Surface and Thermodynamic Characterizations and Secondary

Article Cite This: J. Chem. Eng. Data XXXX, XXX, XXX−XXX

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Surface and Thermodynamic Characterizations and Secondary Transition of Novel Phthalocyanine Glass Sibel Eken KORKUT, Ozlem YAZICI, and Fatih CAKAR* Department of Chemistry, Yildiz Technical University, Davutpasa Campus, Istanbul 34220, Turkey ABSTRACT: The novel 4-(3-tert-butyl-4-hydroxyanisole)]phthalonitrile and its peripherally tetra substituted zinc phthalocyanine complex [2,9(10),16(17),23(24)tetrakis(4-(3-tert-butyl-4-hydroxyanisole) phthalocyaninato]zinc(II) (ZnPc) were synthesized and characterized by elemental and spectroscopic analysis techniques. The inverse gas chromatography (IGC) method was used to obtain secondary transition, surface properties, and thermodynamic interaction parameters of the phthalocyanine glass. Phthalocyanine selectivity was investigated using the acetate and alcohol isomers by IGC method at temperatures between 313.2 and 423.2 K. The secondary transition temperature was obtained by IGC method and differential scanning calorimetry (DSC). The dispersive component of the surface free energy, γDS , of adsorbent surface was calculated in the infinite dilution region. The specific enthalpy of adsorption, ΔHSA, the specific free energy of adsorption, ΔGSA and the specific entropy of adsorption, ΔSSA of solvents on ZnPc were determined. The acidic KA and the basic KD parameters of the ZnPc surface were calculated. The values obtained for KA and KD parameters indicated that the ZnPc surface has a basic character. The specific retention volume, V0g, Flory−Huggins interaction parameter, χ∞ * , weight fraction activity coefficient, 12, equation-of-state interaction parameter, χ12 Ω∞ 1 , and effective exchange energy parameter, Xeff of ZnPc were determined. Then, the partial molar heat of sorption, ΔH1,s and partial molar heat of mixing, ΔH∞ 1 , at infinite dilution were determined.

1. INTRODUCTION Phthalocyanines (Pcs) were known as pigment and dye agents during very long period. Pc was first discovered in 1907. Its first metal complex was synthesized in 1927. Linstead et al. published the chemistry of Pcs in a series of papers between 1934 and 1950.1 George et al. found that some of Pcs shows the glass transition temperature (Tg) in 1994.2 Today, hundreds of articles and dozens of books have been published about Pcs.3−6 The use of IGC for interactions in nonvolatile materials and characterizing structure was pioneered by Guillet et al. in the late 1960s and early 1970s.7 IGC was a popular method for examining bulk characteristics and the surface of polymers in the 1970s.8−11 IGC provides information about many important physicochemical properties such as thermodynamic interaction parameters and solubility, diffusion kinetics, surface energies, Tg values, and acid−base properties on the surface of materials.12−16 In this study, Tg and the selectivity of the phthalocyanine glass material [2,9(10),16(17),23(24)-tetrakis(4-(3-tert-butyl-4hydroxyanisole)phthalocyaninato]zinc(II) (ZnPc) were investigated by using alcohol and acetate isomers such as tert-butyl alcohol (tBAl), iso-butyl alcohol (iBAl), n-butyl alcohol (nBAl), tert-butyl acetate (tBAc), iso-butyl acetate (iBAc), and n-butyl acetate (nBAc) at temperatures between 313.2 and 423.2 K by IGC method. The IGC method was then applied to investigate the surface properties of ZnPc in relation to polar (chloroform (TCM), dichloromethane (DCM), tetrahydrofuran (THF), acetone (Ace) and ethyl acetate (EAc)) and nonpolar (n© XXXX American Chemical Society

decane (D), n-nonane (N), n-octane (O), n-heptane (Hp), and n-hexane (Hx)) solvents at temperatures in the range between 303.2 and 318.2 K and to investigate the thermodynamic interaction parameters of ZnPc in relation tridecane (TD), dodecane (DD), undecane (UD), D, N, O, Hp, iBAc, nBAc, EAc, n-propylbenzene (nPB), iso-propylbenzene (iPB), ethylbenzene (EB), chlorobenzene (ClB), and toluene (T) at temperatures between 413.2 and 463.2 K.

