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A silica-filled polydimethylsiloxane (PDMS) composite M9787 was investigated for potential outgassing in a vacuum/dry environment with the temperature programmed desorption/reaction method. The outgassing kinetics of 463 K vacuum heat-treated samples, vacuum heat-treated samples which were subsequently re-exposed to moisture, and untreated samples were extracted using the isoconversional and constrained iterative regression methods in a complementary fashion. Density functional theory (DFT) calculations of water interactions with a silica surface were also performed to provide insight into the structural motifs leading to the obtained kinetic parameters. Kinetic analysis/model revealed that no outgassing occurs from the vacuum heat-treated samples in subsequent vacuum/dry environment applications at room temperature (~300 K). The main effect of re-exposure of the vacuum heat-treated samples to a glove box condition (~30 ppm by volume of H2O) for even a couple of days was the formation, on the silica surface fillers, of ~60 ppm by weight of physisorbed and loosely bonded moisture, which subsequently outgasses at room temperature in a vacuum/dry environment in a time span of 10 yr. However, without any vacuum heat treatment and even after 1 h of vacuum pump down, about 300 ppm by weight of H2O would be released from the PDMS in the next few hours. Thereafter the outgassing rate slows down substantially. The presented methodology of using the isoconversional kinetic analysis results and some appropriate nature of the reaction as the constraints for more accurate iterative regression analysis/deconvolution of complex kinetic spectra, and of checking the so-obtained results with first principle calculations such as DFT can serve as a template for treating other complex physical/chemical processes as well. [ABSTRACT FROM AUTHOR]

Erratum: "The moisture outgassing kinetics of a silica reinforced polydimethylsiloxane" [J. Chem. Phys. (10)-(12) shows HT ht , where the correct expression should be HT ht . This typo (capital I T i should be used to represent temperature) has no impact on the results presented in the article. [Extracted from the article]

A combination of thermogravimetric analysis and temperature programmed decomposition was employed to identify the outgassing species, the total amount of outgassing, and the outgassing kinetics of high density polyethylene (HDPE) in a vacuum environment. The isoconversional kinetic analysis was then used to analyze the outgassing kinetics and to predict the long-term outgassing of HDPE in vacuum applications at ambient temperature. H2O and CnHx, with n as high as 9 and x centering around 2n, are the major outgassing species from solid HDPE, but the quantities evolved can be significantly reduced by vacuum baking at 368 K for a few hours prior to device assembly. [ABSTRACT FROM AUTHOR]

The isoconversional technique was employed for the measurement and prediction of H2O outgassing kinetics from silica-filled polydimethylsiloxane TR55 and S5370 in a vacuum or dry environment. Isoconversional analysis indicates that the energy barrier for H2O release from TR55 and S5370 is an increasing function of the fractional H2O release. This can be interpreted as the release of H2O from physisorbed water and then chemisorbed water with decreasing OH density from the surfaces of the embedded silica particles. Model-independent predictions of H2O outgassing based on the measured kinetics follow the trend of actual isothermal outgassing at elevated temperatures and suggest gradual outgassing in dry/vacuum storage over many decades at low temperatures for both TR55 and S5370. [ABSTRACT FROM AUTHOR]