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We report synthesis of colloids with polymer core and inorganic shell consisting of silver nanoparticles (AgNPs) which can be used as building blocks for the preparation of conducting composite films. Polymer colloids based on copolymer of styrene and butyl acrylate with variable film formation temperature and functional surface have been prepared by surfactant-free emulsion polymerization. Polymer particles with average size between 140 nm and 220 nm and narrow size distribution were used as templates for deposition of AgNPs by microwave-assisted reduction of silver precursors in aqueous medium. The loading of the AgNPs on the polymer particle surface has been increased up to 60 wt.-%. Obtained hybrid colloids were used for preparation of composite films. The electrical conductivity of the composite films starts to increase if the AgNPs loading on the polymer particle surface is above 20 wt.-%.

Microgel–clay composite particles were prepared by one-step surfactant–free precipitation polymerization. Laponite nanoparticles present in the reaction mixture become encapsulated during the microgel formation process. Microgel–clay composites based on poly( N -vinylcaprolactam- co -acetoacetoxyethyl methacrylate) containing different amount of incorporated clay nanoparticles were synthesized. The clay content was varied from 2 wt% to 18 wt%. The extremely high incorporation efficiency of the clay nanoparticles into microgels was detected. The size of the hybrid microgels was decreased from 700 nm to 100 nm by increase of the clay concentration in the reaction mixture. Obtained hybrid microgels exhibit negative surface charge and excellent colloidal stability. Microgel–clay composite particles display temperature-sensitive behaviour in water. The swelling degree of the hybrid microgels decreases with increase of the clay loading. Microgel–clay composite particles exhibit temperature-controlled uptake of the cationic dye, Methylene blue, and can be used as scavenger systems in aqueous media.

The properties of amphiphilic polyether macromonomers and their behaviour during homo-polymerisation in water and in water/benzene mixture are reported. Homo-poly(glycidol) macromonomer bearing polymerisable p -vinyl benzyl end groups (PGl55-St) and two block poly(glycidol)- b -poly(glycidyl phenyl ether) macromonomers, containing polymerisable p -vinyl benzyl end groups attached to the hydrophobic (PGl52- b -PGlPhE8-St) or hydrophilic (PGlPhE9- b -PGl54-St) block were used for investigations. DLS measurements showed formation of micelles by all macromonomers, what is the reason for enhanced homo-polymerisation. In water the polymerisation initiated with 4,4′-azobis(4-cyanovaleric acid) was fast, while macromonomer conversion was over 90%. Introduction of benzene to the polymerisation system resulted in formation of swollen (less packed) micelles and to a decrease of the local concentration of double bonds in the micelle core. As a result the decrease of reaction rate followed by longer polymerisation time in case of PGl55-St and PGl52- b -PGlPhE8-St was observed. Nevertheless, their conversion remained high and varied from 95 to 10. In contrast for PGlPhE9- b -PGl54-St increase of polymerisation rate, accompanied by slight increase of conversion was observed for homo-polymerisation in water/benzene mixture.

Preparation of core–shell particles consisting of polystyrene–poly(ethylene glycol) monomethacrylate (PS–PEGMA) core covered with polypyrrole (PPy) shell is described. The thickness of PPy shell, which strongly influences electrical properties of the films prepared from the particles, can be varied by changing pyrrole load, controlling the overall template surface area in the system and by influencing the pyrrole polymerization kinetics in the presence of different oxidants. The type of anions and PPy loading strongly influence the electrical conductivity. Typical value of the resistivity of thin film consisting of core–shell particles was 34 Ωm (PPy oxidized by FeCl 3 , shell thickness 3 nm). Current–voltage dependences of low conductivity samples (thin PPy shell layer) are characteristic of contact-limited currents. The conductivity of the particles changes with humidity, which can be utilized in humidity sensors.

