scholarly journals 3D Printed Silicone Meniscus Implants: Influence of the 3D Printing Process on Properties of Silicone Implants

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2136
Author(s):  
Eric Luis ◽  
Houwen Matthew Pan ◽  
Anil Kumar Bastola ◽  
Ram Bajpai ◽  
Swee Leong Sing ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Weight Bearing ◽  
Thermo Gravimetric Analysis ◽  
Silicone Implants ◽  
Osteoarthritis Of The Knee ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Hydrogel Scaffolds ◽  
Custom Made ◽  
3D Printed

Osteoarthritis of the knee with meniscal pathologies is a severe meniscal pathology suffered by the aging population worldwide. However, conventional meniscal substitutes are not 3D-printable and lack the customizability of 3D printed implants and are not mechanically robust enough for human implantation. Similarly, 3D printed hydrogel scaffolds suffer from drawbacks of being mechanically weak and as a result patients are unable to execute immediate post-surgical weight-bearing ambulation and rehabilitation. To solve this problem, we have developed a 3D silicone meniscus implant which is (1) cytocompatible, (2) resistant to cyclic loading and mechanically similar to native meniscus, and (3) directly 3D printable. The main focus of this study is to determine whether the purity, composition, structure, dimensions and mechanical properties of silicone implants are affected by the use of a custom-made in-house 3D-printer. We have used the phosphate buffer saline (PBS) absorption test, Fourier transform infrared (FTIR) spectroscopy, surface profilometry, thermo-gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) to effectively assess and compare material properties between molded and 3D printed silicone samples.

Characterisation of Hydroxyapatite/Bacterial Cellulose Nanocomposites

2009 ◽  
Vol 17 (6) ◽  
pp. 353-358 ◽  
Author(s):  
Shengnan Zhang ◽  
Guangyao Xiong ◽  
Fang He ◽  
Yuan Huang ◽  
Yulin Wang ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Bacterial Cellulose ◽  
Photoelectron Spectroscopy ◽  
Thermo Gravimetric Analysis ◽  
Hydroxyl Groups ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Cellulose Nanocomposites

A novel nanocomposite material consisting of hydroxyapatite (HAp) deposited on a phosphorylated bacterial cellulose (BC) has been synthesised via a biomimetic route. X-ray photoelectron spectroscopy (XPS) showed that phosphate groups were successfully introduced to the hydroxyl groups of BC by phosphorylation reaction to promote the growth of calcium phosphate. Transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED) patterns of HAp/BC demonstrated that HAp crystals wrap the surfaces of BC fibres. In this work, HAp/BC nanocomposites were studied using thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The TGA result suggested that HAp/BC nanocomposite, similar to natural bone in terms of composition, contained carbonate ions, in agreement with our previous Fourier transform infrared (FTIR) spectroscopy results. Thermal behaviour differences between BC and HAp/BC were observed by differential scanning calorimetry (DSC). The thermal stability of HAp/BC obtained from DSC showed an improvement when compared to that of a pure BC sample.

scholarly journals Biocomposites of Bio-Polyethylene Reinforced with a Hydrothermal-Alkaline Sugarcane Bagasse Pulp and Coupled with a Bio-Based Compatibilizer

Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2158
Author(s):  
Nanci Vanesa Ehman ◽  
Diana Ita-Nagy ◽  
Fernando Esteban Felissia ◽  
María Evangelina Vallejos ◽  
Isabel Quispe ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
3D Printing ◽  
Water Absorption ◽  
Sugarcane Bagasse ◽  
Thermo Gravimetric Analysis ◽  
Decomposition Temperature ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Cradle To Gate ◽  
Bagasse Pulp

Bio-polyethylene (BioPE, derived from sugarcane), sugarcane bagasse pulp, and two compatibilizers (fossil and bio-based), were used to manufacture biocomposite filaments for 3D printing. Biocomposite filaments were manufactured and characterized in detail, including measurement of water absorption, mechanical properties, thermal stability and decomposition temperature (thermo-gravimetric analysis (TGA)). Differential scanning calorimetry (DSC) was performed to measure the glass transition temperature (Tg). Scanning electron microscopy (SEM) was applied to assess the fracture area of the filaments after mechanical testing. Increases of up to 10% in water absorption were measured for the samples with 40 wt% fibers and the fossil compatibilizer. The mechanical properties were improved by increasing the fraction of bagasse fibers from 0% to 20% and 40%. The suitability of the biocomposite filaments was tested for 3D printing, and some shapes were printed as demonstrators. Importantly, in a cradle-to-gate life cycle analysis of the biocomposites, we demonstrated that replacing fossil compatibilizer with a bio-based compatibilizer contributes to a reduction in CO2-eq emissions, and an increase in CO2 capture, achieving a CO2-eq storage of 2.12 kg CO2 eq/kg for the biocomposite containing 40% bagasse fibers and 6% bio-based compatibilizer.

