How does DSC identify crystallinity in polymers?
Polymer crystallinity can be determined with DSC by quantifying the heat associated with melting (fusion) of the polymer. This heat is reported as Percent Crystallinity by normalizing the observed heat of fusion to that of a 100 % crystalline sample of the same polymer.
What is DSC curve?
Differential Scanning Calorimetry (DSC) is a thermal analysis technique in which the heat flow into or out of a sample is measured as a function of temperature or time, while the sample is exposed to a controlled temperature program.
What thermal events of a semi crystalline polymer sample will be detected by DSC?
DSC is used widely for examining polymeric materials to determine their thermal transitions. Important thermal transitions include the glass transition temperature (Tg), crystallization temperature (Tc), and melting temperature (Tm).
What is DSC how is it useful in finding the properties of polymers?
DSC is a useful tool for thermal analyses of thermosetting plastics using changes in heat capacity results due to exothermic or endothermic reactions. DSC is also used to measure the Tg of thermoset polymers. The effect of hardeners on the thermal properties of cured materials can also be examined through DSC.
What is DSC in polymer?
Differential scanning calorimetry (DSC) is a technique used to investigate the response of polymers to heating. DSC can be used to study the melting of a crystalline polymer or the glass transition. The DSC set-up is composed of a measurement chamber and a computer.
What is the use of DSC analysis?
DSC is a thermal analysis apparatus measuring how physical properties of a sample change, along with temperature against time. In other words, the device is a thermal analysis instrument that determines the temperature and heat flow associated with material transitions as a function of time and temperature.
What is principle of DSC?
Principles of Differential Scanning Calorimetry (DSC) – the most used thermal analysis technique in pharmaceuticals. DSC is used to measure enthalpy changes due to changes in the physical and chemical properties of a material as a function of temperature or time.
How does DSC help in thermal analysis and materials Characterisation?
The most important effects that can be analyzed by DSC are melting point, melting range and melting behavior. DSC is also used to determine the heat of fusion, glass transition, and oxidation stability. TMA is normally used to study the expansion, softening or shrinkage of materials and the glass transition.
What are the factors affecting DSC curve?
Factors affecting DSC curve Instrumental factors: These include parameters such as – Furnace heating rate, furnace atmosphere, recording speed, geometry of sample holders, location of sensors, sensitivity of the recording system and material of the sample container.
How is DSc used to study the melting of polymers?
DSC can be used to study the melting of a crystalline polymer or the glass transition. The DSC set-up is composed of a measurement chamber and a computer. Two pans are heated in the measurement chamber. The sample pan contains the material being investigated. A second pan, which is typically empty, is used as a reference.
How is DSc used to determine upper use temperature?
Estimating upper use temperature from Tg or melting point One of the tools proven to address these needs is differential scanning calorimetry (DSC). This tool features many powerful techniques for studying polymer thermal properties and provides essential information to the polymer industry and end users of polymer-based products.
When to use quasi isothermal DSC for polymers?
After verification, the polymer samples of interest can be run using a series of temperatures within the verified performance range. Quasi-isothermal DSC (QiDSC) can also be used to monitor isothermal cure of thermosetting polymers, such as epoxy resins.
How is the crystallinity of a polymer determined?
DSC is a technique that measures heat flow into or out of a material as a function of time or temperature. Polymer crystallinity can be determined with DSC by quantifying the heat associated with melting (fusion) of the polymer.