Fluorocarbon Chains Research Articles

ChemInform Abstract: Homogeneous Catalysis, Heterogeneous Recycling: A New Family of Branched Molecules with Hydrocarbon or Fluorocarbon Chains for the Friedlaender Synthesis of Quinoline under Solvent‐Free Conditions.

ChemInform Abstract: Homogeneous Catalysis, Heterogeneous Recycling: A New Family of Branched Molecules with Hydrocarbon or Fluorocarbon Chains for the Friedlaender Synthesis of Quinoline under Solvent‐Free Conditions.

Switchable dielectric permittivity with temperature and Dc-bias in a semifluorinated azobenzene derivative

The thermodynamic, optical, structural, and dynamic properties of the semifluorinated (E)-1-(4-octylphenyl)-2-(4-(perfluorooctyl)phenyl)diazene (4) and the corresponding (E)-1,2-bis(4-octylphenyl)diazene (5) have been studied with differential scanning calorimetry, polarizing optical microscopy, X-ray diffraction, and dielectric spectroscopy. 4 combines the azobenzene properties with the fluorophobic effect and gives rise to a responsive material with a temperature and dc-bias-driven switchable dielectric permittivity within the narrower nematic phase. This is caused by the nematic potential that inevitably brings some fluorocarbon chains in proximity to the hydrocarbon chains from adjacent molecules. Frustration is alleviated by reducing the nematic-to-isotropic transition temperature and by increasing the crystalline-to-nematic transition temperature, thus limiting the stability of the nematic phase. Unlike the normal isotropic phase of compound 5, the isotropic phase of compound 4 contains dipoles with short-range orientation correlations. Optimizing the type of interactions may result in materials with applications as molecular switches and electrooptic devices.

Superhydrophobic surfaces with low and high adhesion made from mixed (hydrocarbon and fluorocarbon) 3,4-propylenedioxythiophene monomers

This work concerns new superhydrophobic surfaces, generated by replacing long fluorocarbon chains, which bioaccumulate, with short chains whilst at the same time retaining oleophobic properties. Here, is described the synthesis of novel 3,4-propylenedioxythiophene derivatives containing both a short fluorocarbon chain (perfluorobutyl) and a hydrocarbon chain of various lengths (ethyl, butyl and hexyl). Superhydrophobic (θwater > 150°) surfaces with good oleophobic properties (60° > θhexadecane > 80°) have been obtained by electrodeposition using cyclic voltammetry. Surprisingly, the lowest hystereses and sliding angles (Lotus effect) are obtained with the shortest alkyl chains due to the presence of microstructures made of nanofibers on the surfaces, whereas, the longest alkyl chains leads to nanosheets with high adhesion (Petal effect). Such materials are potential candidates for biomedical applications. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 782–788

Modification of polyurethane with novel blocking agent

Purpose – Fluorinated polyurethane combines some virtues of polyurethane and fluorinated polymer, such as low water absorption, attractive surface properties, good wearability and high weatherability. Fluorocarbon chains have been incorporated into polyurethanes by fluorinated diisocyanates, chain extenders, polyether glycols, polyester glycols and end-cappers. However, the fluorinated polyurethane, which is prepared with monohydric fluorocarbon alcohol, is seldom reported. The purpose of this research is to prepare and apply the novel fluorocarbon alcohols with side chain to modify polyurethane as the blocking agent. Design/methodology/approach – The novel fluorocarbon alcohol with side chain 2-methoxy-3-nonene perfluorinated oxygen propanol (MNPOP) can be prepared via alcoholysis reaction of methanol and 2,3-epoxypropyl perfluorinated nonene ether (EPPNE), which was prepared with etherification of hexafluoropropene trimer (HFPT) and 2,3-glycidol. Structures of EPPNE and MNPOP are confirmed with FTIR and NMR. The polyurethane can be modified when MNPOP is used as blocking agent. Findings – In comparison with the conventional polyurethane, the hydrophobic property of fluorinated polyurethane is improved. However, the increase of tensile strength of modified polyurethane is not obvious because MNPOP belongs to monohydric alcohol. And the function of MNPOP in the modified polyurethane is the blocking agent. The thermal stability of conventional and modified polyurethane is almost the same because MNPOP is de-blocked and fluorocarbon chains have not been incorporated into polyurethanes when the temperature is more than 150°C. Originality/value – The polyurethane is modified with the novel fluorocarbon alcohols with side chain, which functions as the blocking agent. The hydrophobic property of fluorinated polyurethane is improved.

