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Thermal Analysis Excellence
Flash DSC 1 STARe System Innovative Technology Versatile Modularity Swiss Quality
Flash Differential Scanning Calorimetry for Research and Development
Flash DSC Excellence
A Quantum Leap in Innovation Opens up New Frontiers Differential Scanning Calorimetry, DSC, is the most important method in thermal analysis. It measures the heat flow to or from a sample as a function of temperature or time and thereby allows physical transitions and chemical reactions to be quantitatively measured. The Flash DSC 1 revolutionizes rapid-scanning DSC. The instrument can analyze reorganization processes that were previously impossible to measure. The Flash DSC 1 is the ideal complement to conventional DSC. Heating rates now cover a range of more than 7 decades. Features and benefits of the Flash DSC 1: n Ultra-high cooling rates – allow materials with defined structural properties to be prepared n Ultra-high heating rates – reduce measurement times and suppress reorganization processes n Fast response sensor – enables the kinetics of extremely fast reactions or crystallization processes to be studied n High sensitivity – low heating rates can also be used; scan rates overlap with those of conventional DSC n Wide temperature range – measurements can be performed in the range -95 to 450 °C n User-friendly ergonomics and functionality – sample preparation is quick and easy
The Flash DSC 1 allows you to prepare samples with defined structures such as occur during rapid cooling in injection molding processes. The application of different cooling rates influences the crystallization behavior and structure of the sample. The use of high heating rates enables materials to be analyzed without interference from reorganization processes – there is no time for such processes to occur. The Flash DSC 1 is also the ideal tool for studying crystallization kinetics.
The heart of the Flash DSC 1 is the chip sensor based on MEMS technology. MEMS: Micro-Electro-Mechanical Systems 2
MEMS-Based DSC Sensor Technology Unsurpassed Heating and Cooling Rates In conventional DSC instruments, the sample is measured in a crucible in order to protect the sensor. The heat capacity and thermal conductivity of the crucible however have a significant influence on the measurement. In the Flash DSC 1, the sample is placed directly onto the MultiSTAR chip sensor. The patented dynamic power compensation control circuit allows measurements to be performed with minimum noise level at high heating and cooling rates. MultiSTAR UFS 1 Sensor The Full Range UFS 1 sensor has 16 thermocouples and exhibits high sensitivity and excellent temperature resolution. The MEMS chip sensor is mounted on a stable ceramic substrate with electrical connections. Sensitivity The high sensitivity results from the use of 16 thermocouples, 8 each on the sample and reference sides. The thermocouples are arranged symmetrically around the sample measurement area in the form of a star so that temperatures are measured with great accuracy. The outstanding sensitivity means that measurements can also be performed at low heating and cooling rates. Temperature resolution The temperature resolution is determined by the time constant of the sensor. The smaller the time constant, the better close-lying thermal effects can be separated. The time constant of the Flash DSC 1 is about 1 millisecond or about 1 000 times less than that of a conventional DSC instrument. Baseline The revolutionary multiple temperature measurement around the sample guarantees excellent accuracy. The high degree of symmetry of the differential sensor results in flat and extremely reproducible baselines.
Reusable chip sensors Samples are positioned directly on the sensor. Used sensors can be stored in the chip sensor box supplied so that further measurements can be performed later on if needed. It takes less than a minute to change a sensor.
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Swiss Quality
Flash DSC 1 from METTLER TOLEDO the Fastest Commercial DSC
Sensor environment The sensor support is heatable. In the low-temperature operation, the sensor support can be brought to room temperature before the sensor is inserted. This prevents the gold contact pins from icing over.
Terminal The large easy-to-read color touchscreen terminal at the front of the Flash DSC 1 indicates the status of the instrument. If the instrument is not next to your PC, you can enter individual sequences and queries directly via the terminal.
Complete thermal analysis system A complete thermal analysis system comprises four different measurement techniques. Each characterizes the sample in a different way. The combination of all the results simplifies interpretation. Besides heat flow measurements using DSC or Flash DSC, the other instruments measure weight loss (TGA), change in length (TMA) or the mechanical modulus (DMA). All these quantities change as a function of temperature.