Synthesis, characterization and corrosion protection properties of polyN-(p-bromophenyl)-2-methacrylamide-co-glycidyl methacrylate on low nickel stainless steel

2011 ◽  
Vol 31 (2-3) ◽  
Author(s):  
Sakvai Mohammed Safiullah ◽  
Deivasigamani Thirumoolan ◽  
Kottur Anver Basha ◽  
K. Mani Govindaraju ◽  
Dhanraj Gopi ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Corrosion Protection ◽  
Glycidyl Methacrylate ◽  
Electrochemical Impedance ◽  
Thermo Gravimetric Analysis ◽  
Gel Permeation Chromatography ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Protection Efficiency ◽  
Ft Ir

Abstract The synthesis of copolymers from different feed ratios of N-(p-bromophenyl)-2- methacrylamide (PBPMA) and glycidyl methacrylate (GMA) was achieved by using free radical solution polymerization technique and characterized using FT-IR, 1H and 13C NMR spectroscopy. The thermal stability of the synthesized copolymers was studied using thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The molecular weight of the copolymer is determined by gel permeation chromatography (GPC). The corrosion performances of low nickel stainless steel specimens dip coated with different composition of copolymers were investigated in 0.5 M H2SO4 using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) techniques. The polarization and impedance measurements showed different corrosion protection efficiency with change in composition of the copolymers. It was found that the corrosion protection properties are owing to the barrier effect of the polymer layer covered on the low nickel stainless steel surfaces. However, it is observed that the mole ratio of PBPMA and GMA plays a major role in the protective nature of the copolymer.

Graphene Nanoplates Filled Nylon 6,6 Nanocomposites, Morphological, Thermal, Mechanical and Solvent Uptake Study

2019 ◽  
Vol 41 (3) ◽  
pp. 388-388
Author(s):  
Khalid Saeed Khalid Saeed ◽  
Tariq Shah and Ahmad Hassan Tariq Shah and Ahmad Hassan
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Neutral Red ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Nucleation Effect ◽  
Morphological Studies ◽  
Solvent Uptake ◽  
Nylon 6,6 ◽  
Dsc Analyses ◽  
Graphene Nanoplates

Effect of graphene nanoplates (GNPs) on the properties of Nylon 6,6 (Nyl 6,6) is investigated in present study. The morphological studies presented that the GNPs were dispersed inside the Nyl 6,6 matrix. The thermo gravimetric analysis (TGA) illustrated that the thermal degradation of nanocomposites samples were started at the range of 350-393 oC, which was appreciably higher than neat Nyl 6,6 (360 oC). The differential scanning calorimetry (DSC) analyses revealed that the crystallization temperature (Tc) of GNPs/Nyl 6,6 increased as increased the addition of GNPs, which might be due to the nucleation effect of GNPs. The mechanical properties of Nyl 6,6 was enhanced by incorporation of GNPs upto the addition of an optimal quantity of filler (5%wt GNPs) into the polymer matrix. The stress yield and Young’s modulus of 5%wt GNPs/Nyl 6,6 was 96.79 and 1.54, N/nm2, respectively. Both Nyl 6,6 and nanocomposites samples were also used for the adsorption of Neutral red chloride (NRC) dye, which significantly remove the dye from the aqueous solution. The neat nylon 6,6 and GNPs (5 and 10 wt%)/Nyl 6,6 adsorbed about 88.49, 93.15, and 93.60% within 2 h, respectively.

