By Xenocs
The working principle and output of the two techniques are very different. DSC is a thermal method which measures the heat flow in a sample as it is subjected to controlled temperature changes. This enables the determination of the material’s thermal properties including its melting point, glass transition temperature or heat capacity. Understanding the material’s response to changes in temperature is crucial for the development of efficient manufacturing and processing methods. However, DSC alone does not provide information about the structure of a material. To couple the phase-transition thermodynamics, as determined through DSC, with morphological changes, structural methods such as SAXS need to be employed. By measuring the scattering pattern of X-rays after they have passed through a sample, SAXS can provide the size, shape and spatial arrangement of nanoscale structures in a material. Moreover, when analyzing samples consisting of different phases, such as different polymorphic forms, crystalline and amorphous regions, or multiple components, it can be challenging to quantify the individual contributions of each one using DSC alone. DSC measures the overall heat flow associated with phase transitions, which in this case will typically result in broad thermal signals. but it cannot directly distinguish between different phases and their contributions. On the other hand, SAXS/WAXS measurements can be used to quantify a sample composed of different phases and provide detailed structural information about each phase. This information can then be utilized to better interpret and decompose the broad phase transitions observed in DSC measurements, allowing for a more comprehensive analysis of the phase transitions and their components. In addition, DSC is unable to detect the anisotropy of observed crystalline phases, which is considered to be the driving mechanism underlying reinforced properties e.g., polymer fiber technology [1-3]. Furthermore, both techniques find applications in a wide range of fields such as: 1. Investigating the structure and thermal behavior of polymers, 2. Studying the thermal stability of proteins [4], 3. Characterizing the morphology of nanoparticles, 4. Understanding the behavior of lipids [5] In the case of SAXS measurements, using the one-dimensional correlation function enables accurate and reliable determination of both the long period and thickness of lamellar crystals. Types of samples: gel, solid, powder, liquid, turbid Sample preparation: Minimal Observation volume: 0.1 to 1 mm³ Range: < 1 - 350 nm (up to 2.5 µm [PP1] USAXS) In-situ or operando: Yes Measuring time: Fast Statistics: Statistically relevant results Spatial Resolution: Low Data: Scattering pattern in reciprocal space Beam damage: No Limitations: Requires sufficient electron density contrast Information: Size, shape, crystallinity, orientation, bulk and surface nanostructures, correlation function, crystalline and nanostructure phases identification
