bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morphology of Microinjection Molded iPP Parts in Controlled Conditions
Authors: Salomone Rita , Liparoti Sara , Speranza Vito , Pantani Roberto 
Published: October 2022

AbstractA part made of just one material (mono‐material) is a new frontier in reducing environmental impact of plastic, being 100% recyclable. The focus of this work is on the possibility of controlling the properties of parts obtained by microinjection molding (μIM). μIM tests in variothermal conditions are conducted on an isotactic polypropylene. Two variothermal steps are adopted: the filling and packing stages are conducted at one selected mold temperature, and subsequent annealing steps are conducted while the sample is still inside the mold. A comparison with the parts produced under constant mold temperature is also performed. Electronic microscopy is adopted for the characterization of morphology. Furthermore, atomic force microscopy coupled with HarmoniX (HMX) tool allows detecting simultaneously local morphology and mechanical properties. The part morphology is characterized by a fibrillar layer close to the sample walls and a spherulitic core; a transition zone is also detectable in between. Morphology significantly influences mechanical properties: the transition zone shows the minimum value of elastic modulus, additionally, the elastic modulus increases with spherulite dimensions. Eventually, the annealing step results to be crucial in determining the part properties and can be adopted as a robust method to tailor properties through the process.
Accelerated Aging Test Modeling for Polycarbonate: Effects of Light Source
Authors: Ishida Takato , Kitagaki Ryoma 
Published: October 2022

AbstractThis work addresses to propose a model to reproduce accelerated aging results for polycarbonate. Four accelerated aging conditions are studied, including several light sources. In this study, aging behaviors are monitored by the yellowing index. Obtained simulations are well‐tracked the aging data for four accelerated aging conditions. Besides, the features of accelerating environments by a phase plane plot are challenged to visualize.
Molecular‐Dynamics Modeling of Nafion Membranes
Authors: Sengupta Soumyadipta , Pant Rakesh , Venkatnathan Arun , Lyulin Alexey V. 
Published: October 2022

AbstractThe Nafion is a commonly used polyelectrolyte membrane (PEM) in fuel cells and flow batteries. Nanocomposites of Nafion are used to enhance temperature resistance and proton conductivity. The molecular‐dynamics simulation results are reported for Nafion films of different thicknesses confined between two potential walls of variable wettability, mimicking the nanofiller surfaces. The water cluster sizes show an increase with film thickness for the high wettability cases, in agreement with SAXS experiments. The in‐plane water diffusion is considerably enhanced for the high wettability walls. The first results on the annealing effects on both structure, dynamics, and electric conductivity of the membranes are also reported. The hydrophilic channels evolution upon annealing will be discussed.
Embrittlement of Poly(butylene terephthalate) Induced by Injection Molding Process
Authors: Loyer Camille , Régnier Gilles , Duval Vincent , Richaud Emmanuel 
Published: October 2022

AbstractPoly(butylene terephthalate) (PBT) dumb‐bell samples are injection molded. Tensile tests reveal a brittle behavior for samples manufactured at high temperature (280°C) and long residence times contrarily to those processed at 240°C and 260°C with moderate residence times. Average weight molar mass and DSC measurements are exploited to derive an embrittlement criterion. The comparison with some literature data suggests that samples are mainly degraded by a thermolysis process with minor effect of oxygen.
Thermal Degradation of Fluorosilicone Elastomers
Authors: Richaud Emmanuel , Pires Leticia , Roland Sébastien , Truffault Laurianne , Laiarinandrasana Lucien , Corfa Alice , Pinaud Julien , Caillol Sylvain , Ladmiral Vincent , Beauvais Christophe 
Published: October 2022

