Jurconi, 2019), with the market for rPET currently suffering from a supply-demand imbalance that has led to claims of economically unsustainable regulations. The goal of this research was to assess the degree to which the rPET level in the current legislation, and superior levels of rPET content, affects the financial viability of products that use said materials. This being done through a financial viability analysis of introducing increasing amounts of this material in an existing, established olive-oil product. It was found that for 30%, 50%, and 75% rPET content, financial viability could be reached for this specific unit in a static setting, this being concluded through an analysis of the willingness-to-pay (WTP) of consumers, measured by form of a questionnaire, and translated into the price sensitivity of demand of the three aforementioned product variants. A produção de plásticos com origem fóssil é responsável pela utilização de 4% a 8% do gás e petróleo produzido globalmente, com as atuais tendências a apontarem para que este valor atinja 20% em 2050, fazendo deste material, uma ameaça para a exacerbação da emissão de gases com efeito de estufa e do aquecimento global (Hopewell et al., 2009; Rhodes, 2018). Dentro desta problemática, a poluição criada por garrafas descartáveis recebeu particular enfoque legislativo, com o número de métodos para a redução de tais efeitos tendo se multiplicado em resposta a tais regulamentações. Um dos materiais mais utilizados é o Polietileno tereftalato (PET), com o Polietileno tereftalato reciclado (rPET), a destacar-se como a alternativa sustentável com maior viabilidade económica. Com a recente criação de regulamentações para a implementação de conteúdo reciclado nas garrafas PET, vários mercados foram afetados, no entanto, as consequências do estabelecimento de metas que podem ser demasiado prescritivas e intrusivas no funcionamento destes mercados, foi pouco considerada pelos reguladores (Ilie & Jurconi, 2019), com o mercado do rPET a sofrer, neste momento, de um desequilíbrio entre a procura e a oferta que tem levado a reivindicações de que estas regulamentações são economicamente insustentáveis. O objetivo deste estudo foi determinar o impacto que o nível de rPET definido na atual legislação, bem como níveis superiores, afetam a viabilidade financeira de produtos que utilizam esses mesmos materiais. Isto foi feito através da análise da viabilidade financeira de introduzir quantidades ascendentes deste material num produto existente de azeite. Foi descoberto que, para 30%, 50% e 75% de conteúdo rPET, a viabilidade financeira é atingida para a unidade estudada numa perspetiva estática, tendo sido isto concluído através da análise da disposição em pagar (DAP) dos consumidores, medida através de um questionário e subsequentemente transformado na sensibilidade de preço da procura das três variantes referidas. info:eu-repo/semantics/publishedVersion

Teniendo en cuenta que, al momento de la fabricación de una mezcla asfáltica se implementan elevadas cantidades de materiales pétreos no renovables, causando modificaciones irreparables para el medio ambiente especialmente en la calidad del aire, debido a esto se propone llevar a cabo una o varias alternativas que puedan llegar a sustituir algunos de los materiales convencionales en las mezclas asfálticas, implementando materiales como residuos plásticos también definidos como Tereftalato de Polietileno (PET) y escorias negras de horno de arco eléctrico (EAF), con la premisa de que estos son desperdiciados en gran proporción por las industrias a nivel nacional e internacional y pueden llegar a ser reutilizados para beneficios medio ambientales. Con base en lo anterior el presente proyecto cuenta con 3 fases definidas como: Primer fase enfocada en la caracterización de los agregados realizando las pruebas de laboratorio que estos requieren según las especificaciones de construcción de carreteras INVIAS 2022; Segunda fase enfocada en la elaboración del diseño de la mezcla asfáltica convencional teniendo así la realización de 4 briquetas por cada porcentaje de asfalto (4, 4.5, 5, 5.5 y 6%), permitiendo determinar el porcentaje óptimo para el diseño de mezcla asfáltica modificada; Tercera fase enfocada en la elaboración del diseño de la mezcla asfáltica modificada, con la previa determinación del porcentaje óptimo de asfalto, la presente fase contó con 5 métodos diseñados los cuales generan variación en la sustitución de porcentaje de Tereftalato de Polietileno (PET) en el cemento asfaltico y de escorias negras de horno de arco eléctrico (EAF) en la sustitución de materiales granulares, teniendo como finalidad la determinación de la dosificación óptima desde la perspectiva mecánica de la estabilidad y flujo de mezclas en caliente de gradación intermedia modificadas con materiales reciclados Tereftalato de Polietileno (PET) y escorias negras de horno de arco eléctrico (EAF). Se implementará la metodología Marshall para valorar el desempeño de una mezcla asfáltica tipo MDC-19 convencional comparándola con la mezcla modificada. Se presento la caracterización de los agregados gruesos y finos de la mezcla asfáltica densa en caliente, evaluando cada uno de los requisitos de los agregados estandarizados por el Instituto Nacional de Vías (INVIAS). Luego de realizar la caracterización se elaboraron una serie de briquetas (40 briquetas) para determinar el flujo (mm) y estabilidad (kN) de la mezcla óptima del diseño implementado el equipo Marshall. Taking into account that, at the time of manufacturing an asphalt mix, high amounts of non-renewable stone materials are implemented, causing irreparable changes to the environment, especially in air quality, due to this, it is proposed to carry out one or several alternatives. that can replace some of the conventional materials in asphalt mixes, implementing materials such as plastic waste also defined as Polyethylene Terephthalate (PET) and black slag from the electric arc furnace (EAF), with the premise that these are wasted in a large proportion by industries at a national and international level and can be reused for environmental benefits. Based on the above, this project has 3 phases defined as: First phase focused on the characterization of the aggregates, carrying out the laboratory tests that they require according to the INVIAS 2022 road construction specifications; Second phase focused on the elaboration of the design of the conventional asphalt mix, thus having the realization of 4 briquettes for each percentage of asphalt (4, 4.5, 5, 5.5 and 6%), allowing to determine the optimal percentage for the modified asphalt mix design. ; Third phase focused on the development of the design of the modified asphalt mix, with the previous determination of the optimal percentage of asphalt, this phase had 5 designed methods which generate variation in the substitution of the percentage of Polyethylene Terephthalate (PET) in the asphalt cement and black slag from the electric arc furnace (EAF) in the substitution of granular materials, with the purpose of determining the optimal dosage from the mechanical perspective of the stability and flow of hot mixtures of intermediate gradation modified with recycled materials Polyethylene terephthalate (PET) and black slag from electric arc furnace (EAF). The Marshall methodology will be implemented to assess the performance of a conventional MDC-19 type asphalt mix by comparing it with the modified mix. The characterization of the coarse and fine aggregates of the hot dense asphalt mix was presented, evaluating each one of the requirements of the aggregates standardized by the National Institute of Roads (INVIAS). After carrying out the characterization, a series of briquettes (40 briquettes) were prepared to determine the flow (mm) and stability (kN) of the optimal mixture of the design implemented by the Marshall equipment. Ingeniero Civil Pregrado

Extensive plastic production has become a serious environmental and health problem due to the lack of efficient treatment of plastic waste. Polyethylene terephthalate (PET) is one of the most used polymers and is accumulating in landfills or elsewhere in nature at alarming rates. In recent years, enzymatic degradation of PET by Ideonella sakaiensis PETase (IsPETase), a cutinase-like enzyme, has emerged as a promising strategy to completely depolymerize this polymer into its building blocks. Here, inspired by the architecture of cutinases and lipases homologous to IsPETase and using 3D structure information of the enzyme, we rationally designed three mutations in IsPETase active site for enhancing its PET-degrading activity. In particular, the S238Y mutant, located nearby the catalytic triad, showed a degradation activity increased by 3.3-fold in comparison to the wild-type enzyme. Importantly, this structural modification favoured the function of the enzyme in breaking down highly crystallized (~31%) PET, which is found in commercial soft drink bottles. In addition, microscopical analysis of enzyme-treated PET samples showed that IsPETase acts better when the smooth surface of highly crystalline PET is altered by mechanical stress. These results represent important progress in the accomplishment of a sustainable and complete degradation of PET pollution.

