Table 3. Comparison of High Performance Insulating Polymer Characteristics for Automotive Wiring

Material	Temperature class rating	Mechanical strength	Flexibility	Chemical resistance	Cost	Characteristics
XLPE XLPO	125 or 150°C	good	general	general	middle	excellent balance of heat resistance, mechanical strength, and cost. most widely used.
SiR	175~200°C	general	very good	good	expensive	maintains excellent flexibility over a wide temperature range. low mechanical strength.
FEP	200°C	good	good	very good	very expensive	excellent heat resistance and chemical resistance, excellent electrical properties. very expensive.
PFA	260°C	good	good	very good	very expensive	excellent heat resistance and chemical resistance, excellent electrical properties. very expensive.
PEEK	250 or 260°C	very good	general	very good	very expensive	excellent thermal resistance and chemical resistance, excellent electrical properties. very expensive.
PI	> 260°C	very good	general	good	very expensive	extreme heat resistance. may be susceptible to moisture and mechanical stress.