AbstractThis paper explores the structure‐relationships involved in the degradation of fluorosilicones (FVMQs). For that purpose, FVMQs are thermally aged at 280 °C under various atmospheres (nitrogen, atmospheric air, pure oxygen). It seems that FVMQs undergo a strong mass loss irrespectively of the atmosphere. Under nitrogen, a chain scission (unzipping) mechanism is suspected whereas under air, a crosslinking mechanisms leads to an increase in tensile modulus. A degradation mechanism is proposed as a basis for lifetime prediction.
Redesign of a Metallic Component Using Polylactic Acid – PLA by Fused Deposition Modeling – FDM for Durability Increase
Authors: Jiga Gabriel , Crunţeanu Daniel‐Eugeniu , Dobrescu Tiberiu Gabriel , Brăileanu Patricia Isabela , Pascu Nicoleta Elisabeta 
Published: October 2022

AbstractThe term “3D printing” can refer to a variety of processes where material is deposited, joined, or solidified under computer control to create a three‐dimensional (3D) object. According to this principle, the material is added (such as fluid molecules or powder grains being fused together), typically layer by layer. One of the key advantages of 3D printing is the ability to produce very complex shapes or geometries, from the simplest to the most complex, that will be otherwise impossible to construct by hand, including hollow parts or parts with internal truss structures to reduce weight. In industries and companies where 3D printing is still a relatively new addition, the polylactic acid (PLA) material is the best option, because it is known in the industry as the easiest filament material to print. It is ideal for those who are looking to carry out fast prototyping, therefore it is the perfect choice for quick work. In this article, the authors intend to establish a set of printing rules for a geometric shape made of polymeric material (PLA) through the 3D printing process for a practical application and to present as much as possible the behavior in time of this printed component that replaces a non‐corrosive metal component.
Degradation of PVDF‐HFP Matrix
Authors: Julienne Fanon , Richaud Emmanuel 
Published: October 2022

AbstractThis paper explores both physical ageing of polyvinylidene fluoride (PVDF) and its copolymers with hexafluoropropylene (HFP). Water ageing and annealing are shown to have a negligible influence on mechanical properties. Chemical ageing is thus expected to be the main source of long‐term degradation. The nature of associated chemical trackers is discussed but it seems clear that their fraction is very slow for low temperature thermal ageing.
Macromolecular Mobility Changes Induced by Thermal Aging of Epoxy‐amine Polymer Networks
Authors: Delannoy Romain , Richaud Emmanuel , Tognetti Vincent , Quélennec Blandine , Delbreilh Laurent , Delpouve Nicolas 
Published: October 2022

AbstractChanges in macromolecular mobility during the thermal oxidation of epoxy‐amine thermoset networks are addressed in this study. Three epoxy‐amine systems, cured with DGEBA and three similar aliphatic hardeners – ethylenediamine (EDA), diethylenetriamine (DETA), and triethylenetetramine (TETA) – aged at 160°C are characterized by dynamic mechanical analysis (DMA). Results show a split of the single initial α relaxation peak with aging, which may imply that chain scissions are preferred at certain oxidizable sites in the network. A β relaxation can be identified around ‐60°C and does not seem to evolve much with aging, while another sub‐glass transition around 30°C decreases with it. Implications of this work both with mechanical fracture properties and with segmental mobility of radical chemical functions involved in bimolecular oxidation reactions have yet to be confirmed.
Physical Aging of an Epoxy Resin for Civil Engineering Applications from Fast Scanning Calorimetry Investigations
Authors: Quelennec Blandine , Delpouve Nicolas , Delbreilh Laurent , Delannoy Romain , Richaud Emmanuel 
Published: October 2022

AbstractThis works deals with the structural relaxation of an epoxy resin based on bisphenol A diglycidyl ether polymer (DGEBA) and 4,7,10‐Trioxa‐1, 13‐tridecanediamine (TTDA) hardener. The physical aging experiments are performed in situ using fast scanning calorimetry (FSC). The profile of the relaxation enthalpy with temperature is obtained close to the glass transition by annealing the resin during 10 min at various aging temperatures. From this profile, the structural relaxation is probed at various distances from the glass transition temperature, with aging times ranging from 0 to 1000 min. The Tool–Narayanaswamy–Moynihan (TNM) model is employed to analyze the relaxation data.
Migration of Electroconductive Carbon Nanoparticles in Polymer Composites Melts
Authors: Lebedev Oleg V. , Goncharuk Galina P. , Yablokov Mikhail Yu. , Kurkin Tikhon S. , Piskarev Mikhail S. , Golubev Evgeny K. , Ozerin Alexander N. 
Published: October 2022