This study proposes reusing post-consumer soil-filled PET (polyethylene terephthalate) bottles as a novel soil reinforcing element by conducting a laboratory-scale experimental investigation. The concept is that the polymer bottle walls act to confine the interior soil so that the bed behaves somewhat like a brick-built load spreading zone. The soil-filled bottles were horizontally laid within the soil bed in the desired depth and then the backfilling was performed. The effect of different parameters such as depth of placement, width and height of the soil-filled, bottle-reinforced mattress are studied under static plate load testing. Test results revealed that the bottle-reinforced bed is highly rigid, delivering very high bearing capacities at small soil displacements. Optimum depth of placement, width and height of the bottle-reinforced zone were respectively about 0.03B, 2.17B and 0.57B. An improvement in bearing capacity ratio (BCR) by a factor of ∼3, and up to 80% reduction in soil settlement, were observed. The proposed method of soil reinforcement can be an excellent and relatively economic alternative to conventional geosynthetic reinforcement, as well as delivering geotechnical and environmental advantages.

Studies on the degradation process of waste polyethylene terephthalate (PET) have become increasingly mature, but there are relatively few studies on the separation of degradation products. The products contain many components and the separation of which is difficult. Therefore, the study on phase equilibrium thermodynamics of bis-2-hydroxyethyl terephthalate (BHET) is of great theoretical significance and practical value to provide basic data for the BHET crystallization separation. In this work, the degraded products were purified and characterized. The solubility of BHET in methanol, ethanol, ethylene glycol, water and the mixture of ethylene glycol+water were determined by static method. The experimental results were correlated with different models, such as IS model, λh equation, Apelblat equation and NRTL model. Based on the Van't Hoff equation, the mixing Gibbs energy, enthalpy and entropy were calculated. From this work, the basic data which can be used to guide the crystallization process of BHET were obtained, including solubility data, correlation model and thermodynamic properties

Electron transport layers (ETLs) play a fundamental role in perovskite solar cells (PSCs) through charge extraction. Here, we developed flexible PSCs on 12 different kinds of ETLs based on SnO2. We show that ETLs need to be specifically developed for plastic substrates in order to attain 15% efficient flexible cells. Recipes developed for glass substrates do not typically transfer directly. Among all the ETLs, ZnO/SnO2 double layers delivered the highest average power conversion efficiency of 14.6% (best cell 14.8%), 39% higher than that of flexible cells of the same batch based on SnO2-only ETLs. However, the cells with a single ETL made of SnO2 nanoparticles were found to be more stable as well as more efficient and reproducible than SnO2 formed from a liquid precursor (SnO2-LP). We aimed at increasing the understanding of what makes a good ETL on polyethylene terephthalate (PET) substrates. More so than ensuring electron transport (as seen from on-current and series resistance analysis), delivering high shunt resistances (RSH) and lower recombination currents (Ioff) is key to obtain high efficiency. In fact, RSH of PSCs fabricated on glass was twice as large, and Ioff was 76% lower in relative terms, on average, than those on PET, indicating considerably better blocking behavior of ETLs on glass, which to a large extent explains the differences in average PCE (+29% in relative terms for glass vs PET) between these two types of devices. Importantly, we also found a clear trend for all ETLs and for different substrates between the wetting behavior of each surface and the final performance of the device, with efficiencies increasing with lower contact angles (ranging between ∼50 and 80°). Better wetting, with average contact angles being lower by 25% on glass versus PET, was conducive to delivering higher-quality layers and interfaces. This cognizance can help further optimize flexible devices and close the efficiency gap that still exists with their glass counterparts.

Background: In this study, Near-field electrospinning (NFES) technique used with a cylindrical collector to fabricate a large area permanent piezoelectric micro and nanofibers by a prepared solution. NFES requires a small electric field to fabricate fibers. Objective: The objective of this paper to investigate silver nanoparticle (Ag-NP)/ Polyvinylidene fluoride (PVDF) composite as the best piezoelectric material with improved properties to produced tremendously flexible and sensitive piezoelectric material with pertinent conductance. Method: In this paper we used controllable electrospinning technique based on Near-field electrospinning (NFES)The process parameter for Ag-NP/PVDF composite electrospun fiber based on pure PVDF fiber. A PVDF solution concentration of 18 wt.% and 6 wt.% silver nitrate which is relative to the weight of PVDF wt.% with 1058 µS conductivity fibers have been directly written on a rotating cylindrical collector for aligned fiber PVDF/Ag-NP fibers are patterned on fabricated copper (Cu) interdigitated electrodes were implemented on a thin flexible polyethylene terephthalate (PET) substrate and Polydimethylsiloxane (PDMS) used as a package to enhance the durability of the PVDF/ Ag-NP device. Results: A notable effect on the piezoelectric response has been observed after Ag-NP addition confirmed by XRD characterization and tapping test of Ag-NP/PVDF composite fiber. The morphology of the PVDF/Ag-NP fibers and measure diameter by scanning electron microscopy (SEM) and Optical micrograph (OM), of fiber. Finally, The result shows that diameter of PVDF/Ag-NP fibers up to ~7 μm. The. High diffraction peak at 2θ = 20.5˚ was investigated by X-ray diffraction (XRD) in the piezoelectric crystal β-phase structure. While the electromechanical conversion is found enhance from ~0.1 V to ~1 V by the addition of silver nanoparticles (Ag-NPs) in the PVDF solution. Conclusion: In conclusion, we can say that confirmed and validated the addition of Ag-NP in PVDF could enhance the piezoelectric property by using NFES technique with improved crystalline phase content can be useful for a wide range of power and sensing applications like biomedical devices and energy harvesting, among others.

