LAUSR

Abstract Luminescent platinum(II) small molecules have aroused much attention due to their unique Pt(II)–Pt(II) interaction and intriguing luminescence properties; while incorporation of Pt(II) centers into polymers is still in its infancy. In this work, a class of random copolymers ((M1)x-co-(MPt)y; x = 200, y = 1, 2, 4) was synthesized by copolymerization of a newly designed norbornene-functionalized platinum(II) complex MPt and oligoethylene glycol modified monomer M1 using ROMP method. Compared to monomer MPt, the resulting polymers exhibit enhanced Pt(II)–Pt(II) interaction and intense low-energy emissions because of the confinement effect. Moreover, the photophysical properties of MPt and polymers ((M1)x-co-(MPt)y; x = 200, y = 1, 2, 4) were found to be highly dependent on the solvents and platinum(II) content in the polymers. Through switching on and off of the Pt(II)–Pt(II) interaction, (M1)200-co-(MPt)4 has been successfully demonstrated to be a self-referenced luminescent thermometer, which showed 2.11% K−1 (in TCE, 278K) relative temperature sensitivity, excellent reversibility and repeatability.