AbstractProcess of nanoscale carbon filler migration in polymer composite melts is studied. Monotonous decrease of electrical resistance is observed for composite materials during their stay in a melted state. This is especially pronounced for composites with concentration of filler much lower than percolation threshold determined for a specific matrix/filler/mixing method combination. This phenomenon can be observed for composites based on different polymer matrices. Also, it is demonstrated that the type and geometry of the electrically conductive filler does not affect presence of the phenomena. A setup for measurement of conductance for volume and surface layer components is used. The results of electrical conductance measurements of the polymer composite melt using this setup allows to attribute the increase of composite material conductance to formation of filler enriched surface layer. To obtain information on the processes occurring at the microscopic level, molecular dynamics simulations are conducted. Variation of several simulation parameters with comparison of the results to experimental data allows to understand the macroscopic composite material conductance behavior.
Effect of Cooling Air in the Film Blowing Process on the Properties of PLA/PBAT Films
Authors: Pietrosanto Arianna , Scarfato Paola , Maio Luciano Di , Incarnato Loredana 
Published: October 2022

AbstractPoly(lactide) (PLA) and poly(butylene‐adipate‐co‐terephthalate) (PBAT) blends are among the most promising biodegradable materials for flexible packaging applications and the film blowing is one of the most common techniques to make plastic films. In this work, a study on the effect of the cooling air during the production process of blown films made by compatibilized PLA/PBAT blend has been performed. The application of cooling air has led to a significant reduction of the thermal shrinkage of the films in the transverse direction, respect to the machine direction, and has been beneficial in order to improve their mechanical and optical properties.
Polymer Insulator Processing‐Organic Transistor Performance Relationship Investigated through Admittance Spectroscopy
Authors: Liguori Rosalba , Licciardo Gian Domenico , Benedetto Luigi Di 
Published: October 2022

AbstractAdmittance spectroscopy is employed to explain the property differences observe between organic thin film transistors (OTFTs) fabricated with various gate insulator layers based on poly(4‐vinylphenol) (PVP) and poly(methyl methacrylate) (PMMA). The objective is achieved through the development of an equivalent circuit and a compact analytical model of the device core structure, namely, the metal–insulator–semiconductor (MIS) capacitor. The model fitting with experimental data allows to extract a wide range of parameters and, in particular, demonstrates the critical role played by the interface between insulator and semiconductor layers.
Active Coated Films to Decrease Browning of Minimally Processed Banana Fruit
Authors: Apicella Annalisa , Carlucci Elisa , Leneveu‐Jenvrin Charlène , Remize Fabienne , Scarfato Paola 
Published: October 2022

AbstractMinimally processed fruit presents a short shelf‐life because of cellular endogenous metabolism or microbial development. Fruit browning mostly results from phenolic compound oxidation. Banana (Musa acuminata Cavendish) cuts are particularly prone to enzymatic browning, resulting in unattractive color and modifications of aroma. In this study, the effect of two different eco‐sustainable packaging films on minimally processed banana is investigated. The films differ by the substrate, either polyethylene terephthalate (PET) or a fully biodegradable mix of polylactic acid (PLA) and polybuthylene adipate terephtalate (PBAT). They are coated with an amorphous PLA layer containing as antioxidant an active agent deriving from olive processing wastes. Minimally processed banana slices are prepared, packed, and stored at 4°C. Microbiological quality, color, pH, firmness, and polyphenol oxidase activity are evaluated during storage. The PET films show a better efficacy to limit browning, mainly due to the higher oxygen barrier properties compare to the PLA/PBAT. Best results are obtained with PET films with 5% of active phase.
Investigation of an Upcycling Strategy for Mixed Plastic Wastes from Urban Collection
Authors: Ferraioli Raffaella , Incarnato Loredana , Maio Luciano Di , Scarfato Paola 
Published: October 2022

