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Thermoplastic apparent interpenetrating polymer networks (thermoplastic-AIPNs) were prepared at several compositions by melting and pressing of crystallizable polyurethane (CPU), based on butylene adipate glycol (BAG), and styrene/acrylic acid random copolymer [...]

The review is devoted to analysis of the publications in the area of synthesis of polymeric membranes according to the technique of molecular imprinting as well as investigation of their properties. Different types of the molecularly-imprinted polymer membranes are described and the main techniques for their synthesis are analyzed. The review is also concentrated on the application of the molecularly imprinted polymer membranes for the development of new analytical methods. [ABSTRACT FROM AUTHOR]

The study of dielectric properties and molecular dynamics in Polyurethane (PU), Poly(hydroxyethyl methacrylate) (PHEMA) and in semi-IPNs based on PU and PHEMA synthesized by photopolymerization are presented. The results of broadband dielectric spectroscopy (BDS) investigation are compared with results of investigation by dynamic mechanical analysis(DMA) with the goal to have a better insight on the dynamic of the chain and their relation with the structure. The relaxation maps for investigated PU, PHEMA and semi-IPNs were built. [ABSTRACT FROM AUTHOR]

Investigates the surface properties of semi-interpenetrating polymer networks based on polyurethane and polyvinyl pyrrolidone (PVP). Emphasis on thermodynamic characteristics, morphology, mechanical properties and surface properties; Increase in the amount of PVP in the system; Usefulness of bacterial adhesion for biomedical material applications.

Investigation of a scale factor effect on adhesion and viscoelastic properties of adhesive based on epoxy resin curried with polyamine was carried out. By using dynamic mechanical analysis method the viscoelastic behavior of both free epoxy films and adhesive joints in whole was studied. The sickness of adhesive layer and free films as a scale factor was varied in interval of 50-900 mkm. The increase of epoxy adhesive layer thickness was shown to result in the nonmonotonic decrease in an adhesive strength value. The dramatic drop of adhesion strength was observed for adhesive layers having thickness less 200 mkm and more slowly degradation occurred in case of thicker ones. Along with this the correlation between adhesive layer thickness and polymer ability to dissipate mechanic energy took place. It was also shown that layer thickness influenced not only adhesion and viscoelastic behaviors of adhesive but coupled with the effect of substrate (duralumin) surface caused the changes in topology and morphology of epoxy networks. Particularly the appearance of shoulder associated with additional relaxation transition on the rising wing of the maximum at loss module temperature dependence for sample of adhesion joint with adhesive layer of 800 mkm indicated the fluctuation of cross-linking density of epoxy network. [ABSTRACT FROM AUTHOR]

Viscoelastic properties both traditional and gradient polyurethane-polyacrylate IPNs were studied. Both types of IPNs were shown to be two-phase systems inclusive considerable interphase area. It was found that GIPNs were characterized by anisotropy of viscoelastic properties specified by different structure depending on the direction of concentration gradient of acrylate component and which possessed a broad glass transition interval that defined an ability of material to dissipate the mechanical energy. By using the model imitation method the system of questions describing the GIPN formation kinetic - gradient profile generation was proposed. Property-composition correlation dependences were found that allow one to realize the transfer from concentration gradient profiles to those of distribution of properties, in particular elastic modulus, within GIPN layers. [ABSTRACT FROM AUTHOR]

Aim. Development of an easy-to-use colorimetric sensor system for fast and accurate detection of phenol in environmental samples. Methods. Technique of molecular imprinting, method of in situ polymerization of molecularly imprinted polymer membranes. Results. The proposed sensor is based on free-standing molecularly imprinted polymer (MIP) membranes, synthesized by in situ polymerization, and having in their structure artificial binding sites capable of selective phenol recognition. The quantitative detection of phenol, selectively adsorbed by the MIP membranes, is based on its reaction with 4-aminoantipyrine, which gives a pink-colored product. The in- tensity of staining of the MIP membrane is proportional to phenol concentration in the analyzed sample. Phenol can be detected within the range 50 nM-10 mM with limit of detection 50 nM, which corresponds to the concentrations that have to be detected in natural and waste waters in accordance with environmental protection standards. Stability of the MIP-membrane-based sensors was assessed during 12 months storage at room temperature. Conclusions. The sensor system provides highly-selective and sensitive detection of phenol in both model and real (drinking, natural, and waste) water samples. As compared to traditional methods of phenol detection, the proposed system is characterized by simplicity of operation and can be used in non-laboratory conditions. [ABSTRACT FROM AUTHOR]

