Clean Synthesis of Epoxidized Tung Oil Derivatives via Phase

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Clean Synthesis of Epoxidized Tung Oil Derivatives via Phase Transfer Catalyst and Thiol-ene Reaction#A Detail Study Puyou Jia, Yufeng Ma, Haoyu Xia, Minrui Zheng, Guo dong Feng, Lihong Hu, Meng Zhang, and Yonghong Zhou ACS Sustainable Chem. Eng., Just Accepted Manuscript • DOI: 10.1021/ acssuschemeng.8b02446 • Publication Date (Web): 17 Sep 2018 Downloaded from http://pubs.acs.org on September 17, 2018

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ACS Sustainable Chemistry & Engineering

Clean Synthesis of Epoxidized Tung Oil Derivatives via Phase Transfer Catalyst and Thiol-ene Reaction：A Detail Study

Puyou Jia†, Yufeng Ma‡, Haoyu Xia§, Minrui Zheng†, Guodong Feng†, Lihong Hu†, Meng Zhang†*, Yonghong Zhou†

Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry

†

(CAF); National Engineering Lab for Biomass Chemical Utilization; Key Lab on Forest Chemical Engineering, State Forestry Administration; Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University; and Key Lab of Biomass Energy and Materials, Jiangsu Province, 16 Suojin North Road, Nanjing 210042, P. R. China. Nanjing Forestry University, College of Materials Science and Engineering, 159

‡

Longpan Road, Nanjing 210037, P. R. China Nanjing Tech University, College of Chemical Engineering, 30 Pu Zhu Road,

§

Nanjing 211800, P. R. China Corresponding Author: [email protected] (M.Z.).

*

ABSTRACT Introducing renewable tung oil into the environment-friendly plasticizer production via clean and efficient strategies to substitute toxic dioctyl phthalate (DOP) holds potential application value to reduce pollution and improve human health. Here we reported two strategies for production of epoxy plasticizers via phase transfer catalyst and thiol-ene reaction using tung oil as starting material. Phase transfer catalyst (C17H30ClN)3O40PW12·xH2O was synthesized and used in acid-free catalytic process. The optimum epoxidation reaction and thiol-ene reaction parameters were investigated. Epoxy value of the obtained epoxy tung oil methyl ester (ETM) and tung oil based epoxy plasticizer (TEP) reached 4.9 % and 5. 2%. Poly(vinyl chloride) (PVC) films plasticized with ETM and TEP showed better thermal stability and 1

ACS Paragon Plus Environment

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solvent resistance than DOP. Plasticizing efficiency of ETM and TEP reached 104.1 % and 101.5 % respectively. In conclusion, epoxy plasticizers were produced in sustainable and environmentally friendly strategies using tung oil as raw material and can completely replace toxic DOP used in flexible PVC films.

KEYWORDS: Tung oil, epoxidation, bio-plasticizer, catalysis, dioctyl phthalate

INTRODUCTION In recent years, the consumption of fossil fuels has been accelerated by population growth and economic development around the world. Fossil fuel is a non-renewable energy and its reserves are limited. It is rough estimated that the crude oil and natural gas reserves around the world will be exhausted in the near 50 years. The energy crisis will sweep across the globe if we do not find alternative and sustainable energy. In addition, large-scale use of petrochemical resources produce a large amount of waste water and residue, which directly causes the environmental pollution and human disease.1-2 For this reason, introducing renewable raw materials into the environment-friendly products production via clean and efficient ways to substitute petrochemical raw materials holds potential application value to reduce environmental pollution and mitigate the energy crisis. Tung oil is a kind of dry oi, which is extracted from the seeds of tung tree.3 China is the world’s largest producer of tung oil, it has a history of tung tree cultivation for more than 1,000 years and there are about 184 kinds of tung oil cultivars. Tung oil production in China exceeds 100,000 tons every year, which accounts 80 % of total production of tung oil in the world.4 Tung oil is also an important industrial oil, its main components is glycerol oleate, accounting for 73 - 80 % of the quality of tung oil.3,5 The chemical structure of oleic acid glycerides contains functional groups such as unsaturated bonds and ester bonds, and can undergo reactions such as epoxidation, alcoholysis, transesterification, Diels-Alder, Friedel-Frafts and amidation.6 Most of the series of products from petroleum can also be obtained from deep processing of tung oil such as epoxy resin,5,7 biodiesel,8 polyurethane foams,9 unsaturated polyester resins.10 Therefore, 2


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tung oil is a potentially sustainable raw material to produce plasticizer. Plasticizer is used to improve processability, flexibility and flame retardancy of polymers as an important additive in plastic industry. It is estimated that five million tons of plasticizer have been produced and consumed in China during the past 10 years.11 The most widely used plasticizers are phthalates, which account 80 % of plasticizer consumption in China because of the technical and economic reasons.11 However, phthalates have been restricted in the areas of toys, food packaging and medical instruments due to their productive toxicity and carcinogenesis.12 In addition, low solvent resistance and volatilization of phthalates can not keep properties of plasticized polymer products long stable. In order to reduce the toxicity of plasticizers, new alternative plasticizers were reported such as epoxidized soybean oil,13 epoxidized cardanol glycidyl ether,14 castor oil based polyol esters,15 epoxidized linseed oil,16 soybean oil based polyol ester17 and et al. These epoxidized vegetable oil plasticizers earned more attention due to good compatibility, low migration and low volatility. But there are many shortcomings for producing epoxy plasticizers using solvent method such as difficulty in solvent recovery, long production cycle, poor product quality, high cost and environmental pollution. Traditional method for production of epoxy plasticizers used formic acid, glacial acetic acid or sulphuric acid as catalyst and produced much waste water and corroded equipment. Novel strategies were developed to produce plasticized poly(vinyl chloride) (PVC) materials such as internally plasticized method.18-21 Azide functional PVC and alkynyl group-containing plasticizer monomers such as propargyl ether cardanol,18 hyperbranched polyglycerol with terminal alkyne group,19 phosphorus containing castor oil based derivatives20 and DEHP-ester21 were used to produce non-migrating PVC materials via click reaction using cuprous bromide or cuprous iodide as catalyst. Internally plasticized PVC materials were also produced via direct substitution of PVC with monomers containing mercaptan or primary amine groups.22-25 Though the internally plasticized strategies successfully produced flexible PVC materials without plasticizer migration, cuprous bromide or cuprous iodide was hard to remove during the click reaction,18-21 or plasticizing efficiency of internally plasticized way was lower than blending 3