2. EXPERIMENTAL SECTION Electronic spectra on an Agilent 8453 UV−vis spectrophotometer and infrared spectra were recorded on a PerkinElmer Spectrum One FT-IR spectrophotometer. 1H NMR spectra were recorded on a Bruker Ultra Shield Plus 400 MHz spectrometer in CDCl3 solutions with tetramethylsilane as an internal standard. Mass spectra were measured on a Bruker Microflex LT MALDI-TOF MS and Micro TOF ESI-MS. The melting point was determined on an Electrothermal Gallenkamp apparatus. The probes were high purity grade TD, DD, UD, D, N, O, Hp, Hx, EAc, nBAc, tBAc, iBAc, nBAl, tBAl, iBAl, nPB, iPB, ClB, EB, TCM, DCM, THF, Ace, and T and were used without further purification. DSC-thermogram was recorded on a PerkinElmer DSC-7, cooling and heating rate: 10 K min−1. Chromosorb-W (AW-DMCS-treated, 80/100 Received: May 31, 2017 Accepted: March 5, 2018

A

DOI: 10.1021/acs.jced.7b00490 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

Article

The dispersive component of the surface energy γDS is described by Dorris and Gray by the following equation:

mesh) support material was supplied by Merck AG Inc. The loading percentage of the ZnPc on the support was determined as 9.16% by calcination. A Hewlett-Packard 6890N model gas chromatograph with a thermal conductivity detector was used for measurements. The column was made of stainless steel tubing with 1 m length and 0.085″ inside diameter. Trace amount of probe that was taken by Hamilton syringe as 1 μL, poured and diluted with air five times, was injected into the chromatograph at infinite dilution. ZnPc was coated on the support by evaporation of TCM as mixing the Chromosorb W in the ZnPc solution. 2.1. Synthesis of [4-(3-tert-Butyl-4-hydroxyanisole)]phthalonitrile (1). 4-Nitrophthalonitrile (0.500 g, 2.9 mmol) was dissolved in 50 mL of dry dimethylformamide (DMF), and 3-tert-butyl-4-hydroxyanisole (0.525 g, 2.9 mmol) was added. After the mixture was stirred for 30 min, finely ground anhydrous potassium carbonate (1 g, 7.2 mmol) was added in portions during 2 h with stirring. The reaction mixture was stirred under argon atmosphere at 50 °C for 48 h. The reaction mixture was cooled to room temperature and then poured into 150 mL of ice-water and stirred for 1 h. The resulting white solid was collected by filtration and washed first with water until the washings were neutral and then with Hx. Yield: 0.38 g (66%). mp: 145 °C. FT-IR: vmax, cm−1 (ATR) 3085−3030 (CH, aromatic), 2966 (CH, aliphatic), 2231 (C N), 1253, 1046 (C−O−C). 1H NMR (400 MHz, CDCl3): δ 7.72−6.77 (aromatic H, 6H), 3.83 (OCH3, 3H), 1.30 (C(CH3)3, 9H). MS (LC) m/z: Calc. 306; Found: 306 [M]+. 2.2. Synthesis of [2,9(10),16(17),23(24)-Tetrakis(4-(3tert-butyl-4-hydroxyanisole) phthalocyaninato]zinc(II) (2). A mixture of compound 1 (0.100 g, 0.335 mmol) and Zn(CH3COO)2 (0.015 g, 0.084 mmol) in n-hexanol (8 mL) was refluxed under argon atmosphere for 24 h. After it was cooled to room temperature, the crude product was precipitated with Hx. The blue product was filtered off and then washed with water. Eventually, pure ZnPc derivative was obtained by chromatography on silica gel (first with THF then with Hx:EAc (4:1) mixture as eluents). Yield 0.024 g (32%). FT-IR: vmax, cm−1 (ATR) 3080−3025 (CH, aromatic), 2960 (CH, aliphatic), 1250, 1042 (C−O−C). 1 H NMR (400 MHz, DMSO-d6): δ ppm = 8.82−7.00 (aromatic H, 24H), 3.89 (OCH3, 12H), 1.62 (C(CH3)3, 36H). MS (MALDI-TOF, DBH) (m/z): Calc 1290.82; Found: 1290 [M]+. UV−vis (TCM): λmax 684, 351.

ΔGA[CH2] = 2NAa[CH2] γSDγL[CH ]

where ΔGA[CH2] is the adsorption free energy of one methylene group, NA is Avogadro constant, a[CH2] is the cross-sectional area of an adsorbed methylene group, and γL[CH2] is the surface free energy of a solid constituted only by methylene groups such as polyethylene [γL[CH2] = 35.6 + 0.058(293.2 − T)]. The adsorption free energy of one methylene group is calculated by the following equation: ⎛ VN, n ⎞ ⎟⎟ ΔGA[CH2] = −RT ln⎜⎜ ⎝ VN, n + 1 ⎠

