Synthesis and optical properties of σ–π conjugated aluminum-containing polyphenylcarbosilane (Al-PPCS) by hydrosilylation polymerization

Abstract Optical properties of aryl-substituted polyphenylcarbosilane (PPCS) and aluminum-containing polyphenylcarbosilane (Al-PPCS) prepared by hydrosilylation polymerization were studied. Polycarbosilane (PCS), aluminum-containing polycarbosilane (Al-PCS) and styrene were employed as reactants to yield σ–π conjugated PPCS and Al-PPCS using chloroplatinic acid as catalyst, respectively. Phenyl was directly attached to the conjugated main chains with Si C bonds. Effects of divinyl benzene cross-linking, oxidation curing and ultraviolet (UV) radiation on the photoluminescence (PL) properties of the samples were examined. PL spectra show strong blue light emission and the intensity of PCS is enhanced by adding the aryl groups and Al atoms. The excellent luminescent properties are attributed to the delocalization of electrons from the σ bond to π system. The hyperbranched Al-PPCS with extended σ–π conjugation has an obvious red-shifts PL, high quantum yield, excellent oxidation resistance and good UV resistance performance. Thermal analysis reveals that Al-PPCS can keep structure stability below 400 °C under an inert gas atmosphere. The Al-PPCS may have potential applications including organic electroluminescent (EL) devices.