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way.22-25 In order to produce epoxidized tung oil based plasticizers via clean and efficient ways to substitute toxic dioctyl phthalate (DOP), two strategies were designed and carried out. The first strategy is to synthesis epoxidized tung oil methyl ester using quaternary ammonium phosphotungstate as catalyst. Quaternary ammonium phosphotungstate is a kind of phase transfer catalyst with surfactant properties. The using of quaternary ammonium phosphotungstate can avoid producing waste liquid derived from inorganic acid. The second strategy is to synthesis tung oil based polyol via thiol-ene reaction, then the epoxidized tung oil based plasticizer was obtained after substitution reaction with epichlorohydrin. Thiol-ene reaction with the advantages of high yields, no byproducts, high selectivity, insensitive to water and oxygen and mild reaction conditions has been used to produce a variety of chemical products.26-29 Synthesis of epoxy tung oil derivatives by phase transfer catalysis and thiol-ene reaction follows the principles of green chemistry. This study investigated the optimum synthesis conditions of two kinds of epoxidized tung oil derivatives and their chemical structure was also characterized. Properties of PVC plasticized with epoxidized tung oil derivatives were investigated and compared with DOP. It was expected that introducing renewable tung oil into the environment-friendly plasticizer production via clean and efficient ways completely substitutes DOP.

EXPERIMENTAL SECTION Materials. Hydrogen peroxide solution(with 30% wt. of H2O2), phosphotungstic acid, sodium bicarbonate, magnesium sulfate anhydrous, dioctyl phthalate(DOP), laurylpyridinum

chloride,

trichloromethane,

methanol,

mercaptoethanol,

epichlorohydrin and 2-hydroxy-2-methylpropiophenone was purchased from Aladdin Reagent Co., Ltd. All raw materials are analytical grade and used without further purification. PVC was purchased from Hanwha. Tung oil was obtained from the Nanjing Daziran Fine chemicals Co. Ltd (≧95%, iodine value is 167). Synthesis

of

quaternary

ammonium

phosphotungstate

catalyst

((C17H30ClN)3O40PW12·xH2O). Ten grams of phosphotungstic acid, 30 g of distilled 4


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water and 60 g of hydrogen peroxide solution was mixed in a reaction bulb. The mixture was stirred at 25 ℃ for 60 min. Then trichloromethane solution containing 2.6 g of dodecylpyridinium chloride was dripped in the mixture and stirred at 25 ℃ for 60 min. Quaternary ammonium phosphotungstate catalyst was obtained after filtering, washing with deionized water and drying at 60 ℃ for 24h. Synthesis of tung oil methyl ester (TME). TME was prepared according to our previous study.30 Synthesis of epoxy tung oil methyl ester (ETM). A certain amount of TME and quaternary ammonium phosphotungstate catalyst were mixed in a round-bottom flask equipped with a thermometer and constant pressure funnel. Hydrogen peroxide solution was dripped in the mixture at 40 ℃ in 30min. The mixture was stirred at a certain temperature for some time. Then the mixture was cooled to room temperature. In this study, the epoxidation reaction parameters were optimized by controlling four variables: temperature, the mole ratio of TME and hydrogen peroxide solution, time and amount of quaternary ammonium phosphotungstate catalyst. After the reaction, catalyst was precipitation and filtration. The product was washed with 7 % sodium bicarbonate solution and distilled water. ETM was obtained after removing water via vacuum distillation. The synthesis route of the ETM was showed in Scheme 1. Synthesis of tung oil based polyol (TP). A certain amount of TME, 2-Hydroxy-2-methylpropiophenone and mercaptoethanol were dissolved in a minimum amount of acetonitrile and transferred into a quartz tube. The reaction mixture was irradiated with two 24 W lamps for some time at the atmosphere of nitrogen and room temperature. In this study, the click reaction parameters were optimized by controlling wavelength of ultraviolet radiation, time and mole ratio of 2-mercaptoethanol / double bonds. After the reaction, the product was obtained after purifying by crystallization from toluene, filtering off, washing with cold hexane and vacuum distillation. The degree of click reaction was investigated according to ASTM D4239-14 by detecting the content of elemental sulfur. Synthesis of tung oil based epoxy plasticizer (TEP). One equivalent of TP and 8 equivalent of epichlorohydrin were stirred together in the presence of 5



tetrabutylammonium chloride (1 wt % of reactants) at 75 ℃ for 4 h. The mixture was cooled down to 60 ℃. Sodium hydroxide solution (50 wt%) was dropped in the mixture and stirred at the temperature for 4 h. TEP was obtained after filtering, washing with distilled water and vacuum distillation. Preparation of flexible PVC films. Flexible PVC films were prepared according to the previous study.15,20 A certain amount of PVC, DOP, TEP and ETM was dissolved in tetrahydrofuran. The formulations of flexible PVC films were showed in the Table S1. The mixture was stirred using a magnetic stirrer at 50℃ until the solution presented transparent. Then the solution was poured into a horizontal mold with diameter of 10 cm. Flexible PVC films were obtained after drying in a constant temperature drying box at 50 ℃ for 48 h.