QJ(t R − tA )T Tf

ΔGA = −RT ln(VN) + C

(5)

where C is a constant for a given column. The dispersive component of the surface energy, γDS , can also be determined by the method given by Schultz:23 −ΔGA = RT ln(VN) = 2Na(γSD)0.5 (γLD)0.5 + C″

(6)

γDL

Here, a is the cross sectional areas of solute, is the dispersive component of the surface free energy of the solute, C″ is a constant. The specific component of the free energy of adsorption, ΔGSA, is determined from the n-alkane plot of RTln VN against a(γDL )0.5. Values of a(γDL )0.5 are found in the literature.20−22 The distance between the ordinate values of the polar probe datum point and the n-alkane reference line gives ΔGSA. An equation may be written for this procedure: ⎛ VN, n ⎞ ⎟⎟ −ΔGAS = RT ln⎜⎜ ⎝ VN,ref ⎠

(7)

Here, VN,n is the retention volume for the polar probe, and VN,ref is the retention volume for the n-alkanes reference line. By plotting ΔGSA values as a function of the reciprocal temperature 1/T, specific enthalpy of adsorption, ΔHSA and specific entropy of adsorption, ΔSSA can be calculated from the following equation: ΔGAS ΔHAS = − ΔSAS T T

(8)

ΔHSA

The values can be used to quantify acidic or the basic character of material through the equation:

(1)

−ΔHAS K DN = A + KD AN * AN *

here, T is the column temperature (K), Q is volumetric flow rate measured at room temperature Tf (K); tr is retention time of the solvent and tA is retention time of air, and J is the correction factor.17−19 Surface free energy of the adsorbent consists of two components which corresponds to the dispersive surface free energy, γDS , and the specific surface free energy, γSS. γS = γSD + γSS

(4)

Here, T is the temperature (K), R is the ideal gas constant, VN,n is the retention volume of n-alkane having n carbon atoms. The free energy of adsorption, ΔGA, is related to the net retention volume as follows:22

3. INVERSE GAS CHROMATOGRAPHY THEORY 3.1. Surface Characterization. The interaction between the probe and the ZnPc is quantified by the retention time. A net retention volume, VN, is determined as follows: VN =

(3)

2

(9)

Here, KA is Lewis acidity constant; KD is and Lewis basicity constant of a solid surface, and DN and AN* are Gutmann’s donor and modified acceptor numbers, respectively.24,25 Plotting −ΔHSA/AN* versus DN/AN* obtained a straight line with slope KA and intercept KD. If KD/KA ratio is higher than 1, the surface is considered to be basic, while if KD/KA ratio is lower than 1, the surface is considered to be acidic.

(2) B



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3.2. Thermodynamic Characterization. The fundamental information on the solute−ZnPc interactions is determined with the specific retention volume, V0g, which is decided experimentally by IGC measurements as follows.26−29 V g0 =

Q (t R − tA )J 273.2 Tf w

4. RESULTS AND DISCUSSION 4.1. Synthesis and Characterization. The synthetic route involved in the formation of the pthalocyanine complex was given in Scheme 1. A novel compound 4-(3-tert-butyl-4Scheme 1. Synthesis of Phthalocyanine 2

(10)

here, w is weight of Pc in the column. The equation-of-state interaction parameters, χ12 * , at infinitive dilution of solvent is given by the following equation: ⎛ 273.2Rv* ⎞ ⎛ p 0 (B11 − V10) V1* ⎞ χ12* = ln⎜⎜ 0 0 2 ⎟⎟ − ⎜1 − ⎟− 1 RT M 2v2* ⎠ ⎝ p1 V g V1* ⎠ ⎝ (11)

χ∞ 12,

The Flory−Huggins interaction parameters, at infinitive dilution of solvent is given by the following equation: ⎛ 273.2Rv ⎞ ⎛ p 0 (B11 − V10) V0 ⎞ χ12∞ = ln⎜⎜ 0 0 02 ⎟⎟ − ⎜1 − 1 ⎟ − 1 M 2v2 ⎠ RT ⎝ p1 V g V1 ⎠ ⎝ (12)

P01,

V01,

here, and B11 are saturated vapor pressure, molar volume of the solvent at temperature T, and gaseous state second virial coefficient, respectively, and v2 and v2* are specific volume and specific hard-core volume of the phthalocyanine, respectively. V*1 is molar hard-core volume of the solvent. The effective exchange energy parameter Xeff in the equation of state theory is defined in the eq 13: ⎡ ⎛ v 1/3 − r RTχ12* = p1* V1*⎢3T1r ln⎜⎜ 11/3 ⎢⎣ ⎝ v2r −