In present article, we demonstrate that aqueous microgels can be used as containers for the in-situ synthesis of hydroxyapatite. The hydroxyapatite nanocrystals (HAp NCs) become integrated into microgels forming hybrid colloids. The HAp NCs loaded in the microgel can be varied over a broad range. The HAp NCs are localized within the microgel corona. The deposition of the inorganic nanocrystals decreases the colloidal stability of the microgels and leads to particle aggregation at high HAp NCs loading. Because of the strong interactions between HAp NCs and polymer chains, the swelling degree of microgels decreases, and temperature-sensitive properties disappear at high loading of the inorganic component. We demonstrate that hybrid colloids can be used as building blocks for the preparation of nanostructured films on solid substrates.

The adsorption and self-organization process as well as the surface reactions of several bifunctional adhesion promoters on different oxide surfaces have been investigated. The aim was to improve the adhesion between metal oxides and different organic coatings. We developed a large number of bifunctional compounds, which are able to adsorb spontaneously on different pre-treated metal (oxide) surfaces. The second group can be designed for grafting different otherwise incompatible layers. Therefore, a special two-step procedure has been developed: (1) adsorption of the designed bifunctional molecules on the substrate and (2) surface reaction of the terminal reactive group with a polymeric top coating or with further monomers resulting in a strongly bond composite. For this purpose substances were chosen having a surface reactive group, an aliphatic spacer and a reactive group for a suitable top layer. Phosphonic acids forming strong bonds with several metal surfaces were chosen as surface-active groups on metal oxide substrates. The termination of these compounds with further reactive groups opened a wide range of possible applications. Functionalities like amino or carboxylic groups allowed reactions with commercial lacquers (e.g., polyurethane) for improving adhesion promotion and corrosion inhibition of the metal substrates. By using polymerizable groups like thiophene and pyrrole an in situ surface polymerization with further monomers is possible directly on the substrate. The adsorbed films of bifunctional phosphonic acids on metal (oxide) substrates were characterized by contact angle measurements, X-ray photoelectron spectroscopy (XPS), the surface polymerized films were investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), cyclovoltammetry (CV), and electrochemical impedance spectroscopy (EIS). The results showed that monolayers were formed, which were correctly oriented on the surfaces: the phosphonic acid group was attached to the substrate whereas the terminal group was free standing for further reactions. Surface polymerization with additional monomer was possible either chemically or electrochemically resulting in smooth polymer layers of adjustable thickness. The conducting polymers were found to be p-conductive with a doping level of about 30%. Conductivity measurements revealed a conductivity of about 0.13 S/cm for the best films. Based on this principle two possible applications are given: firstly, a corrosion protecting system for steel, and secondly, a model release system for protecting steel after damage of the coating.

This paper presents the first results of a project aimed at investigating the arrangement of polyelectrolyte layers on unalloyed steel. We studied the structure of double and single polymer layers consisting of cellulose phosphate (HP-PP-C) and polyethyleneimine (PEI). Layers were characterized by variable angle ellipsometry, AFM and XPS. In particular, XPS indicated the incorporation of iron ions into cellulose phosphate layers, but, in contrast, these ions could not be observed in PEI layers. Results indicated that the homogeneity and qualitative corrosion performance of double layers (HP-PP-C/PEI) on unalloyed steel depend on the deposition of cellulose phosphate at the interface with steel.

In the present paper, we describe the preparation of hybrid particles consisting of polymeric core with deposited hydroxyapatite (HAp) nanocrystals. Polystyrene submicron particles modified by β-diketone groups have been used as templates for the growth of HAp. Hybrid particles with HAp nanocrystal content between 7 and 50 wt% have been prepared. Microscopy studies indicate that hybrid particles exhibit “raspberry” morphology, and HAp nanoparticles are not homogeneously distributed on the polymer particle surface. The increase in the HAp content on the polymer particle surface reduces the colloidal stability of the hybrid particles because of the vanishing of the surface charge.