Scheme 1 Synthesis of epoxidized tung oil derivatives

CHARACTERIZATION Crystal structure of catalyst was characterized by X-ray diffraction (XRD) with a D8 FOCUS (BRUKER, Germany) operated at 45 kV and 40 mA using Cu-Ka radiation with a graphite diffracted beam monochromatic. The patterns were recorded in a 2-theta rang from 0º to 80º. Microstructure of catalyst was analyzed by a Hitachi 6


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3400-1 (Hitachi, Japan) scanning electron microscope instrument on gold-coated samples with an operating voltage of 15 kV. Element composition and content was obtained from energy dispersive spectrdmeter (EDS) measurements. Fourier transform infrared (FT-IR) spectra of catalyst and tung oil derivatives were investigated using a Nicolet iS10 FTIR (Nicolet Instrument Crop., USA) fourier transformed infrared spectrophotometer. FT-IR spectra were collected in the range of 4000 cm-1 to 500 cm-1. Infrared characteristic absorption peaks were annotated using OMNIC software (Thermo Electron Corporation, USA).

H Nuclear magnetic

1

resonance (NMR) of tung oil derivatives were detected on an AV-300 NMR spectrometer (Bruker Instrument Crop., Germany) at a frequency of 400 MHz. CDCl3 was used as solvent and tetrametnylsilane (TMS) was used as an internal standard in the process. MestReNova software (Santiago de Compostela, Spain) was used to handled the NMR data. Thermal stability of tung oil derivatives and flexible PVC films were anatomized using a TG209F1 TGA thermal analysis instruments (Netzsch Instrument Crop., Germany) in N2 atmosphere (50 mL/min). Thermal degradation data was collected from 40 ℃ to 600 ℃ at heating rate of 10 ℃/min. Pyrolysis gas composition of flexible PVC materials were investigated on a TG-FTIR measurements, which were carried out using a 409PC thermal analyzer (Netzsch Instrument Crop., Germany) coupled with a Nicolet iS10 FT-IR (Nicolet Instrument Crop., USA) and QMS403C instrument (Netzsch, Germany). The samples were heated from 40 ℃ to 600 ℃ at a heating rate of 10 ℃/min under N2 atmosphere. The spectra range was from 4000 cm-1 to 500 cm-1 at a resolution of 4 cm-1. Plasticizing efficiency of two kinds of tung oil derivatives was evaluated with glass transition temperature (Tg) of flexible PVC films. Tg was investigated using a DMA Q800 (TA Instruments, New Castle, DE) dynamic thermomechanical analysis (DMA) with a frequency of 1 Hz in a dual cantilever mode under N2 atmosphere. The temperature was ranged from -40 ℃ to 120 ℃ at a heating of 3 ℃/min. The mechanical properties of flexible PVC materials were detected according to GB/T 1040.1-2006 (China) at room temperature using an E43.104 Universal Testing Machine (MTS Instrument Crop., China). Epoxy value, acid value, iodine value and viscosity of epoxidized tung 7



oil

derivatives

were

determined

according

to

Chinese

Page 8 of 33

national

standard

GB/T1677-2008 (Determinating the epoxy value of plasticizers), GB/T1668-2008 (Plasticizers-Determination

of

acid

value

and

acidity),

GB/T1676-2008

(Determinating the iodine value of plasticizers) and GB/T1660-2008 (Determinating the kincmatic viscosity of plasticizers) respectively. Resistance to migration of epoxidized tung oil derivatives was studied according to ASTM D5227. A certain quality of flexible PVC films were immersed in distilled water, 10% (v/v) ethanol solution, 30% (w/v) acetic acid solution, soybean oil and petroleum ether, respectively. The test temperature was controlled at 23 ± 2 ℃ and the relative humidity was restricted at 50 ± 5 %. After 24 h, the solvent extracted PVC films were dried and reweighed. The weight loss(WL) was calculated according to the Equation (1).  W  W2  WL  ( 1 )  100 W 1  

(1)

where W1 was initial weight of flexible PVC films, and W2 was final weight of test flexible PVC films.The extraction loss data was collected using the average value of five test samples. Solubility parameter of PVC and tung oil based plasticizers were investigated according to the Small Equation (2)40,41 1/ 2

  (CED )

 E     Vi 

1/ 2



F

I

Vi



  Fi xi  F1  x2  F2  ...xn  Fn  M x1V1  x2V2  ...xnVn

D   PVC   Plasticizer

(2)

(3)

Where δ = solubility parameter, CED = cohesive energy density, Vi = molar volume, ∆E = energy of vaporization and Fi = molar attraction constant. M = molecular weight and ρ = density of the plasticizer or chain unit of PVC. D = the difference of δ between PVC and plasticzier. Flexibility of PVC films was evaluated indirectly by calculating the plasticizing efficiency of ETM and TPE based on the glass transition behaviors of PVC and PVC films plasticized with ETM and TPE. Plasticizing efficiency of ETM and TPE were calculated using the equation(4).31-33 8


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ETg (%) 

Tg , plasticizer Tg , DOP

(4)

 100

Where ETg = plasticizing efficiency of ETM or TPE, Tg = the reduction in Tg from PVC to plasticized PVC films.

RESULTS AND DISCUSSION Synthesis and characterization of quaternary ammonium phosphotungstate catalyst The obtained catalyst presented yellow powder with yield of 86.0%. Apparent structure of catalyst was showed in Fig.S1(a). Chemical structure of catalyst was investigated and compared with phosphotungstic acid. The results were showed in Fig.S1(b) and (c). Fig.S1(b) shows that characteristic absorption peak of hydroxy hydrate appeared at 3491cm-1 in the FT-IR of phosphotungstic acid. Anti-symmetrical vibration absorption peaks of P-Oa, W-Od and W-Od-W in corner shared octahedra appeared at 1073, 972 and 899 cm-1. The peaks at 806 cm-1 was corresponded to anti-symmetrical vibration absorption peaks of W-Oc-W in edge shared octahedra34,35. The results proved that the Keggin structure, as seen from Fig.S1 (f), was existed in the chemical structure of phosphotungstic acid. The peak at 3491 cm-1 in the FT-IR of catalyst disappeared, anti-symmetrical vibration absorption peaks of P-Oa, W-Od and W-Od-W in corner shared octahedra appeared at 1079, 944 and 881 cm-1, which were characteristic skeletal vibrations of Keggin oxoanions.34,35 The absorption band at 804 cm-1 was attributed to anti-symmetrical vibration absorption peaks of W-Oc-W in edge shared octahedra34,35. Shift changes of infrared characteristic absorption peak was due to the production of WOx components, which was derived from W-O-W bonds after treating by hydrogen peroxide solution. WOx components polymerized via sharing oxygen atoms in Keggin structure. In addition, new absorption bonds appeared at 2922 and 2852 cm-1 in the FT-IR spectrum, which were assigned to characteristic absorption of methyl and methylene groups. All the above results illustrated that the catalyst with Keggin structure was produced. 9