This study demonstrates the direct hydrogenation of polyethylene terephthalate (PET) dissolved in 1,1,1,3,3,3-hexafluro-2-propanol to environmentally friendly polyester polyethylene-1,4-cyclohexanedicarboxylate (PECHD) using a Vulcan XC-72 supported Rh-Pt bimetallic catalyst synthesized via a polyol method. The hydrogenation of PET was promoted by RhOx species present on the catalyst support surface which was generated using the polyol synthesis method. As compared to the monometallic Rh catalyst, the Rh-Pt bimetallic catalyst was found to be superior for hydrogenation of PET. This superiority was attributed to the strong aromatic ring adsorption ability of Rh working in synergy with an increased H2 spillover by Pt. At a H2 pressure of 6.89 MPa and 50 °C for 60 min, complete hydrogenation of PET to PECHD was achieved over the Rh-Pt bimetallic catalyst possessing theoretical Rh and Pt metal loadings of 2.5 wt% each. PECHD was found to be recovered to a very high extent using the compressed CO2 anti-solvent technique after hydrogenation of PET.

Prevention of bacterial adhesion is a way to reduce and/or avoid biofilm formation, thus restraining its associated infections. The development of repellent anti-adhesive surfaces, such as superhydrophobic surfaces, can be a strategy to avoid bacterial adhesion. In this study, a polyethylene terephthalate (PET) film was modified by in situ growth of silica nanoparticles (NPs) to create a rough surface. The surface was further modified with fluorinated carbon chains to increase its hydrophobicity. The modified PET surfaces presented a pronounced superhydrophobic character, showing a water contact angle of 156° and a roughness of 104 nm (a considerable increase comparing with the 69° and 4.8 nm obtained for the untreated PET). Scanning Electron Microscopy was used to evaluate the modified surfaces morphology, further confirming its successful modification with nanoparticles. Additionally, a bacterial adhesion assay using an Escherichia coli expressing YadA, an adhesive protein from Yersinia so-called Yersinia adhesin A, was used to assess the anti-adhesive potential of the modified PET. Contrarily to what was expected, adhesion of E. coli YadA was found to increase on the modified PET surfaces, exhibiting a clear preference for the crevices. This study highlights the role of material micro topography as an important attribute when considering bacterial adhesion.

Prevention of bacterial adhesion is a way to reduce and/or avoid biofilm formation, thus restraining its associated infections. The development of repellent anti-adhesive surfaces, such as superhydrophobic surfaces, can be a strategy to avoid bacterial adhesion. In this study, a polyethylene terephthalate (PET) film was modified by in situ growth of silica nanoparticles (NPs) to create a rough surface. The surface was further modified with fluorinated carbon chains to increase its hydrophobicity. The modified PET surfaces presented a pronounced superhydrophobic character, showing a water contact angle of 156° and a roughness of 104 nm (a considerable increase comparing with the 69° and 4.8 nm obtained for the untreated PET). Scanning Electron Microscopy was used to evaluate the modified surfaces morphology, further confirming its successful modification with nanoparticles. Additionally, a bacterial adhesion assay using an Escherichia coli expressing YadA, an adhesive protein from Yersinia so-called Yersinia adhesin A, was used to assess the anti-adhesive potential of the modified PET. Contrarily to what was expected, adhesion of E. coli YadA was found to increase on the modified PET surfaces, exhibiting a clear preference for the crevices. This study highlights the role of material micro topography as an important attribute when considering bacterial adhesion., This work was supported by the ViBrANT project that received funding from the EU Horizon 2020 Research and Innovation Programme under the Marie Sklowdowska-Curie, Grant agreement no 765042 and the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020., info:eu-repo/semantics/publishedVersion

The main topic of the presented work is the evaluation of the in-line viscometer (VIS) operation installed on the industrial line for polyethylene terephthalate (PET) foil production. The tests were performed during the regular operation of the machine, which results from the need to maintain production continuity. Polymer viscosity control is of particular importance in the production of degradable materials and recycled polymers. The processing of PET film is, therefore, a particularly difficult issue due to the presence of both of these problems at the same time. The conducted research had a two-pronged character: assessment of the correct operation of the viscosity measurement system and testing of the effectiveness of reactive additives during the extrusion process. Measurements were carried out with the use of several types of input materials, including recycled blends. The key tests were carried out with the addition of viscosity modifiers. Measurements conducted during the extrusion process confirmed the effectiveness and high sensitivity of the in-line system (VIS), while clear changes in the polymer flow characteristics were observed only after the addition of chain extenders. The in-line measurements revealed that the addition of 1% of the reactive compound increased the viscosity from the initial 150 Pa∙s to over 350 Pa∙s. The most significant increase in viscosity for the additive based on pyromellitic dianhydride (PMDA) confirms the effectiveness of the reactive extrusion method and the suitability of the used measuring. During further analysis, the obtained films were also tested. The results showed no negative effects of the reactive extrusion on the mechanical performance of the foil; however, for recycled materials, the average values of tensile strength and elongation at break have deteriorated. A positive aspect of the use of reactive additives was the greater uniformity of mechanical properties. For some materials, there was a significant increase in the haze factor (transparency), which should be considered a disadvantage.

The building and construction industry is a key sector behind the ecological transition in that it is one of the main responsible factors in the consumption of natural resources. Thus, in line with circular economy, the use of waste aggregates in mortars is a possible solution to increase the sustainability of cement materials. In the present paper, polyethylene terephthalate (PET) from bottle scraps (without chemical pretreatment) was used as aggregate in cement mortars to replace conventional sand aggregate (20%, 50% and 80% by weight). The fresh and hardened properties of the innovative mixtures proposed were evaluated through a multiscale physical-mechanical investigation. The main results of this study show the feasibility of the reuse of PET waste aggregates as substitutes for natural aggregates in mortars. The mixtures with bare PET resulted in less fluid than the specimens with sand; this was ascribed to the higher volume of the recycled aggregates with respect to sand. Moreover, PET mortars showed a high tensile strength and energy absorption capacity (with Rf = 1.9 ÷ 3.3 MPa, Rc = 6 ÷ 13 MPa); instead, sand samples were characterized by a brittle rupture. The lightweight specimens showed a thermal insulation increase ranging 65–84% with respect to the reference; the best results were obtained with 800 g of PET aggregate, characterized by a decrease in conductivity of approximately 86% concerning the control. The properties of these environmentally sustainable composite materials may be suitable for non-structural insulating artifacts.