In this article, we report the preparation of a kind of novel crosslinked ultrafine fiber by electrospinning of unsaturated polyester macromonomers (UPM) and subsequent thermal crosslinking. The UPM is prepared via a two-step reaction with poly(2-methyl-1,3-propyleneadipate) diol terminated (PMPA), isophorone-diisocyanate (IPDI) and 2-hydroxyethyl methacrylate (HEMA). Poly(3-hydroxyl-butyrate-co-3-hydroxylvalerate) (PHBV) is chosen to improve the processability of the UPM. UPM/PHBV blend ultrafine fibers are successfully electrospun with a proper mass ratio of UPM to PHBV in dichloromethane solution. The fibers are thermally crosslinked after electrospinning. Measurement results indicate that the average diameter of the fibers is about 1 μm and the crosslinked fibers have good solvent-stability and thermal-stability. This novel fiber has potential applications in filtration and protective coating. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 107:2142–2149, 2008

In the last decade there has been a steady increase in the number of publications describing the synthesis, characterization and applications of hybrid particles. Colloidal aqueous microgels form an important subdivision of polymer colloids used for the deposition of different functional materials. Due to their numerous attractive properties, microgel particles have been used as templates for the synthesis, storage and transportation of nanostructured materials. This paper reviews the important developments in the area of composite microgels over the last decade, and is limited to microgel particles operating in aqueous media. The patent literature is not included in the review. Different synthetic approaches as well as some properties and applications of composite microgels are discussed. Copyright © 2006 Society of Chemical Industry

Novel temperature- and pH-responsive microgels based on poly(vinylcaprolactam-co-acetoacetoxy methacrylate) (VCL/AAEM) functionalized with vinylimidazole (VIm) has been prepared in aqueous medium using simple batch dispersion polymerization procedure. Obtained microgel particles are characterized by narrow particle size distribution and their hydrodynamic radius can be varied from 200 to 500 nm (pH = 6, T = 20 °C). The T- and pH-sensitivity of obtained particles can be easily tuned by the variation of the Vim content in the copolymer structure. Increase of VIm content in the microgel structure led to increased swelling of the microgels in acidic medium and strong shift of the volume phase transition temperature to higher temperatures. It has been found that sedimentation behavior of obtained microgels is strongly pH-dependent, and this effect can be used for controlled particle separation.

In the present paper composite polymeric particles with polypyrrole (PPy) shell have been examined as reservoirs for uptake of amino acids. The particle morphology can be designed in a way that polypyrrole load on the particle surface as well as the PPy shell thickness can be varied easily by control of the pyrrole polymerization conditions, such as monomer concentration and choice of different oxidants. Three different oxidants have been used for the preparation of PPy outer-layers, namely FeCl3, Na2S2O8, and H3PMo12O40, which give the possibility to incorporate different anions into PPy structure. l - and d -alanine uptake in the presence of obtained particles has been tested as a function of particle concentration and PPy amount on the particle surface. It has been found that composite particles can adsorb quite high amounts of alanine and even show certain enantioselectivity. The uptake efficiency and selectivity depend strongly on the properties of the PPy layer, such as chemical structure (oxidized or overoxidized state) and the nature of the dopant anion.

A series of high clay content Laponite XLS/ polyacrylamide (PAAm) nanocomposite hydrogels (S-M gels) with excellent resilience, low elastic hysteresis, and ultrahigh elongation, have been successfully synthesized. Based on our results, it is concluded that the mechanical properties ofnanocomposite hydrogels probably depend to a great extent on the hydrophilicity and flexibility of the macromolecules. More, over, his found that the transparency during the in-situ polymrization of S-M gels does not change, which is quite different from clay/poly(N-isopropyl-acrylamide) nanocomposite hydrogels.

Hybrid microgels functionalized with silver nanoparticles (AgMP) have been prepared and their physico-chemical properties examined. Composite have been obtained by formation of AgNP in presence of poly[vinylcaprolactam-co-(acetoacetoxyethyl methacrylate)] (VCL/AAEM) microgel particles. It has been demonstrated that hybrid particles with different AgNP amounts can be prepared. Hybrid particles are sensitive to temperature and swelling, and collapse processes are reversible. Incorporation of AgNP leads to shrinkage of microgel template due to the partial immobilization of polymer chains on the microgel surface. As a consequence, gradual loss of temperature sensitivity is observed. Hybrid microgels form highly transparent well-organized films on solid substrates, providing homogeneous distribution of AgNP in bulk materials. Presence of AgNP increases considerably the thermal stability of composite films.

