Online measurement technology
Online analytical technology concentrates on the generation of analytical data in real time, whereas the offline method only allows information to be analyzed about individual points in time of the reaction. As a result, it is possible to follow a polymerization with the best possible time resolution and immediately detect changes in the reaction variables. Thus, a more precise control and a better understanding of the reaction can be achieved. With the help of online analysis, the quality control and plant safety can be improved and the efficiency of the polyreaction can be optimized. Possible online analytical methods are ATR-IR spectroscopy, Raman spectroscopy and calorimetry.
Inline analytical investigation of the (co-)polymerisation of vinyl monomers
Whereas in the (co-)polymerization of vinylic monomers, the necessary residual monomer analysis is often carried out offline, i.e. downstream of the process, inline analysis offers the possibility of tapping the monomer-specific conversion directly in the chemical reactor. This not only results in a time advantage compared to offline analytical methods, which typically require a much more complex preparation effort, like HPLC or GC, but also offers the possibility of using read-out concentration data directly as a controlled variable for the dosing of monomer solution. From the data recorded over the entire polymerization period, it is easy to determine a turnover-time profile, which makes it possible to evaluate the polymerization performed much faster. Various reaction calorimeters are available as suitable analytical methods, such as an ATR-FT-IR spectrometer as well as a RAMAN spectrometer.