Tese de doutoramento em Chemical and Biological Engineering, Spread of infections is a growing concern in the healthcare sector, leading to high medical expenses, antibiotic resistance and even death. One recently explored alternative to reduce the spread of infections is by using anti-adhesive surfaces. Different strategies can be used to develop such antiadhesive surfaces, as for example manipulating the surface wettability. Polyethylene terephthalate (PET) is one of the most widely used polymers in the healthcare sector. Although it provides advantages including excellent chemical, physical and mechanical properties and biocompatibility, its anti-adhesive properties still need to be improved. In this thesis, PET surface was modified to improve its antiadhesive properties using three different approaches, namely (1) rendering the surface hydrophilic by chemically grafting a natural polysaccharide (gum Arabic); (2) rendering the surface hydrophilic by UV polymerization of acrylates (sodium acrylate and 3-sulfopropyl acrylate potassium salt); and (3) rendering the surface superhydrophobic by in situ growth of nanoparticles and low surface energy molecules. Determination of contact angle, AFM, FTIR, XPS and UV-VIS spectrophotometer analysis on treated surfaces clearly showed that the abovementioned modifications were successfully accomplished. The hydrophilic modified PET surfaces were found to be anti-adhesive, while the superhydrophobic one was contrarily promoting bacterial adhesion which was thought to be due to bacterial orientation on the ununiformly structured surface, when evaluated for their anti-adhesiveness against an Escherichia coli expressing YadA (Yersinia enterocolitica adhesin) herein used as a model adhesive microorganism. Finally, the performance of the modified materials was assessed regarding crystal formation using artificial urine. Although, the modified materials did not perform better than the unmodified PET regarding crystal formation, the gum Arabic modified PET and the acrylate modified PET could still be useful for intermittent catheterization due to their anti-adhesive properties, besides exhibiting a great potential also for other applications, such as diagnosis tools., A propagação de infeções é uma preocupação crescente no setor da saúde, pois acarreta elevados custos para o setor hospitalar, bem como potencia o aumento da resistência a antibióticos e pode mesmo levar à morte da pessoa infetada. Uma alternativa recentemente explorada para reduzir a propagação de infeções é o uso de superfícies anti-adesivas. Para desenvolver estas superfícies podem ser usadas diferentes estratégias, como por exemplo manipular a molhabilidade da superfície. O polietileno tereftalato (PET) é um dos polímeros mais utilizados no setor de saúde. Embora apresente vantagens como excelentes propriedades químicas, físicas, mecânicas e biocompatibilidade, as suas propriedades anti-adesivas ainda precisam ser melhoradas. Nesta tese, a superfície do PET foi modificada para melhorar as suas propriedades anti-adesivas, usando três abordagens diferentes, nomeadamente (1) tornando a superfície hidrofílica através do enxerto químico de um polissacarídeo natural (goma arábica); (2) tornando a superfície hidrofílica através da fotopolimerização de acrilatos (acrilato de sódio e sal de potássio de acrilato de 3-sulfopropilo); e (3) tornando a superfície superhidrofóbica pelo crescimento in situ de nanopartículas e moléculas de baixa energia superficial. As superfícies tratadas foram caracterizadas por ângulo de contato, AFM, FTIR, XPS e análise por espectrofotometria UV-VIS, evidenciando claramente que as modificações acima mencionadas foram realizadas com sucesso. As superfícies hidrofílicas do PET modificado demonstraram propriedades antiadesivas, contrariamente à superfície super-hidrofóbica, que promoveu a adesão bacteriana, pensandose ser devido à orientação das bactérias na superfície irregular do PET, quando foi efetuado o teste de adesividade usando uma Escherichia coli expressando YadA (adesina Yersinia enterocolitica), como um microrganismo adesivo modelo. Por fim, avaliou-se o desempenho dos materiais modificados quanto à formação de cristais, utilizando urina artificial. Embora os materiais modificados não tenham tido um desempenho significativamente melhor que o PET virgem quanto à formação de cristais, o PET modificado com goma arábica e o PET modificado com acrilatos pode ser extremamente útil para o cateterismo intermitente devido às suas propriedades anti-adesivas, para além de apresentar um enorme potencial para outras aplicações, como a utilização em kits de diagnóstico., This project has received funding from the European Union`s Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement No. 765042.

Multi-material layered plastic films are used in the food packaging industry due to their excellent properties; however they cannot be mechanically recycled. In this study, a two-stage hydrothermal liquefaction (HTL) process is proposed and tested for chemical recycling of a two-layer film made of LLDPE-PET. Experimental results showed that after a first subcritical stage at 325 °C, 94% of terephthalic acid (TPA) is recovered from the PET fraction as a solid and 47% of ethylene glycol in the aqueous phase. The unconverted PE was then used as feedstock for a subsequent supercritical HTL stage at 450 °C for 90 min, achieving mass yields of 47% and 29% in a naphtha-gasoline oil and in an alkane-rich gas, respectively. In conclusion, this work proved that a sequential HTL procedure can be used for chemical recycling of multilayer plastics, allowing the recovery of PET monomers to be recycled back to the PET industry and a paraffinic oil and hydrocarbon-rich gas phase that could be used as feedstock for steam cracking to produce virgin materials.

Plastics have become integral parts of modern life, but the indiscriminate disposal of non-biodegradable plastic waste has created an environmental crisis worldwide. In this issue of Chem Catalysis, Luca and co-workers report a groundbreaking, organocatalyzed electroreductive approach to depolymerizing polyethylene terephthalate back to its monomers ethylene glycol and terephthalic acid. Submitted/Accepted version

