FA Monomer Research Articles

Rotational Spectroscopy of 2-Furoic Acid and Its Dimer: Conformational Distribution and Double Proton Tunneling.

Structural and tunneling properties of the 2-furoic acid (FA) monomer and dimer were investigated using rotational spectroscopy and DFT calculations. CREST, a conformational ensemble space exploration tool, was used to identify all possible low-energy conformations of the FA monomer and dimer, followed by the DFT geometry optimization and harmonic frequency calculations. Broadband rotational spectra in the 2-6 and 8-12 GHz regions were recorded in a supersonic jet expansion. The monomeric FA was found to exist dominantly as three different conformers: I, II, and III in a jet, with I and II taking on the cis-COOH configuration while III having the trans-COOH configuration. For the FA dimer, only the I-II conformer was observed experimentally, whereas the symmetric I-I and II-II conformers were not observed because of their zero dipole moments. The analysis of the splittings in the rotational transitions of I-II allowed one to extract the tunneling splitting to be 1056.0(12) MHz. The barrier height was determined to be ∼442 cm-1 using the scaled potential energy scans at several different levels of theory.

FURANIUM COMPOSITE MATERIAL BASED ON TALL OIL AND ITS FATTY ACIDS

A new polymer composite material based on furfural-acetone monomer, crude tall oil and its fatty acids, which are waste from the pulp and paper industry, was obtained. In this paper, the effect of crude tall oil and its fatty acids on furfural-acetone monomer binder in a composite material is considered. The composition for the composite material, consisting of FA monomer, filler and catalyst p-toluenesulfonic acid, was modified with crude tall oil additives or tall oil fatty acids. It was shown that the compressive strength of composite samples after 30-day exposure at room temperature, obtained with a reduced amount of furfural-acetone monomer and the introduction of 100% fatty acids of tall oil from the furfural-acetone monomer content, increases by 37%, with the introduction of 150% fatty acids of tall oil, the strength increases slightly - by 1.5%, but the density increases significantly and water absorption decreases with respect to the standard sample. Additives of crude tall oil (up to 150% of furfural-acetone monomer) lead to an increase in density, a decrease in water absorption - by 84%, but reduce the compressive strength of samples by 12%. The improvement in the physicochemical properties of the composite material was explained by the alleged chemical interaction of tall oil fatty acids with mono- and difurfurilideneneacetone (furfural-acetone monomer), which takes place with the formation of new polymers. This is confirmed by DTA data, chromatograms of the furfural-acetone monomer - fatty acids of tall oil (TLC) mixture, and IR spectra. The use of fatty acids of tall oil or crude tall oil, non-expensive, non-toxic products of natural origin in the composite material, can reduce the consumption rates of furfural-acetone monomer and improve the quality of the polymer.

Fabrication of polymer carbon nitride with organic monomer for effective photocatalytic hydrogen evolution

Utilization of solar heat radiation into chemical energy is attributed to semiconductor photocatalyst under sunlight perspective considered as a reversing inspired approach that exacerbates the environmental problems. Recently, our group indicates graphitic carbon nitride (g-CN) by a progressive molecular aggregation co-polymerization process that propagated with a nanoscopic organic conjugated heterocyclic monomer to enhance its photocatalytic activity. This work aims to present a facile induced co-condensation technique and used 2, 6-Furandicarboxylic acid (FA) monomer as demonstrator within g-CN that boosting the photocatalytic properties under solar energy driven caused the reduction of water. The as-prepared samples were demonstrated for various characterizations along with computational evaluation of pure and doped g-CN. The result signifying the integration of organic FA monomer in the triazine core shell of g-CN restoring a substantial delocalization in its π-conjugated system. Meanwhile, after this alternation, an identifiable undulation occurred in the surface area, electronic structure, calculated band gap, chemical composition analysis of g-CN, and also improved its electronic generation process under the visible light radiance. Besides, this unrepeatable integrity of FA co-monomer with ing-CN matrix considerably enhanced the photocatalytic activity toward Godspeed and as such, the superior photocatalyst CN/FA12.0 stimulated a tremendous photocatalytic activity of water reduction with 10.6 enhanced catalytic performances as a contrast of pristine sample respectively.

A study of the viscosity of phenol–formaldehyde resin modified with furfural–acetone monomer FA

The results of an evaluation of the relative and dynamic viscosities of phenol–formaldehyde resin modified with furfural–acetone monomer FA monomer are presented. That there is increasing viscosity of the modified adhesive composition is established due to the formation of polycomplexes, these being new supramolecular structures with increased dimensions of macromolecules of higher molecular mass.

