Preparation And Nonlinear Optical Properties Of Metal Phthalocyanine Based Polymers

Phthalocyanine compounds have a highly delocalized 18πelectron conjugated structure,which has broad application prospects as a third-order nonlinear optical material.However,its disadvantages such as easy aggregation and difficult dissolution have become the biggest obstacle to its nonlinear optical performance improvement and application in nonlinear optical devices.Based on this,two star metal phthalocyanine-based polymers were designed and synthesized in this paper,and the self-aggregation of phthalocyanine molecules was inhibited by the steric hindrance effect of the polymer chain.At the same time,the nonlinear optical properties of phthalocyanine are improved by introducing the atomic effect of heavy metals into phthalocyanine.The main research work is as follows:Two star-shaped compounds,2,9（10）,16（17）,23（24）-tetra（4-（2-dodecyltrithiocarbonate ethyl）phenoxy）phthalocyanine zinc（4HE-Zn Pc-DDMAT）and 2,9（10）,16（17）,23（24）-tetra（4-（2-dodecyltrithiocarbonate ethyl）phenoxy）phthalocyanine indium chloride（4BH-In Pc-DDMAT）,were designed and synthesized from the molecular point of view.Two kinds of four-arm star-shaped zinc phthalocyanine polymer Zn Pc-（PMMA）₄ and indium phthalocyanine polymer In Pc-（PMMA）₄ with zinc phthalocyanine and indium phthalocyanine as cores and polymethyl methacrylate（PMMA）as arms were synthesized by reversible addition-fragmentation polymerization（RAFT）method.The photophysical properties of the two polymers were investigated,and the nonlinear optical properties of the two polymers were investigated by Z-scan technique.The transparent optical plastics Zn Pc-（PMMA）₄/PMMA and In Pc-（PMMA）₄/PMMA with good optical uniformity were prepared by incorporating Zn Pc-（PMMA）₄and In Pc-（PMMA）₄ polymers into PMMA matrix,respectively.The third-order nonlinear absorption coefficient of Zn Pc-（PMMA）₄/PMMA is2.3×10^-9 m/W,the third-order polarization is 7.6×10^-11 esu,the initial threshold is 0.16 J/cm²,the minimum transmittance is 0.32,and the dynamic range is 0.49.The third-order nonlinear absorption coefficient of In Pc-（PMMA）₄/PMMA is 4.5×10^-9 m/W,the third-order magnetic susceptibility is 14.8×10^-11 esu,the initial threshold is 0.12 J/cm²,and the minimum transmittance is 0.12 J/cm².