DSC
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Flash DSC
TGA
TMA
DMA
Ergonomic Perfection Is What Customers Value Perfect ergonomics The preparation and insertion of a sample is performed sitting comfortably in front of the instrument. The sample is first cut to size on a small glass microscope slide placed over the sensor. A suitable sample specimen is then transferred directly to the sensor and positioned using a hair.
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Sample preparation Sample preparation is carried out using a microscope. The microscope is also used to accurately position the very small sample specimen on the sensor.
Application Handbook
Thermal Analysis in Practice Collected Applications
Important support services METTLER TOLEDO prides itself in supplying outstanding instruments together with the support needed for you to be successful in your field of work. Our well-trained engineers are ready to help you in any way possible: • Service and maintenance • Calibration and adjustment • Training and application advice • Equipment qualification METTLER TOLEDO also provides comprehensive literature on thermal analysis applications.
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Innovation
Unbelievable Performance Leads to New Results Measurement principle High heating or cooling rates are only possible when the sample is sufficiently small and is in good thermal contact with the sensor. In the first heating run, the sample melts. Thermal contact with the sensor is thereby greatly improved. Defined sample structures can then be produced by varying the cooling rate over a wide range.
Temperature
Sample preparation
Formation of sample structure
Analysis
Melting of the sample optimizes thermal contact.
Different cooling rates allow defined sample structures to be formed.
High heating rates suppress the reorganization of the sample. It can therefore be measured “as received”.
Time
In the second heating run, the sample has no time to reorganize because of the very high heating rates. The enormous range of cooling and heating rates allow many different sample structures to be measured in one experiment.
Chip sensor principle The sample and reference sides of the sensor each have two thermal resistance heaters which together generate the desired temperature program. The smaller heater is for compensation control (dynamic compensation control). The heat flow is measured using the two sets of 8 thermocouples arranged symmetrically around the measurement area on the sample and reference sides of the sensor.
1. Ceramic plate 2. Silicon frame 3. Connecting wire
4 Resistance heater 5. Aluminum plate (sample area) 6. Thermocouple
Homogeneous temperature distribution The sample measurement area of the chip sensor is made of silicon nitride and silicon dioxide coated with a thin layer of aluminum. This provides in an extremely homogeneous temperature distribution across the sensor. The small active measurement area is approximately 2.1 µm thick so that the time constant is mainly determined by the sample.
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Optimized Evaluation Software Brings Efficiency into the Laboratory Software support In a typical Flash DSC experiment, the measurement results are analyzed as a function of the heating or cooling rate or the isothermal time. The experiment is usually performed very quickly. Sample preparation needs somewhat more time. Evaluation and interpretation takes longest but is at the same time the most interesting part of the work.
The STARe software has been expanded to include new requirements. For example, complex measurement programs are set up within a few minutes and large numbers of curves can be efficiently evaluated.
n Selection of curve segments – On opening the measurement, you choose only the curve segments of interest. n Multicurve evaluation – Select the curves, click the evaluation and the individual results are immediately available. n Rapid set up of function table with fit functions – Activate the result line: One click copies all the selected results into a table. Now choose the fit function and the evaluation is completed.
Reorganization of polyethylene terephthalate (PET) Many polymers exhibit reorganization effects in the DSC measurement curve when they are heated. The curve does not therefore show the melting of the crystallites originally present in the sample. This is demonstrated using a sample of PET that had been allowed to crystallize at 170 °C for 5 min before cooling to room temperature. The measurement curves at heating rates between 0.2 K/s and 1 000 K/s show two peaks. The peak at lower temperatures shifts to higher temperatures with increasing heating rate (blue arrow). This peak occurs when the original crystallites melt. The high-temperature peak shifts to lower temperatures (red arrow). This peak is due to the melting of crystallites produced through reorganization during the measurement. Only one peak is observed at 1 000 K/s. Practically no reorganization occurs from this heating rate onward.
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Modularity and Expansion Many Options Microscope options You can adapt the microscope attachment according to your needs. There are two options: 1. Not modular, but excellent value 2. Modular, with adjustable viewing angle, different illumination possibilities, and cameras.
