A miscibility phase diagram of mixtures of UV-curable multifunctional thiolene-based optical adhesive (NOA65) and low molar mass 4-n-heptyl-4-cyanobiphenyl nematic liquid crystal (K21) has been established using light scattering, optical microscopy, and differential scanning calorimetry. The emergence of phase morphology was investigated during the heating and cooling cycles to identify various coexistence regions. A teapot phase diagram was obtained in which an upper critical solution temperature (UCST) overlapped with the nematic-isotropic transition of the liquid crystal. The phase diagram exhibited liquid + liquid, liquid + nematic, and pure nematic coexistence regions. Photopolymerization was carried out on various mixtures of NOA65 and K21 to fabricate polymer/liquid crystal composites by initiation in the one-phase and two-phase regions of the phase diagram. The rate constants for propagation and termination reactions (k p and kt) were determined as functions of temperature and conversion. On the basis of the observed kp and kt, the conversion rate was calculated by solving the rate equations for the photopolymerization process. It was found that the maximum conversion rate increased with increasing temperature and initial monomer concentration. The experimental results were in good accord with the calculated results in terms of both the order of magnitude and the trend. Of particular interest was that the domain morphology was uniformly distributed for the curing in the single phase, whereas the curing in the two-phase region resulted in nonuniformity of domain sizes.

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We investigate the conformation and relaxation dynamics of single DNA molecules in strong confinement (smaller than persistence length) with coarse-grained semiflexible chain (SFC) models using overdamped Langevin dynamics simulations. DNA properties in nanochannels and nanoslits are studied in confinement with height (H) ranging from the DNA radius of gyration (R g) to smaller than the persistence length (P). Qualitatively different dependences of chain conformation and relaxation time on H in moderate (P < H < R g) and strong (H < P) confinement are observed for very stiff SFC in the nanochannel but not in the nanoslit. The chain relaxation time (t relax) exhibits strong power-law dependence in H < P nanochannels, verified with and without including hydrodynamic interactions (HI). The inclusion of hydrodynamic interactions affects chain relaxation dynamics even in strong confinement, indicating the intersegmental hydrodynamic interactions affect dominant segmental relaxation mechanisms of strongly confined polymers.