An efficient grafting‐onto way to polyoctenamer‐ graft ‐polyethylene glycol brushes is proposed, based on the combination of ring‐opening metathesis polymerization and polymer‐analogous reaction. New monomers cyclooct‐4‐en‐1‐ylmethyl methanesulfonate and cyclooct‐4‐en‐1‐ylmethyl 4‐methylbenzenesulfonate are synthesized from cyclooctadiene and then polymerized with high yields on first generation Grubbs’ catalyst. Mesylate and tosylate pendants in the resulting polymers are readily substituted with oligoethylene glycol monomethyl ethers in the presence of potassium tert‐butoxide. Complete functionalization is achieved in the case of mPEG 356 and mPEG 750 , thus yielding polymer brushes with the number‐average molar mass of ≈200 kg mol −1 , which are soluble in water, ethyl acetate, tetrahydrofuran, and chloroform. As proof of the concept, polynorbornene‐ graft ‐polyethylene glycol brush is synthesized by the same method, thus demonstrating universality of the proposed approach.

Solution properties of amphiphilic polyoctenamers functionalized with short polyethylene glycol side chains in the 3(rd) and 5(th) positions are compared using light scattering and diffusion-ordered spectroscopy. To that end, 3- and 5- succinyl cyclooctenes are synthesized in several steps, starting from cyclooctene and 1,5-cyclooctadiene, respectively, then grafted with oligoethylene glycol methyl ether, and involved as monomers in ring-opening metathesis polymerization on the second-generation Grubbs catalyst. In the case of 3-succinyl cyclooctene, the polymerization proceeds in a regio- and stereoselective manner to afford macromolecules with full head-to-tail regioregularity and trans-stereoregularity. Although both 3- and 5-functionalized polyoctenamers form micelles in water and chloroform above certain concentrations and exhibit a cloud point on heating, it is found that regularly positioned pendants lower the tendency to aggregation more efficiently, which can be important for all applications involving the use of amphiphilic polymer brushes.

New amphiphilic polyoctenamers containing ethylene glycol-based substituents at the 5th position were synthesized and characterized.

For the first time, the interaction of polyvinyl alcohol and a copolymer of sodium salts of styrenesulfonic and maleic acids in aqueous solutions has been studied using the techniques of static and dynamic light scattering and capillary viscometry. It has been shown that hydrogen-bonded complexes are formed between them, with compaction of polyvinyl alcohol coils occurring in dilute solutions and additional structuring of the solution in semidilute solutions. The activation parameters (enthalpy and entropy) of viscous flow have been assessed, confirming the formation of the complexes. The concentration regimes of solutions of polyvinyl alcohol, the copolymer, and the complexes have been studied. It has been shown that the semidilute entanglement-free regime disappears in solutions of the complexes.

Controlled radical polymerization of lauryl methacrylate in polyalphaolefin base oil has been performed for the first time in the presence of 2-cyano-2-propyl dodecyl trithiocarbonate. It has been shown that polymerization proceeds to high monomer conversions and leads to the formation of a polymer with a narrow molecular weight distribution. At the same time, the reaction mixtures retain their transparency after polymerization is completed. The synthesized polymers have a thickening ability, which naturally increases with an increase in their number-average molecular weight.

Fluorinated polymers are attractive due to their special thermal, surface, gas separation, and other properties. In this study, new diblock, multiblock, and random copolymers of cyclooctene with two fluorinated norbornenes, 5-perfluorobutyl-2-norbornene and N-pentafluorophenyl-exo-endo-norbornene-5,6-dicarboximide, are synthesized by ring-opening metathesis copolymerization and macromolecular cross-metathesis in the presence of the first- to third-generation Grubbs’ Ru-catalysts. Their thermal, surface, bulk, and solution characteristics are investigated and compared using differential scanning calorimetry, water contact angle measurements, gas permeation, and light scattering, respectively. It is demonstrated that they are correlated with the chain structure of the copolymers. The properties of multiblock copolymers are generally closer to those of diblock copolymers than of random ones, which can be explained by the presence of long blocks capable of self-organization. In particular, diblock and multiblock fluorine-imide-containing copolymers show a tendency to form micelles in chloroform solutions well below the overlap concentration. The results obtained may be of interest to a wide range of researchers involved in the design of functional copolymers.

