scholarly journals Comparative Studies on Polyurethane Composites Filled with Polyaniline and Graphene for DLP-Type 3D Printing

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 67 ◽  
Author(s):  
Hyeonseo Joo ◽  
Sunghun Cho
Keyword(s):  
3D Printing ◽  
Comparative Studies ◽  
Solution Process ◽  
Sem Images ◽  
Digital Light Processing ◽  
Wide Range ◽  
Light Curing ◽  
Ft Ir ◽  
Polyurethane Composites ◽  
Ft Ir Spectroscopy

Digital light processing (DLP)-type 3D printing ensures several advantages, such as an easy solution process, a short printing time, high-quality printing, and selective light curing. Furthermore, polyurethane (PU) is among the promising candidates for 3D printing because of its wide range of applications. This work reports comparative studies on the fabrication and optimization of PU composites using a polyaniline (PANI) nanomaterial and a graphene sheet (GS) for DLP-type 3D printing. The morphologies and dispersion of the printed PU composites were studied by field emission scanning electron microscope (FE-SEM) images. Bonding structures in the PU composites were investigated by Fourier-transform infrared (FT-IR) spectroscopy. As-prepared PU/PANI and PU/GS composites with different filler contents were successfully printed into sculptures with different sizes and shapes. The PU/PANI and PU/GS composites exhibit the improved sheet resistance, which is up to 8.57 × 104 times (1.19 × 106 ohm/sq) lower and 1.27 × 105 times (8.05 × 105 ohm/sq) lower, respectively, than the pristine PU (1.02 × 1011 ohm/sq). Moreover, the PU/PANI and PU/GS composites demonstrate 1.41 times (44.5 MPa) higher and 2.19 times (69.3 MPa) higher tensile strengths compared with the pristine PU (31.6 MPa). This work suggests the potential uses of highly conductive PU composites for DLP-type 3D printing.

scholarly journals Multidimensional Ln-Aminophthalate Photoluminescent Coordination Polymers

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1786
Author(s):  
Carla Queirós ◽  
Chen Sun ◽  
Ana M. G. Silva ◽  
Baltazar de Castro ◽  
Juan Cabanillas-Gonzalez ◽  
...  
Keyword(s):  
Water Content ◽  
Coordination Polymers ◽  
Metal Ion ◽  
Low Cost ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wide Range ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.

scholarly journals Rapid Fabrication by Digital Light Processing 3D Printing of a SlipChip with Movable Ports for Local Delivery to Ex Vivo Organ Cultures

Micromachines ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 993
Author(s):  
Megan A Catterton ◽  
Alexander G Ball ◽  
Rebecca R Pompano
Keyword(s):  
3D Printing ◽  
Ex Vivo ◽  
Local Delivery ◽  
Tissue Slices ◽  
Digital Light Processing ◽  
Rapid Fabrication ◽  
Wide Range ◽  
Scale Levels ◽  
Range Of Functions

SlipChips are two-part microfluidic devices that can be reconfigured to change fluidic pathways for a wide range of functions, including tissue stimulation. Currently, fabrication of these devices at the prototype stage requires a skilled microfluidic technician, e.g., for wet etching or alignment steps. In most cases, SlipChip functionality requires an optically clear, smooth, and flat surface that is fluorophilic and hydrophobic. Here, we tested digital light processing (DLP) 3D printing, which is rapid, reproducible, and easily shared, as a solution for fabrication of SlipChips at the prototype stage. As a case study, we sought to fabricate a SlipChip intended for local delivery to live tissue slices through a movable microfluidic port. The device was comprised of two multi-layer components: an enclosed channel with a delivery port and a culture chamber for tissue slices with a permeable support. Once the design was optimized, we demonstrated its function by locally delivering a chemical probe to slices of hydrogel and to living tissue with up to 120 µm spatial resolution. By establishing the design principles for 3D printing of SlipChip devices, this work will enhance the ability to rapidly prototype such devices at mid-scale levels of production.

