Table 1. Characteristic Bands of Characteristic Groups of NR and EU Gum.

Characteristic groups	Characteristic bands
	NR (Natural rubber)	EU gum (Eucommia rubber)
-C=C-	1645 cm−1	1645 cm−1
-CH3, -CH2-	1450 cm−1 , 1380 cm−1	1450 cm−1 , 1380 cm−1
-CH2-C(CH3)=CH-CH2-	835 cm−1	845 cm−1
Crystalline peaks		875 cm−1 , 798 cm−1 , 758 cm−1 , 595 cm−1 , 465 cm−1
Configuation	cis	trans