This study examines the recycling of polytetrafluoroethylene (PTFE)/glass fiber (GF) printed circuit boards (PCB) laminates through mechanical grinding and the re-manufacture of new composites incorporating PTFE/GF recyclate using sintering processes with and without pressure (SWOP and SWP). The PTFE/GF recyclate was tested for mechanical and dielectric performance. Experimental data were fitted to modified Lichtenecker and Effective-Medium Theory (EMT) theoretical equations to estimate the dielectric constant of PTFE/GF recyclate subsheets for further use in new PTFE/GF laminates. It was found that the experimental values were inside of the Wiener bounds and fitted well the two theories for both manufacturing methods proposed. Overall, the results showed that PTFE/GF recyclate could be used as replacement for virgin PTFE/GF when incorporated in specific concentrations. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.