Effect of surface modification on the compressive properties of silica fume/polyurethane composites

2016 ◽  
Vol 36 (8) ◽  
pp. 847-852 ◽  
Author(s):  
Di Shao ◽  
Jianzhi Diao ◽  
Lijie Wang ◽  
Long Li
Keyword(s):  
Electron Microscopy ◽  
Silica Fume ◽  
Test Machine ◽  
Modified Silica ◽  
Transmission Electron ◽  
Unmodified Silica ◽  
Ft Ir ◽  
Polyurethane Composites ◽  
Effect Of Surface ◽  
Ft Ir Spectroscopy

Abstract Silica fume was modified by a silane coupling agent (KH-550). The modified silica fume was further investigated to reinforce polyurethane (PU) composites. Unmodified and modified silica fume reinforced PU composites were prepared. Through the comparisons of Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) of unmodified and modified silica fume, the agglomerations of silica fume particles were effectively prevented as KH-550 was grafted. The compressive strength of the modified silica fume/PU composites was largely improved, because KH-550 could react with both silica fume and PU. Meanwhile, modified silica fume turned from hydrophilic to hydrophobic; a better dispersion was realized in the PU elastomers compared to the unmodified silica fume. The reinforcement effects were evaluated based on the results of a universal test machine in comparison with unmodified silica fume/PU composites.

scholarly journals Evaluation of structural, optical and physical properties of polyurethane composites doped with metal alkoxides

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Marzieh Nadafan ◽  
Javid Zamir Anvari
Keyword(s):  
Physical Properties ◽  
Ir Spectra ◽  
Window Size ◽  
Microscopy Imaging ◽  
One Step ◽  
Ft Ir ◽  
Polyurethane Composites ◽  
Bonding Characteristics ◽  
Polymerization Method ◽  
Ft Ir Spectroscopy

AbstractIn this research, polyurethane (PU)/tetraethyl orthosilicate (TEOS) composite was prepared via one-step polymerization method using different concentrations of TEOS in PU. The structural, optical and physical properties of PU composite were characterized by SEM imaging, FT-IR spectroscopy, water uptake, Raman spectroscopy and optical microscopy imaging of synthesized samples. The SEM results showed that by adding TEOS to the PU, the cell and window size of synthesized samples decreased. This result was also observed in the optical micrographs. The bonding characteristics of PU/TEOS composites were analyzed using Raman and FT-IR spectra. According to the FT-IR spectra, the degree of phase separation (DPS) and hydrogen bonding index, R, in 800 μl TEOS/PU had the highest R and DPS factors. By adding different concentrations of TEOS to PU, the apparent density decreased but the real density increased. The total, open and closed porosity of the synthesized samples were calculated. At low loading of TEOS in PU, the open porosity of the samples increased. The PU/TEOS composites may be promising candidates for absorbing sound.

scholarly journals Characterization of Waste Organic Matter by FT-IR Spectroscopy: Application in Waste Science

2002 ◽  
Vol 56 (9) ◽  
pp. 1170-1175 ◽  
Author(s):  
E. Smidt ◽  
P. Lechner ◽  
M. Schwanninger ◽  
G. Haberhauer ◽  
M. H. Gerzabek
Keyword(s):  
Organic Matter ◽  
Spectroscopic Properties ◽  
Wide Range ◽  
Methylene Groups ◽  
Ft Ir ◽  
Series Of Experiments ◽  
Fingerprint Region ◽  
Inorganic Components ◽  
Ft Ir Spectroscopy

A series of experiments has shown that FT-IR (Fourier transform infrared) spectroscopy is a helpful tool for characterizing waste organic matter, its decomposition, and stabilization in rotting processes. A specific set of differently treated input materials, originating from various composting plants, was chosen to reflect a wide range of spectroscopic properties. The approach to FT-IR spectra interpretation is presented. Changes of relative absorbances of the band at 2925 cm−1 (methylene groups of aliphatics) reflect the progress and dynamics of composting processes. Different processes can be compared by the specific development of their 2925 cm−1 band. Nitrate was quantified by calibrating nitrate band heights with added amounts of KNO3. The concentrations and band heights (absorbances) were linearly correlated ( R2 = 0.9968, SD = 0.001). Bands of inorganic components are useful to assess the decomposition process because they also indicate the development of organic matter. Different wastes can be distinguished by their fingerprint region (1500–900 cm−1). This region also reveals fresh and undecomposed materials. The presence or absence of specific bands provides information about the decomposition status of materials.

