scholarly journals Cylindrical Polyurethane Scaffold Fabricated Using the Phase Inversion Method: Influence of Process Parameters on Scaffolds’ Morphology and Mechanical Properties

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2977
Author(s):  
Aleksandra Kuźmińska ◽  
Dominika Kwarta ◽  
Tomasz Ciach ◽  
Beata A. Butruk-Raszeja
Keyword(s):  
Mechanical Properties ◽  
Polyvinyl Alcohol ◽  
Polymer Solution ◽  
Process Parameters ◽  
Phase Inversion ◽  
Young Modulus ◽  
Process Time ◽  
Inversion Method ◽  
Influence Of Process Parameters ◽  
Phase Inversion Technique

This work presents a method of obtaining cylindrical polymer structures with a given diameter (approx. 5 mm) using the phase inversion technique. As part of the work, the influence of process parameters (polymer hardness, polymer solution concentration, the composition of the non-solvent solution, process time) on the scaffolds’ morphology was investigated. Additionally, the influence of the addition of porogen on the scaffold’s mechanical properties was analyzed. It has been shown that the use of a 20% polymer solution of medium hardness (ChronoFlex C45D) and carrying out the process for 24 h in 0:100 water/ethanol leads to the achievement of repeatable structures with adequate flexibility. Among the three types of porogens tested (NaCl, hexane, polyvinyl alcohol), the most favorable results were obtained for 10% polyvinyl alcohol (PVA). The addition of PVA increases the range of pore diameters and the value of the mean pore diameter (9.6 ± 3.2 vs. 15.2 ± 6.4) while reducing the elasticity of the structure (Young modulus = 3.6 ± 1.5 MPa vs. 9.7 ± 4.3 MPa).

scholarly journals Control of Nanostructured Polysulfone Membrane Preparation by Phase Inversion Method

Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2349
Author(s):  
Cristina Bărdacă Urducea ◽  
Aurelia Cristina Nechifor ◽  
Ioana Alina Dimulescu ◽  
Ovidiu Oprea ◽  
Gheorghe Nechifor ◽  
...  
Keyword(s):  
Polymer Solution ◽  
Phase Inversion ◽  
Membrane Preparation ◽  
Electrochemical Technique ◽  
Coagulation Bath ◽  
Inversion Method ◽  
Polysulfone Membrane ◽  
Water Permeation ◽  
Phase Inversion Technique ◽  
Phase Inversion Method

The preparation of membranes from polymer solutions by the phase inversion method, the immersion—precipitation technique has proved since the beginning of obtaining technological membranes the most versatile and simple possibility to create polymeric membrane nanostructures. Classically, the phase inversion technique involves four essential steps: Preparation of a polymer solution in the desired solvent, the formation of the polymer solution film on a flat support, the immersion of the film in a coagulation bath containing polymer solvents, and membrane conditioning. All phase inversion stages are important for the prepared membrane’s nanostructure and have been studied in detail for more than six decades. In this paper, we explored, through an electrochemical technique, the influence of the contact time with the polymer film’s environment until the introduction into the coagulation bath. The system chosen for membrane preparation is polysulfone-dimethylformamide-aqueous ethanol solution (PSf-DMF-EW). The obtained nanostructured membranes were characterized morphologically and structurally by scanning electron microscopy (SEM) and thermal analysis (TA), and in terms of process performance through water permeation and bovine serum albumin retention (BSA). The membrane characteristics were correlated with the polymeric film exposure time to the environment until the contact with the coagulation bath, following the diagram of the electrochemical parameters provided by the electrochemical technique.

scholarly journals The impact of molded pulp product process on the mechanical properties of molded Bleached Chemi-Thermo-Mechanical Pulp

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Claire Dislaire ◽  
Yves Grohens ◽  
Bastien Seantier ◽  
Marion Muzy
Keyword(s):  
Mechanical Properties ◽  
Water Uptake ◽  
Process Parameters ◽  
Manufacturing Process ◽  
Water Immersion ◽  
Young Modulus ◽  
Drying Time ◽  
Mechanical Pulp ◽  
Hygroscopic Properties ◽  
The Impact

AbstractThis study was carried out using bleached softwood Chemi-Thermo-Mechanical Pulp to evaluate the influence of Molded Pulp Products’ manufacturing process parameters on the finished products’ mechanical and hygroscopic properties. A Taguchi table was done to make 8 tests with specific process parameters such as moulds temperature, pulping time, drying time, and pressing time. The results of these tests were used to obtain an optimized manufacturing process with improved mechanical properties and a lower water uptake after sorption analysis and water immersion. The optimized process parameters allowed us to improve the Young’ Modulus after 30h immersion of 58% and a water uptake reduction of 78% with the first 8 tests done.

