Bubble-Point Measurements and Modeling of Binary Mixtures of Linear Siloxanes
Luuc Keulen, Elisabeth Mansfield, Ian H. Bell, Andrea Spinelli, A. Guardone
The bubble-point pressures of three binary mixtures of linear siloxanes have been mea4 sured. The binary mixtures consist of hexamethyldisiloxane (MM) which is mixed with ei5 ther octamethyltrisiloxane (MDM), decamethyltetrasiloxane (MD2M), and dodecamethylpen6 tasiloxane (MD3M). For each mixture, three compositions were measured where MM was present in approximately 25 mol%, 50 mol%, and 75 mol%. The bubble-point pressures were measured over a temperature range of 270 K to 380 K for all mixtures. Large uncertainties are observed for the lower temperatures (below 320 K) due to non-condensable impurities. A detailed analysis is performed to determine the effect of non-condensable gases on the measured bubble-point pressure data. The newly obtained bubble-point pressure data is used to determine new binary interaction parameters for the multicomponent Helmholtz energy model. The data is used for the fitting of the binary interaction parameters is weighted by the relative uncertainty,this ensures that data points with high uncertainty contribute less to the final binary interaction parameter. In this work, a description of the experimental apparatus and measurement procedure is given, as well as the measured bubble-point pressure data and newly obtained binary interaction parameters.
, Mansfield, E.
, Bell, I.
, Spinelli, A.
and Guardone, A.
Bubble-Point Measurements and Modeling of Binary Mixtures of Linear Siloxanes, Journal of Chemical and Engineering Data, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=924943
(Accessed April 22, 2021)