In the present paper, we investigate the preparation of polymeric particles based on the biodegradable polyester poly(3-hydroxybutyrate- co -3-hydroxyvalerate) (PHBV). A new technique for PHBV particle preparation has been developed. This method utilizes the thermoreversible gelation of PHBV in toluene. Particles have been obtained by the secondary dispersion technique in a three-step procedure: (a) preparation of PHBV solution in toluene; (b) preparation of O/W emulsion by ultrasound followed by the gel formation in toluene/PHBV droplets; and (c) toluene extraction. In the present study we investigated the influence of the stabilizer type and its concentration in the aqueous phase, ultrasound power, and PHBV concentration in toluene on the size and stability of the formed droplets as well as the final PHBV particles. It has been found that PEO/PS block copolymers are the best stabilizers for the present system as compared to conventional tensides such as SDS or CTAB. It has been found that PEO/PS block copolymers allow obtaining PHBV particles with a regular shape and controlled dimensions after toluene extraction. The minimal size of the PHBV particles obtained by this technique was ca. 100 nm. The obtained particles exhibit a relatively broad particle size distribution and the particle shape is strongly affected by the block copolymer composition, ultrasound power and the way of toluene extraction.

In present paper we investigate thermoreversible gelation of biodegradable polyester poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) in toluene. Hot PHBV solutions became transparent gels after cooling to room temperature. This physical gelation process was followed by light scattering and viscosity measurements for solutions of different PHBV concentrations. It has been found that gelation temperature increases with increasing polymer concentration in toluene. PHBV films have been prepared by gelation process followed by solvent removal on solid substrates. It has been demonstrated that PHBV concentration in the solution influences the surface morphology of obtained films. Homogeneous PHBV films with increased surface roughness can be obtained by means of developed technique. Hydrolytic degradation studies indicate that surface morphology of obtained PHBV layers changes considerably with degradation time.

We report on a preparation of hybrid particles with polymeric cores and ZnS shells. Two types of monodisperse sterically stabilized polystyrene particles with hydroxyl-terminated PEG chains (PS/PEGMA) or β-diketone groups (PS/AAEM) on the surface have been prepared and characterized. Formation of ZnS layer on the surface of submicron particles has been studied by SEM and EDX. Deposition of ZnS on the surface of PS/PEGMA particles is not uniform and leads to formation of ‘raspberry’ morphology with rough surface. It has been found that presence of β-diketone groups on the particle surface leads to formation of well-defined ZnS layers. It has been assumed that such effect is due to the complexation of Zn cations by β-diketone groups leading to nucleation and growth of ZnS crystals on the polymer particle surface. Polymeric particles were completely covered with ZnS if the loaded amount of inorganic material was higher then 40 wt%. The thickness of ZnS layer on the particle surface can be easily varied by changing the ZnS load (in present study maximal thickness of the ZnS shell was 70 nm). It has been found that increase of the ultrasound power leads to considerable increase of the ZnS deposition on the particle surface without strong changes of the particle morphology. Hybrid particles have been investigated with XRD technique and their optical properties were studied by UV-spectroscopy. The colloidal stability of obtained particles was studied by separation analyser. Sedimentation experiments indicate that colloidal stability of obtained composite particles depends strongly on loaded ZnS amount and pH value of the aqueous medium. It has been found that highest sedimentation velocities (or maximum of instability) were determined by ZnS loads, which provide complete coverage of the particle surface. Increase of the ZnS layer thickness led to better stability of hybrid particles in aqueous medium.

We report on a preparation of hybrid microgels filled with ZnS inclusions. Temperature-sensitive poly(N-vinylcaprolactam-co-acetoacetoxyethyl methacrylate) (VCL/AAEM) microgels have been used as containers for deposition of ZnS by reaction of zinc acetate and thioacetamide under ultrasonic agitation. ZnS was deposited directly into microgels, leading to formation of composite particles which exhibit temperature-sensitive properties, high ZnS contents, and excellent colloidal stability. The influence of ZnS load on microgel size, morphology, swelling−deswelling behavior, and stability is discussed. Hybrid particles contain up to 20 wt % of ZnS, and particle stability decreases with increase of inorganic filler content. Detailed microscopy investigations confirm incorporation of ZnS nanoparticles into microgel network. The possibility of self-assembly of hybrid particles on different surfaces was studied. It has been found that microgels filled with ZnS can form organized particle arrays after water evapora...