Sodium silicate and diisocyanate based organic-inorganic systems were synthesized. Their formation, structure, and properties were studied by means of IR-spectroscopy, DMA, TGA, and transmission optical microscopy. During structuring of organic-inorganic composite obtained the isocyanate groups cyclotrimerization was found to take place simultaneously with urea-urethanes formation reaction. It was shown that the formation of isocyanurate cycles in composite structure resulted in emergence of additional relaxation transition in temperature dependences of viscoelastic functions. [ABSTRACT FROM AUTHOR]

Polyacrylate copolymers based porous polymer films were synthesized. Qualitative and quantitative analysis of electron microscopy images of the surface of obtained films were carried out. Dodecanol, cyclohexanol, low-molecular PEG, and their mixtures were shown to be effective porogens for porous materials production. [ABSTRACT FROM AUTHOR]

The method of synthesis of phenol-selective molecularly imprinted polymer (MIP) membranes was developed. The MIP membranes were used as a basis for new analytical test-systems for qualitative and quantitative detection of phenols in aqueous solutions. The developed test-systems work according to the principle of "litmus paper", while colour staining remains stable during several months. [ABSTRACT FROM AUTHOR]

Recent results devoted to methods of components compatibilization in polymer blends as well as synthesis and investigation of structure and properties of binary polymer blends was summarized and systematized. Regularities of inter- and intra-molecular physical bonds network formation and the influence on phase structure and properties of heterogeneous systems based on functionalized polymers are thoroughly considered. [ABSTRACT FROM AUTHOR]

By using the methods of the dynamic mechanical thermal analysis, X-ray scattering and scanning electronic microscopy the microphase structure and properties of water-permeable polymer films based on polyurethane-polyurethaneacrylate semi-IPNs were studied. The parameters of porous (size, form and size distribution) were found to be a function of content of linear component, and the heterogeneity level of structure and size of microareas of heterogeneity to depend in a small extent on composition of researched systems. [ABSTRACT FROM AUTHOR]

An easy-to-use colorimetric test-system for the efficient detection of creatinine in aqueous samples was developed. The test-system is based on composite molecularly imprinted polymer (MIP) membranes with artificial receptor sites capable of creatinine recognition. A thin MIP layer was created on the surface of microfiltration polyvinylidene fluoride (PVDF) membranes using method of photo-initiated grafting polymerization. The MIP layer was obtained by co-polymerization of a functional monomer (e.g. 2-acrylamido-2-methyl-1-propanesulfonic acid, itaconic acid or methacrylic acid) with N, N'-methylenebisacrylamide as a cross-linker. The choice of the functional monomer was based on the results of computational modeling. The creatinine-selective composite MIP membranes were used for measuring creatinine in aqueous samples. Creatinine molecules were selectively adsorbed by the MIP membranes and quantified using color reaction with picrates. The intensity of MIP membranes staining was proportional to creatinine concentration in an analyzed sample. The colorimetric test-system based on the composite MIP membranes was characterized with 0.25 mM detection limit and 0.25-2.5mM linear dynamic range. Storage stability of the MIP membranes was estimated as at least 1 year at room temperature. As compared to the traditional methods of creatinine detection the developed test-system is characterized by simplicity of operation, small size and low cost., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Portable biomimetic sensor devices for the express control of phenols content in water were developed. The synthetic binding sites mimicking active site of the enzyme tyrosinase were formed in the structure of free-standing molecularly imprinted polymer membranes. Molecularly imprinted polymer membranes with the catalytic activity were obtained by co-polymerization of the complex Cu(II)-catechol-urocanic acid ethyl ester with (tri)ethyleneglycoldimethacrylate, and oligourethaneacrylate. Addition of the elastic component oligourethaneacrylate provided formation of the highly cross-linked polymer with the catalytic activity in a form of thin, flexible, and mechanically stable membrane. High accessibility of the artificial catalytic sites for the interaction with the analyzed phenol molecules was achieved due to addition of linear polymer (polyethyleneglycol Mw 20,000) to the initial monomer mixture before the polymerization. As a result, typical semi-interpenetrating polymer networks (semi-IPNs) were formed. The cross-linked component of the semi-IPN was represented by the highly cross-linked catalytic molecularly imprinted polymer, while the linear one was represented by polyethyleneglycol Mw 20,000. Extraction of the linear polymer from the fully formed semi-IPN resulted in formation of large pores in the membranes' structure. Concentration of phenols in the analyzed samples was detected using universal portable device oxymeter with the oxygen electrode in a close contact with the catalytic molecularly imprinted polymer membrane as a transducer. The detection limit of phenols detection using the developed sensor system based on polymers-biomimics with the optimized composition comprised 0.063 mM, while the linear range of the sensor comprised 0.063-1 mM. The working characteristics of the portable sensor devices were investigated. Storage stability of sensor systems at room temperature comprised 12 months (87%). As compared to traditional methods of phenols detection the developed sensor system is characterized by simplicity of operation, compactness, and low cost., (Copyright 2009 Elsevier B.V. All rights reserved.)