Macromolecular Symposia

Maou, Khaoula; Belloufi, Abderrahim; Abdelkrim, Mourad; Maior, Ioana; Opran, Constantin Gheorghe

doi: 10.1002/masy.202200192pmid: N/A

This work presents the preparation process of composite from date palm fibers and Phenolic as a matrix by compression molding. The composites are prepared with a different weight fraction of fiber from 40 to 60 wt%. The enhancement of the mechanical properties is related to the good interaction and adhesion between the filler and the matrix which is estimated by analyzing the mechanical properties of the produced composite using diverse mathematical models as Hirsch, Pukanszky, and Schrager. The results reveal that the fiber loading has a great influence on the improvement of Young's modulus and tensile strength of the Phenolic compared to the neat Phenolic. The results also show that the Hirsch model is valid for the evaluation of the elastic modulus of treated date palm fibers (TDPFs) Phenolic (PH) composites with R2 = 0.97. Regarding the evaluation of the tensile strength of Phenolic composites, it appears clear that the Pukanszky and Schrager models are adaptable for the UDPFs/PH composites. However, the Pukanszky model is not suitable for the TDPFs/PH composites.

Vasile, Alexandru; Coropeţchi, Iulian Constantin; Constantinescu, Dan Mihai; Sorohan, Ştefan.; Picu, Catalin Radu

doi: 10.1002/masy.202200191pmid: N/A

The simulated annealing (SA) method is used in this work as to optimize the in‐plane stiffness of composite materials. Various configurations of the composite differ by the spatial distribution of hard voxels. The microstructure is assumed to be periodic, with a given length of periodicity in voxels in each of the two directions. The solution is obtained using the PyAnsys software under an MIT License, which is a collection of Python packages that enable the usage of ANSYS products. The SA algorithms prove to be very efficient, as they result in obtaining the one of the first three maximum values for the stiffness objective function for at least 98 out of 100 random trials. Therefore, SA can be successfully used for the microstructural design of composites at a fraction of the computational cost required by the brute force approach.

Hrițuc, Adelina; Mihalache, Andrei Marius; Slătineanu, Laurențiu; Dodun, Oana; Nagîț, Gheorghe

doi: 10.1002/masy.202200187pmid: N/A

Among the interesting thermal properties of polymeric materials is questionable their ability to transfer heat. The last decades have shown a significant expansion of manufacturing parts from polymeric materials using 3D printing processes. It is known that these processes allow changing the values of some input factors in the 3D printing workflow, which also leads to a change in the way the polymer material is arranged in part and, therefore, to a change in the capacity of the polymer material to transmit heat. To better understand how the variation of some input factors in the 3D printing process can change the way heat is transferred in test samples of polylactic acid (PLA) manufactured by 3D printing, a relatively simple device is designed whereby one of the surfaces of the test sample comes into contact with an aluminum alloy part heated using electrical resistance. Recording images using an infrared video camera helped to complete the information on how heat is transmitted through the test sample.

Bora, Manisha; Chabukswar, Vasant; Lamanna, Giuseppe

doi: 10.1002/masy.202200152pmid: N/A

In the present study, polyaniline (PANI) and ferrous oxide (α‐Fe2O3) are amalgamated for ammonia sensing purpose. The hybrid nanocomposite is prepared by a single step in situ chemical oxidative polymerization of aniline in presence of hydrothermally prepared α‐Fe2O3 nanoparticles. The structural and compositional analyses of the hybrid material are fully executed by FTIR, PXRD, and SEM techniques. A naive, exceedingly selective, quickly restorable, and ambient temperature functioning ammonia detecting device is established by using PANI/α‐Fe2O3. The investigation results indicate that the PANI/α‐Fe2O3 hybrid nanocomposite exhibits selective sensing ability towards ammonia vapors. The PANI/α‐Fe2O3 displays excellent response for 5 ppm and maximum response for 100 ppm of ammonia. The response time of the PANI/α‐Fe2O3 sensor is found to be quick with reasonably short recovery time. Due to excellent reusability, good environmental stability, and highly economical synthesis the PANI/α‐Fe2O3 delivers a capable, simple, and efficient sensor system for ammonia detection at ambient temperature.

Năstase, Marian‐Sebastian; Costea, Mihai; Jiga, Gabriel; Alexandru, Tudor George

doi: 10.1002/masy.202200178pmid: N/A

This paper deals with the analysis and comparative studies of the two of the most used types of polymer filaments dedicated to the 3D printing industry. The study is focused on the mechanical, elastic, and thermal properties of two different types of plastic materials filaments – acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) as well as on future development in various categories like industrial, medical, home decoration, and education. For carrying out this study, different specimens are printed using fused filament fabrication (FFF) technique, taking into account an infill percentage of 30% with a triangular shape as pattern type (internal structure).