Stable polypyrrole dispersions were prepared by chemical oxidative polymerization of pyrrole in an aqueous medium containing different anionic salts - sodium benzoate, potassium hydrogen phthalate and sodium hydrogen succinate. Results of the elemental analysis and FT-IR spectroscopy confirmed that the anionic salts are incorporated in the conducting polymers and functioned as the dopants. The retardation of pyrrole polymerization was observed when a certain amount of the salt was used as dopant. SEM images of polypyrrole dispersions indicate large spherical particles (150-180nm). The conductivity of polypyrrole composites has also been investigated.

Behaviour of temperature-sensitive core–shell VCL/AAEM microgels has been studied in binary alcohol/water mixtures. Amount of alcohol in binary mixture influences strongly the swelling and thermo-sensitive properties of microgels. Alcohol induces swelling of VCL-rich microgel shell leading to larger dimensions of microgel particles and larger surface area. Under these conditions pyrrole polymerization was carried out, and the influence of pyrrole concentration, oxidant nature and temperature on morphology and properties of composite particles was investigated. Contrary to the polymerization in water medium, this selective swelling method gives possibility to increase three times loaded polypyrrole amount and maintain the stability of the colloidal system. It was found that in case when persulfate was applied as oxidant it is possible to vary effectively the particle size of composite microgels by changing the ethanol concentration in water. Contrary, when FeCl3 was used as oxidant formation of secondary particles was detected leading to dispersions with bimodal particle size distribution. The conductivity of the composite particles was much higher if polypyrrole synthesis was carried out in pure water.

In the present paper, polymeric microgels have been prepared by surfactant-free emulsion co-polymerization of acetoacetoxyethyl methacrylate (AAEM) and N-vinylcaprolactam (VCL) in water with water-soluble azo-initiator 2,2′-azobis(2-methylpropioamidine) dihydrochloride (AMPA). It was found that the particle diameter decreased gradually when higher amounts of AAEM were used in monomer mixture. Obtained microgels possess lower critical solution temperature (LCST) in water solutions, so rapid decrease of the particle size was observed at elevated temperatures. As was found using simultaneous static and dynamic light scattering, microgels undergo soft sphere–hard sphere transition during heating.

In a previous paper [Polymer (2003) in press DOI: 10.1016/j.polymer.2003.09.037] polymeric temperature-sensitive microgels were prepared by surfactant-free emulsion co-polymerization of N-vinylcaprolactam (VCL) and acetoacetoxyethyl methacrylate (AAEM). In the present work, VCL/AAEM microgels were used as a template for oxidative polymerization of pyrrole (Py). It was found that pyrrole polymerization takes place directly in microgel structure leading to composite particles. Influence of microgel structure and amount of incorporated polypyrrole (PPy) on particle properties is discussed. Obtained stable composite microgels show similar thermal sensitivity as VCL/AAEM particles with fully reversible collapse-swelling properties.

Several concepts have been developed for the improvement of adhesion promotion and corrosion inhibition of reactive metal surfaces, like aluminum. The aim of these studies was to replace the present technical procedure for pretreatment of aluminum surfaces with chromium acid. Therefore, the adsorption and organization process of mono- and bifunctional alkyl phosphonic acids and mono alkyl phosphoric acid esters has been investigated. The properties of the adsorbed SAM's were confirmed by industrial linked adhesion and corrosion tests. By functionalization of the terminal position with thiophene, molecules are prepared which can graft conducting polythiophene layers via surface polymerisation on silicon/metal substrates. Also polymeric nano-particles with phosphoric acid groups form thin and smooth well-packed films on aluminum surfaces. Stable core-shell polypyrrole (PPy) dispersions were prepared by using polystyrene (PST) or poly (styrene-co-butyl acrylate) (PST-co-BuA) as the core, and polypyrrole as the shell.

