scholarly journals Effect of Polypyrrole on the Electrical, Dielectric and Mechanical Properties of Waterborne Epoxy Coatings

2020 ◽  
Vol 30 (1) ◽  
pp. 11
Author(s):  
Thu Thuy Thai ◽  
Thuy Duong Nguyen ◽  
Thi Thu Trang Nguyen ◽  
Gia Vu Pham ◽  
Dai Lam Tran ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Chemical Structure ◽  
Volume Resistivity ◽  
Chemical Oxidation ◽  
Epoxy System ◽  
Conducting Composite ◽  
Chemical Oxidation Polymerization ◽  
Waterborne Epoxy ◽  
The Matrix ◽  
Dielectric And Mechanical Properties

In this context, conducting composite based on waterborne epoxy system and polypyrrole (PPy) was investigated. The polypyrrole was synthesized by chemical oxidation polymerization. Its morphology and chemical structure were confirmed by using field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). Then, PPy was well-dispersed in the epoxy coating and had a good compatibility with the matrix. The effects of PPy on dielectric, electrical and mechanical properties of epoxy/PPy composites was examined. The dielectric constant and electrical conductivity of the coatings increased with addition of PPy fillers. Over to 15 wt. % of PPy loading, the volume resistivity of samples slightly decreased from 6.7 × 1010 to 1.5 × 1010 Ω cm. In contrast, the presence of PPy diminished both impact and abrasion resistance of the epoxy/PPy composites, down to 160 kg cm and 10.2 L/mil, respectively, but they stayed acceptable for the coatings. The results reveal that the epoxy containing polypyrrole is suitable for various electrical and dielectric applications.

SYNTHESIS AND ELECTRORHEOLOGY OF PHOSPHORIC ACID DOPED POLYANILINE SUSPENSIONS

2005 ◽  
Vol 19 (07n09) ◽  
pp. 1149-1155 ◽  
Author(s):  
C. H. HONG ◽  
H. J. CHOI
Keyword(s):  
Phosphoric Acid ◽  
Electric Fields ◽  
Chemical Structure ◽  
Chemical Oxidation ◽  
Chemical Oxidation Polymerization ◽  
Ft Ir ◽  
Fourier Transform Ir ◽  
Doped Polyaniline ◽  
Er Fluids ◽  
High Voltage Generator

Semiconducting phosphoric acid doped polyaniline ( PANI-H 3 PO 4) particles were synthesized by chemical oxidation polymerization, and their chemical structure and particle size were examined via Fourier transform IR spectroscopy (FT-IR) and scanning electron microscopy (SEM), respectively. Electrorheological (ER) fluids were prepared by dispersing the synthesized PANI-H 3 PO 4 particles in kerosine, and their steady shear rheological properties under applied electric fields were investigated using a rotational rheometer with a high-voltage generator. The PANI-H 3 PO 4 synthesized in this study possesses a typical ER behavior: large increase of shear stress with applied electric field strengths.

Effect of Dopants on Microstructure and Properties of Polyaniline and Polypyrrole

2011 ◽  
Vol 328-330 ◽  
pp. 1576-1579
Author(s):  
Lei Yang ◽  
Chang Sen Zhang
Keyword(s):  
Thermal Stability ◽  
Room Temperature ◽  
Volume Resistivity ◽  
Chemical Oxidation ◽  
Wide Range ◽  
Chemical Oxidation Polymerization ◽  
Resistivity Minimum ◽  
Conductive Properties ◽  
Thermal Stability Of ◽  
Better Than

