Summary Swelling properties and phase diagrams of binary systems composed of polyacrylate networks and a low molecular mass liquid crystal (LMWLC) have been investigated. The networks were prepared by ultraviolet (UV) irradiation of reactive mixtures including a monomer, a crosslinking agent and a photo‐initiator. Poly(n‐butylacrylate) networks were prepared using two crosslinking agents: 1,6‐hexanedioldiacrylate (HDDA) and a mesogenic acrylic acid 6‐(4'‐(6‐acryloyloxy‐hexyloxy)biphenyl‐4‐yl oxy) hexyl ester (AHBH). The obtained dry polyacrylates were characterized by differential scanning calorimetry, and immersed in an excess of a LMWLC solvent 4‐cyano‐4'‐pentylbiphenyl (5CB), forming polymer gels. A detailed study by polarized optical microscopy allowed to determine the swelling degree of the gels and to follow the phase behavior of the solvent inside the polymer matrix in a wide range of temperature. Swelling data were used to establish the phase diagrams in terms of composition and temperature. It was found that the poly(n‐butylacrylate) network obtained with the nematic crosslinking agent show fluctuations in the region of the nematic‐isotropic transition temperature of 5CB, probably due to the presence of nematic‐nematic coupling effects between the nematic solvent and the nematic moieties of AHBH.

The aim of this study is to examine and evaluate several dye/amine systems as photoinitiators for photopolymerization of 2-hydroxyethyl acrylate (HEA) monomer under visible light conditions. For this purpose, a series of dye/amine photoinitiators were formed using methylene blue (MB) or acridine orange (AO) as photosensitizers, and triethanolamine (TEOA), ethyl 4-(dimethylamino) benzoate (EDMAB), trioctylamine (TOA), and N,N-diméthylallylamine (DMAA) as co-initiators. The photopolymerization kinetic of the HEA monomer in the presence of proposed dye/amine systems was performed using Fourier-transform infrared spectroscopy (FTIR) analysis and the synergetic effect of the dye/amine photoinitiators systems on the photopolymerization efficiency was examined. Interestingly, (MB/EDMAB) system shows the better reactivity with a total conversion of HEA monomer.

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