Outgassing characteristics of a polycarbonate core material for vacuum insulation panels

Abstract Performance deterioration with time is one of the most important issues in a vacuum insulation panel (VIP), which is mostly due to the inner gas pressure rise. Outgassing from the interior of core materials is the major gas source when the core material is a polymer. Outgassing characteristics of a polycarbonate as the VIP’s core material are examined theoretically and experimentally. To measure the outgassing rate, specific outgassing tests are carried out using a pressure rise method. Diffusive outgassing mechanism is discussed based on the Fick’s law. As the result, the total amount of dissolved gas and the diffusion coefficients of various gases in the polycarbonate are obtained by using the measured outgassing rate. Temperature dependence of the diffusion coefficient of nitrogen is also examined. It is shown that the outgassing rate of polymer core materials can be significantly reduced to a negligible level by a baking pre-treatment in vacuum and/or by a metal coating on the polymer surface.

[1]  V. Nemanic,et al.  Outgassing of a thin wall vacuum insulating panel , 1998 .

[2]  J. Fricke,et al.  Vacuum insulation panels—From research to market , 2008 .

[3]  John Crank,et al.  The Mathematics Of Diffusion , 1956 .

[4]  R. J. Elsey,et al.  Outgassing of vacuum materials-II , 1975 .

[5]  J. O’Hanlon.  A User's Guide to Vacuum Technology , 1980 .

[6]  J.J. Shea,et al.  Foundations of Vacuum Science and Technology , 1998, IEEE Electrical Insulation Magazine.

[7]  John Crank,et al.  Diffusion in polymers , 1968 .

[8]  P. Redhead.  Modeling the pump‐down of a reversibly adsorbed phase. II. Multilayer coverage , 1995 .

[9]  Jae-Sung Kwon,et al.  Vacuum maintenance in vacuum insulation panels exemplified with a staggered beam VIP , 2010 .

[10]  B. Dayton.  Relations Between Size of Vacuum Chamber, Outgassing Rate, and Required Pumping Speed , 2013 .

[11]  F. Shi,et al.  Outgassing of Rigid Open-celled Polyurethane Foam Used in Vacuum Insulation Panels Under Vacuum Condition , 2007 .

[12]  Bongtae Han,et al.  Ideal laminate theory for water transport analysis of metal-coated polymer films , 2008 .

[13]  J. C. Jaeger,et al.  Conduction of Heat in Solids , 1952 .

[14]  P. Redhead.  Modeling the pump‐down of a reversibly adsorbed phase. I. Monolayer and submonolayer initial coverage , 1995 .

[15]  Niels Jensen.  Vapor Pressure of Plastic Materials , 1956 .

[16]  K. J. Budde,et al.  Application of Ion Mobility Spectrometry to Semiconductor Technology: Outgassings of Advanced Polymers under Thermal Stress , 1995 .

[17]  G. Lewin,et al.  Reduction of stainless-steel outgassing in ultra-high vacuum , 1967 .

[18]  Js Kwon Jae-Sung Kwon,et al.  Effective thermal conductivity of various filling materials for vacuum insulation panels , 2009 .

[19]  A. Windle,et al.  Structure and oxygen-barrier properties of metallized polymer film , 1983 .

[20]  S. Chinn,et al.  Vacuum outgassing of high density polyethylene , 2008 .

[21]  Bojie Wang,et al.  Activation barriers for oxygen diffusion in polystyrene and polycarbonate glasses : effects of low molecular weight additives , 1994 .

[22]  S. Hwang,et al.  Permeation of oxygen, argon and nitrogen through polymer membranes , 1992 .