Cellulose as natural and non-toxic material is very interesting for biological applications. Its poor solubility in organic solvents can be improved by introduction of long alkyl chains. Phosphate-substituted cellulose derivatives form ultra-thin layers on several metal surfaces [1, 2]. The layers were applied on the surfaces via dip coating from dilute solutions and characterised by contact angle measurements. Initial corrosion tests were performed. These polymers were applied as adhesion promoters for steel-, titanium- and hydroxy apatite surfaces. Medical implants were pre-treated by UV irradiation, coated with the cellulose derivatives and activated by hot water treatment. The adhesion of the implants surpassed that of conventionally used PMMA systems.

A new class of compounds, ω-(thiophen-3-yl) alkyl phosphonic acids, was used to link conductive polythiophene layers and several metal oxide substrates. In general, the adhesion between polythiophene films and metal substrates is insufficient for technical and microelectronic applications. The use of adhesion promoters between the substrate and the polymer enables the formation of a strongly bonded composite. Adhesive compounds were synthesized which contained a phosphonic acid group attached to the substrate and a thienyl group for surface polymerization with thiophene monomers. The properties of these created adhesion promoters were characterized on several substrates by contact angle measurements and IR investigations. First successful attempts were made to obtain a structured polymer surface via micro-contact printing.

Tert-butylacrylate was polymerized by potassium tert-butoxide in THF and toluene in the presence of 10% (by volume) of ethylene oxide. Polymers with good yields and reasonably narrow MWD (Mw/Mn∼2) were obtained. Microtacticity of the polymers is strongly solvent-dependent, the content of isotactic triads being ∼70% in toluene and ∼40% in THF. Upon using ethylene oxide as part of the solvent, diblock-copolymers of polyethylene oxide with poly-tert-butylacrylate with controlled molecular weight characteristics of the polyethylene oxide block were synthesized. The possibility of diethylvinylphosphonate polymerization on the living chain ends of poly-tert-butylacrylate was checked. At the 10% content of ethylene oxide in the reaction medium, diblock-copolymers of poly-tert-butylacrylate and polydiethylvinylphosphonate were obtained and theIR compositions were determined. Triblock-copolymers polyethylene oxide-poly-tert-butylacrylate-polydiethylvinylphosphonate with low polymerization degree of the second and ...

Polythiophene layers have been grafted onto silicon, iron, platinum and titanium for applications as organic semi-conducting films on solid surfaces. In general, the adhesion between the polymer films and substrates is insufficient for technical and microelectronic applications. The use of adhesion promoters between substrate and polymer and enables the formation of a strongly bonded composite. The polymers were synthesized by chemical or electrochemical surface polymerization.

In this work the emulsion polymerisation of styrene was carried out in presence of the inisurfs (reactive surfactants). The reaction kinetics was followed by dilatometric and calorimetric measurements. The influence of the inisurf concentration in reaction mixture as well as the reaction temperature on the particle properties were studied. Resulting particles were characterised with FFFF-MALLS and PCS. Viscosity measurements indicate the formation of particle flocks in the solution at certain inisurf concentration in reaction mixture.

The adsorption and organisation process of reactive microgels has been investigated on technical aluminium. The aim was to replace the present chromating procedure on reactive metals like aluminium because this process was been considered as an ecological problem. By means of a two-step emulsion polymerization with phosphate substituted monomer we have obtained polymeric nano-particles with phosphate groups on the surface. The core is synthesized by copolymerization from styrene (St) and butyl acrylate (BuA). The results of several analytical methods like contact angle SEM or TEM measurements showed, that these microgels were able to adsorb spontaneously onto the substrate surface and subsequently a structured molecular order was formed. The properties of the adsorbed microgel layers were confirmed by industrial linked adhesion and corrosion tests.

