QUALITY POLICY
In the products we provide; keeping customer satisfaction at the highest level and improving the processes with continuous control constitute the basis of our quality policy.
Our quality policy;
Our mission is to work with all our strengths in order to be an organization that is trusted in terms of quality in our sector.
Vicat Analysis
ASTM D 1525'e according to the standard, such as polystyrene, a certain melting point of the material for the determination of the softening temperature is an analysis.
A 1 mm2 diameter needle is placed on molded polystyrene. A weight is added to the needle to apply 10 Newtons force and the sample is immersed in the heating bath. The heating bath is slowly heated to a temperature of 2 ° C per minute. The material will start to soften with increasing temperature. The temperature when the needle is inserted into the 1mm sample is called the vicat softening temperature. Glass transition temperature: It is the temperature limit at which the substance loses its glassy properties and starts to gain viscous properties, in short it is the starting point of the workability temperature.
Heat Deflection Temperature
According to ASTM D 648 standard method, it is used to determine whether the polystyrene is exposed to temperature and to determine the temperature limit of the materials.
The molded polystyrene is placed between two supports in the range of 100 mm. The weight of the sample is calculated according to the sample size. For this reason, the stability of the sample dimensions is very important. Otherwise, the amount of weight specified in the method must be changed continuously. The applied force is 0,45 MPa. The sample is then immersed in the heating bath. The heating bath is slowly heated to a temperature of 2 ° C per minute. The material will start to soften with increasing temperature. The temperature at which the sample is tilted at 0,26 mm is called the HDT temperature.
Izod Impact Resistance Test
According to ASTM D 256ıe standard, it shows the amount of energy absorbed by the sample by the free impact of the 2.75 J pendulum arm to the polystyrene sample. It is used to determine the strength of polystyrene. Unit is joule / meter. After the samples are molded, the sample is tested after notching.
Tensile Test
According to ASTM D638 standard method, tensile test is used to determine the mechanical properties of materials.
In the tensile test, the resistance of a material against a static and slow applied load is measured. A suitable tensile test sample is placed on the test machine and force (load) is applied to the sample. In the tensile test, the elongation in the material is measured by the extensometer, and the applied force (load) by the load cell (loadcell), and by using the measured elongation and load values, the stress-strain curve is obtained. With the tensile test, it can be determined how long the materials are elongated and which elongation strength are based.
The results obtained from the test are used to estimate the material selection, quality control and how the material will behave under other forces for any application. Information obtained directly through this test; properties such as tensile stress, elongation, yield strength, tensile strength are determined.
Flexural Test
According to the ASTM D790 standard method, the flexing test is used to determine the mechanical properties of the materials. This feature can also be called bending strength.
During the test, the material is fixed at 2 points and the force is applied to the material from a point in the middle of these two points. The force in which the material changes in the material or the material is broken shows the resistance of the material against bending. During this analysis, the bending modulus of the material is also calculated. The flexural modulus is indicative of the flexibility of the material. The more flexible the material, the lower the modulus value.
Determination of EPS Particle Size
In the EPS unit, the analysis is carried out to determine the% distribution of the diameter of the EPS granules in the packed product from the Reactor outlet, the sieves and the packed product.
Gas Chromotography
Chromotography is a method of separating substances present in a mixture. The type of chromatography used to differentiate between gas phase substances is called gas chromatography.
There are two different gas chromatography in our laboratory;
Basically, the study logic of gas chromatography is as follows;
In liquid-gas chromatography, the needle (needle entry) portion is used to vaporize the liquid sample.
It is heated to a suitable temperature, taking into account the boiling point and decomposition temperatures of the substances in the injected sample. In this way, the liquid injected into the lumen is evaporated. The gas phase sample is transported to a separation gas by a non-reacting gas with other chemicals such as Nitrogen or Helium.
The tube has a glass tube. Glass wool is placed into the glass tube and the possible solid impurities that may come from the sample are placed in the column so as not to be blocked. The septum is located at the point where the needle enters. Septum resembles a flexible seal. This septum is used to prevent gas leaks. It is deformed because the needle is in and out. Periodically changed.