Unter Xenoöstrogenen werden Verbindungen verstanden, welche natürliche Östrogene in ihrer Wirkung imitieren können, jedoch nicht vom menschlichen Körper gebildet werden. Sie binden mit unterschiedlicher Selektivität und Affinität an Östrogenrezeptoren und können dadurch auch gesundheitliche Folgen für den exponierten Organismus bedeuten. Als Bestandteil von Lebensmittelkontaktmaterialien – speziell von Kunststoffen – können derartige Verbindungen in das Füllgut beziehungsweise in das Lebensmittel migrieren und so durch die Ernährung vom Menschen aufgenommen werden. Daraus ergibt sich die Notwendigkeit, Lebensmittelkontaktmaterialien auf ihre potenzielle östrogene Aktivität zu untersuchen und auf ihre Lebensmitteltauglichkeit hin zu bewerten. Der Yeast Estrogen Screen (YES) ist eine etablierte in vitro Methode zur Detektion östrogenaktiver Substanzen in Lebensmittelkontaktmaterialien, wobei diese Substanzen nicht qualitativ analysiert sondern ausschließlich deren potenzielle östrogene Aktivität bestimmt wird. Ziel der Arbeit ist daher die Validierung des Yeast Estrogen Screen (YES) in den Laboratorien des Fachbereichs Verpackungs- und Ressourcenmanagement der Fachhochschule Campus Wien mit den dort verfügbaren Chemikalien und Geräten. Als Validierungsparameter wurden die Wiederholpräzision, die laborinterne Präzision sowie die Robustheit des Yeast Estrogen Screen (YES) untersucht. Als Substanzen wurden Bisphenol A, 4-n-Nonylphenol und 2,4-di-tert-Butylphenol in unterschiedlichen Konzentration für die Validierung herangezogen. Die Wiederholpräzision wurde mit allen dieser drei Verbindungen untersucht. Das definierte Akzeptanzkriterium (Variationskoeffizient 𝑉𝐾≤30%) wurde von Bisphenol A in einer Konzentration von 0,05 mmol/L und von 2,4-di-tert-Butylphenol in einer Konzentration von 2,5 mmol/L erfüllt. Die laborinterne Präzision wurde an verschiedenen Konzentrationen von Bisphenol A untersucht, wobei die durchführende Person und der Tag der Durchführung variiert wurden. Das definierte Akzeptanzkriterium (Variationskoeffizient 𝑉𝐾≤30%) konnte von keiner der analysierten Konzentrationen erfüllt werden. Für die Ermittlung der Robustheit wurde der Volumenanteil des CPRG-Lytikase-Mastermix, welcher am photometrisch gemessenen Farbumschlag beteiligt ist, variiert und die Wiederfindung der Östradiol-Standardkonzentrationen, welche auch zur Erstellung der Kalibriergerade gemessen wurden, ermittelt. Mit abnehmendem Volumenanteil konnte nur für die geringste Östradiolkonzentration (1 nmol/L) eine 100%ige Wiederfindung erreicht werden. Generell konnten wachstumsinhibierende Effekte bei jeweils höheren Konzentrationen der einzelnen Substanzen festgestellt werden, wodurch auch die gemessene östrogene Aktivität beeinflusst wurde. Weiters wurden fünf PET- und sechs HDPE-Proben auf östrogene Effekte hin untersucht. Bei keiner der getesteten Proben wurde eine östrogene Wirkung mittels Yeast Estrogen Screen (YES) festgestellt. Xenoestrogens are compounds able to mimic natural estrogens. They can bind to the human estrogen receptor with different selectivity and affinity and therefore induce adverse effects on the exposed organism. Being part of food contact materials – especially plastics – these compounds might migrate into the packed food and thus be ingested by humans. It is therefore necessary to investigate potential estrogenic effects of these food contact materials. The Yeast Estrogen Screen (YES) is an established in vitro method to detect estrogenic effects. Thus, the aim of this Bachelor thesis is the validation of the Yeast Estrogen Screen (YES) in the setting of the laboratories of the Department of Applied Life Sciences, Section for Packaging and Ressource Management, Packaging Technology and Sustainability, of the Fachhochschule Campus Wien with the chemicals and instruments available. Validation parameters investigated were the repeatability, reproducibility (in-lab precision) as well as the robustness of the Yeast Estrogen Screen (YES), using bisphenol A, 4-n-nonylphenol and 2,4-di-tert-butylphenol in different concentrations. Repeatability was determined by using all of these substances. 0.05 M bisphenol A and 2.5 M 2,4-di-tert-butylphenol delivered results within the established criteria (relative standard deviation ≤ 30 %). In-lab precision was determined by using different concentraions of bisphenol A. None of the concentrations delivered results within the established criteria (relative standard deviation ≤ 30 %). In order to investigate the robustness of the test different volumes of the CPRG-lyticase mastermix (the chromogenic substrate which is measured photometrically) were applied to the estradiol standard concentrations and the recovery rate was determined. With decreasing volume of this mastermix a recovery rate of 100% could only be achieved for the smallest estradiol concentration (1 nmol/L). Growth inhibition of the Saccharomyces cerevisiae cells was observed at higher concentrations of the substances, respectively, which also had an effect on the estrogenicity detected. Furthermore, five PET und six HDPE samples were investigated for their potential estrogenic effects, whereas none of samples tested induced estrogenic effects in the Yeast Estrogen Screen (YES).

The production of hydrogen (H2) from the pyrolysis–catalytic steam reforming of polyethylene, polystyrene (PS) and polyethylene terephthalate waste plastics was investigated using a two-stage reactor. The highest yield of hydrogen (125 mmol/gplastic) was obtained with PS at a catalyst temperature of 900°C and steam input weight hourly space velocity of 7.59 g/(h/gcatalyst) with a 10 wt% nickel/aluminium oxide (Ni/Al2O3) catalyst. Further investigation using PS showed that the process parameters of high catalyst temperature (900°C) and optimised steam input rate significantly increased the yield of hydrogen. Examination of several different catalysts (nickel/aluminium oxide, iron/aluminium oxide, copper/aluminium oxide, cobalt/aluminium oxide) showed that nickel/aluminium oxide had by far the highest catalytic activity and selectivity towards the yield of hydrogen.

Nanostructure wrinkle created by amorphous diamond like carbon (a:DLC) thin films on a flexible Polyethylene Terephthalate (PET) substrate via chemical bath deposition technique was studied in detail. Atomic force microscopy (AFM) image revealed that the nanostructure wrinkle pattern with varying wavelengths from 350 nm to 170 nm are closely spaced and randomly oriented on the PET substrate. Raman spectra analysis showed that the chemical composition i.e., sp2/(sp2 + sp3) bonding ratio in the deposited a:DLC nanostructure wrinkle thin films was varied by changing the sucrose weight percentage in the precursor solution used for a:DLC thin film deposition. The optical band gap energy decreased from 3.17 eV to 2.04 eV for the a:DLC nanostructure wrinkle thin films due to increase the sucrose weight percentage in the precursor solution from 5 to 30 respectively. The disorderness and defect density in the a:DLC nanostructure wrinkle thin films calculated from Raman spectra as well as from Urbach energy calculation. The change in optical transmittance, extinction coefficient, refractive index and optical band gap energy has been discussed in terms of composition and nanostructure wrinkle pattern of the a:DLC thin films.

In this study a comprehensive effort was made to understand the applicability of polyethylene terephthalate (PET) as a construction material. In this regard, PET-fibers of aspect ratio (AR): 25, 50 and 75, and in proportion of: 3%, 6%, 9% and 12%, were used in the construction of concrete specimens. Further, a comparison was made with respect to the impacts of uncoated and granulated blast furnace slag (GBFS)-coated PET-Fs on different properties of concrete. It was observed that concrete specimens with GBFS-coated PET-Fs were having better compressive strength (CS), split tensile strength (STS), flexural strength (FS), workability (W) and density (D), as compared to specimens with uncoated PET-Fs. Moreover, with the increase in proportion of the PET-Fs the negative impacts of the different properties concrete were lesser in case of GBFS-coated PET-Fs. Therefore, the findings of this study are expected to encourage the use of PET-Fs as a construction material.

Plastic waste is increasing exponentially in these unprecedented times induced by pandemic outbreak of COVID-19. Therefore, in this study, efforts were made to assess the usage of plastic waste, in the form of polyethylene terephthalate fibers (PET-Fs), in concrete. Further, to enhance the properties of concrete, the PET-Fs were coated with sugarcane bagasse ash (SBA), which is another industrial bi-product. The PET-Fs were used in different proportion i.e., 3%, 6%, 9% and 12%, and of different aspect ratios (ARs) i.e., 25, 50 and 75, in the concrete specimens. The concrete specimens prepared in this way, were tested for different properties viz., compressive strength (CS), split tensile strength (STS), flexural strength (FS), workability (W) and density (D). It was observed that incorporation of PET-Fs in the concrete reduces these properties of concrete however, concrete with coated PET-Fs were having better properties than the concrete with uncoated PET-Fs. Therefore, it could be implied that coating of PET-Fs may enhance the applicability of PET-Fs as a construction material.

Over the years, polymer-metal nanocomposites have been extensively investigated due to their potential ability to produce materials with novel mechanical, electronic, optical and magnetic properties for technological applications. In the current paper, we present the studies on cobalt (Co) nanoparticles embedded polyethylene terephthalate (PET) by ion beam sputtering technique. Co nanoparticle layer (10 nm thick) was deposited onto PET substrate by ion beam sputtering. Grazing incidence x-ray diffraction results reveal that the Co is present in the metallic form in the FCC phase. MOKE studies reveal the anisotropic behavior of PET/Co nanocomposite film. The results are discussed in the paper.