In recent works the self-assembly process has been investigated to replace the present chromating procedure on reactive metals like aluminium and the improve the lacquer adhesion and corrosion inhibition. These self-assembling layers were formed of small bifunctional organic molecules with phosphate or phosphonic acid groups attached to the metal substrate. The idea of this work was to apply these results and techniques to cellulose derivatives on implant metals. The formation of ultra-thin layers of phosphorylated cellulose derivatives has been reported previously. These ultrathin layers were built on metal substrates like aluminium, titanium or steel for adhesion promotion and corrosion inhibition. Hydroxypropyl-2-phosphatepropyl cellulose was synthesised for adhesion on hydrophilic metallic surface. Hydroxypropyl-2-cinnamoylpropylester cellulose was prepared in order to crosslink the adsorbed layers. The layers were formed on metal surfaces via dip coating from dilute solutions and characterised by means of contact angle measurements, SEM investigations and FT-IR spectroscopy. Initial corrosion tests were performed.

The polymer peroxide surfactants obtained by copolymerization of a perox- ide monomer with maleic anhydride were either physically or chemically sorbed on the dispersed-phase surfaces, for example, on mineral fillers and latex particles. Subse- quent initiation of graft copolymerization from the surface resulted in the formation of interfacial compatibilizing polymer layers in water emulsions and dispersed-filled polyethylene. The morphology of the resulting filled polymer was characterized by scanning electron microscopy. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1228 - 1239, 2000

The self-assembly process has been investigated for the replacement of the present chromating procedure on reactive metals like aluminium and to improve the lacquer adhesion and corrosion inhibition. It will be shown, that self-assembled layers can affect adhesion and corrosion inhibition on aluminium and its alloys. For self-assembly molecules (SAMs) substances are required which are able to react spontaneously on the surface for which terminated alkyl-phosphonic and phosphoric acid monoalkyl esters have been synthesised. The best anchor groups for aluminium were ascertained by pH-dependent flotation tests, dynamic contact angle measurements and corrosion tests. Grazing angle Fourier transform infrared spectroscopy (FTIR), angle dependent X-ray photoelectron spectroscopy (XPS) and Auger measurements show the existence and orientation of these new molecular structures. Model surface reactions with isocyanates demonstrate the binding capability to the lacquer.

The adsorption and self-organisation process of alkyl-phosphonic acids and phosphoric acid monoalkyl esters on technical aluminium surfaces have been investigated by different surface sensible techniques: Grazing angle FT-IR- spectroscopy, angle dependent XPS and Auger- spectroscopy. The aim of these studies was to replace the present technical procedure for pretreatment of aluminum surfaces with chromate acid in order to improve the corrosion inhibition and the coating adhesion. The ability for self-assembly is given by substances which have a surface reactive group and a long-aliphatic or aromatic spacer and a supramolecular order is built-up between these spacers. The results show that these molecules are able to adsorb spontaneously onto the aluminum surface and subsequently a structured molecular order is formed. These effects were confirmed by industrial linked adhesion and corrosion tests.

In this work, we demonstrate an inimitable liquid crystalline template strategy for the preparation of water dispersible electrically conducting poly(3,4-ethylenedioxythiophene) nanospindles (PEDOTSs). PEDOTSs were formed during the polymerization of the spindle shaped liquid crystalline phase of “EDOT–PDPSA” which was formed by the specific interactions of 3,4-ethylenedioxythiophene (EDOT) with 3-pentadecyl phenol-4-sulphonic acid (PDPSA). Liquid crystalline phases were characterized by Polarized Light Microscopic (PLM) analyses, rheology and XRD. Morphology and solid state ordering of conducting nanospindles were characterized by SEM, TEM and XRD. PEDOTSs exhibited an electrical conductivity of � 2.79 S cm � 1 and a good thermal stability (� 300 � C), which suggests their applicability in fabricating high temperature electronic devices. Furthermore, electrochemical studies of PEDOTS modified glassy carbon electrodes (GCEs) showed an oxidation peak of ascorbic acid at a lower potential of 0.046 V with a peak current about 10 times (91.68 mA) higher than that of the bare GCE with excellent electrode stability, proposing that it can be used as a steady electrode for the electro-catalytic oxidation of similar molecules.

