Table 2.

The coefficients of thermal expansion (CTEs) of S-PU and H-PU.

	CTE (1/°C)
	1st Cycle		2nd Cycle
S-PU	0.484 a	0.132 b	0.398 a	0.306 b
H-PU	0.436		0.459

^a CTE at 40~79 °C. ^b CTE at 100~140 °C.