The research was conducted on growth and vital functions of watercress in the conditions of encapsulated mineral fertilizers treatment. The cyclic application of mineral fertilizers during three vegetation periods is simulated in this paper. Used mineral fertilizers are encapsulated on the basis of polyethylene terephthalate and polystyrene waste. It was found that the intermediate products of the polymer covering decomposition do not have a negative impact on the soil environment and the use of encapsulated fertilizers is safe for plants growing.

Blending of ZnO nanostructures (e.g. nanoparticles, nanorods, moonflowers etc.) in thermoplastic matrix enables the functional composite formations. The electric conductivity, thermal conductivity, photo-catalytic properties, magnetic properties, mechanical properties, morphological properties of thermoplastic materials are some of the quantities those can modify by the blending of ZnO nanostructures. The previous studies have been reported for the reinforcement of ZnO nanostructures in polyvinylidene difluoride (PVDF), acrylonitrile butadiene styrene (ABS), high density polyethylene (HDPE), low density polyethylene (LDPE), Polyethylene terephthalate (PET), polylactic acid (PLA) etc. for different application prospective such as preparations of the bio/biomedical sensors, charge storage devices, shape memory materials, magnetic structures etc. This study is a state of the art review for exploring the functionalities and application of the ZnO nanostructures reinforced thermoplastic materials.

Many researchers have utilized recycled plastic trash to substitute aggregate in concrete for decades, and this document describes the technical properties of recycled plastic waste in detail. The resin impacts the concrete's new qualities, which affects the concrete's mechanical properties and durability. The inclusion of resin modifies the mechanical characteristics and strength of the concrete, according to current test results. Plastic fibers derived from plastic trash bottles were used to reinforce ordinary concrete in this investigation. The compressive strength of cubes and cylinders made of standard and fiber-reinforced concrete is determined in the laboratory. The experiments used concrete grades M25 and M30 and two geometric fibers with a volume ratio of 0.0% to 3.0%, cured for 28 days. This document establishes the relationship between compressive strength and cylindrical strength for conventional reinforced concrete and plastic fibers and compares it with standards.

Plastics and their degradation products, microplastics (MPs), are ubiquitous in the environment, and urban and industrial soils may be the most polluted soils by this type of pollution. There is scarce information addressing human exposure to MPs from urban and industrial soils. This study assesses MP pollution in urban and industrial soils of two county capital cities in Iran, i.e. Abadan and Khorramshahr. The concentration of MPs ranged from 17 MPs/100 g industrial soil to 347 MPs/100 g urban soil, with a mean abundance of 122 MPs/100 g soil. Residential areas were the most contaminated by MPs among all the sampling sites. There, microfiber MPs, red and black, were the most abundant MPs, and it was also the case across sampling sites. Polyethylene terephthalate and polypropylene were the most common polymers among the investigated MPs, while nylon and polystyrene MPs were also present. Regarding MP sizes, those in the fraction 250–500 µm prevailed across all investigated sites. Estimated exposures to MPs through contact with the urban and industrial soils, for a normal scenario according to US EPA parameters, would lead to a daily intake < 1 MP for both adult and children, and their respective yearly intake of MPs is estimated in 6–127 and 12–253 MPs. Further research is needed to assess the health impact of current MP types and levels found in urban soil.

The development of highly-efficient photocatalyst for H2 production integrated with microplastic degradation is significant to meet the demand for clean energy and resolve “white pollution”. Herein, a series of MXene/ZnxCd1-xS photocatalysts were successfully fabricated for H2 evolution integrated with degradation of polyethylene terephthalate (PET). The resultant photocatalysts exhibited excellent photocatalytic performance, and the best photocatalytic H2 evolution rate can reach 14.17 mmol·g−1·h−1 in alkaline PET alkaline solution. What’s more, the PET was also converted to the useful organic micromolecule, including glycolate, acetate, ethanol, etc. The highly-efficient photocatalytic performance of MXene/ZnxCd1-xS photocatalysts can be attributed to the enhanced separation ability of photocarriers and optimum band structure with enhanced oxidation capacity of valence band. Finally, the photocatalytic mechanism was investigated in detail. Overall, this work supplied a new useful guidance for solving the energy problem and microplastic pollution issues, simultaneously.

Bio-derived polyethylene furanoate (PEF) has recently gained attention as a sustainable alternative to polyethylene terephthalate (PET), amidst environmental concerns over fossil fuel depletion. He...

A novel flexible capacitive pressure sensor based on hybrid micro-structured (HM) polydimethylsiloxane (PDMS) dielectric layer was developed. The HM-PDMS with M-tooth structured patterns was fabricated using a laser engraved acrylic master mold. The top and bottom electrodes were fabricated by depositing silver (Ag) on flexible polyethylene terephthalate (PET) substrate using additive screen-printing process. The pressure sensor was assembled by sandwiching two HM-PDMS based dielectric layers between the top and bottom electrodes. The capability of the developed pressure sensor to detect a wide range of pressure was investigated by applying varying pressure from 0 to 1 kPa, 1 to 10 kPa, and 10 kPa to 40 kPa. A sensitivity of 51.36% kPa-1, 8.37% kPa-1, and 2.46% kPa-1 was obtained for the pressure ranges of 0 to 1 kPa, 1 to 10 kPa, and 10 to 40 kPa, respectively. The capacitive pressure sensor response, hysteresis, and repeatability of the fabricated pressure sensor is investigated and presented in this paper. To demonstrate the wide sensing range of the pressure sensor, the sensor was attached to face mask for breath monitoring applications that require low pressure sensing of ~20 Pa, and to the hand glove for fingertip pressure monitoring applications that require relatively high pressure sensing of ~3 kPa.

A dual-band frequency selective surface (FSS) employing Ti3C2Tx deposited on a polyethylene terephthalate (PET) layer is proposed for Wi-Fi applications. The structure can afford dual-frequency pas...

Polymer matrix composite materials have found application in dentistry because of good mechanical properties, aesthetic, easy processing, and possibilities of the repair. Acrylates are materials used to make and repair dentures. Reinforcements in the form of short glass or polymer fibers are added to improve the mechanical properties of dental polymers. In this study, the processing of composite material with a polymer matrix from commercial auto-polymerized acrylate Simgal, with reinforcement in the form of short poly(ethylene terephthalate) (PET) fibers was examined. Samples were processed in three series: pure Simgal, Simgal/PET 1 wt% and Simgal/PET 3 wt%. The influence of the reinforcement in the form of short PET fibers on the mechanical properties of composite materials was investigated. Strength and hardness were tested by impact testing and Vickers microhardness, and it was shown that there is an increase in absorbed energy and hardness. The modulus was reduced by the addition of PET fibers and by increasing the amount of fibers in the composite. The increase in the amount of PET fibers also resulted in a smaller loss of surface mass of the samples compared to the pure matrix by 63% and 93%, respectively. Cavitation test revealed better cavitation resistance of composites than the pure acrylate.

