Isothermal titration calorimetry (ITC) was introduced as a highly sensitive tool to analyze interactions in polymer and material science by their thermodynamic patterns. The thermodynamic parameters ΔH, ΔS, ΔG, K B , and the stoichiometric ratio of the interactions in a complex organic-inorganic hybrid system were determined in a single experiment. In particular, the adsorption behavior of surface-active amphiphilic copolymers, bearing different types of anchor groups (nonionic, zwitterionic, and acidic), with SiO 2 nanoparticles in a multicomponent solvent system was investigated. The knowledge of the thermodynamic parameters of the interaction provided, beside its strength, a detailed understanding of its mechanism. Particularly, for the production of the nanocomposites, this knowledge might lead to a more rational and optimized design of these materials.

The use of multicomponent solvent systems and multiply functionalized emulsifiers opens a versatile avenue to high‐quality nanocomposites. Quantitative transfer of inorganic particles from an aqueous dispersion directly to hydrophobic solvent, where aggregation of the particles is fully suppressed, can be achieved on a large scale. Due to additional functionality on the surfaces, the particles can interact with a polymer matrix, allowing formation of homogeneous organic–inorganic hybrid materials.

Monocyclopentadienyl titanium imidazolin‐2‐iminato complexes [Cp′Ti(L)X2] 1a (Cp′ = cyclopentadienyl, L = 1,3‐di‐tert‐butylimidazolin‐2‐imide, X = Cl), 1b (X = CH3); 2 (Cp′ = cyclopentadienyl, L = 1,3‐diisopropylimidazolin‐2‐imide, X = Cl); 3 (Cp′ = tert‐butylcyclopentadienyl, L = 1,3‐di‐tert‐butylimidazolin‐2‐imide, X = Cl), upon activation with methylaluminoxane (MAO) were active for the polymerization of ethylene and propylene and the copolymerization of ethylene and 1‐hexene. Catalysts derived from imidazolin‐2‐iminato tropidinyl titanium complex 4 = [(Trop)Ti(L)Cl2] (Trop = tropidinyl, L = 1,3‐di‐tert‐butylimidazolin‐2‐imide) were much less active. Narrow polydispersities were observed for ethylene and propylene polymerization, but the copolymerization of ethylene/hexene led to bimodal molecular weight distributions. The productivity of catalysts derived from the dialkyl complex 1b activated with [Ph3C][B(C6F5)4] or B(C6F5)3 were less active for ethylene/hexene copolymerization but yielded ethylene/hexene copolymers of narrower molecular weight distributions than those derived from 1a/MAO. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6064–6070, 2008

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Summary: Two synthetic approaches to modify the surface of inorganic particles are presented. In the first approach the inorganic particles are prepared in-situ in a confined space in inverse emulsions. The used amphiphilic statistical copolymers act not only as emulsifiers, but they also hydrophobize the remaining inorganic particles after the precipitation. This approach represents a versatile method to obtain various inorganic nanoparticles as well as more complex inorganic materials like coremultiple shell and perovskite-based nanoparticles. The second procedure uses preformed inorganic particles, as an aqueous dispersion, to modify them with surface active amphiphilic copolymers in a multicomponent solvent system. This method turns out to be a simple but highly efficient method to modify preformed inorganic nanoparticles. The particles are characterized by SEM, TEM and dynamic light scattering. The modified inorganic nanoparticles are suitable to be homogenously incorporated into a polymer matrix to form transparent nanocomposite materials.