Characterization of Novel Solid Dispersions of Moringa oleifera Leaf Powder Using Thermo-Analytical Techniques

Processes ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 2230
Author(s):  
Nontsikelelo Noxolo Tafu ◽  
Victoria A. Jideani
Keyword(s):  
Solid Dispersion ◽  
Moringa Oleifera ◽  
Solid Dispersions ◽  
Intermolecular Hydrogen Bond ◽  
Thermo Gravimetric Analysis ◽  
Analytical Techniques ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Hydrogen Bond Interactions ◽  
Leaf Powder

Moringa oleifera leaf powder (MOLP) has been identified as the most important functional ingredient owing to its rich nutritional profile and healthy effects. The solubility and functional properties of this ingredient can be enhanced through solid dispersion technology. This study aimed to investigate the effects of polyethylene glycols (PEGs) 4000 and 6000 as hydrophilic carriers and solid dispersion techniques (freeze-drying, melting, solvent evaporation, and microwave irradiation) on the crystallinity and thermal stability of solid-dispersed Moringa oleifera leaf powders (SDMOLPs). SDMOLPs were dully characterized using powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). The PXRD results revealed that the solid dispersions were partially amorphous with strong diffraction peaks at 2θ values of 19° and 23°. The calorimetric and thermogravimetric curves showed that PEGs conferred greater stability on the dispersions. The FTIR studyrevealed the existence of strong intermolecular hydrogen bond interactions between MOLP and PEG functional groups. MOLP solid dispersions may be useful in functional foods and beverages and nutraceutical formulations.

Decellularized liver-regenerative 3D printing biomaterials for cell-based liver therapies via a designed procedure combined with papain-containing reagent treatments and supercritical fluids

2021 ◽  
pp. 1-8
Author(s):  
Ching-Cheng Huang
Keyword(s):  
3D Printing ◽  
Thermo Gravimetric Analysis ◽  
Extraction Process ◽  
Gravimetric Analysis ◽  
Collagen Scaffolds ◽  
Scanning Calorimetry ◽  
Porcine Liver ◽  
Good Thermal Stability ◽  
Decellularized Liver ◽  
Liver Collagen

BACKGROUND: The biologic scaffolds derived from decellularized tissues and organs have been successfully developed in a variety of preclinical and/or clinical studies. OBJECTIVE: The new decellularized liver-regenerative 3D printing biomaterials were designed and prepared for cell-based liver therapies. METHODS: An extraction process was employed to remove the tissue and cellular molecules from porcine liver via pretreatment of supercritical fluid of carbon dioxide (ScCO2). Varying porosities of the decellularized liver tissues were created using papain-containing reagent treatments after ScCO2. RESULTS: The resulting liver-regenerative 3D printing biomaterials of decellularized liver collagen scaffolds were characterized by Fourier transform infrared spectroscopy, thermo-gravimetric analysis, differential scanning calorimetry and scanning electron microscopy. CONCLUSIONS: The decellularized liver collagen scaffolds with good thermal stability (>150 °C) were obtained and employed as liver-regenerative 3D printing biomaterials for cell-based liver therapies.

The Influence of Nickel Oxide Nanoparticle Dispersion on the Thermo Stability of Lubricant Oil

2019 ◽  
Vol 19 (01) ◽  
pp. 1850044
Author(s):  
K. Ramachandran ◽  
P. Navaneethakrishnan ◽  
M. Sivaraja
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Nanoparticle Dispersion ◽  
Nio Nanoparticles ◽  
Scanning Calorimetry ◽  
Lubricant Oil ◽  
Nickel Oxide Nanoparticle ◽  
Nanoparticles Dispersion ◽  
Thermo Stability

The homogeneous and substantial dispersion of nanoparticles into base fluids is vital since the final properties of any nanolubricant are estimated by their quality of stability. This paper addresses the effect of NiO nanoparticles dispersion into SN500 lubricant oil and its nonisothermal thermo stability. The dispersion of NiO nanoparticles is achieved by ultrasonication method. The thermo stability is estimated by Thermo Gravimetric Analysis (TGA), Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC). The result shows that the thermo stability of base fluid enhances up to 0.3[Formula: see text]wt.% particle concentration then it decreases due to agglomeration of dispersed nanoparticles. The findings recommend that 0.1[Formula: see text]wt.% and 0.3[Formula: see text]wt.% of NiO-nanolubricant can be used for the temperature-dependent applications up to 200∘C.