X ⎤ 1⎞ ⎟⎟ + v1−r 1 − v2−r1 + eff ⎥ P1*v2r ⎥⎦ 1⎠ (13)

here, p1* is characteristic pressure, v1r and v2r are reduced volume of the solvent and phthalocyanine, respectively. T1r is reduced temperature of the solvent. The weight fraction activity coefficient of solvent at infinite dilution, Ω∞ 1 , is defined by the following equation: ⎛ ⎞ p 0 (B11 − V10) 273.2R Ω1∞ = ln⎜⎜ 0 0 ⎟⎟ − 1 RT ⎝ V g p1 M1 ⎠

hydroxyanisole)]phthalonitrile 1 was prepared and used as a starting material for the preparation of peripherally tetrasubstituted phthalocyanine. Cyclotetramerization of the phthalonitrile derivative 1 to the its metal complex (2) were accomplished in n-hexanol in the presence of a catalytic amount of DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) as a strong base at reflux temperature in a glass tube. Novel phthalocyanine (2) was purified by column chromatography on silica gel and gave yields of 32% for 2. Characterization of the new phthalocyanine involves combination of methods including FT-IR, 1H NMR, and electronic and mass spectroscopy techniques. The data are consistent with the assigned structures. The IR spectra of the phthalocyanines confirmed the formation of the macrocycles. After cyclotetramerization of 1 into the ZnPc (2), the sharp peak for the CN vibration at 2231 cm−1 disappeared, respectively. In the IR spectrum of compound 2, the absorption bands at 2231 cm−1 were assigned to the CN stretching. The synthesized phthalocyanine complexes 2 showed the characteristic vibrations belonging to aromatic CH stretching at 3085 and 3025 cm−1. The 1H NMR spectra of 1 in CDCl3 was recorded. The 1H NMR spectrum of 1 showed signals ranging from 7.72 to 6.77 ppm, belonging to aromatic protons, integrating for 6 protons for 1 as expected. Also, the −OCH3 protons were observed at 3.83 ppm. In the ESI-MS spectrum of 1, we observed the [M]+ peak at values of m/z 306 amu.

(14)

here, M1 is the molecular weight of solvent. The partial molar heat of sorption, ΔH1,s, of the solvent sorbed by the phthalocyanine, is given as ⎡ ∂(ln V 0) ⎤ g ⎥ ΔH1,s = −R ⎢ ⎢⎣ ∂(1/T ) ⎥⎦

The partial molar heat of mixing, the solvent is given as ⎡ ∂(ln Ω1∞) ⎤ ΔH1∞ = R ⎢ ⎥ ⎣ ∂(1/T ) ⎦

(15)

ΔH∞ 1 ,

at infinite dilution of

(16)

Molar heat of vaporization, ΔHv, of the solvent is related to ΔH1,s and ΔH∞ 1 as follows: ΔH v = ΔH1∞ − ΔH1,s

(17) C



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1

H NMR spectrum of ZnPc (2) exhibited the aromatic protons in the range of 8.82−7.00 ppm, integrating for 24 protons for 2 as expected. Also, the −OCH3 protons were observed between 3.89 ppm. In the MALDI-TOF mass spectrum of 2, we observed the [M]+ peak at values of m/z 1290 amu. The UV−vis spectra of the new compound (2) exhibited typical spectrum of Pcs, which includes two includes two distinct bands, one of them is in the visible region at 600−700 nm (Q-band), and the other one in the UV region at about 300−500 nm (B band). This spectrum of ZnPc (2) give intense single Q bands at 684 nm and B bands at 351 nm, respectively. 4.2. Secondary Transition Temperature of the Phthalocyanine. The V0g data are essential in the determination of the secondary transition temperature of a phthalocyanine by IGC. V0g of the isomeric alcohol and acetate solvents (nBAc, tBAc, iBAc, nBAl, tBAl, and iBAl) on the ZnPc were obtained between 313.2 and 423.2 K. Retention diagrams are shown in Figure 1 for alcohols and acetates of ZnPc in terms of a plot of ln V0g calculated from eq 10 versus 1/T.

Figure 2. DSC scans of compound ZnPc during the cooling process (1) and heating process (2) (cooling and heating rates 10 °C min−1).

Figure 1. Plot of ln V0g versus 1/T for the probes: nBAl (1), iBAl (2), nBAc (3), iBAc (4), tBAl (5), and tBAc (6).