Characterization of the surface modification process of Al2O3, TiO2 and ZrO2 powders by PFAS molecules

Four types of perfluoroalkylsilanes (PFAS) molecules with various lengths of fluorocarbon chains were used to modify Al2O3, TiO2 and ZrO2 powders. The surface grafting process was examined by 29Si NMR, TGA and FT-MIR techniques. Results reveal three possible types of bonding of the hydrophobic chains to the metal oxide surface. Moreover, it was established that the type of PFAS molecules and the type of modified surface have a strong influence on the mode and amount of hydrophobic molecules anchored to the surface. It was observed that alumina oxide is modified with the highest efficiency. The fraction of OH surface groups utilized during grafting of Al2O3 by C6, C8 and C10 are similar (64–68%), but for samples grafted by C12 are much lower (40%). The PFAS molecules with shorter fluorocarbon chains (C6 and C8) are attached mainly by siloxane (T3) and geminal silanol bonds (T2), whereas longer chains (C10 and C12) are attached generally by single (T1) and geminal silanol (T2) bonds. The hindrance steric effect is observed for powder samples grafted by C12 molecules.Additionally the influence of contact with water and butanol on the conformational orientation of PFAS was evaluated. It was found, that in contact with water molecules, PFAS chains are in a tangled form, whereas in contact with butanol molecules the grafted chains are straightened.

Shape Transitions in Supercritical CO2 Microemulsions Induced by Hydrotropes

The ability to induce morphological transitions in water-in-oil (w/o) and water-in-CO2 (w/c) microemulsions stabilized by a trichain anionic surfactant 1,4-bis(neopentyloxy)-3-(neopentyloxycarbonyl)-1,4-dioxobutane-2-sulfonate (TC14) with simple hydrotrope additives has been investigated. High-pressure small-angle neutron scattering (SANS) has revealed the addition of a small mole fraction of hydrotrope can yield a significant elongation in the microemulsion water droplets. For w/o systems, the degree of droplet growth was shown to be dependent on the water content, the hydrotrope mole fraction, and chemical structure, whereas for w/c microemulsions a similar, but less significant, effect was seen. The expected CO2 viscosity increase from such systems has been calculated and compared to related literature using fluorocarbon chain surfactants. This represents the first report of hydrotrope-induced morphology changes in w/c microemulsions and is a significant step forward toward the formation of hydrocarbon worm-like micellar assemblies in this industrially relevant solvent.

Elucidation of Internal Fine Structure of "Polymer Nanosphere" in the Interfacial Particle Film

Transition behavior from a monolayer on the water surface to a single particle layer of a ternary comb copolymer with highly hydrophobic carbazole units and both hydrogenated and fluorinated side-chains have been investigated by surface pressure−area (π−A) isotherm and atomic force microscopic (AFM) observation. Moreover, we fabricated a polymer nanosphere multilayered organization consisting of such polymer nanoparticles by the Langmuir–Blodgett (LB) technique, and estimated the particle arrangement by performing out-of-plane X-ray diffraction (XRD) analysis. This polymer monolayer is able to form the polymer nanosheet with amorphous layers. The multiparticle layered organization of polymer nanosphere is fabricated from the single particle layer by the LB technique. These layer structures have highly regular arrangement along the c-axis. Further, we investigated molecular arrangement inside of polymer particles by performing in-plane XRD analysis and fluorescence spectroscopy. This copolymer formed side-chain crystals inside the particles. Fluorocarbon chains had a short spacing of 5.0 A for the two-dimensional side-chain lattice whereas hydrocarbon chains formed sub-cell at short spacing of 4.2 A. In addition, aggregated structure of carbazole rings is formed by π-π interaction.

