Synthesis and optical properties of organic-inorganic hybrid
semi-interpenetrating polymer network gels containing polyfluorenes
Naofumi Naga, Tomoharu Miyanaga, Hidemitsu Furukawa
Supporting Information
SMILS was recently developed for the detailed characterization of network structure in
polymer gels. In general, conventional light scattering systems is hardly used to
quantitatively characterize the network structure in polymer gels since the static
inhomogeneities that are inevitably memorized in the network. The inhomogeneities
sometimes cause undesired large interference, which prevents the exact characterization.
The developed SMILS system enables us to scan and measure at many different
positions in an inhomogeneous gel, in order to rigorously determine a time- and
space-averaged, i.e. ensemble-averaged, (auto-)correlation function of fluctuating mesh
size in the gel. Analysis of the ensemble-averaged function makes it possible to
quantitatively characterize the mesh-size distribution of network structure in
inhomogeneous gels. Scanning measurement was performed at more than 25 points for
each sample to determine ensemble-averaged dynamic structure factor. The determined
correlation function was transformed to the distribution function of relaxation time by
using numerical inversed Laplace transform calculation. For these gels, a few peaks of
relaxation modes were observed in the distribution function. Based on the observation
of scattering-angle, q, dependence of the relaxation modes, all the observed modes
usually have q2-dependence, which correspond to translational diffusion. In the
following, all the results were determined at the scattering angle fixed at 90 ˚. The
observed modes, as assigned to the cooperative diffusion of gel network, were used for
the determination of radius of mesh (mesh size) (; m) with Einstein-Stokes formula.
16n 2 R K B sin 2
where n, R, KB, , , and  are refractive index of toluene, Ensemble-averaged
relaxation time (s), Boltzmann constant (1.38 × 10-23 JK-1), scattering angle (90º),
viscosity coefficient of toluene (5.22 ×10-4 N m2 s-1) or cyclohexane (8.21 ×10-4 N m2
s-1) at 298 K, wave length of incident ray (6.328×10-7 m), respectively.
Figure S1. Photographs of TMCTS-HD semi-IPN gels containing PF6L in cyclohexane,
monomer concentaration: (a) 4.9 wt%, (b) 9.9 wt%, fluorene unit of PF6L = 1.0 mM.
Absorbance (a.u.)
438 nm
Wavelength (nm)
Figure S2. UV-vis spectrum of the POSS-DD semi-IPN gel containing PF8, monomer
concentration: 9.9 wt%, fluorene unit of PF8 = 1.0 mM, excitation wavelength = 380