AbstractIn this work, an upcycling strategy, aimed to upgrade the performances of recyclates deriving from sorting and mechanical recycling of mixed plastic waste recovered from the urban collection (UPW), is explored. To this aim, UPW samples are firstly analyzed to get information on their polymer constituents (type and relative amount), and then they are upcycled with the addition of different amounts of a polymer compatibilizer, a CaCO3‐based moisture absorber, and/or odor removers. All used additives give interesting benefits on processability and quality of the recycled UPW. In particular, the stiffness is increased up to ca. 22%, with the addition of 5 wt% of compatibilizer, and up to ca. 36%, with the addition of 5 wt% of moisture absorber, which also give better processability thanks to its moisture removal action. The odor absorber significantly reduces the smell of the recyclates, as found in preliminary odor recognition test sensory evaluation.
Floating Microdisks Rotated by Molecular Motors
Authors: Nyrkova Irina A. , Semenov Alexander N. 
Published: October 2022

AbstractA possibility of utilization of molecular motors for creation of unidirectional rotation of tiny disks floating on a surface is considered theoretically. The bottom side of the disk is covered with grafted motors combined with flat blades submerges into a viscous liquid for torque generation. When exposes to UV‐light, the motors start to rotate all in the same direction, and they transfer their rotation to the blades creating a mechanical torque that turns the disk. The disk angular velocity scales as ω ∼ Ω L/R where Ω is motor angular velocity, L is the length of the oars, R is the micro‐disk size. A competition between directional ballistic‐type rotation and rotative diffusion is considered. The setup can be used for evaluation of the primary motor parameters: the motor rotation speed Ω = 2πf, and the maximum motor torque load Mmax.
Electrothermal Actuation and Release of Adhesiveness of Conductive Carbon Nanotube/Epoxy Composites by Joule Heating
Authors: Slobodian Petr , Riha Pavel , Olejnik Robert , Matyas Jiri 
Published: October 2022

AbstractThe effect of an embedded electro‐conductive multi‐walled carbon nanotube (MWCNT) nanopaper in an epoxy matrix on the release of the frozen actuation force and the actuation torque in the carbon nanotube nanopaper/epoxy composite after heating above its glass transition temperature is assessed. The presence of the nanopaper augments the recovery of the actuation stress by the factor of two in comparison with the pure epoxy strip. The strengthening of the composite is attributed to the interlocking of the carbon nanotubes with the epoxy. Moreover, the internally heated electro‐conductive carbon nanotube nanopaper/epoxy composite not only substantially shortens curing time while retaining comparable strength of the adhesive bonding of the steel surfaces but also enables a release of such bonds by repeated application of DC current.
Rheology for Modeling of Extrusion of Wood Plastic Composites
Authors: Wilczyński Krzysztof , Buziak Kamila , Nastaj Andrzej , Lewandowski Adrian , Wilczynski Krzysztof J. 
Published: October 2022

AbstractExtensive rheological studies on the wood plastic composites (WPC) of various wood flour content based on the polypropylene (PP) matrix are presented. Viscous flow properties as well as the slip and yield stress phenomena are discussed. Rheological models of Klein and Ostwald de Waele are used for flow modeling, Navier model is applied for slip description and Bingham model is used for yield stress. Process simulations are performed, using recently developed the global computer model of WPC extrusion, to predict the process parameters (flow rate, pressure, and temperature development, melting rate, etc.), and to study the influence of the WPC material characteristics on the process flow. Simulations are validated experimentally, and are discussed with respect to both rheological and modeling aspects. It is concluded that the location of the extrusion operating point which defines the thermo‐mechanical process conditions is fundamentally dependent on the rheological material characteristics, including yield stress and wall slipping.
Algorithms for Flaw Detection by SHM with Static Sensors Approach
Authors: Iannone Michele 
Published: October 2022