In Figure 1, Tg for ZnPc was found to be 323.2 K from the first point of deviation from linearity toward to higher temperatures in the majority of the plots. Transition thermal analysis was conducted by DSC in a PerkinElmer calorimeter, provided at cooling system. About 14.7 mg ZnPc sample was crimped an aluminum pan and heated and cooled at a rate 10 °C min−1 from 10 to 150 °C in a nitrogen atmosphere. According to DSC scans of ZnPc in Figure 2, Tg was found during the cooling process to be 323.2 K and during the heating process to be 330.75 K. Tg values obtained by DSC are in good comply with the ones obtained by IGC technique. Figure 1 shows that a good separation can be acquired between alcohol and acetate isomers in the studied temperature ranges. 4.3. Surface Characterization Results. The sorption properties of ZnPc were investigated at infinite dilution conditions by IGC between 303.2 and 318.2 K. The net retention volumes of the polar, nonpolar, and amphoteric probes on the ZnPc were obtained using eq 1. A plot of RTln VN versus 1/T for the studied solutes is drawn in Figure 3. The dispersive surface energies of ZnPc were determined by the methods proposed by Dorris and Gray as well as by Schultz

Figure 3. Plot of ln VN versus 1/T for the probes: D (1), N (2), O (3), Hp (4), Hx (5), THF (6), TCM (7), EA (8), DCM (9), and Ace (10).

the method proposed from using eqs 3 and 6, respectively, as a function of temperature. The values of the dispersive surface energies of the samples were found very close to each other regardless to the method used in the studied temperature ranges (Table 1). In this study, the specific component of the adsorption free energy ΔGSA of the polar probe on ZnPc was estimated by using eq 7, and results are given in Table 2. The plot was given as an example for ZnPc at 303.2 K (Figure 4). Table 2 shows that temperature slightly affected the ΔGSA value. The highest and the lowest ΔGSA values were observed with DCM and TCM, respectively. The specific components of the enthalpies of adsorption ΔHSA and the entropies of D



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Table 1. Dispersion Component of the Surface Free Energy, γDS with Values Calculated by Dorris−Gray and Schultz Methods for ZnPc Dorris−Gray method T (K)

γL[CH2] (mJ/m2)

ΔGA[CH2] (10 mJ/mol)

303.2 308.2 313.2 318.2

35.02 34.73 34.44 34.15

−3.15 −2.98 −2.82 −2.71

6

Schultz method γDS (mj/m2)

slope (×1024)

γDS (mj/m2)

54.27 49.03 44.09 41.28

8.85 8.38 7.91 7.62

54.00 48.39 43.16 40.07

Table 2. Variation of Free Energy of Specific Interactions, −ΔGSA (kj/mol), between ZnPc and the Polar Probes T (K)

EA

Ace

DCM

TCM

THF

303.2 308.2 313.2 318.2

4.42 4.38 4.28 4.17

8.17 8.07 8.04 8.05

10.52 10.47 10.51 10.58

3.40 3.43 3.52 3.55

4.02 3.89 3.87 3.75

Figure 5. Plot of −ΔHSA/AN* versus DN/AN*.

solvents (Hp, O, N, D, UD, DD, TD, EA, nBA, iBA, IPB, nPB, ClB, EB, and T) on ZnPc were calculated by using eq 10, and the results were given in Figure 6 with temperature between 413.2 and 463.2 K. ∞ The ZnPc−solvent interaction parameters χ12 * and χ12 determined from eqs 11 and 12 are given in Tables 4 and 5, respectively. The χ∞ 12 is higher than 0.5, which represents unfavorable ZnPc−solvent interactions; however, the values lower than 0.5

Figure 4. A plot of RTln VN vs a(γDL )0.5 for n-alkanes and polar probes on ZnPc at 303.2 K.

adsorption ΔSSA of the probes were calculated according to eq 8, and the results are given in Table 3. Table 3. Specific Enthalpy of Adsorption, ΔHSA, and Specific Entropy of Adsorption, ΔSSA, on ZnPc for the Polar Probes probe

−ΔHSA (kJ/mol)

ΔSSA × 103 (kJ/mol K)

Ace EA THF DCM TCM

10.65 9.62 9.20 9.03 0.18

0.83 1.79 1.89 −0.40 −2.06

The values of KA and KD were calculated using eq 9. A plot of −ΔHSA/AN* versus DN/AN* was drawn with KA as the slope and KD as the intercept and is shown in Figure 5. The obtained data in KA and KD are found to be 0.1024 and 0.3048, respectively. The ratio of KD/KA confirms that the surface of ZnPc is a Lewis basic character. 4.4. Thermodynamic Characterization Results. The specific retention volumes V0g are used in the determination of the physicochemical properties of a phthalocyanine by IGC method. The specific retention volumes V0g of the studied

Figure 6. Specific retention volume diagrams, V0g, of TD (1), DD (2), UD (3), D (4), N (5), O (6), Hp (7), nPB (8), ClB (9), IPB (10), EB (11), T (12), nBA (13), IBA (14), and EA (15) on ZnPc. E