Polyaniline (PANI) and polypyrrole (PPy) doping with hydrochloric acid (HCl), p-toluenesulfonate (pTSA) were successfully synthesized by chemical oxidation polymerization. Ammonium peroxydisulfate was used as an oxidizing agent at room temperature. Microstructure of PPy and PANI was studied by scanning electron microscopy (SEM). Discussed the acid concentration how influenced on the electrical conductivity properties of PANI and PPy, and also compared their resistivity and thermal stability. The results showed that HCl effectively improved conductive properties of PANI in a wide range concentrations, and pTSA in narrow range concentrations. When doping with HCl, the minimum volume resistivity of PANI was 0.24 Ω • cm, and PPy was about 10.5 Ω • cm. When doping with pTSA, the volume resistivity minimum of PANI was 1.3 Ω • cm, and PPy was 15.8 Ω • cm. The conductivity of PPy was weaker than PANI. The thermal stability of conducting polymers which doping with pTSA was better than which doping with HCl.

Synthesis of Water-soluble Polyaniline by Using Different Types of Cellulose Derivatives

2017 ◽  
Vol 25 (7) ◽  
pp. 515-520 ◽  
Author(s):  
Hazira Hussin ◽  
Seng Neon Gan ◽  
Sharifah Mohamad ◽  
Sook Wai Phang
Keyword(s):  
Chemical Structure ◽  
Hydroxypropyl Methylcellulose ◽  
Conductivity Measurement ◽  
Ammonium Persulfate ◽  
Chemical Oxidation ◽  
Water Soluble ◽  
Cellulose Derivatives ◽  
Electrical Conductivity Measurement ◽  
Chemical Oxidation Polymerization ◽  
Different Types

Pure polyaniline (PAni) is insoluble in water. Water-soluble complexes of PAni with different of cellulose derivatives were successfully synthesized by using chemical oxidation polymerization of aniline in aqueous solution of cellulose derivatives. In this study, cellulose derivatives such as methylcellulose (MC), hydroxypropyl cellulose (HPC), and hydroxypropyl methylcellulose (HPMC) had been used as a steric stabilizer, aniline (Ani) as a monomer with hydrogen chloride (HCl) as an acidic dopant, and ammonium persulfate (APS) as an initiator. The chemical structure of PAni complexes were confirmed by using Fourier Transform Infrared Spectroscopy (FTIR). The interactions of PAni and cellulose derivatives were observable through Ultraviolet-Visible Spectroscopy (UV-Vis) in the wavelength range of 300 nm to 900 nm. The Standard Four-Point Probe Method was used for the conductivity measurements. In the electrical conductivity measurement, PAni in toluene was used as a control. The result showed that water-soluble PAni-cellulose derivatives gave higher conductivity value (9.47 × 10−2 – 1.87 × 10−1 S/cm) than the pristine PAni (1.60 × 10−3 S/cm).

Morphology and Mechanical Properties of Polyethylene Terephthalate/Ethylene Propylene Diene Monomer (PET/EPDM) in the Presence of Nanoclay

2020 ◽  
Vol 57 (3) ◽  
pp. 249-259
Author(s):  
Baifen Liu ◽  
Mohammad Mirjalili ◽  
Peiman Valipour ◽  
Sajad Porzal ◽  
shirin Nourbakhsh
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Thermal Destruction ◽  
Processing Temperature ◽  
Tem Analysis ◽  
Maximum Stiffness ◽  
Cloisite 30B ◽  
Nano Clay ◽  
The Matrix ◽  
Sample Maximum

This research deals with the mechanical properties, microstructure, and interrelations of triple nanocomposite based on PET/EPDM/Nanoclay. These properties were examined in different percentages of PET/EPDM blend with compatibilizer (Styrene-Ethylene/Butylene-Styrene)-G-(Maleic anhydrate) (SEBS-g-MAH). Results showed that the addition of 15% SEBS-g-MAH improved the toughness and impact strength of this nanocomposite. SEM micrographs indicated the most stable fuzzy microstructure in a 50/50 mixture of scattered phases of EPDM/SEBS-g-MAH. The effects of percentages of 1, 3, 5, 7 nanoclay Cloisite 30B (C30B) on the improvement of the properties were evaluated. With the addition of nano clay, the toughness and impact strength was reduced. Thermal destruction of nanoclay in processing temperature led to the decreasing dispersion of clay plates in the matrix and a reduction in the distances of nano clay plates in the composite compared to pure nano clay. XRD and TEM analysis was used to demonstrate the results. By adding 1% of nanoclay to the optimal sample, maximum stiffness, and Impact strength, among other nanocomposites, was achieved.

