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Calorimetry cure enthalpy measurements using

Cure kinetics of thermosets are usually deterrnined by dsc (63,64). However, for phenohc resins, the information is limited to the early stages of the cure because of the volatiles associated with the process. For pressurized dsc ceUs, the upper limit on temperature is ca 170°C. Differential scanning calorimetry is also used to measure the kinetics and reaction enthalpies of hquid resins in coatings, adhesives, laminations, and foam. Software packages that interpret dsc scans in terms of the cure kinetics are supphed by instmment manufacturers. [Pg.301]

Differential Scanning Calorimetry (DSC) This is by far the widest utilized technique to obtain the degree and reaction rate of cure as well as the specific heat of thermosetting resins. It is based on the measurement of the differential voltage (converted into heat flow) necessary to obtain the thermal equilibrium between a sample (resin) and an inert reference, both placed into a calorimeter [143,144], As a result, a thermogram, as shown in Figure 2.7, is obtained [145]. In this curve, the area under the whole curve represents the total heat of reaction, AHR, and the shadowed area represents the enthalpy at a specific time. From Equations 2.5 and 2.6, the degree and rate of cure can be calculated. The DSC can operate under isothermal or non-isothermal conditions [146]. In the former mode, two different methods can be used [1] ... [Pg.85]

Differential scanning calorimetry was used to measure both the extent of cure as well as the progress of enthalpy recovery in the neat epoxy resin. A Perkin Elmer DSC-2 differential scanning calorimeter equipped with a scannlng-auto-zero unit for baseline optimization was utilized to measure the heat capacity of the... [Pg.128]


See other pages where Calorimetry cure enthalpy measurements using is mentioned: [Pg.199]    [Pg.83]    [Pg.583]    [Pg.61]    [Pg.163]   
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