You are currently viewing only those items made visible to the public. Sign in here with your UCL username and password to view the full catalogue.
|CONTACT 1||Jonathan Knowles|
|Enquire about this item|
|SITE||Eastman Dental Institute|
Typical Applications For Which The DMA 7e Is Used Polymers And Composites Quality factor/tan delta Impact performance Effects of filler, modifiers, blending, grafting, and copolymerization Heat set Strength Effect of drying Effect of heating Effect of chemicals, solvents, or humidity Effect of stress or pressure Stiffness/Modulus Glass transition Fiber/Film Shrinkage, Orientation Food/Pharmaceutical - Effect of additives Biological/Environmental - Effect of aging, drying, or sunlight
The Perkin-Elmer DMA 7e is used for mechanical analysis of solid and near-solid samples. It measures mechanical properties such as modulus (elasticity) and viscosity (damping) as a function of time, temperature, frequency, stress, or combinations of these parameters. The DMA 7e provides the performance and flexibility necessary for the characterization of a broad range of materials, from soft samples such as elastomers, thin films, and single filament fibers to hard samples like composites, ceramics, and some metals. The DMA 7e can also apply a constant force to perform standard thermomechanical analysis (TMA). Comprehensive calibration, verification, and validation assure the highest confidence in results reported by the DMA 7e. It has been certified to perform standard test methods defined by international organizations including ASTM and ISO. Force Control- Force motors are used to cause the sample to deflect. Precise force control is critical to obtaining accurate modulus results. The DMA 7e force motor can accurately control from very low forces for the analysis of samples in the molten or flowing state to high forces for the analysis of very high modulus solids. Forces can be calibrated and verified using traceable mass standards providing traceable modulus results. Displacement Sensitivity- Displacement sensors are used to measure sample deflections. High displacement sensitivity is important for characterizing a wide variety of sample types from polymer pellets to single filament fibers and thin films. High dynamic displacement sensitivity allows measurement of subtle mechanical transitions. Long static displacement range allows the sample to expand or contract many times its original size, up to 300%. Furnace Systems- Two furnace systems are available for use with the DMA 7e. These systems allow DMA measurements over the range of 170°C to 1000°C. Based on a resistance-heating design, these furnace systems allow continuous monitoring and temperature control, resulting in improved accuracy and reproducibility. Low-mass design permits rapid cool-down at the completion of an experiment, often requiring only a few minutes to cool back to the starting temperature. Fast-cooling experiments are best performed with the DMA 7es unique quartz measuring systems. The result is that you can run more samples and characterize more materials. The precise temperature control features of this furnace allow heating and cooling rates from 0.1°C/min to 100°C/min. Sample Types and Geometries- The practical advantages of the DMA technique have expanded to almost every material and sample type. It is not uncommon for a single laboratory to test raw materials, intermediate products, and finished products to verify materials and end-use performance. To accommodate this broad range of sample types and test geometries, numerous measuring systems have been developed for the DMA 7e. These systems are designed to handle materials in a variety of geometries, from semisolids in the form of flat bars, pellets, cylinders, disks, films, and even fibers. Included are Extension Analysis systems for the analysis of thin films and fibers; 3-Point Bending, Dual Cantilever, and Single Cantilever systems for the analysis of a variety of thermoplastics and thermosets; and nine different Parallel Plate systems Frequency Range- With a frequency range of 0.01 to 50 Hz, the DMA 7e provides a valuable tool for the characterization or fingerprinting of materials. Frequency scanning provides a convenient way to observe differences between materials as a result of long and short chain branching, chain entanglements, and molecular weight distribution differences. Frequency scanning also provides a means for calculating the zero shear viscosity or for identifying the Newtonian region in polymers, which may then be applied to molecular weight calculations. Lower frequency data, such as one cycle per day or one cycle per week, is generated through creep recovery tests.
Item ID #.
Last Updated: 16th January, 2014