scholarly journals CO2 Separation with Polymer/Aniline Composite Membranes

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1363
Author(s):  
Hwa Jin Lee ◽  
Sang Wook Kang
Keyword(s):  
Benzene Ring ◽  
Polymer Matrix ◽  
Composite Membranes ◽  
Separation Performance ◽  
Amino Group ◽  
Sem Images ◽  
Ft Ir ◽  
High Separation ◽  
Ft Ir Spectroscopy

Polymer composite membranes containing aniline were prepared for CO2/N2 separation. Aniline was selected for high separation performance as an additive containing both the benzene ring to interfere with gas transport and an amino group that could induce the accelerated transport of CO2 molecules. As a result, when aniline having both a benzene ring and an amino group was incorporated into polymer membranes, the selectivity was largely enhanced by the role of both gas barriers and CO2 carriers. Selective layers coated on the polysulfone were identified by scanning electron microscopy (SEM) images and the interaction with aniline in the polymer matrix was confirmed by FT-IR spectroscopy. The binding energy of oxygen in the polymer matrix was investigated by XPS, and the thermal stability of the composite membrane was confirmed by TGA.

scholarly journals Effects of Treatment Temperature on Properties of Starch-based Adhesives

BioResources ◽  
2015 ◽  
Vol 10 (2) ◽  
pp. 3520-3530 ◽  
Author(s):  
Hongwei Yu ◽  
Yuan Cao ◽  
Qun Fang ◽  
Zhikun Liu
Keyword(s):  
Polyvinyl Alcohol ◽  
Bond Strength ◽  
Corn Starch ◽  
Treatment Temperature ◽  
Hydroxyl Groups ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Ft Ir ◽  
Acidic Conditions ◽  
Ft Ir Spectroscopy

Starch-based adhesives were developed by hydrolyzing starch with polyvinyl alcohol under alkaline and acidic conditions at various treatment temperatures. The chemical and physical structures of the corn starch and hydrolyzed starch were characterized with Fourier Transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and scanning electronic microscopy (SEM). Thermal degradation and bond strength were also evaluated. The results indicated that the bond strength of starch adhesives reached a maximum value at 40 °C. The FI-IR results showed that the amount of hydroxyl groups first increased and then decreased with increasing treatment temperature. When the treatment temperature was 55 °C the crystallinity of treated starch was the lowest and the thermal resistance also the weakest; it decreased by 10.1% and 13.6% respectively compared to untreated starch. Obvious erosion could be observed from the SEM images of treated starch. In addition, the interaction of polyvinyl alcohol (PVA) and starch also could be observed, and the results indicated that the compatibility between starch and PVA became better and better as the treated temperature was increased.

scholarly journals Preparation and Characterization of PVA-Cellulose Micro Crystal Composite Film from Jute fiber

2021 ◽  
Author(s):  
Md. Zahid Hasan ◽  
Yeasin Arafat ◽  
M. Mahbubul Bashar ◽  
Md. Nabi Newaz Niloy ◽  
Md Imranul Islam ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Composite Films ◽  
Particle Diameter ◽  
Jute Fiber ◽  
Average Particle ◽  
Sem Images ◽  
Oh Groups ◽  
Ft Ir ◽  
Higher Temperature ◽  
Ft Ir Spectroscopy