Physicochemical Properties of Oleic Acid-Based Partially Fluorinated Gemini Surfactants

We have developed oleic acid-based partially fluorinated gemini surfactants with carboxylic acid headgroups. The fluorocarbon chain is covalently bound to the terminal carbonyl group of oleic acid via a -CH(2)CH(2)OCO- unit, and the carboxylic acid headgroups are introduced to the cis double bond of oleic acid via -OCOCH(2)CH(2)- units. The aqueous solution properties of these surfactants were studied at pH 9 in the presence of 10 mmol dm–3 NaCl by means of static surface tension, pyrene fluorescence, and dynamic light scattering measurements. The resulting surface tension data demonstrate that the partially fluorinated gemini surfactants exhibit excellent surface activity in their dilute aqueous solutions. In addition, the surfactants are suggested to form micellar aggregates 2–4 nm in diameter. We also studied the aqueous temperature-concentration phase diagrams of the partially fluorinated gemini surfactants (disodium salts) on the basis of visual observations (through a crossed polarizer), polarized optical microscopy, and small angle X-ray scattering measurements. Several phase states including micellar solution phase, hexagonal phase, bicontinuous cubic phase, and lamellar phase were observed along with the coexistence of these phases in certain regions. Assemblies with lesser positive curvature tend to be formed with increasing surfactant concentration, increasing temperature, and increasing fluorocarbon chain length. A comparison of the phase diagrams of the partially fluorinated and hydrogenated surfactant systems suggests that close molecular packing is inhibited within the assemblies of the partially fluorinated surfactants because of the limited miscibility between the fluorocarbon and hydrocarbon units. To the best of our knowledge, this is the first systematic report focusing on the temperature-concentration phase diagrams of (partially) fluorinated gemini surfactants over a wide range of compositions and temperatures.

The influence of fluorocarbon chain and phosphorylcholine on the improvement of hemocompatibility: a comparative study in polyurethanes.

To study the influence of fluorinated surfaces and biomimetic surfaces on the improvement of the blood compatibility of polymers, three monomers containing a fluorinated tail and/or phosphorylcholine groups were designed and synthesized, and were then introduced into polyurethanes based on 4,4'-diphenylmethane diisocyanate (MDI), poly(tetramethylene glycol) (PTMG) and 1,4-butanediol (BDO) via end-capping. The bulk and surface characterization of the polyurethanes was carried out by dynamic mechanical analysis (DMA), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopic analysis (XPS), atomic force microscope (AFM), and water contact angle measurements. The results indicate that the fluorocarbon chains can drive the phosphorylcholine groups to aggregate at the surface of polyurethane, and the two components show spontaneous arrangement to adapt to the environment when in contact with water. The preliminary evaluation of hemocompatibility was carried out via fibrinogen adsorption and platelet adhesion. The fluorocarbon chains and phosphorylcholine groups showed a synergistic effect on the improvement of hemocompatibility.

Micellization of Zonyl FSN-100 fluorosurfactant in aqueous solutions

We report on micellization of nonionic fluorosurfactant Zonyl FSN-100 in aqueous solutions studied by means of NMR spectroscopy, light and small-angle X-ray scattering, surface tension measurements, isothermal titration calorimetry and fluorescence spectroscopy. The results allow for determination of basic parameters of Zonyl FSN-100 association like critical micellar concentration, size and association number of Zonyl FSN-100 micelles which have a core–shell structure with the core of fluorocarbon chains and the shell of oligo(ethylene oxide) chains. Time-resolved fluorescence spectroscopy studies using 1,6-diphenyl-1,3,5-hexatriene (DPH) as a fluorescent probe indicate that DPH can be solubilized in the micelles despite the general assumption about the immiscibility of hydrocarbon compounds with the fluorocarbon core of the micelles.

The influence of surface modification on the physicochemical properties of ceramic membranes

Titania ceramic membranes were efficiently modified with perfluoroalkylsilanes (PFAS). PFAS compounds with different length of fluorine alkyl chain (in the range of 6–12 carbon atoms in chain) were used during experiments. Grafting process efficiency was determined by contact angle measurements of water and glycerol. The highest hydrophobicity was obtained for the membrane grafted by C12—after 53h of modification. The contact angle value was equal to 136̊. The least efficient modification was obtained for the membrane grafted with C8, the contact angle was equal to 126̊ after 53h of grafting. The contact angle measurements with bipolar substance (glycerol) were also carried out in order to apply the Owens–Wendt method for the determination of the surface free energy (SFE) values of modified membranes. The different mode of PFAS chains attachment to the membrane surface was observed. This phenomena was related to different structure of grafting molecules. The hindrance steric effect was observed for more hydrophobic molecules (C10, C12). The surface grafting process was characterized applying 29Si NMR and TGA techniques. According to obtained results, three possible types of bonding of the hydrophobic chains to the materials surface were determined. Additionally, based on the results, it was found that type of PFAS molecule has a strong influence on the mode of anchored hydrophobic molecules to the surface. It was found that PFAS molecules with shorter fluorocarbon chains are attached mainly by siloxane (T3) and geminal silanol bonds (T2), whereas longer chains are attached mainly by single (T1) and geminal silanol (T2) bonds.