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Table 4. Hard-Core Interaction Parameters (χ12 * ) of ZnPc/ Solvent Systems

Table 6. Effective Exchange Energy Parameters of the Equation of State Theory Xeff (J/cm3) of ZnPc/Solvent Systems

T (K) solvents

413.2

423.2

433.2

443.2

453.2

463.2

Hp O N D UD DD TD EB EA nBA IBA nPB IPB ClB T

2.10 2.21 2.28 2.33 2.34 2.40 2.47 1.20 1.41 1.31 1.09 1.24 1.21 0.97 1.00

2.06 2.13 2.19 2.26 2.25 2.29 2.41 1.20 1.48 1.30 1.27 1.17 1.22 1.03 1.08

2.13 2.23 2.24 2.30 2.31 2.29 2.37 1.30 1.51 1.42 1.38 1.31 1.30 1.08 1.16

2.09 2.17 2.20 2.27 2.23 2.29 2.33 1.29 1.51 1.42 1.44 1.30 1.31 1.07 1.19

2.12 2.24 2.25 2.24 2.26 2.31 2.39 1.26 1.56 1.42 1.46 1.30 1.32 1.09 1.19

2.16 2.23 2.26 2.26 2.32 2.37 2.40 1.42 1.63 1.59 1.61 1.42 1.42 1.22 1.28

T (K)

Table 5. Flory−Huggins Interaction Parameters (χ∞ 12) of ZnPc/Solvent Systems

Hp O N D UD DD TD EB EA snBA IBA nPB IPB ClB T

413.2 2.03 2.17 2.27 2.34 2.37 2.45 2.53 1.15 1.25 1.24 1.02 1.22 1.18 0.91 0.92

423.2 1.98 2.09 2.18 2.27 2.28 2.34 2.49 1.14 1.31 1.22 1.20 1.14 1.19 0.96 0.99

433.2 2.05 2.19 2.23 2.31 2.35 2.36 2.45 1.24 1.34 1.35 1.30 1.28 1.27 1.01 1.06

443.2 2.01 2.13 2.20 2.29 2.28 2.36 2.42 1.23 1.33 1.35 1.36 1.28 1.27 0.99 1.10

453.2 2.04 2.20 2.25 2.27 2.31 2.38 2.49 1.20 1.37 1.34 1.38 1.27 1.29 1.01 1.08

413.2

423.2

433.2

443.2

453.2

463.2


55.71 53.95 51.04 48.03 44.93 43.23 42.12 34.55 43.34 30.68 18.31 31.53 30.84 32.43 29.15

55.42 52.36 49.30 46.96 43.25 41.37 41.65 34.83 48.24 30.51 25.03 29.13 31.43 35.23 33.09

59.28 56.40 51.47 48.76 45.51 42.08 41.35 39.58 51.63 35.94 29.35 34.36 34.65 38.10 37.52

58.82 55.61 51.23 48.87 44.21 42.66 41.14 39.37 52.96 36.49 32.15 34.58 35.26 37.85 39.90

61.45 59.14 53.70 48.75 45.59 43.63 43.01 38.53 57.83 36.66 33.76 34.73 36.11 39.37 39.94

64.43 59.71 54.81 49.95 47.69 45.62 43.85 46.33 64.68 44.97 40.51 39.94 40.61 47.18 45.75

Table 7. Weight Fraction Activity Coefficients, Ω∞ 1 , of ZnPc/ Solvent Systems

T (K) solvents

solvents

T (K)

463.2 2.07 2.19 2.26 2.29 2.37 2.44 2.50 1.35 1.43 1.51 1.53 1.40 1.39 1.14 1.17

indicate favorable interactions in dilute ZnPc solutions. The values of the parameters χ∞ 12 and χ* 12 suggest that all the studied solvents are poor for ZnPc. The effective exchange energy parameters Xeff in the equation of state theory of studied solvents were calculated from eq 13, and results were given in Table 6. It was determined that Xeff of ZnPc in all solvents increased with temperature. The higher values of Xeff indicate poor solubility. The weight fraction activity coefficients Ω∞ 1 of the studied solvents at infinite dilution were determined from eq 14. Results are shown in Table 7. According to Guillet,10 the ∞ solvent is good if Ω∞ 1 < 5 but poor if Ω1 > 10. The values between 5 and 10 indicate moderately good solubility. The values of Ω∞ 1 found in this study suggest that ClB is good; EA, nBA, iBA, EB, iPB, nPB, and T moderately are good, and nalkanes are poor solvents for ZnPc. ΔH1,s was found from the slope of the plot of ln V0g versus 1/ T using eq 15 at the temperature range of 413.2−463.2 K, and results are given in Table 8. Table 8 shows that the sorption of the studied solvents is exothermic and heats are close each other. In the acetate and

solvents

413.2

423.2

433.2

443.2

453.2

463.2


20.60 21.79 22.18 22.11 21.46 21.75 22.18 7.04 8.42 7.47 6.37 7.28 6.93 4.59 5.89