Abstract Herein, the microcrystalline cellulose (MCC) was obtained from jut fiber by ammonium persulfate (APS) oxidation process and thus polyvinyl alcohol (PVA) composite films were prepared by the reinforcement of MCC in a solution casting method. The surface chemistry, thermal properties and surface morphology of MCC and PVA-MCC composite films were studied by FT-IR spectroscopy, thermogravimetric analyzer and scanning electron microscopy. The SEM images confirmed the rod like MCC with average particle diameter 4.6 µm and length in 48.4 µm. The FT-IR spectroscopy revealed the complete removal of lignin and hemicellulose from jute fiber. A peak at 1730 cm− 1 was introduced in MCC due to oxidation with APS. The absorption peak of –OH groups in PVA-MCC composite films were shifted, somewhat disappeared and weakened due to the intra and inter molecular hydrogen bonding of MCC and OH groups in PVA. Thermogravimetric analysis expressed the thermal behavior of MCC and PVA-MCC composite films. Initially the thermal stability of PVA-MCC composite films was lower than the pristine MCC but at higher temperature (> 300℃) it showed better stability indicating the applicability of the composite at higher temperature.

scholarly journals A novel method for extraction, quantification, and identification of microplastics in CreamType of cosmetic products

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Soohyun Lee ◽  
Tai Gyu Lee
Keyword(s):  
Nile Red ◽  
Cosmetic Products ◽  
Digestion Method ◽  
Accurate Analysis ◽  
Sem Images ◽  
Cosmetic Ingredients ◽  
Before And After ◽  
Ft Ir ◽  
Novel Method ◽  
Ft Ir Spectroscopy

AbstractThe objective of this study was to develop an accessible and accurate analysis method for microplastics that have been unintentionally added to cream cosmetic products. An experiment was performed on three cleansing creams in rich and viscous formulations. A spiked sample was prepared by adding polyethylene (PE) microspheres to the cleansing creams. After removing cosmetic ingredients from the creams using chemical digestion, damage to the PE microspheres was identified using Fourier transform infrared (FT-IR) spectroscopy. Field emission scanning electron microscopy (FE-SEM) images were obtained before and after digestion and used to characterize the morphology of the PE microspheres. The highest digestion efficiency was obtained using a chemical digestion method consisting of heating and stirring a sample in a 10 wt% KOH solution at 55 °C and 300 rpm for 5 days and did not damage the PE microspheres. The Nile red (9-diethylamino-5H-benzo[α]phenoxazine-5-one) staining method was effective in identifying small microplastics (< 106 μm). The optimal staining conditions are 5 μg/ml Nile red in n-hexane for green wavelengths.

scholarly journals Fabrication of Conducting Polyacrylate Resin Solution with Polyaniline Nanofiber and Graphene for Conductive 3D Printing Application

Polymers ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1003 ◽  
Author(s):  
Hoseong Han ◽  
Sunghun Cho
Keyword(s):  
3D Printing ◽  
Three Dimensional ◽  
Optical Microscope ◽  
Graphene Sheets ◽  
Digital Light Processing ◽  
Three Dimensional Printing ◽  
Resin Solution ◽  
Light Curing ◽  
Dimensional Printing ◽  
Printing Time

Three-dimensional printing based on the digital light processing (DLP) method offers solution processability, fast printing time, and high-quality printing through selective light curing of photopolymers. This research relates to a method of dispersing polyaniline nanofibers (PANI NFs) and graphene sheets in a polyacrylate resin solution for optimizing the conductive solution suitable for DLP-type 3D printing. Dispersion and morphology of the samples with different filler contents were investigated by field emission scanning electron microscope (FE-SEM) and optical microscope (OM) analyses. The polyacrylate composite solution employing the PANI NFs and graphene was printed well with various shapes and sizes through the 3D printing of DLP technology. In addition, the electrical properties of the printed sculptures have been investigated using a 4-point probe measurement system. The printed sculpture containing the PANI NFs and graphene sheets exhibited electrical conductivity (4.00 × 10−9 S/cm) up to 107 times higher than the pure polyacrylate (1.1 × 10−16 S/cm). This work suggests potential application of the PANI NF/graphene cofiller system for DLP-type 3D printing.

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