In solid-gas chromatography, Headspace is used to vaporize the volatile chemicals in the solid sample. The solid sample is placed in the glass tube and the mouth is closed with septum. Septum is to prevent gas from escaping from the tube. Check that the glass tube opening is properly closed. Glass tube temperature is maintained in a set oven, volatiles in the sample is allowed to evaporate to the gas phase. The sample in the gas phase is transported to a separation column by a gas that does not react with other chemicals such as Nitrogen or Helium.
Separation of Gas in the Separation Column:
Columns are the most important part of the system. Separation takes place here. The success of the separation process depends largely on the selection of the appropriate column. Capillary columns are used in gas chromatography. The capillary columns are open tubular. The inner surface of said tube is coated with chemicals for solid separation. The second important issue for decomposition is column temperature. In order to achieve this, the column is placed in an oven with thermostat. The column temperature varies depending on the sample being studied and the degree of separation required.
The chemicals entering into the column are kept by the filling material inside the column. These retention times are different for each chemical. Due to the fact that these times are different, some chemicals move quickly in the column or pass behind by slow motion. By using these properties, it is ensured that the chemicals are separated from each other.
Translating the Amount of Incoming Gas to the Detector:
FID (Flame Ionizer) detectors are used in gas chromatography equipments used in our laboratory. The sample coming from the detector is burned by the help of flame and the flame intensity is converted to the spindle.
Hydrogen and dry air are used to provide combustion. Hydrogen and dry air mixed in certain proportions are removed by sparking.
Interpretation of the chromotogram:
The chromotogram example is as shown above. The X-axis represents the time, and the y-axis refers to the signal strength as the spindle volts. The first chemical on the detector will come first to the detector will take the first place on the left side of the chromotogram. The chemical that moves more slowly in the column takes place at the end on the right side of the chromotogram for the most recent on to the detector.
The device program calculates the area under the peaks. As the amount of space increases, the combustion time of the chemical in the detector will increase. Therefore, the amount in the mixture will increase in proportion to the peak area. By using this principle, the unknowns in the chemical mixtures are defined and their quantities are determined.
UV-VIS Spectrophotometer
Ultraviolet and visible light (UV-Vis) absorption spectroscopy is a measure of the reduction in the intensity of a light beam after passing through a sample. A decrease in the intensity of light indicates that absorption is increased. Many molecules absorb UV or Vis wavelengths and different molecules absorb light at different wavelengths. By utilizing this feature, the amount of substance in the chemical mixtures can be determined. For example, the amount of chemical required to be detected is measured by measuring the absorption of a specific wavelength.
The working principle of the spectrophotometer is as shown in the figure. The light source is passed through a slot to the dispensing device (monochromator). The monochromator sets the wavelength from the light and sends it to the outlet slot. The light passes through the sample and reaches the detector. The detector measures how much intensity is absorbed from the light source. In this way, the amount of absorption is measured.
In our laboratory, the amount of TBC and polymer in styrene monomer samples is determined.
Hunter Flex Color Detection Device
In this device, 3 different color values of the injection molded GPPS and HIPS samples are measured (L, a, b). The L value refers to the brightness levels from 0 to 100 (Black and White). As the L value increases, the dimmer increases as the brightness increases. a means the red or green. When A value is positive, redness increases in the sample and negative movement increases the greenness. The b value refers to jaundice or blue. When B color increases in positive direction, jaundice increases. In the negative direction, the blueness increases.
Melt Flow Index Test (MFI)
The chain length increases as the styrene monomer is added to the end of the chain. Reduces MFI.
The most common analysis in our laboratory. MFI (Melt Flow Index) Melt Flow Tester refers to Mass Melt Flow Rate of thermoplastic materials according to ASTM D1238 standard method.
The melt flow rate increases or decreases inversely with the chain length of the polymer. For example, the GPPS 603 product with a low melt flow rate has a polymer chain length. For GPPS 615, although the MFI value is high, the chain length is shorter.
The polystyrene pellets are squeezed into the hot tube at 200 0C. The device piston is placed on it. Preheat time is expected to melt the polymer. After the preheating time has been completed, 5 kg of weight is placed on the piston to allow the polymer to flow from the orrifice (Die). The measurement lines on the piston are expected to start the measurement. The test is started when the piston comes into the measuring line.
The device will automatically cut off the flowing polymer. According to the product type 60 or 30 sec. then a cut is done. The amount of material flowing in 10 minutes is calculated by placing the sample cut in this range on the balance.