Crystal structure of the catalyst was investigated with XRD and compared with phosphotungstic acid. XRD patterns were showed in Fig.S1(d) and (e). XRD patterns of phosphotungstic acid shows typical diffraction peaks of Keggin structure at 2 theta = 17.04º, 21.44º, 26.48º, 29.68º, 33.45º, 37.68º. Characteristic diffraction peaks of Keggin structure appeared at 2 theta = 15º~20º, 20º~30º, 30º~35º in the XRD patterns of catalyst, illustrating that Keggin structure was in the chemical structure of catalyst. However, the number, angular position, relative intensity and shape of diffraction peaks were different from phosphotungstic acid, because the structure of crystalline substances of catalyst and phosphotungstic acid was different, and crystal structure of catalyst deteriorated. Element composition of catalyst was detected using EDS. Fig.S2(a) shows the EDS of catalyst, which indicated that there are four kinds of elements in catalyst, which is W, P, O and C. The relative percentage ratio is 9.67 : 0.79 : 32.93 : 39.62, which is approximately 12 : 1 : 41 : 50, illustrating that the catalyst was obtained. Microstructure of raw materials and obtained catalyst was presented in Fig.S2(b) (c) and (d). Fig.S2(b) shows microstructure of dodecylpyridinium chloride, which is granular structure of 1 - 3 μm in size. Surface of dodecylpyridinium chloride presents smooth. Microstructure of phosphotungstic acid, as seen from Fig.S2(c), shows a relatively uniform cubic crystal form 0.5 to 1 μm in size. Rock-like structure of catalyst can be observed in Fig.S2(d), because dodecylpyridinium chloride and phosphotungstic acid was attached to each other's surface and deteriorate the crystal form of catalyst. Synthesis and characterization of TME Composition and content of TME was investigated using the GC-MS measurements. The GS-MS results were showed in Fig.1 and Table 1. The results showed that content of unsaturated fatty acid methyl ester accounted 90.60 %, and content of polyunsaturated fatty acid methyl ester was 85.09 %. TME contains rich conjugated double bonds, which can be used as excellent raw materials to produce epoxy fatty acid methyl ester. The main components of TME was eleostearic acid methyl ester (75.6 %), methyl oleate (8.31 %), methyl linoleate (6.71 %), methyl 10


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palmitate (3.09 %), methyl stearate (2.47 %), methyl cis-11-eicosenoate (1.04 %), and the others account 2.78 %。 The relative molecular mass (Mr) of TME was calculated according to the following calculation formula (5): Mr = ∑ Mi×Ci

(5)

Where the Mi is the relative molecular mass of fatty acid methyl ester i, Ci is percentage of fatty acid methyl ester i. The obtained Mr of tung oil methyl ester was 284.61 g/mol.

Fig.1

GC-MS of TME

11



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Table 1 The composition and content of TME No.

1

Constitutes Methyl palmitate (C16:0)

Retention

Molecular

GC

Matched

time(min)

weight

content(%)

degree(%)

14.105

270.45

3.09

99

2

Methyl linoleate ( C18:2)

15.747

294.47

6.71

99

3

Methyl oleate (C18:1)

15.793

296.49

8.31

99

4

Methyl stearate ( C18:0)

16.010

298.5

2.47

99

17.080

292.46

75.6

99

17.555

324.54

1.04

99

-

-

2.78

-

5

Eleostearic acid methyl ester

( C18:3)

Methyl 6

cis-11-eicosenoate ( C20:1)

7

Others

Synthesis and characterization of ETM via catalysis with quaternary ammonium phosphotungstate catalyst Fig.2(a) shows the effect of temperature on epoxy value of ETM. In the experiment, the reaction time was 2.5 h, n (C=C) : n (H2O2) was 1 : 1 and the amount of catalyst was 1% of the mass of the TME. The effects of temperature on epoxy value were investigated at 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃ respectively.The results show that epoxy value of ETM increased with the rising of temperature. Epoxy value reached maximum value at 50 ℃ and decreased with the temperature rising, which illustrated that partial hydrogen peroxide hydrolysis interfered with the reaction at above 50℃. Therefore, the reaction temperature should be controlled at 50℃. Fig.2(b) shows the effect of time on epoxy value of ETM. In this experiment, the temperature was controlled at 50℃, n (C=C) : n (H2O2) were 1 : 1 and the amount of catalyst was 1% of the mass of the TME. The effect of reaction time on epoxy value was investigated at 1 h, 1.5 h, 2 h, 3 h, 4 h and 5 h respectively. The results indicated that 12


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epoxy value reached maximum value when the reaction time was 3 h, and the value changed little when the reaction time prolonged. Because water was produced with the reaction and diluted the concentration of the reactants, which was not conducive to the progress of epoxidation. Thus, the reaction time should be 3 h. Fig.2(c) shows the effect of n (H2O2) / n (TME) on epoxy value of ETM. In the experiment, the reaction time was 3 h, the amount of catalyst was 1% of the mass of the TME and the temperature was controlled at 50℃. The effect of n (H2O2) / n (TME) on epoxy value were investigated when the value was 1, 1.2, 1.4, 1.6, 1.8 and 2.0 respectively. Theoretically, excess hydrogen peroxide can promote the reaction. However, the amount of hydrogen peroxide must be controlled at an optimal amount. Fig.2(c) shows that epoxy value increases with the increase of the value of n (H2O2) / n (TME), epoxy value reached the maximum value when the value was 1.6 and changed little when the value increased, because more hydrogen peroxide diluted reactant concentration. Thus, the value of

