Researchers from the Faculty of Engineering of Universiti Teknologi MARA (UiTM), Malaysia, have studied the capability of new polymers derived from potato starch as insulators which do not show any remarkable electro activity.
The majority of all polymers are insulators which do not show any remarkable electro activity. In the past, researchers have found out how to obtain a conducting polymer by the introduction of salts, plasticizer and nanofillers.
Uniform dispersion of plasticizer and fillers in salt-polymer matrices creates a class of novel materials exhibiting superior electrical and mechanical properties which are suitable to replace many existing materials such as those for engineering applications and in electrochemical devices.
Novel material which consists of starch is one of the most common renewable and biodegradable polymers deposited as granule in plants which can be found abundantly in our country. It is composed of repeating amylose and amylopectin.
In this research work, potato starch was chosen to be the polymer host because it has a better morphology in comparison to other starch. Physically, it appeared to be soft flexible film with high conductivity compared to corn starch.
Furthermore, instead of just being a popular food item, potato starch is presently applied in the industrial field as coatings and sizing in paper, textiles and carpets as binders and adhesives, absorbents and encapsulates.
The starch based film is reported to exhibit good mechanical properties. In addition, the dry thin film of starch could also be prepared easily. Ammonium salt was chosen because it does not have a high tendency to break the starch. The thin clear films of potato starch were prepared by solution casting technique.
A certain amount of potato starch (Sigma-Aldrich) was weighed and dissolved in 50ml of acetic acid (Systerm) in a 100mL beaker and left to be stirred for 20 minutes at a certain temperature. Once the cloudy solution turns clear and it is cooled to room temperature. The solution is then doped with various amounts of ammonium salts. Later, these dry thin films were characterized via Impedance Spectroscopy, Fourier Transform Infrared (FTIR), X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM).
Based on the impedance results, the conductivity of starch is low due to no mobile ions provided within the sample. The incorporation of salt increased the conductivity gradually. The higher the concentration of the ammonium salt, it actually attributed to increase in the density number of mobile ions.
The number density of charge carriers’ increased since the rate of ion dissociation has been greater than the rate of ion association. But if the salt concentration is too high, it could increase the influence of the ion pairs and higher ion aggregation, which can reduces the overall mobility and degree of freedom hence decreases the conductivity.
FTIR measurement was used to determine the interactions between salt and the polymer host. In the present work, FTIR spectroscopy was recorded using Spotlight 400 Perkin-Elmer spectrometer in the wavenumber range of 450-4000 cm_1. The FTIR spectra indicates that the complexation between starch and ammonium salt has occurred.
Upon higher concentration of the salt, hydroxyl band shifted to higher wavenumber, this maybe due to the fact that either the excess salt did not dissociate or the ions recombine to form a neutral ion pair which decreases the number of ions. From the x-ray diffractogram, three crystalline peaks are observed thus indicates the pure starch film shows semi crystalline state due to the presence of both sharp and diffuse diffraction peaks.
The fraction of amorphous phase and the charge carriers increase simultaneously with increasing ion concentration. The optimum composition of the green solid electrolyte has the potential to be used as solid electrolyte in electrical devices since it shows maximum conductivity of 10-3 and serve as an ionic conductor.
For further information contact:
UNIVERSITI TEKNOLOGI MARA
INSTITUTE OF SCIENCE (IOS)
Assoc Prof AZIZAH HANOM AHMAD
Strange but true: Turning a material upside down can sometimes make it softer
20.10.2017 | Universitat Autonoma de Barcelona
Metallic nanoparticles will help to determine the percentage of volatile compounds
20.10.2017 | Lomonosov Moscow State University
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research