TekNational, Inc.
Tek-Sil® GP8X Series
If you need a non-silicone gap filler, Tek-Sil® GP8X is a highly conformable, thermally conductive, non-flammable acrylate resin (non-silicone) sheet with thermally conductive fillers.  This material is presently available in four thicknesses. 
GP8X SeriesUnitGP8X-40GP8X-60GP8X-98GP8X-118
Thicknessmm1.0 +/-0.31.5 +/-0.32.5 +/-0.33.0 +/-0.3
Thermal Resistance°Cin²/W1.021.241.752.25
ColorvisualLight Gray
Thermal Conductivitywatt/m-k1.5
Volume ResistivityMohm·m
Withstand VoltagekV/mm·AC11
Specific Gravitygr/cm³2x103
HardnessShore OO53
Continuous Use°C-40° to +105°
Flame RetardanceUL 94V V-0