Amphiphilic polymer conetworks (APCN) were prepared in N,N-dimethylformamide (DMF) by the interconnection of four-arm star poly(vinylidene fluoride) (PVDF, M n = 8800 Da) end-functionalized with benzaldehyde groups and four-arm star poly(ethylene glycol) (PEG, M n = 10 kDa) end-functionalized with benzaacylhydrazide groups. The PVDF stars were prepared via the reversible addition−fragmentation chain transfer polymerization of vinylidene fluoride using a tetraxanthate chain transfer agent. Equilibrium swelling of the APCNs in various solvents was dependent on the compatibility of the APCN components with the solvent, with the degrees of swelling (DS) varying from 22 in DMF (a good solvent for both PEG and PVDF), down to 8 in water (a good and selective solvent for PEG), and even down to 3 in diethyl ether (a nonsolvent for both polymers). Characterization of the conetworks in D 2 O using small-angle neutron scattering (SANS) indicated phase separation at the nanoscale, as evidenced by a (broad) correlation peak, consistent with a 19 nm spacing between the formed PVDF-based hydrophobic clusters of ∼10 nm diameter and an aggregation number of ca. 50 (growing in size with PVDF content). This behavior was independent of temperature from 25 to 70 °C and slightly dependent on deviations (±ca. 50 mol %) from the PVDF: PEG stoichiometry. Conetwork characterization in the bulk using atomic force microscopy (AFM) revealed a domain spacing of 14 ± 6 nm, in good agreement with the spacing of 11 nm calculated from the SANS results above (19 nm) but also taking into account the DS in D 2 O (5.5).Annealing the conetworks at 200 °C, a temperature above the melting point of PVDF, did not improve the morphological order in the AFM images. Finally, APCNs prepared in the room temperature ionic liquid binary mixture lithium bis(trifluoromethanesulfonyl)imide:1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (1:9 molar ratio) exhibited an electrochemical stability up to 4.3 V and a good room temperature ion conductivity of 0.6 mS cm −1 .

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International audienceWe present an extended structural study of globular complexes made by mixing a positively charge protein (lysozyme) and a negatively charged polyelectrolyte (PSS). We study the influence of all the parameters that may act on the structure of the complexes (charge densities and concentration of the species, partial hydrophobicity of the polyion chain, ionic strength). The structures on a 15 scale range lying from 10Å to 1000Å are measured by SANS. Whatever the conditions, the same structure is found, based on the formation of dense globules of ~ 100Å with a neutral core and a volume fraction of organic species (compacity) of ~ 0.3. At higher scale, the globules are arranged in fractal aggregates. Zetametry measurements show that globular complexes have a total positive charge when the charge ratio of species introduced in the mixture [-]/[+]intro > 1 and a total 20 negative charge when [-]/[+]intro < 1. This comes from the presence of charged species in slight excess in a layer at the surface of the globules. The globule finite size is determined by the Debye length k-1 whatever the way the physicochemical parameters are modified in the system, as long as chain-protein interactions are of simple electrostatics nature. The mean number of proteins per primary complex Nlyso_comp grows exponentially on a master curve with k-1. This enables to picture 25 the mechanisms of formation of the complexes. There is an initial stage of formation where the growth of the complexes is only driven by attractions between opposite species associated with counterion release. During the growth of the complexes, the globules progressively repell themselves by electrostatic repulsion because their charge increases. When this repulsion becomes dominent in the system, globules stop growing and behave like charged colloids: they aggregate 30 with a RLCA process, which leads to the formation of fractal aggregates of dimension Df 2.1

The apparatus for multioptional reflectometry (AMOR) at SINQ/PSI is a versatile reflectometer operational in the time-of-flight (TOF) mode (in a wavelength range of 0.15 nm < λ < 1.3 nm) as well as in the monochromatic (θ-2θ) mode with both polarized and unpolarized neutrons. AMOR is designed to perform reflectometry measurements in horizontal sample-plane geometry which allows studying both solid-liquid and liquid-liquid interfaces. A pulsed cold neutron beam from the end position of the neutron guide is produced by a dual-chopper system (side-by-side) having two windows at 180 • and rotatable with a maximum frequency of 200 Hz. In the TOF mode, the chopper frequency, width of the gating window and the chopper-detector distance can be selected independently providing a wide range of q-resolution (∆ q/q = 1-10%). Remanent FeCoV/Ti : N supermirrors are used as polarizer/analyzer with a polarization efficiency of ∼97%. For the monochromatic wavelength mode, a Ni/Ti multilayer is used as a monochromator, giving ∼50% reflectivity at a wavelength of 0.47 nm. In the present work, a detailed description of the instrument and setting-up of the polarization option is described. Results from some of the recent studies with polarized neutrons and measurements on liquid surfaces are presented.