n (H2O2 / n (TME) should be 1.6. At last, the

amount of catalyst was also examined. The results were showed in Fig.2(d). The time was controlled in 2.5 h and the temperature was 50 ℃, the value of n (C=C) : n (H2O2) was 1 : 1.6. The effects amount of catalyst on epoxy value were investigated when the amount of catalyst was 1 %, 1.5 %, 2.0 %, 2.5 %, 3.0 % and 3.5 % of the mass of TME. Epoxy value increased with the increase of catalyst content. Epoxy value reached the maximum value when the amount of catalyst was 3.0 % of the mass of the TME. Epoxy value kept unchanged when the amount of catalyst increased. The possible explanation is that excess catalyst did not participate in the reaction, because the excess catalyst can not be effectively contacted with hydrogen peroxide and TME, which can not improve catalytic efficiency. Based on the above results, the amount of catalyst should be 3.0 % of the mass of the TME. The optimal reaction conditions for preparing ETM was that the temperature, time, n (C=C) : n (H2O2) and amount of catalyst were 50 ℃, 3 h, 1 : 1.6 and 3 % of the mass of the TME. The properties of TO and ETM were showed in Table 2. The epoxy value of ETM obtained at optimal reaction conditions was 4.9 %. Catalyst was recycled and the percent recovery at the first recycle was 91.0%. A 85.6% yield of catalyst was obtained in the second recycle 13



and still showed high catalytic activity. The mechanism of epoxidation was showed in Fig.3(a). Catalyst was insoluble in the system, but it was soluble after interacting with water. Then catalyst provides active centers for epoxiation and reduces energy and reaction path for epoxidation, then accelerates the epoxidation. After the epoxidation, free state catalyst separates out and continues to the next cyclic epoxidation.

Fig.2 (a) Effect of reaction temperature on epoxy value of ETM. (b) Effect of reaction time on epoxy value of ETM. (c) Effect of n (H2O2) / n (TME) on epoxy value of ETM. (d) Effect of catalyst on epoxy value of ETM.

14


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Table 2 Properties of tung oil and tung oil derivatives

Sample

Acid value (mgKOH/g)

Iodine value (g I/100g)

Epoxy value (%)

Viscosity (25℃, mPa·s)

TO TME ETM TEP

2.37 1.86 1.62 1.61

167 153 25 24

0 0 4.9 5.2

408 45 1667 2100

Fig.3 shows the FT-IR and 1H NMR spectra of TO, TME and ETM. As seen from Fig.3(b), FT-IR spectra of TO and TME present similar absorption peaks because same chemical groups were in the chemical structure of TO and TME. The peak at 3014 cm-1 was attributed to vibration absorption of -CH=CH- groups, the peak at 738 cm-1 was corresponded to out-of-plane deformation vibration of -CH=CH-, these characteristic peaks also appeared at 3014.6 cm-1 and 738.8 cm-1 in the FT-IR spectra of TME, which illustrated that double bonds were still in chemical structure of TM after transesterification.5,7,36-38 The characteristic absorption peak of the double bonds at 3014 cm-1 disappeared in the FT-IR of ETM, and characteristic absorption peak of epoxy bonds appeared at 820.6 cm-1 and 905.5 cm-1, which indicated that double bonds were converted to epoxy groups.15,17 Fig.3(c) shows 1H NMR of TO, TME and ETM. Multiple peaks assigning to the protons of conjugated double bond appeared at 5.3 - 6.4 ppm, the protons attributing to the methyl appeared at 0.9 ppm, the signals ascribing to protons of methylene appeared at 1.2 - 1.3, 1.6, 2.0 - 2.2 and 2.4ppm.5,7,36-38 Multiple peaks ascribing to protons of conjugated double bond disappeared in the 1H NMR of ETM and new signals corresponding to protons of epoxy group appeared at around 3.1 ppm, which indicated that the double bonds were transformed to epoxy groups.15,17 Thermal stability of ETM was detected and compared with DOP. Fig.3(d) shows the TGA curves of ETM and DOP. Table S2 summarizes the TGA data including temperature at 5% mass loss(T5), temperature at 50% mass loss(T50) and char residue. The char residue for DOP and ETM is 0.12 % and 6.02 % respectively. T5 and and T50 15



for DOP and ETM is 176 ℃, 249 ℃and 212 ℃, 322 ℃ respectively, which indicated that thermal stability of ETM is more excellent than DOP. (a)

(b)

(c)

(d)

Fig.3 (a) Mechanism of epoxidation in the study. (b)1H-NMR spectra of TO,TME and ETM. (c) FT-IR spectra of TO,TME and ETM. (d) TGA curves of ETM, TEP and DOP. Synthesis and characterization of TEP via Thiol-ene reaction The effect of experimental factors including time, wavelength of UV and mole ratio of 2-marcapto-ethanol/double bond on degree of click reaction were investigated. Fig.4(a) shows the effect of time and wavelength of UV on degree of click reaction. In the experiment, the mole ratio of 2-marcapto-ethanol/double bond was 9 and the

16


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(a)

(b)

(c)

(d )

Fig.4 (a) Effect of time and wavelength of UV on degree of click reaction. (b) Mole ratio of 2-marcapto-ethanol/double bond on degree of click reaction. (c) FT-IR spectra of TEP and TP. (d) 1H NMR spectra of TEP and TP.

