Molded in pure or loaded PTFE
PTFE + fiberglass: Higher compressive strength, good chemical resistance, higher hardness, better wear resistance.
PTFE + carbon / graphite: Higher hardness, wear resistance, lower coefficient of friction, better thermal conductivity.
PTFE + graphite: Higher thermal conductivity, low coefficient of friction.
PTFE + bronze: Higher hardness, higher resistance to compression, wear and impact.