Synthesis and characteristics of multi-aryl substituted molecular glasses bearing biphenyl core

Two novel compounds based on biphenyl structure, 2,2′-di(3,5-di(tert-butylcarbonate)phenyl)-4,4′-di(tert-butylcarbonate)biphenyl (A) and 2,2′,4,4′-tetra(3,5-di(tert-butylcarbonate)phenyl)biphenyl (B) were synthesized by commercially available materials. The products were fully characterized by FTIR, NMR and elemental analysis. The thermal stability and the phase transition of these compounds had been studied by TGA and DSC techniques. For compound A, thermal decomposition temperature was of 176 °C and glass transition temperature (Tg) was of 105 °C. While for compound B, the thermal decomposition occurred at 186 °C and Tg was of 122 °C. The synthesized compounds were found to be amorphous materials by XRD analysis and good film-forming ability by AFM analysis. These results indicated that the synthetic molecular glasses would be suitable for low molecular weight photo resists in EUV lithography.

► Two multi-aryl substituted compounds bearing biphenyl core were synthesized and characterized.
► These compound showed thermal stability and moderate Tg.
► XRD analyses indicated these compounds were amorphous.
► AFM images presented the good film-forming ability.