Edi Sanjaya

Poly (vinylidene fluoride) Thin Film Prepared by Roll Hot Press

Various methods have been developed in the manufacture of Poly (vinylidene fluoride) (PVDF) thin films such as coating, spreading, evaporation and calendaring. The method of making this film certainly has many advantages and disadvantages as in the case of operational processes and also the cost of the required treatment. In this paper, an alternative method to preparation of PVDF thin films has been done through the development calendaring method by using roll hot press. The advantages of roll hot press are simple in terms of operation and relative low cost. PVDF thin film has been produced for several temperatures of roll hot press with several different thicknesses. The PVDF thin films are characterized using X-Ray Diffraction and IR spectra. In addition to determine the surface resistivity are caried out using I-V meter. We found that an increase in β fraction of PVDF thin films with increasing temperature at fixed film thickness, while the surface resistivity of PVDF film are decreased. This shown that the piezoelectric property of PVDF films has been

Effect of mechanical treatment and fabrication temperature on piezoelectric properties of PVDF film

Piezoelectric properties are one of the electrical properties that will arise in case of mechanical disturbances. One of polymer that can produce the greatest piezoelectric properties is poly vinylidene fluoride (PVDF). Piezoelectric properties of PVDF can be improved by mechanical treatment on the varying film thickness and the temperature. PVDF film has produced by roll hot press tool. Furthermore, PVDF films were characterized by XRD, IR and I-V meter. We have been obtained an increase piezoelectric properties of PVDF films that characterized by increasing β fraction. We get β fraction was 63.63%, 66.35% and 71.60% for temperatures of 140, 150 and 160°C, respectively at film thickness of 13 µm. In addition, We have gained β fraction for the thickness of 15, 13 and 8 µm are 64.60%, 66.35% and 69.00%, respectively at temperature of 140°C. This is due to the increasing temperature and decreasing film thickness then more dipoles are oriented in PVDF films. These results indicate that mechanical treatment c...

Development of Ground Displacement Sensor based on Flat Coil Element for Detection of Landslide

This paper presents the development and characterization a low cost, robust and reliable ground displacement-based flat coil sensor for application of landslide detection. Flat coil element has been made from a thin epoxy and silver mixed with a number of coils 30, diameter of 3 cm and inductance 9.2 μH. The measurement static characteristic of sensor showed that the sensor output voltage increases with increasing distance between the seismic mass to the sensor and vice versa. Flat coil-based sensors have a working area between 0.6 to 10 mm with the absolute and the relative error of 0.035 mm, 0.81 %, respectively. The dynamic characteristic of sensor system is able to detect the ground shifting in the direction of the horizontal and vertical in the range (0-15) mm and (0-20) mm, respectively.

The low frequency 2D vibration sensor based on flat coil element

Vibration like an earthquake is a phenomenon of physics. The characteristics of these vibrations can be used as an early warning system so as to reduce the loss or damage caused by earthquakes. In this paper, we introduced a new type of low frequency 2D vibration sensor based on flat coil element that we have developed. Its working principle is based on position change of a seismic mass that put in front of a flat coil element. The flat coil is a part of a LC oscillator; therefore, the change of seismic mass position will change its resonance frequency. The results of measurements of low frequency vibration sensor in the direction of the x axis and y axis gives the frequency range between 0.2 to 1.0 Hz.

Glucose Sensing Using Capacitive Biosensor Based on Polyvinylidene Fluoride Thin Film

A polyvinylidene fluoride (PVDF) film-based capacitive biosensor was developed for glucose sensing. This device consists of a PVDF film sandwiched between two electrodes. A capacitive biosensor measures the dielectric properties of the dielectric layers at the interface between the electrolyte and the electrode. A glucose oxidase (GOx) enzyme was immobilized onto the electrode to oxidize glucose. In practice, the biochemical reaction of glucose with the GOx enzyme generates free electron carriers. Consequently, the potential difference between the electrodes is increased, resulting in a measurable voltage output of the biosensor. The device was tested for various glucose concentrations in the range of 0.013 to 5.85 M, and various GOx enzyme concentrations between 4882.8 and 2.5 million units/L. We found that the sensor output increased with increasing glucose concentration up to 5.85 M. These results indicate that the PVDF film-based capacitive biosensors can be properly applied to glucose sensing and provide opportunities for the low-cost fabrication of glucose-based biosensors based on PVDF materials.