ErgoModule®
Camera kit
Binocular ErgoTube ®
ErgoTube ® 45°
Binocular tube 45°
ErgoWedge®
Camera kit
M50 (Step)
ErgoWedge®
Video module
Filter slide housing
Video/photo tube
M60 (Zoom)
Video/photo tube
Light housing
M80 (Zoom)
Temperature range and cooling options The IntraCooler is an electrical cooling device with a closed-loop cooling system. The vaporized coolant is liquefied by means of compressors and heat exchangers. Three temperature ranges are available: Air cooling:
RT … 450 °C
IntraCooler (1 stage)
-35 … 450 °C
IntraCooler (2 stage)
-95 … 420 °C
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Efficiency Thanks to Practical Accessories Chip sensor box Since the chip sensors can only be used for one sample, it is a good idea to store them safely just in case you want to make more measurements afterward with the same sample. This avoids having to use a new sensor. Up to ten chip sensors with adhering sample material can be stored in the sensor box for experiments later on.
Standard accessories The following tools needed to prepare thin layers are supplied with the instrument as standard equipment: • knife with spare blades • lancet-shaped needle • tweezers • leather cloth • grinding stone • brush • hair holder • glass support and • indium for calibration
Microtome (optional accessory) The microtome can be used to cut 10 to 30 μm thick layers of a material, for example from small pieces of a polymer granule. The layers are then cut to small sample specimens for analysis using the knife supplied.
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Application Power
New Materials for the Future Flash DSC Has the Answers The Flash DSC 1 is the ideal addition for characterizing modern materials and optimizing production processes by thermal analysis.
Polymers, polymorphic substances, and many composites and blends have metastable structures that depend on the cooling conditions used in their production. On heating, reorganization processes such as the melting and recrystallization of unstable crystallites or the separation of phases may occur. The influence of reorganization on the heating curve can be analyzed by varying the heating rate.
Fast measurements save time in the analysis and development of materials. The quality of products can be improved through knowledge of structure formation at actual process cooling rates. The data can be used for simulation calculations and to optimize production conditions.
Flash DSC can simulate technical processes in which rapid cooling occurs. This yields information about the effect of additives (e.g. nucleating agents) under near-process conditions. Isothermal measurements provide information on the kinetics of transitions and reactions that take place in a few seconds.
Application Possibilities of Flash DSC • Detailed analysis of processes involving the formation of structure in materials • Direct measurement of rapid crystallization processes • Determination of the reaction kinetics of fast reactions • Investigation of the mechanism of action of additives under near-production conditions • Comprehensive thermal analysis of materials in very short time • Analysis of very small sample amounts • Determination of data for simulation calculations
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Melting of indium at different heating rates The melting of indium (1 μg) was measured at different heating rates between 0.05 K/s and 10 000 K/s. As in conventional DSC, the conduction of heat between the sensor and the sample (thermal lag) influences the measured onset temperature, Ton. Without correction, Ton increases linearly with the heating rate. The same is true for the Flash DSC 1. To accommodate the large heating rate range, the abscissa is displayed logarithmically in the diagram. For this reason, the linear function appears as a curve (blue).
Crystallization of isotactic polypropylene (iPP) on cooling In technical processes such as injection molding, the molding materials are cooled at several hundred K/s. To optimize their properties, it is important to have information about the crystallization behavior at these high rates. This information can be obtained from Flash DSC cooling experiments as shown in the upper diagram. The lower diagram displays the crystallization peak temperature of isotactic polypropylene (iPP) as a function of the cooling rate. The peak temperature shifts to lower temperatures at higher cooling rates. A conventional DSC 1 (red points) was used for cooling rates between 0.1 K/min and 60 K/min (0.0017 K/s and 1 K/s) and the Flash DSC 1 for rates between 0.5 K/s and 1 000 K/s. The peak temperatures agree with one another in the region where the cooling rates of the instruments overlap. Above 50 K/s, the formation of the mesophase is observed at about 30 °C in a second crystallization process (blue points). At cooling rates above 1 000 K/s, no crystallization occurs. The material remains amorphous with a glass transition at about -10 °C. The complete crystallization behavior is measured by the Flash DSC 1 in less than 30 min.
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Reorganization of amorphous iPP Amorphous isotactic polypropylene (iPP) is produced by cooling from the melt at 4 000 K/s. The material obtained was measured at heating rates between 5 K/s and 30 000 K/s. The glass transition occurs just below 0 °C followed by an exothermic peak due to cold crystallization. The crystallites melt above 100 °C. At higher heating rates, the cold crystallization peak is shifted to higher temperatures and melting peak to lower temperatures. From 1 000 K/s onward, the peak areas become significantly smaller until at 30 000 K/s reorganization no longer occurs in the sample.