Amphiphilic pentablock copolymers and their blends with PDMS for antibiofouling coatings

Well-defined amphiphilic pentablock copolymers Siy-(EGx-FAz)2 composed of polysiloxane (Si), polyethylene glycol (EG), and perfluorohexylethyl polyacrylate (FA) blocks are synthesized by ATRP of FA monomer starting from a difunctional bromo-terminated macroinitiator. Diblock copolymers EGx-FAz are also synthesized as model systems. The block copolymers are used, either alone or blended with a PDMS matrix in varied loadings, to prepare antibiofouling coatings. Angle-resolved XPS and contact angle measurements show that the coating surface is highly enriched in fluorine content but undergoes reconstruction after contact with water. Protein adsorption experiments with human serum albumin and calf serum highlight that diblock copolymers resist protein adhesion better than do pentablock copolymers. Blending of the pentablock copolymer with PDMS results in increased protein adsorption. By contrast, the PDMS-matrix coatings show high removal percentages of sporelings of the green fouling alga Ulva linza. © 2015 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 2015, 53, 1213–1225

Synthesis and characterization of core–shell latex: Effect of fluorinated acrylic monomer on properties of polyacrylates

A series of core–shell latexes were synthesized by seed emulsion polymerization with methyl methacrylate (MMA), butyl acrylate (BA), hydroxyethyl methacrylate (HEMA), methacrylic acid (MAA) and a novel fluorinated monomer, in which process, the novel fluorinated acrylic monomer (FA, reacting toluene diisocyanate with perfluorooctanol and HEMA) was applied in shell. FT–IR and 19F NMR spectra proved that the novel fluorinated acrylic monomer was incorporated into the copolymer chains. TEM and Dynamic light scattering (DLS) analyses demonstrated that latex particles with core–shell structure were obtained, and particle size distribution became broad after adding FA monomer. AFM measurement showed the films prepared from core–shell latexes exhibited different surface roughness; as amount of fluorinated acrylic monomer increased from 0wt% to 12wt% of total monomers in emulsion polymerization, the film surface roughness was enhanced from 0.33nm to 1.67nm, and water contact angle increased with film surface roughness. Thermogravimetric analysis demonstrated that a certain amount of FA monomer was preferable to improve thermal stability of the copolymer. Abrasion test of the films indicated that FA monomer was beneficial to increase abrasion performance of the films.

Preparation, mechanical properties and surface morphologies of waterborne fluorinated polyurethane-acrylate

A series of waterborne fluorinated polyurethane-acrylate (WFPUA) materials were prepared from polyester polyol (NJ-330), isophorone diisocyanate (IPDI), dimethylol propionic acid (DMPA) and different content of hexafluorobutyl acrylate (FA). The chemical structure was characterized with FT-IR, 1H and 13C NMR; and the result confirmed that the FA monomer had been introduced into the chain of the WPUA polymer. The physical properties of WFPUA dispersions, mechanical properties and thermal properties of WFPUA films were measured. When the content of FA monomer was 3.0wt.%, the film exhibited the highest tensile strength, hardness and excellent chemical resistance. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used for characterization of cross and surface sections of the WFPUA films to verify the results. The obtained WFPUA materials have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.

Synthesis and properties of cationic polyurethane-fluorinated acrylic hybrid latexes by emulsifier-free emulsion polymerization and the solvent-free method

A series of cationic polyurethane-fluorinated acrylic hybrid latex (PUFA) have been synthesized by solvent-free method. In the method, vinyl monomers acted as dilution agent and the polyurethane (PU) having quaternary ammonium groups acted as macromolecular emulsifier without using any other solvent and surfactant. The structure and properties of PUFA were characterized by Fourier transform infrared spectroscopy (FT-IR), F19 nuclear magnetic resonance (F19 NMR), particle size distribution (PSD) analysis, transmission electron microscopy (TEM), contact angle (CA), surface free energy analysis, scanning electron microscope (SEM) equipped with energy dispersive X-ray spectrometry (EDS), and thermogravimetric (TG) analysis. The FT-IR, F19 NMR, and EDS confirmed that the FA monomer had been introduced into the chain of the PUFA hybrid polymer. The PSD analysis indicated the particles of PUFA were smaller than corresponding pure PU dispersion and narrower in particle size distribution. The CA and surface free energy analysis proved the PUFA hybrid latex film with fluorine possessed higher contact angle and lower surface free energy in contrast with the film without fluorine. The FPUA films exhibited good surface property which could be enhanced at higher annealing temperature. The EDS of PUFA confirmed the fluorine enrichment on the surface of PUFA. TG analysis suggested the PUFA hybrid latex film had a better thermal stability than pure PU.

