Papers by Keyword: Torque Rheometer

Abstract: Nanocomposites of polyamide-6 with nanoSiO₂ surface modified by 3-aminopropyltrimethoxysilane (3-APTMS) were prepared by melt blending in torque rheometer. Chemical modification of nanoparticles surface with 3-APTMS were observed by FTIR. Prior to nanocomposites processing, neat polyamide-6 (PA-6) was processed in a torque rheometer with varying processing parameters: polymer residence time in the chamber, rollers rotational speed, and polymer filling volume in the chamber. Two levels for each parameter were fixed. The influence of these parameters on degradation of PA-6 was determined by dilute solution viscosity and capillary rheometry. Results indicate that the best condition was achieved with the higher polymer residence time in the chamber, the higher rollers rotational speed, and the higher polymer filling volume in the chamber. With this information, PA-6 pellets were mixed with nanosilica particles unmodified and surface-capped by 3-APTMS via melt blending in torque rheometer, obtaining PA-6 composites with 1 wt.% of nanofillers. Mechanical and thermal properties of nanocomposites were evaluated by means of tensile test and differential scanning calorimetry (DSC).

Abstract: By using of the principle of the reverse engineering and CATIA V5 software, the torque rheometer mixer rotor used in high polymer material test is designed. The POWERMILL software is used for NC programing and manufacturing simulation, the MIKRON UCP710 five axis linkage processing center is used for manufacturing. The practical application of this rotor on torque rheometer proves that this rotors structure design is reasonable. The test requirement of torque rheometer is well satisfied. This kind of rotor has a very good promotion value.

Abstract: A method to evaluate the rheological properties of low density polyethylene (LDPE) using torque rheometer was developed and the parameter of Power rate model were obtained by fitting balance torque and balance temperature. The rheological parameters of polymer melts were evaluated on the basis of previous equation by introducing the apparent filling degree in torque rheometer, the results show the temperature compensated torque (M_tc) increase from 5.685 Nm to 6.972 Nm, while apparent filling degree change from 0.65 to 0.85 at the rotor speed of 29.98 rpm. The M_tc also increase from 2,900 Nm to 3.528 Nm and increase by 0.628 Nm at the rotor speed of 4.985 rpm, while it increase by 1.287 Nm from 5.685 Nm to 6.972 Nm at the rotor speed of 29.99 rpm, which means the higher the rotor speed, the more influence on the torque. The other relative rheological parameters, such as the activation energy (ΔE), the Non-Newton (n), etc., calculated in this model, indicate the effect of apparent filling degree on the polymer melting rheology. The calculated values were compared with those derived from capillary rheolometer, the results show the apparent viscosity decrease with the increase shear rate in exponential function, the change rules of apparent viscosity are good agreement from two kinds test methods.

Abstract: This paper presents a new distributed control system used in torque rheometer. It can overcome shortcomings in traditional control system of torque rheometer and optimize overall performance of the system. The measurement and control system was designed by modeling method. The enhanced PID control algorithm and integration separation digital PID control algorithm were adopted to improve dynamic response characteristics. The Modbus communication protocol was selected as data link layer protocol of communications network. The monitoring software was developed by Visual Basic. A large number of experiments demonstrate that the stability of system is improved greatly and maintenance and extension of instrument become easier.

Abstract: A detailed experimental research on the rheological measurement by torque-rheometer (TR) based on a measuring model established by former researcher is presented. The influence of measuring conditions, material type and rotor geometric were discussed. Measuring results from the torque-rheometer were compared with those from capillary rheometer. It’s confirmed that under certain measurement conditions, torque-rheometer can accurately measure the melt rheological properties of polymer composites or blends. Measuring conditions and material type have little effect on the results accuracy. The rotor geometry has great impact on the reliability of measurement.

Abstract: A new type of torque sensor system used in torque rheometer is designed. Precision and reliability is analyzed by virtual prototyping simulation. Simulation shows that the system error increases with the backlash increasing. So the gearhead must have some certain precision demand. The torque sensor components are developed on the basis of simulation. The experiment shows that this measure system does not use active part, so it does not need to maintenance, and the reliability is high. The temperature and outside stress influence and hysteresis error are eliminated. The torque sensor system measure precision is better than 0.1% F.S.