19.82 20.14 20.30 20.62 19.45 19.42 21.00 7.03 9.02 7.39 7.61 6.77 6.99 4.83 6.34

21.30 22.09 21.22 21.42 20.72 19.50 20.10 7.77 9.37 8.37 8.46 7.73 7.55 5.07 6.86

20.35 20.94 20.48 20.93 19.18 19.47 19.36 7.67 9.34 8.39 8.98 7.72 7.60 5.02 7.11

21.03 22.48 21.56 20.30 19.73 19.76 20.50 7.46 9.84 8.33 9.23 7.69 7.70 5.14 7.05

21.82 22.12 21.69 20.61 20.82 20.89 20.72 8.71 10.62 9.92 10.69 8.68 8.51 5.85 7.75

alkane series, the sorption heats become slightly more exothermic as the number of CH2 groups increases. This implies that dispersive attractive forces take part in the sorption. ∞ ΔH∞ 1 was calculated from the slope of the plot of ln Ω1 versus 1/T in the temperature range 413.2−463.2 K using eq 16, and results are given in Table 8. ΔH∞ 1 values have positive sign for D, UD, DD, and TD that reflect endothermic mixing; however, the signs were negative for nBA, IBA, EA, nPB, IPB, EB, ClB, T, Hp, O, and N that reflect exothermic mixing.

5. CONCLUSIONS In this study, new metal-free (2) Pc which are octa-substituted with 4-((S)-3,7-dimethlyoctyloxy)phenoxy moieties at the βposition of phthalocyanine ring, were synthesized and characterized by classical spectroscopic methods (1H NMR, FT-IR, UV−vis, and mass spectroscopy). The secondary transition temperatures, surface characterization, and thermodynamic interaction parameters of the phthalocyanine glass material ZnPc were investigated by IGC method. Also, the secondary transition temperature of ZnPc was investigated by F



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Table 8. Partial Molar Heat of Sorption, ΔH1,s (kJ/mol), the Partial Molar Heat of Mixing, ΔH∞ 1 (kJ/mol), Molar Heat of Vaporization, ΔHV (kJ/mol) and Molar Heat of Vaporization, ΔHv (kJ/mol)30 solvents

