Mechanism of Liquid Crystal Degradation

4-Octoxy-4 -cyanobiphenyl is one of the most commonly used liquid crystals in LCDs. According to the decomposition rate analysis, 4-octoxy-4 -cyanobiphenyl showed 

Radical inhibitors could inhibit the reaction process by consuming free radicals in the chemical reactions. Therefore, radical inhibitors could be used to evaluate the participation of free radicals in certain reactions. During the mechanism studies of organics oxidation, isopropanol was proposed to discern the role played by hydroxyl radical ( OH), because it is a well-known OH scavenger due to its high rate constant with the radical (1.9x10 L mol/s) [63,64], The reaction equation of isopropanol with OH can be depicted as follows  

According to Li et al. [65], hydrogen peroxide molecules can be split into hydroxyl radicals in absence of initiators (Eq. 17.1). The term M can be either a homogeneous or 

Besides the generation of OH, hydrogen peroxide also undergoes thermal decomposition which processed as Eq. (17.2) 

Decomposition of organic compounds with OH follows a hydrogen abstraction mechanism as shown in Eq. (17.3). 

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