Homogeneous catalysis, heterogeneous recycling: a new family of branched molecules with hydrocarbon or fluorocarbon chains for the Friedländer synthesis of quinoline under solvent-free conditions

A new family of branched catalysts with hydrocarbon or fluorocarbon chains was used to catalyze Friedländer reaction between 2-aminoarylketones and α-methylene ketones under solvent-free conditions in good to excellent yields. The catalysts exhibit temperature-dependent solubility and such a thermomorphic character allows them to be recovered by filtration conveniently at room temperature and reused at least five times. To some extent, the branched catalysts with hydrocarbon chains are superior to those with fluorocarbon chains, as they are cheaper and more biodegradable.

Glycosyl-Nucleolipids as New Bioinspired Amphiphiles

Four new Glycosyl-NucleoLipid (GNL) analogs featuring either a single fluorocarbon or double hydrocarbon chains were synthesized in good yields from azido thymidine as starting material. Physicochemical studies (surface tension measurements, differential scanning calorimetry) indicate that hydroxybutanamide-based GNLs feature endothermic phase transition temperatures like the previously reported double chain glycerol-based GNLs. The second generation of GNFs featuring a free nucleobase reported here presents a better surface activity (lower γlim) compared to the first generation of GNFs.

Structure of Self-Assembled Monolayers of Partially Fluorinated Alkanethiols with a Fluorocarbon Part of Variable Length on Gold Substrate

A series of self-assembled monolayers (SAMs) formed on Au(111) from partially fluorinated alkanethiols (PFAT) with variable length of the fluorocarbon chain, viz. F(CF2)n(CH2)11SH (FnH11SH, n = 6, 8, and 10), was studied by high resolution X-ray photoelectron spectroscopy, infrared reflection absorption spectroscopy, and near edge X-ray absorption fine structure spectroscopy. The SAMs were found to be highly ordered and densely packed. The packing density was governed by the bulky fluorocarbon segments which adopted a helical conformation typical of this entity. With decreasing length of the fluorocarbon segment, progressive deterioration of the orientational order accompanied by a slight decrease in the packing density was observed in the fluorocarbon part of the FnH11SH SAMs. The conformation of the fluorocarbon segment was persistent through the series, with probably only a minor deterioration for n = 8 and 6. The hydrocarbon segments of the monolayers were, however, unaffected by the deterioration of the orientational order in the fluorocarbon part. They persistently exhibited all trans planar conformation, typical of densely packed assemblies of these moieties, while their orientation, given by the characteristic tilt and twist angles, mimicked that of the nonsubstituted alkanethiolate SAMs on Au(111). This behavior is explained by the effect of the bending potential which predefines the orientation of the hydrocarbon segments even if they are separated beyond the equilibrium spacing by the bulky fluorocarbon moieties.

Polyhedral vesicles with crystalline bilayers formed from catanionic surfactant mixtures of fluorocarbon and hydrocarbon amphiphiles

Salt-free catanionic mixtures of perfluorononanoic acid (C8F17COOH) and tetradecyltrimethylammonium hydroxide (TTAOH) in aqueous solution show rich and interesting self-assembly properties. With the addition of TTAOH to a C8F17COOH solution, a structural transition from polyhedral vesicles with crystalline bilayers to spherical vesicles with fluid bilayers was observed at room temperature, which was demonstrated by cryo- and FF-TEM observations, DSC and WAXS measurements. It is interesting that both uni-lamellar and multi-lamellar polyhedral vesicles were formed in these fluoro- and hydrocarbon catanionic surfactant mixtures. SAXS measurements were performed to determine the interlamellar spacing of the multi-lamellar polyhedral vesicles. The driving force for the formation of the polyhedral vesicles was the crystallization of the C8F17COO− – TTA+ ion pairs in the bilayers, which induced the excess anionic surfactants to be segregated and concentrated to produce the vertices of the polyhedral vesicles. Besides, the rheological results show that the rheological properties of the C8F17COOH/TTAOH system are greatly affected by the fluorocarbon chains due to their high rigidity and Krafft point. The solutions consisting of polyhedral vesicles have high viscoelasticity and high yield stress values while spherical vesicle solutions are not viscoelastic.