Isothermal crystallization of iPP To measure the isothermal crystallization behavior of isotactic polypropylene (iPP), the melt was first cooled to different crystallization temperatures between 110 °C and -20 °C at 2 000 K/s. No formation of structure occurs under these conditions. Afterward, the crystallization process was measured isothermally. The exothermic crystallization peaks have their peak maximum at times between 0.05 s and 10 s. The reciprocal peak time is a measure of the crystallization rate and is displayed as a function of the crystallization temperature. The resulting curve exhibits a maximum at about 20 °C. At these low temperatures, crystallization takes place very rapidly. The crystallization process involves homogeneous nucleation. The measurement curves also show the change of crystallization kinetics with temperature.
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Nanofillers in PA The properties of polyamide 11 (PA 11) can be optimized through the addition of nanoparticles and the use of suitable processing conditions (e.g. for the injection molding of gearwheels). The effect of the fillers at the actual cooling rates influences the size of the crystallites and hence the mechanical properties. Three PA 11 samples with nanofiller contents of 0%, 2.5% and 5% were measured at different cooling rates in the Flash DSC 1 and in a conventional DSC 1. The enthalpy of crystallization at low cooling rates is constant up to 50 K/s, but becomes smaller at higher cooling rates. At 200 K/min, the sample no longer crystallizes. The influence of the cooling rate on the effect of the filler become clear when the peak temperatures are displayed as a function of the cooling rate. At cooling rates below 0.3 K/s (20 K/min), the unfilled PA 11 crystallizes first. At the technologically important high cooling rates, this changes and the nanoparticles accelerate crystallization.
Melting and decomposition of organic substances The determination of the melting behavior of organic substances is difficult if decomposition occurs in the melting range. At high heating rates, the decomposition reaction shifts to higher temperatures and separation of the two effects becomes possible. This is shown using saccharin as an example. At heating rates between 50 K/s and 100 K/s, melting and decomposition overlap. At higher heating rates, the two effects are separated.
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Flash DSC 1 Specifications Temperature data Temperature range
Air cooling
(Room temperature + 5 K) … 500 °C
IntraCooler (1-stage)
-35 °C … 450 °C
IntraCooler (2-stage)
-95 °C … 420 °C
Cooling rates (typical)
-6 K/min. (-0.1 K/s) … -240 000 K/min (-4 000 K/s)
Heating rates (typical)
30 K/min. (0.5 K/s) … 2 400 000 K/min (40 000 K/s)
Sensor data Sensor material
Ceramic
Thermocouples
16
Signal time constant, nitrogen
0.001 s
Sample size
10 ng … 1 µg
DSC Sensor Sensor type
Ultra-fast-sensor 1st generation
Pmax heat flow signal
20 mW
Noise heat flow signal
rms < 0.5 µW (typical)
Isothermal drift heat flow signal
< 5 µW/h (typical)
Baseline drift heat flow signal (empty sensor)
< 100 µW/h (typical)
Terminal Touch control
Color TFT, VGA 640 x 480 pixel
Signal generation Resolution
0.005 K (0 °C … 250 °C) 0.01 K (-100 °C … 400 °C)
Signal detection Sampling rate
Max. 10 kHz (10 000 points per second)
Resolution of temperature signal
2.5 mK
Noise temperature signal
rms < 0.01 K (typical)
Communication With personal computer (PC)
Ethernet
Dimensions Instrument dimensions (width x depth x height)
45 cm x 60 cm x 50 cm
Approvals IEC/EN61010-1:2001, IEC/EN61010-2-010:2003 CAN/CSA C22.2 No. 61010-1-04 UL Std No. 61010A-1 EN61326-1:2006 (class B) EN61326-1:2006 (industrial environments) FCC, Part 15, class A AS/NZS CISPR 22, AS/NZS 61000.4.3 Conformity mark: CE
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Subject to technical changes © 09/2010 Mettler-Toledo AG 51725315, Printed in Switzerland Marketing MatChar / MarCom Analytical
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