Composite materials process monitoring

HPLC is extremely useful in monitoring and optimizing industrial processes. Conventional process monitors measure only bulk properties, such as the temperature and pressure of a reactor, while HPLC permits continuous realtime monitoring of consumption of starting materials, product composition, and impurity profile. There are a number of new initiatives relevant to HPLC for process monitoring, including sample preparation, automation, miniaturization, and specialized detectors. 

A miniaturized MB spectrometer MIMOS II was developed for the robotic exploration of Mars, where it provided fundamental information about mineralogical composition and alteration processes, helped to classify rocks and soils, aided geologic mapping, was instrumental in assessing habitability of past and present environments, and identified potential construction resources for future human explorers. The applicability of the instrument as a process monitor for oxygen production and prospecting tool for lunar ISRU has been demonstrated. The characterization of air pollution sources and the study of mixed-valence materials as a function of depth in soil are examples of terrestrial in situ applications. MIMOS lla with additional XRF capability will open up new applications. 

Bar-Dohen, K.H. Nguyen, and R. Botsco Eddy Currents Monitor Composites Cure. Advanced Materials Processes, 41 (April 1991). 

A number of composition analyzers used for process monitoring and control require chemical conversion of one or more sample components preceding quantitative measurement. These reactions include formation of suspended solids for turbidimetric measurement, formation of colored materials for colorimetric detection, selective oxidation or reduction for electrochemical measurement, and formation of electrolytes for measurement by electrical conductance. Some nonvolatile materials may be separated and measured by gas chromatography after conversion to volatile derivatives. 

Wolf, C. J. and Fanter, D. L., The Use of Chemiluminescence to Monitor the Aging Processes in Polymers and Composites, in Proceedings of the Critical vlew Techniques for the Characterization of Composite Materials (Army Materials and Mechanics Research Center, 1982), p. 311. 

Development and application of composites containing nanostructured forms of metals open new horizons in creation of novel composite materials with controlled-quality properties and their usage in various kinds of human activity medicine, nanophotonics, catalytic chemical and refining processes, membrane technology, ecology, climate-monitoring systems, pure energetic, etc. 

Summerscales J. In-process monitoring for control of closed-mold techniques for the manufacture of thermosetting matrix composites. In Shonaike GO, Advani SG, editors. Advanced Polymeric Materials Structure-Property Relationships. Boca Raton, FL CRC Press 2003. p 57 ff. 

Partridge IK, Maistros GM. Dielectric cure monitoring for process control. Comprehensive composite materials, vol. 5 2000. p. 413—426. 

Control of 26 setting for peak and background measurements Control of PHS window setting Selection of amplifier and proportional counter gain Process control feedback Product quality monitoring Defective product composition alarm Process adjustment recommendations Incoming materials inspection Closed-loop process control... 

---