Optimization of Curing Conditions and Nanofiller Incorporation for Production of High Performance Laminated Kevlar/Epoxy Nanocomposites

2018 ◽  
Author(s):  
Abdel-Hamid I. Mourad ◽  
Mouza S. Al Mansoori ◽  
Lamia A. Al Marzooqi ◽  
Farah A. Genena ◽  
Nizamudeen Cherupurakal
Keyword(s):  
Oil And Gas ◽  
Mechanical Performance ◽  
Thermo Gravimetric Analysis ◽  
Applied Pressure ◽  
Curing Temperature ◽  
Gravimetric Analysis ◽  
Epoxy Nanocomposites ◽  
Scanning Calorimetry ◽  
Curing Conditions ◽  
Weight Percentage

Kevlar composite materials are getting scientific interest in repairing of oil and gas pipelines in both offshore and onshore due to their unique properties. Curing is one of the major factor in deciding the final mechanical performance of laminated Kevlar/epoxy nanocomposites. The parameters such as curing time, temperature and applied pressure during the hot pressing will affect chemistry of crosslinking of the epoxy matrix and interaction of epoxy with the Kevlar fiber. The present study is carried out to evaluate the optimal curing conditions of the Kevlar/epoxy nanocomposites. Three different nanofillers (namely Multi walled Carbon nanotubes (MWCNT), Silicon Carbide (SiC) and Aluminum Oxide (Al2O3)) are incorporated in different weight percentage. Differential Scanning Calorimetry (DSC) and Thermo-Gravimetric Analysis (TGA) tests are carried out to determine the thermal stability and optimal curing conditions. Mechanical performance is investigated by conducting flexure, and drop weight tests. The results show that, the optimal curing temperature for maximizing the mechanical properties is at 170°C. Peeling off the Kevlar layers are observed for nanocomposite samples cured under 100°C. Mechanical strength of the composites is enhanced by optimizing the curing conditions and nanofiller contents.

scholarly journals Preparation and structure of SiOCN fibres derived from cyclic silazane/poly-acrylic acid hybrid precursor

2019 ◽  
Vol 6 (10) ◽  
pp. 190690
Author(s):  
Zhongkan Ren ◽  
Christel Gervais ◽  
Gurpreet Singh
Keyword(s):  
Acrylic Acid ◽  
Photoelectron Spectroscopy ◽  
Thermo Gravimetric Analysis ◽  
Ceramic Matrix Composite ◽  
Linear Structure ◽  
Cost Effective ◽  
Gravimetric Analysis ◽  
Low Viscosity ◽  
Hybrid Precursor ◽  
Poly Acrylic Acid

Ceramic matrix composite (CMC) materials have been considered a desired solution for lightweight and high-temperature applications. Simultaneously, among all different CMC reinforcements, polymer-derived ceramic (PDC) fibres have gained attention for the intrinsic thermal stability and mechanical strength with simple and cost-effective synthesis techniques. Here, carbon-rich SiOCN fibres were synthesized via hand-drawing and polymer pyrolysis of a hybrid precursor of 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasilazane (TTCSZ) and poly-acrylic acid (PAA). The type of silazane reported in this work is considered as a major precursor for SiCN; however, it is unspinnable, due to its unfavourable physical properties (low viscosity) and chemical structure (cyclic rather than linear structure). The introduction of PAA to TTCSZ to create a hybrid precursor remarkably improved the spinnability of the silazane and should be widely applicable to other unspinnable PDC pre-ceramic polymers. Investigations on the structural and compositional development of the fibres were mainly conducted via Raman spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, nuclear magnetic resonance and thermo-gravimetric analysis to determine spinnability, free carbon content, cross-linking and pyrolysis behaviour of the fibres, respectively.

Synthesis and Characterization of the Bismaleimides Containing Aliphatic-ether Chain for Microelectronics Application

e-Polymers ◽  
2006 ◽  
Vol 6 (1) ◽  
Author(s):  
J. L. Feng ◽  
C. Y. Yue ◽  
K. S. Chian
Keyword(s):  
Chain Length ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Thermo Gravimetric ◽  
Degradation Temperature ◽  
Dielectric Thermal Analysis ◽  
Aliphatic Ether ◽  
Synthetic Reaction

AbstractThis project aims to develop and characterize a series of bismaleimide (BMI) polymers based on maleic anhydride and aliphatic-ether diamines. The effects of varying the chain length of aliphatic-ether diamines on the resultant bismaleimide systems were evaluated so that their suitability for microelectronics applications could be evaluated. The synthetic reaction and properties of the bismaleimide materials were investigated using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermo- Gravimetric Analysis (TGA), Dielectric Thermal Analysis (DEA) and rheometry. Results showed that thermal, dielectric and rheological properties were all affected by the main chain length of BMI. The magnitude of the dielectric constant at 100 kHz increases with the increasing chain length. The curing peak temperature, curing heat and degradation temperature of BMI, all decrease with the increasing chain length.

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