A comparative study of flat coil and coil sensor for landslide detection

The landslide is one of the most costly catastrophic events in terms of human lives and infrastructure damage, thus an early warning monitoring for landslides becomes more and more important. Currently existing monitoring systems for early warning are available in terms of monolithic systems. This is a very cost-intensive way, considering installation as well as operational and personal expenses. We have been developing a landslide detection system based on flat coil and coil sensor. The flat coil element being developed is an inductive proximity sensor for detection mass of soil movement. The simple method of flat coil manufactures and low cost, is an attraction that is still inspired to develop flat coil sensors. Meanwhile, although it has a drawback in terms of their size, the coil sensor is still required in many fields due to their sensitivity and robustness. The simple method of coil manufacture and the materials are commonly available and low cost, is an attraction that is still inspired to develop induction coil sensors. A comparative study of alternative configuration of sensor based on flat coil elements and a coil in application to landslide detection has been discussed in this paper. The purpose of this comparison is to show the ideal conditions and the challenges for each sensor. Furthermore, a comparison between flat coil and coil sensor is presented.The landslide is one of the most costly catastrophic events in terms of human lives and infrastructure damage, thus an early warning monitoring for landslides becomes more and more important. Currently existing monitoring systems for early warning are available in terms of monolithic systems. This is a very cost-intensive way, considering installation as well as operational and personal expenses. We have been developing a landslide detection system based on flat coil and coil sensor. The flat coil element being developed is an inductive proximity sensor for detection mass of soil movement. The simple method of flat coil manufactures and low cost, is an attraction that is still inspired to develop flat coil sensors. Meanwhile, although it has a drawback in terms of their size, the coil sensor is still required in many fields due to their sensitivity and robustness. The simple method of coil manufacture and the materials are commonly available and low cost, is an attraction that is still inspired to develop...

Design and Development of Instrument for Measuring Torque and Shear Modulus for Material Research

An Instrument for measuring torque and shear modulus based on flat coil element for material research has been developed. Flat coil element was made from a thin epoxy with number of coils 30 and outer diameter of 3 cm. Working principle of the sensor is based on position change of a disturb element which attached to test shaft in front of the flat coil. The change of position will change the total inductance of the sensor system. The change of inductance is measured using LC oscillator by measuring its resonant frequency. An F/V converter converts the resonance frequency into voltage. The flat coil is used to measure the change of angle of the developed torque instrument. Using microcontroller ATMEGA16 the developed instrument can be controlled and work automatically. The developed instrument can measure torque and shear modulus with relative error less than 3%

Effect of roll hot press temperature on crystallite size of PVDF film

Fabrication PVDF films have been made using Hot Roll Press. Preparation of samples carried out for nine different temperatures. This condition is carried out to see the effect of Roll Hot Press temperature on the size of the crystallite of PVDF films. To obtain the diffraction pattern of sample characterization is performed using X-Ray Diffraction. Furthermore, from the diffraction pattern is obtained, the calculation to determine the crystallite size of the sample by using the Scherrer equation. From the experimental results and the calculation of crystallite sizes obtained for the samples with temperature 130 °C up to 170 °C respectively increased from 7.2 nm up to 20.54 nm. These results show that increasing temperatures will also increase the size of the crystallite of the sample. This happens because with the increasing temperature causes the higher the degree of crystallization of PVDF film sample is formed, so that the crystallite size also increases. This condition indicates that the specific volume or size of the crystals depends on the magnitude of the temperature as it has been studied by Nakagawa.