There is a tremendous increase in plastic waste that negatively impacts the environment due to various industrial activities. Furthermore, plastic waste has non-biodegradable properties that make it hard to reduce its accumulation around the globe. Hence, this study aims to investigate the possibility of incorporating Polyethylene terephthalate (PET) waste as a partial replacement material of sand to improve the thermal insulation properties of cement sand brick by looking at findings of low thermal conductivity value. The study uses a PET plastic bottle that has been cut into small flakes and grind using a granulator machine to produce PET waste granules whose size is not more than 5 mm, similar to the sand size. This waste was added to other raw materials, i.e., cement and sand. The percentages of PET waste vary from 2.5%, 5%, and 7.5% by weight. This study produced two types of samples, i.e., control brick and PET waste cement sand brick. All samples undergo laboratory works involving geotechnical gradation, physical, mechanical, and thermal conductivity testing. Based on the results obtained, the optimum proportion of PET waste replacement in cement sand bricks making is 5% by its having the lowest thermal conductivity value of 0.581 W/mK and meeting the standard requirements of 3.90 MPa > 3.45 MPa (ASTM C129-11 for compressive strength), and 2,146 kg/m3 > 2,000 kg/m3 (ASTM C129-11 for normal weight non-loadbearing brick). Thus, PET plastic bottle waste can be a potential partial sand replacement material in cement sand bricks. Its potential to enhance the thermal conductivity of existing cement sand brick reduces sand consumption, solves plastic waste problems, and promotes a better environmentally-friendly construction industry.

A flame retardant unsaturated polyester resin (UPR) was prepared by methods of glycolysis of recycled polyethylene terephthalate (r-PET) via propylene glycol (PG) and diphenylsilanediol (DDS) as mixed glycolysis agent and esterification of the glycolyzed products with maleic anhydride (MA). The chemical structures of glycolyzed products and the resulted UPRs were characterized by fourier transform infrared (FTIR) and 1H nuclear magnetic resonance (1H-NMR). The peaks at the range of 540–465 cm−1 and 1643 cm−1 on the FTIR spectrum indicated the introduction of Si–O into the main chain of UPR/Si and the reaction between glycolyzed product and MA, respectively). The different amounts of aluminum hydroxide (ATH) was added in the resulted UPRs to obtain UPR composites. The effects of DDS ratio on the flame retardancy, thermal stability, mechanical properties of the resulted UPRs and their composites were investigated. The result showed that the flame retardancy of UPR composites was further improved by addition of ATH to the UPR composites. Finally, the synergistic flame retardant mechanism between DDS and ATH was discussed based on scanning electronic microscopy (SEM) morphologies and FTIR spectra of the residual char after horizontal burning tests (UL-94). It suggested that r-PET can be glycolyzed successfully with PG and DDS as mixed glycolysis agent and the flame retardancy of the resulted UPR based on the glycolyzed products and their composites were improved due to incorporation of DDS in the main chain of UPR and the addition of ATH.

Recycled polyethylene terephthalate (r-PET) is a widely recycled plastic employed for new textile production in the world. It reduces environmental impact and lowers cost of the production. For the traditional dyeing of polyethylene terephthalate (PET), commercial disperse dyes are generally used. In presented research the recycled r-PET fibres 6 den dyeing with disperse dyes Itosperse: Red, Blue and Yellow (concentration 3 Wt. %) were examined and the influence of the intensifier of a salicylic acid (with concentration of 4 - 10 g/L) in dye bath was investigated. The colour properties of dyed samples and colour fastness to washing were tested. It is concluded that the presence of the intensifier of salicylic acid improves dyeing results, but the optimal concentration differs for each dye. Colour fastness test to washing of the blue dyed samples showed the insignificant changes of colour parameters. In some cases the change of shade in presence of salicylic acid was observed.

The recycled low density polyethylene (LDPE), recycled high density polyethylene (HDPE) and recycled polyethylene terephthalate G copolyester (PETG) as post-processed plastic wastes from extrusion blow molding process were modified with blending process to improve the properties of those plastic wastes and decrease the amount of plastic wastes in the plastic processing plants. The recycled PETG was blended with recycled LDPE and recycled HDPE in various concentration from 0 wt% to 100 wt% in increments of 10 wt% as referred to LDPE/PETG blends and HDPE/PETG blends respectively prepared by co-twin screw extruder. The addition of PETG in the blending of LDPE and HDPE improved the mechanical properties and MFI of those polymer blends but decreased thermal stability, storage modulus, loss modulus and complex viscosity as compared to those of neat LDPE and neat HDPE. LDPE/PETG blends illustrated better impact properties and flexibility than those of HDPE/PETG blends.

Different types of polymer films were used in the combined in-mold decoration and microcellular injection molding (IMD/MIM) process. The multiphase fluid-solid coupled heat transfer model was established to study the thermal response at the melt filling stage in the IMD/MIM process. It was found that the temperature distributed asymmetrically along the thickness direction due to the changed heat transfer coefficient of the melt on the film side. When polyethylene terephthalate (PET) films were applied, the temperature of the melt-film interface increased faster and to be higher at the end of melt filling stage in comparison with the application of polycarbonate (PC) and thermoplastic polyurethane (TPU) films. And the effects of film types on the cellular structure, forming defects and mechanical properties of IMD/MIM parts were also studied experimentally. The results showed that the film types had no obvious effect on the cells size in the transition layer and the mechanical properties of the parts. Under certain film thickness, the offset distance of core layer was the largest with PET film used, while the offset distance was the smallest with TPU film used. And similar results were found for the warpage of the parts. However, an exactly opposite change occurred for the thickness of film-side transition layer and the bubble marks on the surface of the parts.

Accurately quantifying chemical additives with adverse health effects in plastic products is critical for environmental safety and risk assessment. In this work, a novel approach using solubility parameters (δ) as indicators for the extraction of additives in plastics was developed. The mechanism was evaluated by using 10 organic solvents with different solubility parameters to extract brominated flame-retardant-decabrominated diphenyl ether (BDE-209) in polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET). Certified reference materials (CRMs) or CRM candidate materials were applied as matrix materials. The extracted BDE-209 and solubility parameters of solvents could fit into a curve of a quadratic function. The value of abscissa corresponding to the vertex of the function was close to the solubility parameter of plastic calculated by the group contribution method (Δδ < 0.37). Toluene, n-hexane, and acetone were the solvents with high extraction efficiency for PE, PP, and PET, confirming the feasibility of the developed approach. The results of ethyl acetate and acetone indicated the high weight of functional groups affecting the dissolution behavior. The developed approach was further verified by analyzing penta-/octa-BDE and phthalate esters in PET and polyvinyl chloride (PVC) and finally applied to analyze 15 plastic products made of PP, PE, PET, polystyrene, and PVC. The detected tetrabromodiphenyl ether (BDE-47), BDE-209, decabromodiphenyl ethane, and di(2-ethylhexyl) terephthalate all matched the approach and verified its practicability for field sample analysis.