AbstractStructural Health Monitoring (SHM) is a technology aimed to monitor the soundness of the structures. Applications for aircraft structure are largely investigated. The goal is to utilize the information acquired during the monitoring to save maintenance costs, improve flight safety, and design lighter structures. There are different issues investigated by SHM research, like load monitoring and impact detection. The most primarily investigated issue is damage detection, that is, developing a system that utilizes sensors to detect the damages in the structure. The damage detection can be performed with two different types of sensors: dynamic and static sensors. Dynamic sensors work by the transmission of waves through the structures. Defects are identified by deviation and reflection of the waves by damages. The SHM approach described in this work uses static sensors, like strain gages or fiber optics. The strain fields under load in pristine and damaged conditions are compared; damages are identified by evaluating the change in the strain field. Developed and patented in Leonardo Aircraft, two different algorithms for damage detection are described in this work. The algorithms are based on reverse finite element model (F.E.M.) and neural networks.
Optimization of Pyro‐gasification of Carbon Fiber Reinforced Polymers (CFRPs)
Authors: Montorsi Francesco , Brancolini Gianluca , Mazzocchetti Laura , Benelli Tiziana , Giorgini Loris 
Published: October 2022

AbstractThis work focuses on the optimization of pyro‐gasification process of carbon fiber reinforced polymers (CFRPs) with the aim of recovering carbon fibers (CFs) with properties suitable for the production of new more sustainable composites with high performances. In particular, the pyro‐gasification process is carried out on cured CFRPs panels based on both epoxy (EC) and vinyl ester (VC) matrices, which are the two most used resins for CFRPs. The matrix degradation is evaluated via sample's weight loss measurement and the recovered CFs obtained after different time of treatment are analyzed to identify convenient pyro‐gasification conditions to avoid damaging of the recovered CFs. The obtained results highlight the importance of the thickness of the composites to be treated for the identification of the more suitable pyro‐gasification conditions.
A MATLAB‐Based Software for Estimating Measurement Uncertainties in Capillary Viscometry
Authors: Malagutti Lorenzo , Mazzanti Valentina , Mollica Francesco 
Published: October 2022

AbstractThe Mooney wall slip correction procedure is sometimes mandatory in the rheological characterization via capillary viscometry of certain complex fluids that have the tendency of slipping at solid walls. Besides making the measurement more complex, the Mooney procedure may give rise to measurement error amplification due to an imprecise knowledge of the capillary radius, even if the uncertainty is of the order of 0.01 mm. This error amplification may be so large that the result becomes grossly inaccurate, and in the worst case the procedure may even not produce a physically acceptable result. In this work a MATLAB‐based software that can help researchers determine the maximum allowable inaccuracy on the capillary diameter that can yield feasible data for fluids characterization is devised. For best results, though, the user should know in advance the constitutive characteristics of the unknown fluid in an approximate sense.
Advances in analytical microfluidic workflows for differential cancer diagnosis
Authors: Hasanzadeh Kafshgari Morteza , Hayden Oliver 
Published: October 2022

AbstractEarly detection and functional analysis of circulating tumor cells (CTCs) in liquid biopsy rather than counting them offer great promise as physicians can improve differential diagnosis for second‐ or third‐line treatment beyond today's genotype information from next‐generation sequencing and the limited statistical power of histopathology analysis. Microfluidics holds a great potential for an accurate and reliable isolation and analytical examination of cancer liquid biopsy. This review describes fundamentals and technological breakthroughs of immunolabeled and label‐free analytical microfluidic chips (µ‐chips), developed to screen and examine CTCs. The impacts of highly‐selective biomarkers and their features on the assembly and renovation of high‐tech immunolabeled and label‐free µ‐chips are discussed. Owing to significant impacts of multifunctional nanostructures on the performance of analytical µ‐chips based on engineering‐driven workflows, this review also focuses on their critical roles for screening CTCs benefited from the nanoscale physicochemical features. The advantages of integrated analytical µ‐chips are then identified and examined regarding their dominated sorting technologies. Furthermore, this review explores innovative technologies incorporating downstream cellular‐/molecular analysis into integrative analytical µ‐chips to pave the way for non‐invasive point‐of‐care diagnostics.