Swelling behavior of poly(n‐butyl acrylate/1,6‐hexane‐diol‐di‐acrylate)/nematic liquid crystal E7 systems: Experimental measurements and modeling by factorial design method

The swelling process of poly(n‐butyl acrylate/1,6‐hexane‐diol‐di‐acrylate) Poly(Abu/HDDA)] networks, immersed in a liquid crystalline (LC) solvent, was investigated in order to obtain improved swelling ratio values upon application of an original method using a central composite design. The polymer/LC systems under investigation were elaborated via a photopolymerization/crosslinking phase separation process induced by UV radiation of initial mixtures composed of mono‐ and bifunctional monomers, a photoinitiator, and the low‐molar‐weight nematic LC blend E7. The parameters which strongly impact the swelling behavior of Poly(Abu/HDDA)/E7 systems were identified as temperature and concentration of the bifunctional monomer in the initial photopolymerizable mixture, thus controlling the crosslinking density of the final polymer network. The existence of interactions and synergies between these two parameters were also examined. The quality of the model was verified by a good agreement between experimental results and predicted response. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45230.