TA Instruments ARES rheometers

TA Instruments ARES rheometers measure controlled strain and controlled stress by using two technologies combined motor and transducer (CMT) and separate motor and transducer (SMT). The company s rheometer instrument controls using Ochestrator software include... 

Effects of instrument compliance can induce large errors on shear measurements of elastic and viscoelastic properties of materials [1,2]. These effects are caused not only by the transducer but also the machine itself (load frame), and the rheometer fixtures. We present examples of rheometer compliance effects on the measurement of the material properties of small molecule glass formers and a commercially available polydimethysiloxane (PDMS) rubber. A TA Instruments ARES Rheometer was used with a strain gage transducer (Honeywell-Sensotec). Stress relaxation, aging experiments, and dynamic frequency sweep experiments were performed. We also propose a procedure to correct for comphance effects in stress relaxation experiments and dynamic frequency sweep experiments. Suggestions are made for both instrument and experimental design to avoid and/or reduce compliance effects. 

Three HIPS resins possessing distinct rheological properties were utilized in this study STYRON 1200, 1170, and 484. These resins have melt flow rates (MFR) of 5.0, 2.1, and 2.8 g/10 min (200T05kg) and will be referred to in the paper as HIPS 1, HIPS 2, and HIPS 3, respectively. The dynamic mechanical spectroscopy measurements (viscosity vs. frequency and temperature, loss and storage modulus vs. frequency and temperature) were performed on a TA Instruments ARES rheometer. The measurements were obtained at three different temperatures 170, 190, 210, and 2301C. The uniaxial extensional viscosity measurements were performed at three Hencky rates 0.1, and 10s on a SER (Sentmanat Extensional Rheometer, Xpansion Instruments) at 1701C. 

For the measurements reported here, fluorosilicone films were prepared by casting uncured fluorosilicone gel onto aluminum plates (50 mm in diameter) and then curing at 82°C for 24 hours. The samples were then cooled to room temperature before use. The cured gel films were 0.9 0.05 mm thick. Tack measurements were performed on a TA Instruments ARES G2 rheometer. The probe used was an 8 mm diameter, flat plate fixture. 

Two types of shrink testing were conducted on these films, and these methods are as follows (1) fixed length shrink force testing, and (2) free shrink testing. A TA Instruments ARES-LS rheometer and a TA Instruments Q800 Dynamic Mechanical Analyzer (DMA) were employed, respectively, to perform these two shrink tests. The rotational rheometer (ARES-LS) was used to conduct the fixed length shrink force test. In this test, the length of the film was fixed and the normal force was... 

The friction coefficient at PVA gel/OTS modified quartz is 0.300 while that at PVA gel/unmodrfied quartz is 0.076. Frictions were measured by using a rheometer (ARES, TA instruments) as a function of sliding velocity in water and these values were calculated from the experimental resultsoflowestsbdingvelodty,7.5 x 10 m/s. 

The flow curves can be established for different concentrations and different molar masses of HA samples, and at different temperatures for a better insight into the molecular properties of polymers. Fig. (14) shows results of a series of rheological tests of HA polymers with different molar masses at different concentrations. Fig. (14, left panel) shows the flow curves for three different HA samples with the Mw values of 850 kDa, 600 kDa, and 400 kDa. Fig. (14, right panel) exhibits the flow curves for an HA sample at four different concentrations ranging from 0.11% to 2.16%. The flow curves are obtained by using an AR 2000 stress-controlled rheometer from TA Instruments (New Castle, DE, USA). A cone/plate geometry is used. The rotor was made of the acrylic material, 4 cm of diameter and 1° of cone angle. The measurements were performed at 20 °C. 

DMA was performed by a rheometer ARES G2 from TA-instruments in torsion mode with a heating rate of 5 K/min and a frequency of 1 rad/s (6.28 Hz) as well with a dynamic mechanical spectrometer EPLEXOR 150N from GABO QUALIMETER Testanlagen GmbH, Germany in tensile mode with a heating rate of 3 K/ min and a frequency of 1 Hz. 

In this chapter, the major benefits of MTDSC to characterise reacting polymer systems are highlighted, with a special focus on polymer network formation. All MTDSC experiments shown are performed on TA Instruments 2920 DSC equipment with the MDSC accessory. Dynamic rheom-etry measurements were made with a TA Instruments ARIOOO-N rheometer in parallel plates mode using disposable aluminium plates. 

Low-force tabletop instruments are offered by the traditional thermal analysis vendors Mettler Toledo, Netzsch, Perkin-Elmer, and TA Instruments as well as Seiko Instruments. Higher-force tabletop and floor model instruments are offered by Bose and OldbMetrovib. Rotational rheometers that also perform torsional shear measurements on solid samples are marketed by Reologica... 

Parenchyma and trachea taken from pig s lung that was dead within 48 hours were tested using Rheometer, made by TA-Instrument of AR550 model. Test pieces temperature was kept constant at 36-[C], Results for this test are shown in figure 5. 

The setup of all experiments is illustrated in Fig. 20.13. The main device is the rheometer DHR-1 of TA instruments. An air bearing and a magnetic bearing are used to minimize the friction of the rotation of the geometry. The low viscosity of... 

LAOS measurements for two samples, a polyisoprene melt (abbreviated PI-84k, Mw = 84,000 g/mol, PDI = 1.04) and a 10 wt% solution of poly isobutylene (abbreviated PIB, Af = 1.1 xlO g/mol) in oligoisobutylene, were conducted on four different rheometers. The first two were separated motor transducer(SMT)-rheometers, namely the ARES-G2 (TA Instruments) and the ARES-LS (TA Instruments) with a IKFRTNl transducer. The DHR-3 (TA Instruments) and the MCR501 (Anton Paar) are in principle stress controlled instruments, but can be used for strain controlled experiments when using the deformation control feedback option (called continuous oscillation for DHR-3 and direct strain oscillation for MCR501). 

The mechanical properties of frozen materials can be difficult to study due to the enormous stiffness and moduli involved and the fact that changes can occur rapidly over small temperature ranges. The Ares rheometer (Rheometrics Corporation/TA Instrument, Delaware, USA) has a wide range of modulus measuring capability and has been used in the oscillating plate mode in studies of sugars at comparatively low moisture contents (15% —10°C) with and without hydrocolloids [141]. 

The experiments carried out by Shi et al. were stress relaxation, aging, and dynamic (all in shear) using a torsional rheometer, an Advanced Rheometric Expansion System (ARES, TA Instruments). The Honeywell-Sensotee load eell had a capacity of 20,000 g-cm in torque and 5,000 g-cm in normal force. Some of the experiments were reproduced in refermces [5] and [6]. The platen diameter for all repeated experiments on glycerol, m-toluidine and sucrose benzoate were performed using 3 mm radius platens made of aluminum. The chemicals were the same as used in reference [3]. Temperature stability and sample geometry are reported in [5] and [6]. 

AR Series Rheometers These are a group of rheometer systems that measure viscoelastic data for both fluids and solids. The AR series is a sequel to the former rheometrics rheometers with updated performance and efficiency. The instruments feature sensitive low-torque performance, accurate stress, direct strain control, and intuitive software. There are three AR series models in addition, TA offers the ARES-G2 rheometer, which is a research instrument. Each instrument has different features and torque ranges. The newest of the group, the ARG-2 instrument, has a magnetic drive that provides enhanced low-torque precision and accuracy. 

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