Surface oxidation of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) via photo-activated chlorine dioxide radical

•New strategy for efficient surface modification of PHBH using UV-activated ClO2•.•This modification could improve the PHBH adhesion property with metal.•The dyeability of the PHBH fibrous membrane was achieved via this modification. As one of the polyhydroxyalkanoates (PHA), which are biodegradable and available in nature, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is a good alternative to deal with the environmental problems caused by traditional plastics. However, only some studies have investigated the surface modification of PHBH to expand its applications. In this study, surface modification of the PHBH film/fibrous membrane was achieved via oxidation using the light-activated chlorine dioxide radical (ClO2•) gas. After surface oxidation, the ratio of the oxygen-containing functional groups on the PHBH film surface increased and the improvement in surface hydrophilicity was confirmed. In addition, the effects of the ratio of 3-hydroxyhexanoate in PHBH and the oxidation time were investigated. Surface modification via oxidation improved the adhesion property of the metal layer plated on the PHBH film surface and the dyeability of the PHBH fibrous membranes using cationic dyes. Therefore, this clean and effective oxidation method is a potential surface modification methodology that can broaden the practical applicability of the PHBH materials.