PVC heat stabilizers commonly used test method

To introduce PVC heat stabilizers are two common test methods. A process called : Torque Rheometer test method ; second is called roll blackening pilot testing method .
PVC heat stabilizers torque  plastic flame retardant rheometer test method
Mimic the actual torque rheometer PVC processing a typical small pilot-type apparatus . Outside of the instrument a closed processing tank , connected to the instrument by the computer can control the machining tank temperature, and within two roll speed , torque rheometer added quality of materials is generally 60 ~ 80 g, depending on the apparatus and different models . Experimental steps of: preparing in advance with different thermal stabilizer masterbatch based on PVC masterbatch formulation , in addition to other ships and ACR, CPE, CaCO3, TiO2, lubricants and the like . Torque Rheometer advance the set temperature , when the temperature rose to specify and steady speed , will be weighed mixture added processing chamber , quickly closed records  aluminium stearate on a computer connected to a variety of parameters , namely flow curve . After processing , you can also get different extrudate physical characteristics , such as whiteness, whether shaping , smoothness and so on. These parameters can determine the corresponding potential industrial heat stabilizers , heat stabilizers suitable shall have suitable torque and plasticizing time of the extrudate should be preferably molded and whiteness, surface smoothing . Torque rheometer in laboratory studies and between industrialized mass production to build a convenient bridge.
PVC heat stabilizers roll blackening test
Determination of thermal stability as a PVC stabilizer for fittings  dynamic effect of a class of helper methods , dynamic two-roll used in the absence of the rheometer , the experiment instrument select double rolled sheet , which together with the high-speed mixed powder , compression molding , the resulting samples were subjected to extruded repeatedly until the black test piece until completely black record time , the time is called blackening . Blackening by comparing the length of time to determine the type of thermal stabilizer effect of the thermal stability of PVC .