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Title: Outgassing Studies of Foams for the W80 LEP (FY05)

Abstract

Removable epoxy foam (REF) is a novel material developed by researchers at Sandia National Laboratories to simplify the removal of encapsulants from electronic components [McElhanon, et al., Journal of Applied Polymer Science, 2002, 85, 1496-1502]. The material is based on a resin that includes a thermally reversible chemical bond. When the material is heated at relatively mild temperatures ({approx}50-90 C) in the presence of appropriate solvents, the reversible bonds are broken, and the material is easily rinsed away. In order to ease the removal of the encapsulant for surveillance purposes, it was proposed to use REF in the W80 LEP in place of the polyurethane TDI (toluene diisocyanate), which is being phased out at the Kansas City Plant due to toxicity concerns. Colleagues at Sandia noted that REF exhibited especially high outgassing of the liquid fluorinert, FC-72, which is used at a level of 5 wt% as the blowing agent in the foaming process. After obtaining a sample of the material from Sandia, headspace solid phase microextraction gas chromatography-mass spectrometry (SPME GC/MS) measurements were performed. These measurements revealed significant outgassing of fluorinert as well as other solvents and siloxanes [Memo, Vance, 3/3/05 & Vance, Foam PRT presentation UCRL-PRES-212462]. This reportmore » is intended to summarize foam outgassing studies performed at LLNL in support of the W80 LEP.« less

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
889995
Report Number(s):
UCRL-TR-217477
TRN: US200620%%196
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CHEMICAL BONDS; DEGASSING; KANSAS CITY PLANT; LAWRENCE LIVERMORE NATIONAL LABORATORY; POLYMERS; POLYURETHANES; REMOVAL; RESINS; SANDIA NATIONAL LABORATORIES; SILOXANES; SOLVENTS; SPECTROSCOPY; TOLUENE; TOXICITY

Citation Formats

Alviso, C, Harvey, C, and Vance, A. Outgassing Studies of Foams for the W80 LEP (FY05). United States: N. p., 2005. Web. doi:10.2172/889995.
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Alviso, C, Harvey, C, & Vance, A. Outgassing Studies of Foams for the W80 LEP (FY05). United States. doi:10.2172/889995.
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Alviso, C, Harvey, C, and Vance, A. Wed . "Outgassing Studies of Foams for the W80 LEP (FY05)". United States. doi:10.2172/889995. https://www.osti.gov/servlets/purl/889995.
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@article{osti_889995,
title = {Outgassing Studies of Foams for the W80 LEP (FY05)},
author = {Alviso, C and Harvey, C and Vance, A},
abstractNote = {Removable epoxy foam (REF) is a novel material developed by researchers at Sandia National Laboratories to simplify the removal of encapsulants from electronic components [McElhanon, et al., Journal of Applied Polymer Science, 2002, 85, 1496-1502]. The material is based on a resin that includes a thermally reversible chemical bond. When the material is heated at relatively mild temperatures ({approx}50-90 C) in the presence of appropriate solvents, the reversible bonds are broken, and the material is easily rinsed away. In order to ease the removal of the encapsulant for surveillance purposes, it was proposed to use REF in the W80 LEP in place of the polyurethane TDI (toluene diisocyanate), which is being phased out at the Kansas City Plant due to toxicity concerns. Colleagues at Sandia noted that REF exhibited especially high outgassing of the liquid fluorinert, FC-72, which is used at a level of 5 wt% as the blowing agent in the foaming process. After obtaining a sample of the material from Sandia, headspace solid phase microextraction gas chromatography-mass spectrometry (SPME GC/MS) measurements were performed. These measurements revealed significant outgassing of fluorinert as well as other solvents and siloxanes [Memo, Vance, 3/3/05 & Vance, Foam PRT presentation UCRL-PRES-212462]. This report is intended to summarize foam outgassing studies performed at LLNL in support of the W80 LEP.},
doi = {10.2172/889995},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Nov 23 00:00:00 EST 2005},
month = {Wed Nov 23 00:00:00 EST 2005}
}
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DOI:  10.2172/889995
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