Fabrication and characterization of friction stir processed Al 6061 reinforced with TiB2-Al2O3

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ch. Mohana Rao ◽  
K. Mallikarjuna Rao
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Process Parameters ◽  
Friction Stir Processing ◽  
Practical Implication ◽  
Research Work ◽  
Influence Of Process Parameters ◽  
Volume Percentage ◽  
Content Type ◽  
Friction Stir

PurposeThe objective of the paper is to evaluate the fabrication process and to study the influence of process parameters of friction stir processing of 6061-TiB2-Al2O3 Aluminum alloy surface composite on microhardness tensile strength, and microstructure.Design/methodology/approachFriction stir processing method is used for attaining the desired mechanical properties, and selectively processed reinforcements to fabricate the samples. The Taguchi technique was used to optimize rotational speed, travel speed and volume percentage of reinforcement particles to enhance the mechanical properties of 6061-TiB2-Al2O3 Aluminum alloy composite.FindingsThe fabrication of surface composites through FSP allows new inventions in terms of material with enhanced surface layers without changing the base metal.Practical implicationsTo examine the behavior of the surface of the composites in the different zones, the practical implication consists of the use of different characterization techniques like optical microscopy and scanning microscopy for microstructural behavior and the measurement of hardness and tensile tests for mechanical behavior.Originality/valueThe research work consists of tool design and process parameters, which can affect the final product (microstructural changes), and the performance of the modified surface layer behavior was studied and presented.

scholarly journals Study on Optimization of Wet Milling Process for the Development of Albendazole Containing Nanosuspension with Improved Dissolution

2020 ◽  
Vol 64 (4) ◽  
pp. 401-420
Author(s):  
Viktor Fülöp ◽  
Géza Jakab ◽  
Bence Tóth ◽  
Emese Balogh ◽  
István Antal
Keyword(s):  
Process Parameters ◽  
Dissolution Kinetics ◽  
Polymorphic Transition ◽  
Milling Process ◽  
Process Time ◽  
Wet Milling ◽  
Influence Of Process Parameters ◽  
Freundlich Equation ◽  
Milling Medium ◽  
Kinetics Of

The main objective of this work was to show the potential of the optimization of top-down wet planetary bead milling process parameters (milling speed, process time and size of the milling medium) by Design Of Experiments (DOE) approach for the development of albendazole (ABZ) containing nanosuspension with improved dissolution. In addition, the influence of process parameters (capacity of milling container, applied volume of milling beads, size of the milling medium, milling speed, milling time) on ABZ polymorphic transition has also been investigated. The optimized, milled formula yielded ~ 145.39 times reduction in mean particle size (182.200 ± 1.3130 nm) compared to unmilled dispersion, which demonstrated 13.50 times gain in mean dissolution rate value compared to the unmilled dispersion in medium at pH = 1.2. No lag time values were observed in the dissolution kinetics of the nanosuspension in comparison with the unmilled samples. Moreover, maximal mean solubility value was also improved by 1.45 times compared to the unmilled suspension, in medium at pH = 6.8, supporting the significance of the Ostwald-Freundlich equation. Diffraction pattern comparisons have indicated a polymorphic transition of albendazole to Form II, which was more pronounced in smaller container at high milling speed values and prolonged operations.

Preparation of high-oriented molybdenum thin films using DC reactive magnetronsputtering

2017 ◽  
Vol 31 (07) ◽  
pp. 1750059 ◽  
Author(s):  
Zhengguo Shang ◽  
Dongling Li ◽  
She Yin ◽  
Shengqiang Wang
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Surface Roughness ◽  
Process Parameters ◽  
Gas Flow ◽  
Lattice Mismatch ◽  
Practical Significance ◽  
Process Time ◽  
Process Conditions ◽  
Influence Of Process Parameters

Since molybdenum (Mo) thin film has been used widely recently, it attracts plenty of attention, like it is a good candidate of back contact material for CuIn[Formula: see text]Ga[Formula: see text]Se[Formula: see text]S[Formula: see text] (CIGSeS) solar cells development; thanks to its more conductive and higher adhesive property. Besides, molybdenum thin film is an ideal material for aluminum nitride (AlN) thin film preparation and attributes to the tiny (−1.0%) lattice mismatch between Mo and AlN. As we know that the quality of Mo thin film is mainly dependent on process conditions, it brings a practical significance to study the influence of process parameters on Mo thin film properties. In this work, various sputtering conditions are employed to explore the feasibility of depositing a layer of molybdenum film with good quality by DC reactive magnetron sputtering. The influence of process parameters such as power, gas flow, substrate temperature and process time on the crystallinity and crystal orientation of Mo thin films is investigated. X-ray diffraction (XRD) measurements and atomic force microscope (AFM) are used to characterize the properties and surface roughness, respectively. According to comparative analysis on the results, process parameters are optimized. The full width at half maximum (FWHM) of the rocking curves of the (110) Mo is decreased to 2.7[Formula: see text], and the (110) Mo peaks reached [Formula: see text] counts. The grain size and the surface roughness have been measured as 20 Å and 3.8 nm, respectively, at 200[Formula: see text]C.

Sign in / Sign up

Export Citation Format

Share Document