Thermal tests differential scanning calorimetry

Supri and Ismail [46] prepared modified and unmodified low-density polyethylene (LDPE) and mixed it with water hyacinth fiber (WHF) composites by melt blending. Tensile test, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and water absorption behavior test of the composites were conducted. The NCO-polyol-modified LDPE/AAfHF showed higher tensile strength, modulus of elasticity, and water absorption resistance as compared to the unmodified LDPE/WHF composites. However, the elongation at break was better when the LDPE was immodi-fied. Moreover, the modified LDPE/WHF offered better thermal properties in comparison to the unmodified LDPE/WHF. The NCO-polyol was reported to create better dispersion of WHF in the LDPE matrix. 

ASTM E 1356-98, ASTM Book of Standards 2002. Standard Test Method for Assignment of the Glass Transition Temperature by Differential Scanning Calorimetry or Differential Thermal Analysis . ASTM International, Conshohocken, PA. 

These tests include differential scanning calorimetry (DSC) and various forms of differential thermal analysis (DTA) the insulated exotherm test (IET), decomposition pressure test (DPT), and the Carius (or ICI) sealed tube test. Commercial variants of these tests are available. 

Differential thermal analysis (DTA) is a technique in which the temperature difference between the sample tested and a reference material is measured while both are subjected to the controlled temperature program. Differential scanning calorimetry (DSC) is a technique in which the heat flow difference between the sample and reference material is monitored while both are subjected to the controlled temperature program. Thermogravimetric analysis (TGA) is a technique in which the weight of a sample is monitored during the controlled temperature program. 

We have synthesized two small scale batches (PA-DBX 1 and 2) of 2-3 g each and one intermediate scale batch (PA-DBX 3) of 8-10 g of DBX-1 from our NaNT. The procedure used to synthesize DBX-1 was based on literature methods.[5,6] For each batch, sensitivity tests, thermal stability by differential scanning calorimetry (DSC), and performance tests were performed and compared to the standard DBX-1 that was obtained from PSEMC (Pacific Scientific Energetic Materials Company, inventors of DBX-1). 

A thermochemical method that simultaneously measures differences in heat flow into a test substance and a reference substance (whose thermochemical properties are already well characterized) as both are subjected to programmed temperature ramping of the otherwise thermally isolated sample holder. The advantage of differential scanning calorimetry is a kinetic technique that allows one to record differences in heat absorption directly rather than measuring the total heat evolved/... 

Many different test methods can be used to study polymers and their physical changes with temperature. These studies are called thermal analysis. Two important types of thermal analysis are called differential scanning calorimetry (DSC) and differential thermal analysis (DTA). DSC is a technique in which heat flow away from a polymer is measured as a function of temperature or time. In DTA the temperature difference between a reference and a sample is measured as a function of temperature or time. A typical DTA curve easily shows both Tg and T . 

As regards thermal properties, the techniques of interest are differential thermal analysis (DTA) and its variant differential scanning calorimetry (DSC). In these techniques heat losses to the surrounding medium are allowed but assumed to be dependent on temperature only. The heat input and temperature rise for the material under test are compared with those for a standard material. In DTA, the two test pieces are heated simultaneously under the same conditions and the difference in temperature between the two is monitored, whereas in DSC the difference in heat input to maintain both test pieces at the same temperature is recorded. 

ASTM E1952, 2001. Standard test method for thermal conductivity and thermal diffusivity by modulated temperature differential scanning calorimetry. 

Of course, not all methods of cocrystal production require the use of auxiliary solvents. Thermal microscopy was used to determine if a particular carboxylic acid could cocrystallize with 2-[4-(4-chloro-2-fluorophe-noxy)phenyl]pyrimidine-4-carboxamide, with positive interactions being detected as crystalline material being produced at the binary interface [35]. Once identified, authentic cocrystal systems were prepared on a larger scale using solution-phase methods. In a similar study, hot-state microscopy was used to screen the possible interactions of nicotinamide with seven compounds of pharmaceutical interest that contained carboxylic acid groups [36]. A screening method for cocrystal formation based on differential scanning calorimetry has also been described, and used to demonstrate cocrystal formation in 16 out of 20 tested binary systems [37],... 

Sealed cell - differential scanning calorimetry (SC-DSC) test and sealed cell -differential thermal analysis (SC-DTA) test A2. Properties to be tested... 

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