XPS and SSIMS analysis of the surface chemical structure of poly(caprolactone) and poly(β-hydroxybutyrate-β-hydroxyvalerate) copolymers

Abstract The surface chemical structures of poly(β-hydroxybutyrate), poly(caprolactone) and poly(β-hydroxy-butyrate-co-β-hydroxyvalerate) have been analysed using static secondary ion mass spectrometry and X-ray photoelectron spectroscopy. The X-ray photoelectron spectroscopy data confirm the purity of the polyester surfaces and there is close agreement between the stoichiometric and experimentally determined ratios of the peaks and different carbon environments within the C1s envelopes. The static secondary ion mass spectrometry analysis reveals general fragmentation pathways which permit the ready distinction between the different polyesters examined. The differentiation of the different monomer repeat units in the copolymer together with the detection of some ions representative of the random copolymer sequence are also possible in the static secondary ion mass spectrometry analysis.