Poly(diallyldimethylammmonium chloride) samples were prepared in a wide range of molecular weight by radical polymerization at low degree of conversion to realize undisturbed molecular weight distributions. Determination of the molecular and thermodynamic parameters by viscometry, osmometry, light scattering, gel permeation chromatography (GPC) and analytical ultracentrifugation (AUC) give acceptable agreement. The high values of the second virial coefficient would result in a corresponding excluded volume. However, the dependencies of the radius of gyration and the second virial coefficient on molecular weight do not reflect the excluded volume effect. The discrepancy can be explained by a dominating Donnan contribution. Taking into account the polydispersities of the samples, a Kuhn segment length of 5 nm was determined for poly(diallyldimethylammonium chloride) in 0.5 M NaCl solutions. [η]‐M relations were obtained for 1 M NaNO3, 1 M NaCl and 0.5 M NaCl solutions.

Ionic liquids based on imidazolium, pyridinium, and alkylammonium salts were investigated as solvents in free radical polymerization of the model monomer n-butyl methacrylate. The properties of the ionic liquids were systematically varied by changing the length of the alkyl substituents on the cations, and by employing different anions such as tetrafluoroborate, hexafluorophosphate, tosylate, triflate, alkyl sulfates and dimethyl phosphate. Results were compared to analogous polymerizations in toluene and in bulk. The solvents have no detectable influence on polymer tacticity. However, the molar masses obtained and the degree of polymerization, respectively, are very sensitive to the choice of the solvent. The degrees of polymerization are significantly higher when polymerizations were carried out in ionic liquids compared to polymerization in toluene, and can even exceed the values obtained by bulk polymerization. Imidazolium salts unsubstituted at C-2 result in an increase in the degree of polymerization of the poly(butyl methacrylate) with increasing viscosity of these ionic liquids. Methyl substitution at C-2 of the imidazolium ion results in an increase in the viscosity of the ionic liquid and in a viscosity independent degree of polymerization of the poly(butyl methacrylate). Ionic liquids based on imidazolium salts seem preferable over pyridinium and alkylammonium salts because of the higher degree of polymerization of the poly(butyl methacrylate)s obtained in the imidazolium salts. The glass transition temperatures and thermal stabilities are higher for poly(butyl methacrylate)s synthesized in the ionic liquids compared to the polymer made in toluene.

A simple preparation method of ordered multilayer films of submicrometer- and micrometer-sized monodisperse latex particles in the broad range of 0.2−2.5 μm is reported. The films were prepared from aqueous suspensions by vertical deposition at elevated temperatures. Both hydrophobic polystyrene and hydrophilic core−shell particles allowed good array formation. Three-dimensional lattices were proved by transmission and reflectance vis−NIR−IR spectroscopy. Well-developed Bragg peaks up to 5000 nm have been registered. An observation of Fabry−Perot resonance signals in the spectra also confirms the good array quality. Optical properties of the gratings were investigated by laser diffraction and by diffraction using an optical microscope equipped with a Bertrand lens.

Ionically modified LCST polymers were synthesized by free radical copolymerization of N-isopropylacrylamide (NIPAM) with various cationic, anionic, and amphoteric comonomers, resulting in products with comparable molecular masses and charge concentrations. The temperature-dependent phase transition behavior of the copolymers was investigated in water, aqueous sodium chloride solutions, and mixtures of water with dimethylformamide (DMF) using light transmission measurements, static light scattering, viscometry, and sedimentation experiments in an analytical ultracentrifuge. The LCST of the cationic modified copolymers remains unchanged compared with the homopolymer, but it is increased as a result of an amphoteric or anionic modification. Phase transitions are accompanied by conformational changes followed by aggregation processes. These changes are enhanced in the presence of salt. The phase transition of poly-NIPAM-co-MADAMBQ ((methacryloyloxy)ethyl)dimethylbenzylammonium chloride) in 0.5 M NaCl was studied in detail investigating the temperature dependence of molecular parameters as intrinsic viscosity, particle mass, radius of gyration, second virial coefficient, and sedimentation coefficient.