Plastic has countless applications. Take a look around you, you would find most of the things around you are made up of plastic. Due to its flexible molecular structure, the moulding becomes extremely easy. Apart from this, other properties like good tensile and compressive strength, impact strength are making plastics favourite among diverse industries. Before choosing the plastic as raw material, it is important to identify its properties first. The vendor, however, assures the manufacturer about the quality, but it not bad to cross check things at manufacturer’s end to avoid any failures later.
Moisture Analysis – Some plastic granules have the tendency to absorb moisture from the surrounding. These moist granules are difficult to process. Thus, it is important to analyse the moisture absorbing behaviour of the plastic. Moisture analyser is a table top device which is equipped with a scale and a halogen bulb for heating. The sample is tested in powder or granulated form. The end product cannot be tested into it, as it is specifically designed for testing of raw material. The sample is kept in the pan and allowed to rest there for some time. The scale measures the weight before the heating. The halogen bulb gets activated and heats up the sample until the moisture evaporates completely. The difference in weight before and after the test is the moisture content.
Impact testing – For impact testing, there is a need to prepare the sample first. You cannot test it on the raw material in its original form. A rectangular strip is made out of the selected material. A V-notch is carved in the centre of it. Impact testing is done in 2 ways. Izod impact and Charpy impact. In Izod test, the sample is placed in vertical position and the notch is facing backwards. Izod and Charpy impact tester have a pendulum aligned at an angle of 150°. The pendulum which is resting at a plunger stored potential energy. As you made the pendulum to fall free on the sample, this potential energy gets changed into kinetic energy. The impact with which it hits the pendulum is measured by the machines and displayed.
Melt Flow Index – The rate of flow of the molten plastic in 10 minutes is measured in this test. MFI tester has a heater to melt the granulated plastic. A plastic thread like a string of molten plastic comes out from the orifice. After 10 minutes the output from the orifice is taken and weighed. The values are fed into the machine and Melt Flow Index will be displayed.
For more information about Izod and Charpy Impact tester, MFI tester and Moisture Analyser, contact us.