Fluorinated compound, photopolymerizable composition, hologram recording medium, preparation method thereof and optical element comprising the same

A fluorinated compound represented by the following Chemical Formula 1:

• wherein, in the Chemical Formula 1,
• Z1 and Z2 are each independently —O—, —S—, or —NH—,
• at least one of R1 to R4 is a fluorine-containing substituent, which is an alkyl group having 1 to 20 carbon atoms substituted with 2 or more fluorines, a cycloalkyl group having 3 to 30 carbon atoms substituted with 2 or more fluorines, or an aryl group having 6 to 30 carbon atoms substituted with 2 or more fluorines,
• when R1 to R4 are not fluorine-containing substituents, R1 to R4 are each independently an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, a heterocycloalkyl group having 4 to 30 carbon atoms, a cycloalkylalkyl group having 7 to 40 carbon atoms, an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 4 to 30 carbon atoms or an arylalkyl group having 7 to 40 carbon atoms, or a substituent in which at least one —CH2— of the above substituents is substituted with —O—, —S— or —NH—.