Novel cationic polyurethane-fluorinated acrylic hybrid latexes: Synthesis, characterization and properties

The cationic polyurethane-fluorinated acrylic (PUFA) hybrid latexes were obtained from double bond-end capped polyurethane macromonomer having quaternary ammonium groups with perfluoroalkyl acrylate (FA) by radical copolymerization. Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) confirmed that the FA monomer had been introduced into the chain of the PUFA hybrid polymer. Particle size distribution (PSD) analysis showed that the particle size of PUFA increased with the increase of the FA content. TEM indicated that the PUFA hybrid possessed core–shell structure. The analysis of the contact angles (CAs), XPS and atomic force microscopy (AFM) had shown that there was a remarkable enrichment of fluorine on the film–air interface, which was more evident when the PUFA hybrid film annealed at higher temperature. At the same time, the influences of the soft segment molecular weight, the N-methyldiethanolamine (MDEA) content and the FA content on other properties such as the surface tension of the PUFA latexes, the surface free energy of the PUFA films and the thermal properties were studied. The results showed that the MDEA content had contrary influence on latex's and film's surface properties. Thermal stabilization usually brought by fluorine was not observed in our investigated systems.

The use of furan oligomers for modifying phenol-formaldehyde resin in plywood industry

The modification of phenol-formaldehyde resins by furan oligomers to increase the service characteristics of plywood and plywood products has been suggested. The strength properties, water resistance, fire resistance of plywood based on phenol resin SFZh-3013 modified by furfural-acetone FA monomer at the stage of the mixing of the adhesive composition components have been estimated.

Preparation and Surface Properties of Fluorinated Acrylates Copolymers

Copolymerization of acrylates and styrene (St) with perfluorooctylacyloxyethyl methacrylate (FA) monomer, prepared from the reaction of perfluorooctanoic acid and hydroxymethyl methacrylate, was carried out by solution polymerization. The fluorinated acrylate and St copolymers (PFA) were examined by GPC, FT-IR, and 1H NMR. The surface tension of the PFA solution in N-methyl pyrrolidone was tested by the drop volume method. The results showed that the surface tension of the PFA solution decreased in exponential decay with increase of the PFA concentration, and the surface tension of the solution also decreased with increased addition of the FA monomer in the copolymer at the same concentration. Meanwhile, the adsorption of the PFA macromolecules in the air–solution interface increased and enrichment of the fluorinated segments on the solution surface occurred. The studies of the surface free energy, polarity, fluorine content, and morphology of the PFA films illustrated that the surface free energy and polarity of the PFA films were decreased with the augment of the FA monomer in the copolymers, and that the fluorine content and the surface roughness were increased. The surface free energy of the PFA film was as small as 16.6 mN·m−1. The surface properties of the PFA copolymers obtained by one shot feed during polymerization were superior to those obtained by continuing feed procedure. More fluorine segregation occurred and induced the formation of a fluorine-enriched surface if the PFA copolymer was postheated. The posttreatment was thus beneficial to the improvement of the surface properties of the PFA film.

Furane oligomers in plywood and wood-board production

This work overviews the synthesis of the FA monomer and other furane oligomers. It is shown, that they may be successfully used as bases for adhesive compositions in the production of heavy-duty glued woody products for domestic use.

NMR Properties of Formamide: A First Principles and Experimental Study

The tensors corresponding to the second-rank NMR observables, nuclear shielding, quadrupole coupling, and spin-spin coupling of formamide (HCONH2, FA) were determined using several first principles quantum chemical methods. The changes induced on the shielding and quadrupole coupling tensors by intermolecular hydrogen bonding were examined computationally. Liquid crystal NMR experiments were performed for dissolved FA in the SDS and CTAB lyotropic mesophases and their isotropic phases and in the gas phase. We report experimental data on shielding, quadrupole coupling, and spin-spin coupling constants. The convergence of the calculations with the basis set completeness and the treatment of electron correlation were investigated. The calculated and experimental data on the anisotropic properties of the C, N, and O shielding tensors are found to be in good agreement, given the large error limits of the latter caused by the low degree of order of FA in these systems. The medium effects on the observables are found to be readily understood by comparison of structurally relaxed FA monomer and chain trimer calculations. The calculated spin-spin coupling constants are in good agreement with the experimental ones. The anisotropic properties of the corresponding tensors are calculated to be small enough to prevent experimental detection and not to disturb structure determinations by using experimental dipolar couplings. The principal components and the orientation of the principal axis systems of each of the NMR tensors are specified.

Examination of the mechanical properties of a highly filled composite based on a furfurol acetone binder

1. Investigations were conducted to determine the critical value of the ratio of the dimensions of the core and the cross sectional area of the specimens of the highly filled composite of the polymer beton type α = 0.1. When this critical value is reached, the ultimate strength and elasticity modulus decrease. At α ⩽ 0.1, these parameters remain unchanged. 2. It has been established that the Young's moduli in tensile and compressive loading of the polymer binder based on the FA monomer are equal irrespective of the hardening conditions. 3. The results show that the preliminary loading of the polymer binder of the highfilled composite of the polymer beton type reduces the elasticity modulus of the binder.