Transparent and flexible photocatalytic film comprising organophosphonate-modified polysilsesquioxane-anchored titanium dioxide: hydroxy group ratio and organic substituent on phosphorous atoms

• Published in: Polymer journal Vol. 55; no. 9; pp. 975 - 982
• Main Authors: Kajiyama, Miyu, Sato, Yohei, Okada, Takumi, Motomura, Haruka, Ando, Shiro, Suzuki, Tomonori, Yamamoto, Kazuki, Hayami, Ryohei, Gunji, Takahiro
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.09.2023; Nature Publishing Group
• Subjects: 639/301/923/1028; 639/638/455; 704/172/169; Biomaterials; Bioorganic Chemistry; Bisphenol A; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Cracks; E coli; Epichlorohydrin; Hydroxyl radicals; Methylene blue; Original Article; Phenyl phosphonate; Phosphonates; Photocatalysis; Photodegradation; Polymer Sciences; Polysilsesquioxanes; Surfaces and Interfaces; Thin Films; Titanium; Titanium dioxide; Titanium oxides
• ISSN: 0032-3896; 1349-0540
• DOI: 10.1038/s41428-023-00796-3

Transparent and flexible photocatalytic films have attracted considerable attention in recent years. We previously prepared a film with titanium dioxide (TiO 2 ) and an anchor layer of phenylphosphonate-modified polysilsesquioxane (PhPPS-low), which had a phosphonate group and a phenyl substituent; this film exhibited transparency and flexibility. In this study, we reported the differences in the hydroxy group ratio on the phosphorous atoms and the presence or absence of phenylene moieties. Three organophosphonate-modified polysilsesquioxanes (APPS-low, APPS-high, and PhPPS-high) were synthesized. All photocatalytic films using APPS-high, APPS-low, and PhPPS-high exhibited photodegradation of methylene blue and photocatalytic bactericidal effects on Escherichia coli , and hydroxyl radical generation was confirmed. In particular, the photocatalytic film with PhPPS-high showed the highest photocatalytic ability. The transparent and flexible photocatalytic films composed of titanium oxide, organophosphonate-modified polysilsesquioxane, and poly(bisphenol A- co -epichlorohydrin) were prepared. The effects of hydroxy group ratio and organic substituent on phosphorus atoms in these films were evaluated by appearance and photocatalytic ability. Film using anchoring layer with APPS-low was formed large cracks, while films with other anchoring layers were formed no cracks. However, all films were formed small cracks after a 10-day durability test. All films showed photodegradation ability of methylene blue, photoinduced hydrophilicity, and photocatalytic bactericidal effects on Escherichia coli .