Fig. 5From: Gutta percha, natural rubber and balata-chemical characterization of polyisoprenes in the context of cultural heritageNOESY1D spectrum of trans-polyisoprene in CDCl3 obtained for the model pure commercial sample of trans-. This spectrum was used as a reference for the analysis of spectra from heritage material. Converted peaks show selective excitation (mixing time = 250 ms), and the arrows indicate nOesBack to article page