In present paper we demonstrate that aqueous microgels can be used as containers for in-situ synthesis of hydroxyapatite. The hydroxyapatite nanocrystals (HAp NCs) become integrated into microgels forming hybrid colloids. The HAp NCs loading in the microgel can be varied in a broad range. The HAp NCs are homogeneously distributed within the microgel corona. The deposition of the inorganic nanocrystals decreases colloidal stability of the microgels and leads to particle aggregation at high HAp NCs loading. Due to the strong interactions between HAp NCs and polymer chains the swelling degree of microgel decreases and temperature-sensitive properties disappear at high loading of the inorganic component. The hybrid colloids can be used as building blocks for the preparation of nano-structured films on solid substrates.

In the present paper, we report the preparation of hybrid temperature-sensitive microgels which include magnetite nanoparticles in their structure. Polymeric microgels have been prepared by surfactant-free emulsion copolymerization of acetoacetoxyethyl methacrylate (AAEM) and N-vinylcaprolactam (VCL) in water with a water-soluble azo-initiator. The obtained microgels possess a low critical solution temperature (LCST) in water solutions, with a rapid decrease of the particle size being observed at elevated temperatures. Magnetite was deposited directly into microgels, leading to the formation of composite particles which combine both temperature-sensitive and magnetic properties. The influence of magnetite load on microgel size, morphology, swelling-deswelling behavior, and stability is discussed.

Many technical applications require substances providing special abilities in connecting different materials to each other. Beginning from applications for corrosion inhibition to improved adhesion abilities of laquers on selected metals like aluminium, titanium or tantalum, some special adhesion promoters on base of phosponic acid and trichlorsilane were developed. At last electronic devices basing on conducting polymers need adhesion promoters to bound the conducting polymers to supporting materials consisting of technical polymers or silicon wafers and other inorganic surfaces. This requires new adhesion promoters with polymerizable groups like thiophen or pyrrol.

Stable core-shell polypyrrole (PPy) dispersions were prepared by using polystyrene (PST) or poly (styrene-co-butyl acrylate) (PST-co-BuA) as the core. and polypyrrole as the shell. SEM images showed that PPy/PST composites with a thin homogeneous overlayer of polypyrrole can he prepared when uncharged polymeric stabilizer is grafted onto the particle surface. Composite particles with raspberry morphology were obtained when the core particles were stabilized by surfactant with charge. The stability, morphology and conductivity of PPy composites have been investigated.

Water dispersible nanostructured multifunctional polyaniline-laponite-keggin iron cation composites (PPIL) were prepared by the oxidative polymerization of aniline in the presence of an aqueous dispersion of keggin iron-laponite (PIL) at room temperature. Negatively charged ions on the surface and residual positive charges on the edges of the laponite disc adsorb both keggin iron and aniline through ion-dipole and ionic interactions and can act as a micellar template during polymerisation. We suggest that keggin cages act as linkages between disorganized laponite sheets and during polymerisation, the disorganised PIL discs are co-structured and self-assembled with the formed PANI and engulfed layers and rolled sheets of nanotubes. These multifunctional composites exhibited electrical conductivity ∼ 5.7 × 10−1 S cm−1, saturation magnetization ∼ 9.0 × 10−1 emu g−1 with coercivity 8.2 Oe and thermal stability ∼ 300 °C, revealing their utility as a novel precursor for many high technological applications.

In present paper we report on a preparation of hybrid microgels filled with gold nano-particles (AuNPs). Temperature-sensitive VCL/AAEM microgels have been used as containers for deposition of Au by in situ formation of gold nano-particles. Synthesis of AuNPs has been performed by two methods: a) reduction of chloroauric acid with sodium borhydride and b) reduction of chloroauric acid by sodium citrate under ultrasonic agitation. In both cases AuNPs were deposited directly into microgels leading to formation of composite particles which exhibit temperature-sensitive properties, tunable gold contents and high colloidal stability. The influence of Au load on microgel size, morphology, swellingdeswelling behaviour and stability is discussed.