Table 3. Representative Physical Properties of Various Insulating Polymeric Materials for Transparent Wearable Electronics.

	PET	PI	PEN	PC	PU	parylene	PDMS	ecoflex
Young’s modulus	1.57–5.20 GPa	0.107–46.9 GPa	5.00–5.50 GPa	1.79–3.24 GPa	0.00114–3.54 GPa	2.8–3.0 GPa	1.32–2.97 MPa	0.05–0.1 MPa
tensile strength (ultimate)	22.0–95.0 MPa	0.0480–345 MPa	200 MPa	28.0–75.0 MPa	0.138–65.0 MPa	48.3–68.9 GPa	6.7 MPa	0.37–1.7 MPa
elongation (yield) (%)	4.00–6.00	2.00–90.0		3.00–60.0		2.4–2.9
elongation (break) (%)	40.0–600	0.350–200	60	10.0–138	0.400–1300	10–250	135	800–900
refractive Index	1.575	1.68–1.78	1.7	1.58	1.5–1.7	1.59–1.66	1.4	1.4
transmittance	good	poor	good	good	good	good	good	poor
glass transition temperature (°C)	70.0–78.0	–20.0–385	120	141–150	–46.0–40.0	13–66	–120	–33
melting temperature (°C)	200–260	247–388	270	288–316	80.0	290–435	–40
specific heat capacity (J/g K)	1.00–1.50	0.920–1.13	2.59	1.17–1.70		0.711–0.837	1.38
thermal conductivity (W/m K)	0.190–0.290	0.0330–1.73	0.18	0.173–0.210	0.140–0.390	0.081–1.000	0.27