Biocidal coatings have been used in biomedicine, cosmetology and the food industry. In this article, the coatings are described as being composed of non-stoichiometric polycomplexes, products of electrostatic coupling of two commercial biodegradable ionic polymers, anionic sodium alginate and cationic quaternized hydroxyethyl cellulose ethoxylate. Non-stoichiometric polycomplexes with a 5-fold excess of the cationic polymer were used for immobilizing hydrophobic biocidal 4-hexylresorcinol (HR). Being dispersed in water, the polycomplex particles were capable of absorbing a tenfold excess of HR in relation to the polycation. After deposition onto the plastic surface and drying, the aqueous polycomplex–HR composite formulation forms a transparent homogeneous coating, which swells slightly in water. The interpolyelectrolyte complex (IPEC) is substantially non-toxic. The incorporation of HR in the IPEC imparts antimicrobial activity to the resulting composite, in both aqueous solutions and coatings, against Gram-negative and Gram-positive bacteria and yeast. The polysaccharide-based polycomplexes with embedded HR are promising for the fabrication of biocidal films and coatings.

We examined the rheological properties of polyacrylonitrile (PAN) solutions in seven solvents over a wide range of shear rates. These solutions were characterized using the Hansen solubility parameter. The vis-cosity of these dilute solutions was primarily determined by this parameter. However, above the cross-over point (at c[g] > 0.7) not only viscosity but also nature of the solvents was found to be an important factor. At high polymer concentrations, certain solutions showed gelation tendency.This study aims to determine a correlation between the rheological properties of the solutions and the affinity of the solvent with PAN. These correlations are present for an intrinsic viscosity (or the Huggins constant), a second virial coefficient, and solubility parameter. However, in certain cases, experimental points do not correspond to general dependence. This is also observed for these solutions when present-ing the data of viscoelastic measurements in G0-G00 coordinates: certain points deviate from the general dependence.A detailed infrared spectroscopy analysis has been used for examining these experimental results. It has been shown the water presence in the solvents and polymer solutions even than anhydrous solvents were used. Water presence tend to a solvent-water associate formation in the solutions. The solubility of PAN in these solvents and the gelation tendency depends on the polymer concentration, in addition to the structure and stability of the polymer-water associates. The experimental results obtained and the reported correlation made it possible to develop a subsequence of solvents used as per their affinity with PAN. The charactristics of dilute solutions were compared with the rheological properties of moderately concentrated solution.(c) 2022 Elsevier B.V. All rights reserved.

The influence of microbarite additive on the rheological properties of semidilute aqueous-saline solutions of two samples of carboxymethyl cellulose with high degree of substitution (polyanionic cellulose) and strongly different molecular mass (76 × 103 and 665 × 103) has been investigated by means of rotational viscometry and rotational rheometry. It has been shown that the introduction of microbarite in the solutions of high-molecular polyanionic cellulose leads to flocculation followed by precipitation, which is accompanied by the decrease in the systems viscosity. In the case of solutions of low-molecular polyanionic cellulose, the introduction of the additive has favored the formation of visually uniform systems stable during prolonged keeping and the increase in viscosity. In both cases, the introduction of microbarite in the solution altered its viscoelastic properties. The obtained results have evidenced the formation of polyelectrolyte–colloid complexes of different structure upon the interaction of microbarite particles and the chains of polyanionic cellulose of different length, which results in the change in the rheological properties of the solutions.

Aqueous dispersions of mixtures of low-viscosity polyanionic cellulose with microbarite are studied by viscometry, rotational rheometry, dynamic light scattering, and laser microelectrophoresis. Owing to the interaction of the polymer with microbarite particles, the hydrodynamic size of the particles and their electrophoretic mobility increase, which indicates the formation of polymer-colloidal complexes. In the mode of semidilute polymer solutions, the introduction of microbarite additives is accompanied by a significant increase in viscosity and the resulting compositions are sedimentation stable for 2 days. The frequency dependences of the storage modulus and the loss modulus show that complexation leads to a strong structuring of the system.

The behavior of composites based on block copolymers of styrene and 4-vinylpyridine and spherical gold nanoparticles in dimethylformamide is studied by static and dynamic light scattering, as well as small-angle X-ray scattering. In the absence of nanoparticles, the copolymer with a molar mass of about 104 g/mol synthesized by controlled radical reversible chain transfer polymerization forms micelles from a small number of chains in a medium that is a good solvent for both blocks. At the same time, the sol of nanoparticles stabilized with tetraoctylammonium bromide in dimethylformamide forms floccules tens of nanometers in size. The addition of the block copolymer leads to the destruction of floccules and stabilization of nanoparticles in micelles with a radius of about 5 nm. An even more efficient way to obtain stable composites is the ligand exchange of a low molecular mass nanoparticle stabilizer for the block copolymer in a tetrahydrofuran–ethanol mixed solvent. Such a composite has good film-forming ability, and the concentration of gold nanoparticles in it can be increased by centrifugation to at least 43 wt %. After the transfer of the composite to dimethylformamide, micelles with a wide size distribution are formed, the average size of which is about 10 nm. The stabilizing ability of the block copolymer decreases with a decrease in the content of 4-vinylpyridine units which provide interaction with the surface of gold nanoparticles.