ΔH1,s

ΔH∞ 1

ΔHv

ΔHv30

nBA IBA EA nPB IPB EB ClB T Hp O N D UD DD TD

10.1 11.3 7.9 10.4 10.1 9.6 9.7 9.1 7.2 8.2 8.9 9.3 10.6 11.5 12.2

−1.9 −3.5 −1.5 −1.3 −1.4 −1.3 −1.5 −1.9 −0.4 −0.4 −0.1 0.5 0.2 0.2 0.5

8.2 7.8 6.4 9.1 8.7 8.3 8.2 7.2 6.8 7.8 8.8 9.8 10.8 11.7 12.7

8.6 8.6 7.7 9.1 9.0 8.5 8.7 7.9 7.6 8.2 8.8 9.4 9.9 10.4 10.9

magnetic properties, and its utility for electrochemical sensing of ascorbic acid. Dalton Trans 2016, 45, 3086−3092. (6) Korkut, S. E.; Avciata, U.; Şener, M. K. Synthesis of nonperipherally substituted tetra(dihexylmalonate) alcohol soluble phthalocyanines. J. Coord. Chem. 2011, 64, 2936−2944. (7) Hudson, S. A.; Maitlis, P. M. Calamitic metallomesogens: metalcontaining liquid-crystals with rodlike shapes. Chem. Rev. 1993, 93, 861−885. (8) Conder, J. R.; Young, C. L. Physicochemical Measurement by Gas Chromatography; Wiley: New York, 1979. (9) Guillet, J. E. Molecular probes in the study of polymer structure. J. Macromol. Sci., Chem. 1970, 4, 1669−1674. (10) Guillet, J. E.; Romansky, M.; Price, G. J.; van der Mark, R. Studies of polymer structure and interactions by automated inverse gas chromatography. Washington, DC. Characterization of Polymers and Other Materials. American Chemical Society 1989, 391, 20−32. (11) Chen, C. T.; Al-Saigh, Z. Y. Characterization of semicrystalline polymers by inverse gas chromatography. 1. Poly(vinylidene fluoride). Macromolecules 1989, 22, 2974−2981. (12) Chehimi, M. M.; Abel, M. L.; Perruchot, C.; Delamar, M.; Lascelles, S. F.; Armes, S. P. The determination of the surface energy of conducting polymers by inverse gas chromatography at infinite dilution. Synth. Met. 1999, 104, 51−59. (13) Tihminlioglu, F.; Surana, R. K.; Danner, R. P.; Duda, J. Finite concentration inverse gas chromatography: diffusion and partition measurements. J. Polym. Sci., Part B: Polym. Phys. 1997, 35, 1279− 1290. (14) Wang, Q.; Chen, Y. L.; Zhang, Z. F.; Tang, J. Determination of Surface Characteristics of Ionic Liquid [1-Hexyl-3-methylimidazolium Hexafluorophosphate] by Inverse Gas Chromatography. J. Chem. Eng. Data 2013, 58, 2142−2146. (15) Kozłowska, M. K.; Domańska, U.; Lempert, M.; Rogalski, M. Determination of thermodynamic properties of isotactic poly (1butene) at infinite dilution using density and inverse gas chromatography. J. Chromatogr A 2005, 1068, 297−305. (16) Cakar, F.; Cankurtaran, O.; Karaman, F. Relaxation and miscibility of the blends of a poly (Ether Imide)(Ultem) and a phenola-based copolyester (Ardel) by inverse gas chromatography. Chromatographia 2012, 75, 1157−1164. (17) Conder, J. R.; Young, C. L. Physicochemical Measurement by Gas Chromatography, 1st ed.; Wiley-Interscience: New York, 1979. (18) Domanska, U.; Zolek-Tryznowska, Z. Mass Fraction Activity Coefficients at Infinite Dilution Measurements for Organic Solutes in the Dendritic Polymer PAMAM-C-12 Using Inverse Gas Chromatography. J. Chem. Eng. Data 2010, 55, 4976−4981. (19) Kiselev, A. V. Non-specific and specific interactions of molecules of different electronic structures with solid surfaces. Discuss. Faraday Soc. 1965, 40, 205−218. (20) Hamieh, T.; Schultz, J. New approach to characterise physicochemical properties of solid substrates by inverse gas chromatography at infinite dilution: I. Some new methods to determine the surface areas of some molecules adsorbed on solid surfaces. J. Chromatogr. A 2002, 969, 17−25. (21) Dorris, G. M.; Gray, D. G. Adsorption of n-alkanes at zero surface coverage on cellulose paper and wood fibres. J. Colloid Interface Sci. 1980, 77, 353−362. (22) Mukhopadhyay, P.; Schreiber, H. P. Aspects of acid-base interactions and use of inverse gas chromatography. Colloids Surf., A 1995, 100, 47−71. (23) Hamieh, T.; Schultz, J. New approach to characterise physicochemical properties of solid substrates by inverse gas chromatography at infinite dilution: II. Study of the transition temperatures of poly(methyl methacrylate) at various tacticities and of poly(methyl methacrylate) adsorbed on alumina and silica. J. Chromatogr. A 2002, 969, 27−36. (24) Santos, J.M.R.C.A.; Guthrie, J. T. Analysis of interactions in multicomponent polymeric systems: The key-role of inverse gas chromatography. Mater. Sci. Eng., R 2005, 50, 79−107.

DSC. The secondary transition temperatures of ZnPc obtained by IGC are in good agreement with the ones obtained by DSC. The study recommends that the separation ability of the ZnPc was good enough for the acetate and alcohol isomers in the studied temperature ranges. The γDS exponential values of ZnPc have different ranges from 41.28 to 54.27 mJ/m2 (Dorris−Gray approach) to 40.07−54.00 mJ/m2 (Schultz approach). γDS values from both calculation methods decrease with the increase in temperature in the range of 303.2−318.2 K. It was seen that the surface of ZnPc is basic. The IGC technique was successfully applied to determine the thermodynamic properties of ZnPc. The values of interaction parameters found in this study suggest that studied solvents are poor for ZnPc and the solubility of ZnPc in all solvents is exothermic. IGC is a convenient method for the characterization of isomer selectivity and the thermodynamic and surface properties of ZnPc.

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AUTHOR INFORMATION

Corresponding Author

*E-mail: ff[email protected]. Funding

This research project was supported by Yildiz Technical University Scientific Research Projects Coordination Department, Project 2015-01-02-GEP04. Notes

The authors declare no competing financial interest.

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REFERENCES

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Surface and Thermodynamic Characterizations and Secondary

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