scholarly journals Preparation of Long Sisal Fiber-Reinforced Polylactic Acid Biocomposites with Highly Improved Mechanical Performance

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1124
Author(s):  
Zhifang Liang ◽  
Hongwu Wu ◽  
Ruipu Liu ◽  
Caiquan Wu
Keyword(s):  
Mechanical Properties ◽  
Polylactic Acid ◽  
Mechanical Performance ◽  
Tensile Elongation ◽  
Sisal Fiber ◽  
Fiber Reinforced ◽  
Impact Performance ◽  
The Matrix ◽  
Blending Process ◽  
Extension Direction

Green biodegradable plastics have come into focus as an alternative to restricted plastic products. In this paper, continuous long sisal fiber (SF)/polylactic acid (PLA) premixes were prepared by an extrusion-rolling blending process, and then unidirectional continuous long sisal fiber-reinforced PLA composites (LSFCs) were prepared by compression molding to explore the effect of long fiber on the mechanical properties of sisal fiber-reinforced composites. As a comparison, random short sisal fiber-reinforced PLA composites (SSFCs) were prepared by open milling and molding. The experimental results show that continuous long sisal fiber/PLA premixes could be successfully obtained from this pre-blending process. It was found that the presence of long sisal fibers could greatly improve the tensile strength of LSFC material along the fiber extension direction and slightly increase its tensile elongation. Continuous long fibers in LSFCs could greatly participate in supporting the load applied to the composite material. However, when comparing the mechanical properties of the two composite materials, the poor compatibility between the fiber and the matrix made fiber’s reinforcement effect not well reflected in SSFCs. Similarly, the flexural performance and impact performance of LSFCs had been improved considerably versus SSFCs.

scholarly journals Effects of Various Types of Expandable Graphite and Blackcurrant Pomace on the Properties of Viscoelastic Polyurethane Foams

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1801
Author(s):  
Rafał Oliwa ◽  
Joanna Ryszkowska ◽  
Mariusz Oleksy ◽  
Monika Auguścik-Królikowska ◽  
Małgorzata Gzik ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Chemical Structure ◽  
Oxygen Index ◽  
Polyurethane Foams ◽  
Expandable Graphite ◽  
Ftir Analysis ◽  
Limiting Oxygen Index ◽  
Peak Heat Release Rate ◽  
Physical And Chemical ◽  
Scanning Electron

We investigated the effect of the type and amount of expandable graphite (EG) and blackcurrant pomace (BCP) on the flammability, thermal stability, mechanical properties, physical, and chemical structure of viscoelastic polyurethane foams (VEF). For this purpose, the polyurethane foams containing EG, BCP, and EG with BCP were obtained. The content of EG varied in the range of 3–15 per hundred polyols (php), while the BCP content was 30 php. Based on the obtained results, it was found that the additional introduction of BCPs into EG-containing composites allows for an additive effect in improving the functional properties of viscoelastic polyurethane foams. As a result, the composite containing 30 php of BCP and 15 php of EG with the largest particle size and expanded volume shows the largest change in the studied parameters (hardness (H) = 2.65 kPa (+16.2%), limiting oxygen index (LOI) = 26% (+44.4%), and peak heat release rate (pHRR) = 15.5 kW/m2 (−87.4%)). In addition, this composite was characterized by the highest char yield (m600 = 17.9% (+44.1%)). In turn, the change in mechanical properties is related to a change in the physical and chemical structure of the foams as indicated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis.

Sign in / Sign up

Export Citation Format

Share Document