Complexation in aqueous salt-free semidilute solutions of poly(styrenesulfonic acid) and poly(ethylene oxide) leading to the formation of soluble poly(styrenesulfonic acid)–poly(ethylene oxide) complexes is studied. It is shown that the interaction of the components in such complexes significantly weakens with an increase in temperature, as well as with a decrease in the poly(ethylene oxide) chain length. Using viscometry and light scattering, it is demonstrated that, in dilute aqueous and aqueous-saline solutions, no complexes are formed between poly(styrenesulfonic acid) and poly(ethylene oxide) and the system is a compatible mixture of the polymers in a common solvent.

Nanocomposites based on CdSe or CdSe/ZnS quantum dots (QDs) and poly(methyl methacrylate) (PMMA) of different molecular weights and functionality were synthesized by ligand exchange of oleic acid with RAFT-based PMMA. The successful ligand exchange was confirmed by dynamic light scattering in combination with the approach "macromolecules-ghosts" and transmission electron microscopy. Comparative study of mono- and telechelics of PMMA revealed the similarities and differences in their behavior in formation of complexes with QDs and the optical properties of the corresponding nanocomposites. Telechelics exhibited higher efficiency in the complex formation and seemed to be promising candidates for the construction of devices based on QDs and polymer matrix for optical applications.

Interaction of the anionic copolymer of acrylic acid and acrylamide with a molar ratio of monomer units of 75 : 25 and poly(N,N′-diallyl-N,N′-dimethylammonium chloride) in aqueous solution is studied. The interaction is accompanied by the formation of a polycomplex stabilized by multiple salt bonds between oppositely charged groups of both polyelectrolytes. A nonstoichiometric polycomplex with a tenfold excess of anionic groups is present in solution in the form of particles with a diameter of about 300 nm; the particles retain their aggregate stability for 30 days. The application of aqueous solutions of individual polymers and the nonstoichiometric polycomplex on the surface of sand with a particle size of 0.15 ± 0.05 mm is associated with the formation of composite polymer-sand coatings. The highest mechanical strength is possessed by coatings with the participation of an anionic copolymer and a polycomplex. For sand and polycomplex coatings, the weight loss during water treatment is 10%, which is lower than that in the case of traditional polyacrylamide soil stabilizer. The polycomplex at a concentration of up to 0.33 wt % does not exhibit toxicity to microorganisms, thereby indicating that the use of a negatively charged polycomplex is promising for obtaining waterproof protective coatings on the surface of sandy soils.

Positively charged linear chitosan molecules were cross-linked with sulfate-anions to form chitosan nano-particles which were used as a scaffold of negatively charged cardiolipin/egg lecithin liposomes loaded with doxorubicin (DOX). Thus formed multi-liposomal complexes (MLCs) containing 55 liposomes/chitosan and bearing a slight positive net charge effectively transmitted DOX into the cytoplasm of cells in culture. The efficiency of DOX delivery increased 4-5-fold upon drug incorporation in MLCs. Inside the cells, the penetrated MLCs released DOX thus enabling its accumulation in the nuclei and interaction with its intracellular target DNA leading to a decrease in cell survival. The effects were demonstrated on 3T3 line of mouse fibroblasts, drug sensitive tumor MCF-7 cells and drug resistant human ovarian carcinoma OVCAR-8 cells (formerly called MCF-7/ADR). Thus, MLC particles can be used for effective delivery of payloads in cells of different origin.

Polystyrene (PS) containing a terminal thiol group has been synthesized to create composites with CdSe and CdSe/ZnS quantum dots (QDs). Reversible addition fragmentation chain transfer (RAFT) polymerization carried out using asymmetric agent enables a facile synthesis of monochelic macromolecules with functional terminal groups. Modification of the terminal groups does not practically change the polymer molecular weight and the narrow molecular weight distribution. The interaction of the thiol group with the QD surface results in the partial substitution of low molecular weight ligands by macromolecules. The process of the formation of polymer - QD complex in the sol was studied by means of static and dynamic light scattering. The size and morphology of polymer - QD complex in the sol is compared with those in the solid films. Several possible models of the packing of polymer - QD complex are discussed. (C) 2019 Elsevier B.V. All rights reserved.