wavelength of UV was 360 nm. The results showed that degree of reaction increased rapidly in the first two hours and became slow in the next four hours. Then the degree of reaction kept unchanged when the reaction time was 8 h. The variation trend of the reactive degree under UV of 360 nm was similar to that when the UV was 365 nm, but the reactive degree under UV of 360 nm was higher. Therefore, the optimal synthesis conditions for production of TP should be wavelength of UV 360 nm and kept 8 h. Then the mole ratio of 2-marcapto-ethanol/double bond on degree of click reaction were investigated and showed in Fig.4(b). In the experiment, the wavelength 17



of UV was controlled at 360 nm. The results showed that degree of reaction increased rapidly with the increase of mole ratio of 2-marcapto-ethanol/double bond. The degree of reaction reached the maximum value when the mole ratio of 2-marcapto-ethanol/double bond was 12 and the reactive time was 6 h. However, the yield of TP was low. Based on the above results, the optimal synthesis conditions for production of TP were UV of 360 nm for 8 h and the mole ratio of 2-marcapto-ethanol/double bond was 9. Epoxy value of TEP was 5.2 % under the using optimal synthesis conditions. Chemical structure of TP and TPE was detected by 1H NMR and FT-IR. The 1H NMR and FT-IR spectra of TPE is presented in Fig.4 (c) and (d). Fig.4(c) shows that hydroxyl absorption peak was at 3415 cm-1 in the FT-IR of TP and double bond absorption peak disappeared at 3014 cm-1 after click reaction, the new strong peak at 1049 cm-1 was attributed to stretching vibration of C-S, which indicated that double bond of TME have been successfully converted to hydroxyl groups29. The hydroxyl absorption peak at 3415 cm-1 disappeared and absorption peak of epoxy groups appeared at 851 cm-1 in the FT-IR of TPE after epoxidation, which illustrated that hydroxyl groups have been successfully converted to epoxy groups.29 In addition, after click reaction, the peaks corresponding to conjugated double bond at 5.3 - 6.4 ppm disappeared in the 1H NMR of TP, new peaks at around 2.7 ppm and 3.7 ppm were attributed the protons of methylene connecting to hydroxyl and methylene connecting to thioether.39-40 These observation indicated that click reaction has been finished. New peaks at 2.88 ppm and 2.72 ppm were corresponded to protons of epoxy groups in 1H NMR of TPE, which indicated that TPE was successfully synthesized. Fig.5 shows the thiol-ene reaction mechanism. Firstly, the initiator is cleaved under light conditions to form free radicals, the free radical captures the hydrogen atom on the thiol radical of mercaptoethanol to produce the thiol radical.28 Then sulfhydryl free radicals attack carbon-carbon double bonds of TME, which makes the active center transfer and generates alkyl radicals. Thirdly, the alkyl radical abstracts the hydrogen atom of the thiol group on themercaptoethanol to regenerate thiol 18


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radicals and enter the cycle. At last, The thiol radicals, which were produced in the second step, participate in the synthesis of TEP or terminate with free radicals.

Fig. 5 Thiol-ene reaction mechanism in the study. Thermal stability of TEP was also detected and compared with DOP and ETM. Fig.3(d) shows the TGA curves of TEP and Table S2 summarizes the TGA data. The char residue for ETM is 7.03 %, which is more than DOP and ETM. T5 and and T50 for TEP is 214 ℃ and 330 ℃ respectively, which is higher than DOP and ETM, indicating that thermal stability of TEP is the best among DOP, ETM and TEP.

Properties of flexible PVC films plasticized with epoxidized tung oil derivatives compared with DOP Fig.6(a) and (b) shows the TGA curves of FT and FE samples. Thermal degradation of all PVC films showed two rapid thermal degradation at around 280-350℃ and 400-550℃ respectively. A large amount of hydrogen chloride was released at around 280-350℃ and complex thermal cracking compounds were produced at around 400-550 ℃.15,17,30 TGA data including T5, T50 and char residue of all PVC films were summarized in Table S3. T5 and T50 of PVC was 276.5℃ and 344.6 ℃, the value decreased from 276.5 ℃ and 344.6 ℃ to 229.4 ℃ and 317.2 ℃ with the addition of ETM, while the value for FT4 was 235.7 ℃ and 318.2 ℃, which 19



indicated that ETM and TEP reduced the thermal stability of plasticized PVC films. However, the T5 and T50 of FD were 217.1℃ and 316 ℃, which were lower than FT and FE samples, indicating that thermal stability of FD was the worst among all PVC films in the study. The char residue for FD, FT4, FE4 and PVC was 4.2 %, 5.8 %, 12.1 % and 12.8 % respectively, which illustrated that ETM and TEP produced more char residue than DOP. Based on the above results, it can be concluded that the addition of ETM and TEP reduced the thermal stability of PVC films and increased char residue. However, PVC films plasticized with TEM and ETM were more thermal stable than DOP. (a)

(b)

(c)

(d)

Fig.6(a) TGA curves of FT samples (b) TGA curves of FE samples. (c) DMA curves of FT samples.(d) DMA curves of FE samples. The miscibility and plasticizing efficiency of ETM and TEP was evaluated by Tg. In this study, Tg of all plasticized PVC films was detected and and compared with 20


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PVC and PVC/DOP system by DMA. Fig.6(c) and (d) show the DMA curves of all PVC materials. The results showed that there is only one Tg for all plasticized PVC materials, which illustrated that ETM, TEP and DOP was completely miscibility with PVC. Tg value of PVC is 82.5℃, and the value decreased with more ETM and TEP cooperating into the plasticized PVC films, which illustrated that ETM and TEP decreased some of the intermolecular forces between PVC chains. Tg for FT4, FE4 and FP was 28.6℃, 27.2℃and 29.4℃respectively when PVC blends 40 wt% of the three kinds of plasticizers, which illustrated that ETM and TEP was more efficient than DOP. Plasticizing efficiency of ETM and TEP was calculated according to the Equation (4), the results indicated that the plasticizing efficiency of ETM and TEP was 104.1 % and 101.5 % respectively, which further illustrated that plasticizing efficiency of ETM was the best among the three kinds of plasticizers. (a)

(b)

(c)

(d)

Fig.7(a) 3D FT-IR spectra of pyrolysis gas products of FP. (b) 3D FT-IR spectra of pyrolysis gas products of FE4.(c) 3D FT-IR spectra of pyrolysis gas products of FT4.(d) 3D FT-IR spectra of pyrolysis gas products of of FD. 21



