高折射率钛-二苯醚-硅氧烷聚合物的合成表征和性能

Synthesis,Characterization and Properties of Titanium-Diphenylether-Siloxane Polymers with High Refractive Index

通过非水解溶胶-凝胶法合成了不同钛含量的乙烯基二苯醚硅氧烷低聚物(O0,O1,O3和O5),进一步与甲基苯基含氢硅油进行铂催化的硅氢加成交联反应,制得相应的聚合物(P0,P1,P3和P5)。通过傅里叶变换红外光谱和核磁共振氢谱对低聚物和聚合物进行了表征,并研究了钛元素对聚合物交联行为、热稳定性、折射率、光学透明性等的影响。与不含钛聚合物P0相比,钛-二苯醚-硅氧烷聚合物(P1,P3和P5)的折射率和热稳定性得到显著提高,后者具有高折射率(n=1.581~1.587)和优异的热稳定性(T5d>450℃@氮气,T5d>390℃@空气)。在热老化过程中,聚合物表现出优异的光学和热稳定性,具有高的光学透明度(90%@450 nm)和高的热稳定性(150℃热老化120 h后光学透明度为87%@450 nm),在LED封装胶中具有潜在的应用价值。

Vinyl-containing diphenylether-siloxane oligomers(O0,O1,O3,and O5)with different titanium contents were successfully synthesized with high yields by nonhydrolytic sol-gel reaction,and the obtained four oligomers were further crosslinked with methylphenyl hydro-silicone oil(4)to form corresponding polymers(P0,P1,P3,and P5)by hydrosilylation reaction.Their structures were characterized through spectroscopic characterization techniques including FT-IR and 1H-NMR spectroscopy.The effect of titanium element on the crosslinking behavior,thermal stability,refractive index,optical transparency,thermal aging stability,glass transition behavior and surface properties of the polymers were studied.Compared with titanium-free polymer P0,the thermal stability,refractive index,and thermal aging stability of titanium-diphenylether-siloxane polymers(P1,P3,and P5)were significantly improved.The titanium-diphenylether-siloxane polymers achieve a high refractive index(n=1.581~1.587)and thermal stability(T5 d,above 450℃in nitrogen and above 390℃in air).In thermal aging,the polymers exhibit superior performance with high optical transparency(~90%at 450 nm)and high thermal stability(~87%at 450 nm after thermal aging at 150℃for 120 h).These data indicate that the polymers have potential applications in LED encapsulants.