Thermal expansion of polytetrafluoroethylene (Teflon) from -190 to +300 C

The' linear t he rm a l ex pa nsion of fOlll samples of T eflo n was de termined . The' res ults for an neil. lecl T eflon m'e indi cated in a plot of t he ex pa nsion vel s us te m perature and in iI. table li st in g t he average coeffi cLCnts of lincar expa ns io n from -J 90 to + 300 C. The eff ect of internal r esidu al streRses on t he expans ion of T efto n was st udied a nd found to be consider able'. The fiT~t-orci er transit ions at 20 and 30 C are clearl y sh own in a plo t of t he coe ffi cients of rxpa nsLO n versus temperat ure.