Pyrolytic compounds of PVC and plasticized PVC films were tracked and investigated by TGA-FTIR, which was used to evaluate thermal degradation process of PVC films. Fig.7 shows the 3D TGA-FTIR spectra of of pyrolysis gas products of all plasticized PVC films. The pyrolysis gas products for all PVC materials are similar at around 210-350 ℃. The infrared feature absorption peak of pyrolysis gas products ascribing to CO, CO2 and C6H6 appeared at 2180, 2820 and 3085, 1540 cm-1.40-42 The strong absorption peak of pyrolysis gas products appeared at 2860 cm-1, which indicated that a large amount of HCl was released. The absorption peak at 3055 cm-1, 3085 cm-1 and 1540 cm-1 corresponding to C6H6 appeared at 176 ℃ in Fig.7(a),43-45 because DOP began pyrolysis at the temperature, and FD released more C6H6 than the other samples. Fig.7(b) and (c) shows that ester group at 1700 cm-1 released from pyrolysis of ETM and TEP due to the thermal degradation of ETM and TEP.43 Remarkably, the intensity of infrared signal of HCl of FP was stronger than FE4 and FT4 samples at around d 210-350 ℃, which illustrated that ETM and TEP played an effect of delaying the release of HCl. Tensile strength and elongation at break was used to evaluate the plasticizing efficiency of ETM and TEP. Fig.8(a) and (b) present the tensile strength and elongation at break of PVC and plasticized PVC films. The results showed that tensile strength decreased with more ETM and TEP blending with PVC. FT4, FE4 and FD contained the same amount of plasticizer, but the tensile strength was 13.4, 12.1 and 14.5 MPa. The elongation at break of PVC increased with more ETM and TEP adding in the PVC system. The elongation at break for FT4, FE4 and FD was 465, 481 and 452% respectively. The tensile strength and elongation at break proved that plasticizing efficiency of ETM and TEP was better than DOP. At the same weight ratio, ETM gave the best plasticizing efficiency. Because ETM with smaller relative molecular mass and lower branching degree than TEP and DOP was easy to insert PVC matrix and decreased the entanglement of PVC chains. Stiff PVC chains became soften when ETM inserted the PVC matrix and separated PVC chains.

22


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(a)

(b)

(c)

Fig.8 (a) Tensile strength of PVC films. (b) Elongation at break of PVC films. (c) Weight losses of extraction and volatilization tests.

The excellent solvent resistance and low volatilization can increase service life of plasticized PVC products. In this study, we characterized the weight loss of plasticized PVC materials in five different solutions and evaluated volatilization of ETM and TEP. The migration behaviour and volatilization of ETM and TEP was also compared with commercial plasticizer DOP. The results were showed in Fig.8(c). Obviously, ETM and TEP showed better solvent resistance than DOP in all solutions and air. ETM, TEP and DOP lost the most weight in petroleum ether and the least weight in distilled water among the five different solvents. FT4, FE4 and FD 23



Page 24 of 33

contained the same amount of ETM, TEP and DOP, the weight loss in distilled water, 10% (w/w) sodium hydroxide solution, 30% (w/v) acetic acid solution, olive oil oil and petroleum ether for FD was 1.2 %, 1.68 %, 1.42 %, 6.2 %, 14.3 %, but the value for FT4 and FE4 was 0.75 %, 1.42 %, 1.37 % , 4.8 %, 8.6 % and 0.45 %, 1.32 %, 1.24 %, 3.9 %, 6.9 %. Because TEP with larger molecular mass and higher branching degree than ETM and DOP was hard to migrate from PVC matrix. Solubility parameter (δ) was used to evaluate the compatibility between polymers and plasticziers. Polymers can be well dissolved in plasticizers when δ of the polymers and the plasticizers is the same or the difference is less than ± 3.07 (J/cm3)1/2.31,42 The δ value and the difference of δ between PVC and plasticzier (D) for PVC, DOP, ETM and TEP was calculated according to Equation (2) and (3), and compared in Table 3. The obtained δ of TEP and ETM is 9.49 (J/cm3)1/2 and 9.58 (J/cm3)1/2 respectively. The D value for ETM (1.20(J/cm3)1/2) was the least among ETM, TEP and DOP, which illustrated that compatibility between ETM and PVC was better than TEP and DOP. The order of compatibility was ETM>TEP> DOP, the results was consistent with previous DMA results.

Table 3 The Solubility parameter of PVC, DOP and tung oil based plasticizers Items

δ(J/cm3)1/2

D((J/cm3)1/2)

PVC

9.66

-

DOP

8.59

0.77

ETM

9.58

0.08

TEP

9.49

0.17

CONCLUSION Through the synthesis and employment of epoxy tung oil derivatives, the traditional method of synthesizing epoxy plasticizer has been upgraded. Toxic DOP can be completely substituted with the obtained epoxy tung oil derivatives in flexible PVC films. Synthesis of epoxy tung oil derivatives by phase transfer catalysis and 24


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thiol-ene reaction avoids production of waste water, which follows the principles of green

chemistry.

While,

the

obtained

phase

transfer

catalyst

(C17H30ClN)3O40PW12·xH2O can be recycled. Epoxy value of the obtained ETM and TEP reached 4.9 % and 5.2 %. PVC films plasticized with ETM and TEP showed better thermal stability and solvent resistance than DOP. Plasticizing efficiency of ETM and TEP reached 104.1 % and 101.5 % respectively. In general, this work provides sustainable and efficient strategies in the development of epoxy plasticzer. The obtained epoxy tung oil derivatives with improved properties can be widely used in PVC products to substitute toxic DOP and exhibit great potential in the plastics industry.

ASSOCIATED CONTENT The Supporting Information is available free of charge on the ACS Publications website at DOI: Fig.S1 (a) Surface structure of (C17H30ClN)3O40PW12xH2O at mm level. (b) FT-IR spetra of phosphotungstic acid. (c) FT-IR spetra of (C17H30ClN)3O40PW12xH2O. (d) XRD powder patterns of phosphotungstic acid. (e) XRD powder patterns of (C17H30ClN)3O40PW12xH2O. (f) Space structure of phosphotungstic acid. Fig.S2 (a) EDS of (C17H30ClN)3O40PW12xH2O. (b) SEM picture of dodecylpyridinium chloride. (c)

SEM

picture

of

phosphotungstic

acid.