Nanostructures in Water-in-CO2 Microemulsions Stabilized by Double-Chain Fluorocarbon Solubilizers

High-pressure small-angle neutron scattering (HP-SANS) studies were conducted to investigate nanostructures and interfacial properties of water-in-supercritical CO2 (W/CO2) microemulsions with double-fluorocarbon-tail anionic surfactants, having different fluorocarbon chain lengths and linking groups (glutarate or succinate). At constant pressure and temperature, the microemulsion aqueous cores were found to swell with an increase in water-to-surfactant ratio, W0, until their solubilizing capacities were reached. Surfactants with fluorocarbon chain lengths of n = 4, 6, and 8 formed spherical reversed micelles in supercritical CO2 even at W0 over the solubilizing powers as determined by phase behavior studies, suggesting formation of Winsor-IV W/CO2 microemulsions and then Winsor-II W/CO2 microemulsions. On the other hand, a short C2 chain fluorocarbon surfactant analogue displayed a transition from Winsor-IV microemulsions to lamellar liquid crystals at W0 = 25. Critical packing parameters and aggregation numbers were calculated by using area per headgroup, shell thickness, the core/shell radii determined from SANS data analysis: these parameters were used to help understand differences in aggregation behavior and solubilizing power in CO2. Increasing the microemulsion water loading led the critical packing parameter to decrease to ~1.3 and the aggregation number to increase to >90. Although these parameters were comparable between glutarate and succinate surfactants with the same fluorocarbon chain, decreasing the fluorocarbon chain length n reduced the critical packing parameter. At the same time, reducing chain length to 2 reduced negative interfacial curvature, favoring planar structures, as demonstrated by generation of lamellar liquid crystal phases.

Thermal Behavior and High- and Low-Temperature Phase Structures of Gemini Fluorocarbon/Hydrocarbon Diblocks

The thermal behavior and phase structure of two series of gemini fluorocarbon/hydrocarbon diblock amphiphiles with the general formula (CnF2n+1CH2)(Cm-2H2m-3)CH-CH(CnF2n+1CH2)(Cm-2H2m-3), with n = 8, 10 and m = 6, 12, 14, 16, 18, 20 (abbreviated as di(FnHm)), have been investigated by differential scanning calorimetry, polarized optical and freeze-fracture transmission electron microscopies, dilatometry, and small-angle X-ray scattering (SAXS). The various terms of the series exhibit the same thermal behavior, essentially composed of two exothermal transitions, a low-temperature event that corresponds to the melting of the hydrocarbon chains at TH and a high-temperature transition associated with the melting of the fluorocarbon chains at TF. Below TH, a disordered plastic rotator phase, MLT, and above TH, a lamellar phase, MHT, were determined by SAXS experiments. Above TF, the compounds eventually clear into the isotropic liquid. In the MHT phase, both the Fn and Hm blocks are segregated from each other, forming sublayers with sharp interfaces, as revealed by the five lamellar orders and remarkable sharpness of the SAXS peaks. In the MLT phase, the partial crystallization of the aliphatic blocks when the temperature is lowered leads to the disruption of the aliphatic sublayers into rows of ribbons arranged according to pseudohexagonal and/or rectangular arrangements with different lattice sizes (p2gg symmetry). The Fn segments form the fluorinated continuum. In support of SAXS, molecular packing models of the tetrablocks are proposed on the basis of the temperature/volume variations of di(F10H20) and di(F10H16) in both high- and low-temperature phases, as determined by dilatometry. It is notable that the arrangements found for di(FnHm) are completely different from those previously reported for FnHm diblocks, revealing the influence of the linker unit on the solid-state behavior of the tetrablocks.