Raffaini, Giuseppina; Ganazzoli, Fabio

doi: 10.1002/masy.202200144pmid: N/A

Protein adsorption on biomaterial surfaces is a crucial step for biocompatibility. Albumin is the most abundant blood protein, and then this protein is important for biomaterials that will come into contact with blood. In previous work a theoretical study based on molecular mechanics (MM) and molecular dynamics (MD) methods is carried out at atomistic level to investigate the adsorption process of albumin A‐subdomain on graphite surface and single‐walled carbon nanotubes (SWCNTs) having different curvature. The aim of this work is to study the adsorption process of the albumin A‐subdomain on four (10,10) SWCNTs in a crystalline arrangement in order to understand how the curvature of ordered nanotubes affects the adsorption process, providing also a simplified model of a rough surface at the nanometer level of a small crystalline domain. Interestingly, this soft albumin fragment having three α‐helices in the native state, yields a short β‐sheets arrangement during the MD run. This finding suggests the importance not only of the rigidity of protein but also the curvature of the surface which can induce a secondary structure other than the native one. This theoretical work can be useful for investigating aspects that influence the conformation, then both the functionality of proteins adsorbed on CNT surfaces and their biocompatibility, and the favorable interactions interesting for NT solubilization to prepare reinforced composite materials.

Moritzer, Elmar; Hecker, Felix

doi: 10.1002/masy.202200181pmid: N/A

Currently, the fused deposition modeling (FDM) process is the most common additive manufacturing technology. The principle of the FDM process is the strand wise deposition of molten thermoplastic polymers, by feeding a filament trough a heated nozzle. Due to the strand and layer wise deposition the cooling of the manufactured component is not uniform. This leads to dimensional deviations which may cause the component to be unusable for the desired application. In this paper, a method is described which is based on the shrinkage compensation through the adaption of every single raster line in components manufactured with the FDM process. The shrinkage compensation is based on a model resulting from a DOE which considers the main influencing factors on the shrinkage behavior of raster lines in the FDM process. An in‐house developed software analyzes the component and locally applies the shrinkage compensation with consideration of the boundary conditions, e.g., the position of the raster line in the component and the process parameters. Following, a validation using a simple geometry is conducted to show the effect of the presented adaptive scaling method.

Hamour, Noura; Boukerrou, Amar; Beaugrand, Johnny

doi: 10.1002/masy.202200195pmid: N/A

The present work is dedicated to the study of the mechanical and rheological properties of poly (hydroxybutyrate‐co‐hydroxyvalerate) PHBV blends with polypropylene PP. Given the incompatibility of these homopolymers, the use of a compatibilizing agent is essential. For this purpose, titanium dioxide (TiO2) and maleic anhydride (MA) are used. These constituents are chosen on the basis of some work that showed a high compatibility between it and the two homopolymers PHBV and PP. Thus, this copolymer has a great potential to improve the interfacial adhesion between these two polymers. From the results obtained from the techniques used in this study, it can be concluded that the immiscible PP/PHBV mixture can be effectively compatibilizing for by maleic anhydride. The latter is able to create chemical bonds between the macromolecular chains of the two polymers at the interface and therefore improves their properties.

Lamanna, Giuseppe; Opran, Constantin G.

doi: 10.1002/masy.202370029pmid: N/A

Tunsoiu, Nicolae; Doicin, Cristian‐Vasile; Ulmeanu, Mihaela‐Elena; Dugăeșescu, Ileana; Tunsoiu, Maria‐Cristina

doi: 10.1002/masy.202200176pmid: N/A

A complex smart product is usually made up of three main systems, namely the mechanical, electronic, and software systems. The current paper proposes a targeted design structure for the electronic system of a bespoke training equipment, so that it enables customized training strategies for ball sports. This is achieved through innovative technical solutions which enable customizable ball trajectories through programmed rotational angles of the launching system. In this case, the electronic system provides focused solutions to determine and project the specific ball trajectories, while ensuring a high degree of repeatability. Selecting the appropriate electronic components, which facilitate and enhance the capabilities of hardware components, is key in order to create a bespoke and modular training equipment concept. In order to actuate and control custom 3D printed components, an adaptable electronic system is designed. In this case, the electronic system commands the actuation of the motors and controls the acquisition of data from various sensors for the proper functioning of the product prototype. For the design and manufacturing of the bespoke sports training equipment, principal and secondary motors are used, which actuate several components: a custom 3D printed launch blade; a microcontroller; a gyroscope for position management and control; a sensor for sending commands from a remote control; an Arduino board for communication between motors and the software application; switching sources; motor drivers.