In this study, different types of polymers in postconsumer plastics with pure plastics have been studied. Highdensity polyethylene (HDPE1 and HDPE2), polyvinyl chloride (PVC3 and PVC4), polyethylene terephthalate (PET5 and PET6), and polypropylenes (PP7 and PP8) were compared using X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques. XRF has shown the spectral in K-lines of polymer materials present in plastics waste. The peak intensity and degree of crystallinity of commercial polymers are varied using XRD analysis. The intensity not attributable to the crystalline peaks may be regarded as the amorphous scattering and used as a template in analyzing the diffraction pattern of the samples. The XRD analysis helps to provide characteristic spectral lines whose intensities vary with the type of each constituent polymer. The combined usage of XRD and XRF techniques yielded very useful and effective results for a commercial plastic management.

Polyethylene terephthalate (PET) pre-prepared nano/micro fibers were treated by sodium hydroxide (NaOH) aqueous solution and then AgNPs were loaded on them through the soaking process. In total, eight samples were created. Then they were characterized by field emission scanning electron microscopy (FESEM), scanning electron microscopy (SEM), X-ray energy diffraction (EDS) spectroscopy and Fourier transform infrared (FTIR). Disk diffusion and colony counting tests were also performed. Samples containing AgNPs had growth inhibition zones with diameters between 19 and 26 mm while control samples had no inhibition zone. PET microfibers containing AgNPs had a larger inhibition zone on Staphylococcus aureus compared to other samples. The innovation of this research is the placement of AgNPs on the hydrophilic PET micro/nano fibers.

The main purpose of this paper is to develop a new manufacturing process leading to have antibacterial dyed non-absorbable braided polyethylene terephthalate (PET) sutures using biocompatible and non-toxic products. This manufacturing process allows better visibility of sutures in the surgical field and reduces the risk of infections and inflammatory reactions without affecting the mechanical properties while meeting the United States Pharmacopeia (USP) requirements. Plasma functionalization, acrylic acid (AA) grafting, and bioactive chitosan (CH) coating were used before the dyeing process with a biocompatible non-toxic acid dye, approved by the Food and Drug Administration (FDA). The influence of experimental parameters on the suture properties and the K/S values of the dyed sutures are investigated. Infrared spectroscopy confirms the presence of new bonds to immobilize chitosan on the surface of the suture. Mechanical tests confirm that the mechanical properties of sutures have not been affected. The in vitro antibacterial effect of dyed PET sutures showed an inhibition zone of 11 mm against S. aureus, 4 mm against P. aeruginosa, and 1 mm against E. coli. This study reveals that the new finishing process of sutures is a promising method to achieve an antibacterial effect with a uniform shade and smooth surfaces.

In order to improve the sustainable construction in Peru, throughout the recycling of non-biodegradable materials, a study of the influence of glass and Polyethylene terephthalate (PET) wastes in the physic properties of concrete bricks was carried out. They were made with a 1:5:2 cement, fine aggregate, and waste relation. Three proportions were studied named P-01, P-02, and P-03. Each proportion had a different content of glass and PET wastes, as a result, it was found that the average brick’s absorption was increased with PET wastes and it was reduced with glass wastes. On the other hand, the compressive strength value increased with glass wastes and it was reduced with PET wastes. Finally, it was found that P-02 was the most efficient concrete brick proportion to develop a sustainable construction, obeying the requirements of the Peruvian national building regulations.

In this paper, graphene oxide (GO) and maleic anhydride–functionalized pristine graphene (MAGN) based on Diels-Alder reaction were synthesized in order to comparatively study the reinforcement effect on the polyethylene terephthalate (PET) composites. PET nanocomposites with GO or MAGN were prepared by a melt-blending method with varying concentrations of nanofillers from 0.05 wt to 0.3 wt%. The structure, the thermal stability, and the mechanical and crystallization properties of the obtained PET composites were systematically investigated by scanning electronic microscopy (SEM), tensile tests, thermo-gravimetric analysis (TGA), differential scanning Calorimetry (DSC), and dynamic mechanical analysis (DMA). The results show that the thermal stability and the mechanical and crystallization properties of EPT are improved by GO and MAGN inclusion. When the filler loading was 0.1 wt%, the tensile strength of MAGN/PET and GO/PET was increased by 28.9 % and 11.8% compared with the pure PET, which indicates the MAGN shows a better reinforcement effect on PET nanocomposites. Moreover, the MAGN also acts as a more efficient nucleating agent for PET compared with GO exhibiting higher degrees of crystallinity.

In this study, we explore the structural, optical, and chemical properties of ZnO nanorods (NRs) grown through various transition metal (TM) dopings of Cu, Ni, Co, Ni-plus-Cu, and Ni-plus-Co, while investigating the effect of these external dopings on the performance of ZnO NR-based ultra-violet photodetectors (PDs) implemented on polyethylene terephthalate substrates. The TM dopings, especially Ni-plus-Cu or Ni-plus-Co co-doping, not only improve the crystalline quality but also significantly suppress the density of deep-level emission defects in as-grown ZnO NRs, as demonstrated by X-ray diffraction and photoluminescence. Furthermore, increased O/Zn stoichiometry from 0.55 (undoped) to 0.78 and 0.83 is achieved when the NRs doped with Ni-plus-Cu and Ni-plus-Co, respectively, as revealed by X-ray photoelectron spectroscopy. The highest current on–off ratio of ~51 and spectral responsivity of ~136 A/W are obtained from the PDs fabricated with the NRs doped with Ni-plus-Co. The response time of the PDs is also improved with TM dopings, and rise time and fall time are reduced to ~1/5 and ~1/4, respectively, in the case of Ni-plus-Co doping compared to the values of the device fabricated with undoped NRs.

The process of obtaining aerated (filled with air bubbles) polymer coatings has been developed and investigated by the method of flame spraying with an assessment of their ability to damp vibrations. A technology for the controlled formation of aerated polymer coatings has been developed while using the capabilities of the ОИМ (OIM) 050 polymer thermal atomizer design which consists in providing a concurrent air flow between the flame torch and the jet of powder material. The experiments have been carried out with such thermoplastic polymers as polyethylene terephthalate, high pressure polyethylene, ultra high molecular weight polyethylene, polyamide. It has been found that the aeration coefficient grows almost in direct proportion with an increase in the amount of air in the concurrent flow for all investigated polymer coatings. It is noted that the aeration process is influenced by the rheological properties of liquid polymers, or rather, the value of the polymer melt flow rate. The limiting values of air in the concurrent flow have been determined, which make it possible not to reduce the adhesion of polymer coatings to steel substrates by less than 6 MPa and not to decrease their hardness by more than 25–30 %. Studies of the damping properties of samples with polymer coatings have been carried out on a stand, the kinematic diagram of which is based on loading the free end of a cantilever sample, abrupt removal of the load and registration of free damped oscillations by an induction-type contactless sensor connected to a computer. It is shown that the use of aeration when forming noise-absorbing coatings on steel samples can increase their logarithmic damping decrement by 18–26 %.