Interconvertible Self‐Assembly and Rheological Properties of Planar Bilayers and Vesicle Gels in Anionic/Nonionic (CF/CH) Surfactant Solutions

The surface and bulk properties of aqueous mixtures of nonionic tetraethylene glycol monododecyl ether (C12EO4) and anionic perfluorolauric acid (PFLA) were studied. These mixtures exhibited pronounced synergistic effects in terms of their mixed micellization and rheological properties. Only one type of mixed micelle is formed in dilute mixed solutions. At low PFLA content, with increasing the total surfactant concentration, short thread-like micelles grow to form larger discs. On increasing the amount of PFLA, owing to the fact that the fluctuant planar bilayers of nonionic C12EO4 become charged, vesicle gels that are comprised of densely packed unilamellar and multilamellar vesicles spontaneously form, in which the fluorocarbon chains in the bilayers are in a fluid state at room temperature. The elastic properties and the yield stress of the lamellar solutions largely increase upon the addition of small amounts of PFLA and they then pass through a maximum at a saturation of effective membrane charge density. Interestingly, increasing the pH value of the gels causes a backward transition from stiff vesicles to flexible planar bilayers. On increasing the amount of NaOH, the bilayers exhibit greater flexibility, owing to the decrease in membrane charges, along with a large decrease in the solution viscosity and their elastic properties. The combination of strong stability of the vesicle gels with the interconvertible transition of bilayers and vesicles is expected to be of practical use for controlled drug delivery and release.

Crystal Structures and Phase‐Transition Dynamics of Cobaltocenium Salts with Bis(perfluoroalkylsulfonyl)amide Anions: Remarkable Odd–Even Effect of the Fluorocarbon Chains in the Anion

Crystal structures and thermal properties of cobaltocenium salts with bis(perfluoroalkylsulfonyl)amide (C(n)F2(n+1)SO2)2N anions [n = 0 (1), 1 (1 a), 2 (1 b), 3 (1 c), and 4 (1 d)] and the 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonylamide anion (2) were investigated. In these solids, the cations are surrounded by four anions around their C5 axis, and stacking of these local structures forms two kinds of assembled structures. In the salts with even n (1, 1 b, and 1 d), the cation and anion are arranged alternately to form mixed-stack columns in the crystal. In contrast, in the salts with odd n (1 a and 1 c), the cations and anions independently form segregated-stack columns. An odd-even effect was also observed in the sum of the phase-change entropies from crystal to melt. All of the salts exhibited phase transitions in the solid state. The phase transitions to the lowest-temperature phase in 1, 1 a, and 2 are accompanied by order-disorder of the anions and symmetry lowering of the space group, which results in the formation of an ion pair. Solid-state (13)C NMR measurements on 1 a and 1 b revealed enhanced molecular motions of the cation in the higher-temperature phases.

Atmospheric pressure plasma enhanced chemical vapor deposition of hydrophobic coatings using fluorine-based liquid precursors

In this work, an atmospheric pressure plasma jet (APPJ) was investigated for developing hydrophobic thin film coatings on ultra-high molecular weight polyethylene (UHMWPE) films. Fluoroalkyl silanes, (CH3CH2O)3SiCH2CH2(CF2)7CF3 and (CH3O)3SiCH2CH2CF3 and fluoroaryl silane, F5ArSi(OCH2CH3)3 monomers with different fluorocarbon chain lengths were polymerized via plasma enhanced chemical vapor deposition (PECVD). These precursors in addition to other deposition processing conditions such as electrode-substrate gap distance and deposition time were investigated to understand the influence these parameters have on the overall deposition characteristics and hydrophobic behavior of the as-deposited thin film coatings. Attenuated total reflectance–Fourier transform infrared (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) techniques revealed that the chemical composition of the coatings retained a bulk of the monomer chemistry, signifying a low degree of fragmentation of the precursor in the plasma. This was particularly demonstrated by the coatings obtained with the fluoroaryl silane precursor, where the aromatic structure was kept intact. The hydrophobicity of the coatings was assessed using water contact angle (WCA) measurements and the thickness and morphology were examined using profilometry, scanning electron microscopy (SEM) and atomic force microscopy (AFM). Variations in the composition of fluorocarbon coatings were observed as a result of deposition conditions, however the dominant parameter was found to be the monomer precursor. Optimal hydrophobic behavior was observed from coatings derived from the monomer with the longest fluorocarbon chain, as demonstrated from trends seen in WCA and CFn group concentrations.