(d)

SEM

picture

of

(C17H30ClN)3O40PW12·xH2O.Table S1 Formulations of PVC films. Table S2 TGA results of DOP, ETM and TEP. Table S3 TGA results of PVC films AUTHOR INFORMATION Corresponding Authors *E-mail: [email protected] (M.Z.).

ACKNOWLEDGEMENTS This work was supported by the Fundamental Research Funds for the Central Non-profit Research Institution of CAF(CAFYBB2018QB008), the National Natural Science Foundation of China (Grant Nos. 31700499, 31670577 and 31670578 ), and 25



Page 26 of 33

the Fundamental Research Funds from Jiangsu Province Biomass and Materials Laboratory (JSBEM-S-2017010).

REFERENCES (1) Demirbas, A. Waste management, waste resource facilities and waste conversion processes.

Energ.

Convers.

Manage.

2011,

52(2),

1280-1287.

DOI

10.1016/j.enconman.2010.09.025. (2) Kothari, R.; Tyagi, V.V.; Pathak, A. Waste-to-energy: A way from renewable energy sources to sustainable development. Renew. Sust. Energ. Rev. 2010, 14(9), 3164-3170. DOI 10.1016/j.rser.2010.05.005. (3) Meiorin, C.; Aranguren, M.I.; Mosiewicki. M.A. Polymeric networks based on tung oil: Reaction and modification with green oil monomers. Eur. Polym. J. 2015, 67, 551-560. DOI 10.1016/j.eurpolymj.2015.01.005. (4) Sharma, V.; Das, L.; Pradhan, R.C.; Naik, S.N.; Bhatnagar, N.; Kureel, R.S. Physical properties of tung seed: An industrial oil yielding crop. Ind. Crop. Prod. 2011, 33(2), 440-444. DOI 10.1016/j.indcrop.2010.10.031. (5) Huang, K.; Liu, Z.; Zhang, J.;Li, S.; Li, M.; Xia, J.; Zhou, Y. Epoxy monomers derived from tung oil fatty acids and its regulable thermosets cured in two synergistic ways. Biomacromolecules. 2014, 15, 837-843. DOI 10.1016/j.indcrop.2010.10.031. (6) Greenfield, J. Tung Oil. J. Am. Oil Chem. Soc. 1959, 36, 565-574. DOI 10.1007/BF02641151. (7) Huang, K.; Zhang, P.; Zhang, J.; Li, S.; Li, M.; Xia, J.; Zhou, Y. Preparation of biobased epoxies using tung oil fatty acid-derived C21 diacid and C22 triacid and study

of

epoxy

properties.

Gree.

Chem.

2013,

15,

2466-2475.

DOI

10.1039/C3GC40622A. (8) Chen, Y.H.; Chen, Chang, J.H.; Chang, C.C. Biodiesel production from tung (Vernicia montana) oil and its blending properties in different fatty acid compositions. Bioresource Technol. 2010, 101(24),9521-9526. DOI 10.1016/j.biortech.2010.06.117. (9) Silva, V.R.D.; Mosiewicki, M.A.; Yoshida, M.I.; Silva, M.C.D.; Stefani, P.M.; Marcovich, N.E. Polyurethane foams based on modified tung oil and reinforced with 26


Page 27 of 33 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


rice husk ash I: Synthesis and physical chemical characterization. Polym. Test. 2013, 32(2), 438-445. DOI 10.1016/j.polymertesting.2013.01.002. (10) Liu, C.; Lei, L.; Cai, Z.; Chen, J.; Hu, L.; Dai, Y.; Zhou, Y. Use of tung oil as a reactive toughening agent in dicyclopentadiene-terminated unsaturated polyester resins. Ind. Crop. Prod. 2013, 49, 412-418. DOI 10.1016/j.indcrop.2013.05.023. (11) Zheng, T.; Wu, Z.; Xie, Q.; Fang, J.; Hu, Y.; Lu, M.; Xia, F.; Nie, Y.; Ji, J. Structural modification of waste cooking oil methyl esters as cleaner plasticizer to substitute toxic dioctyl phthalate. J. Clean. Prod. 2018, 186, 1021-1030. DOI 10.1016/j.jclepro.2018.03.175. (12) Ventrice, P.; Ventrice, D.; Russo, E.; De, S. G. Phthalates: European regulation, chemistry, pharmacokinetic and related toxicity. Environ. Toxico. Phar. 2013, 36(1), 88-96. DOI 10.1016/j.etap.2013.03.014. (13) Bueno-Ferrer, C.; Garrigós, M.C.; Jiménez, A. Characterization and thermal stability of poly(vinyl chloride) plasticized with epoxidized soybean oil for food packaging.

Polym.Degrad.

2010,

Stab.

95(11),

2207-2212.

DOI

10.1016/j.polymdegradstab.2010.01.027. (14) Chen, J.; Liu, Z. S.; Jiang, J. C.; Nie, X. A.; Zhou, Y. H.; Murray, R. E. A novel biobased plasticizer of epoxidized cardanol glycidyl ether: synthesis and application in soft poly(vinyl chloride) films. RSC Adv. 2015, 5, 56171-56180. DOI 10.1039/C5RA07096A. (15) Jia, P.; Zhang, M.; Hu, L.; Feng, G.; Bo, C.; Zhou, Y. Synthesis and application of environmental castor oil based polyol ester plasticizers for poly(vinyl chloride). ACS

Sustainable

Chem.

Eng.,

2015,

3

(9),

2187-2193.

DOI

10.1021/acssuschemeng.5b00449. (16) Fenollar, O.;

Garcia-Sanoguera, D.; Sanchez-Nacher, L.; Lopez, J.; Balart, R.

Effect of the epoxidized linseed oil concentration as natural plasticizer in vinyl plastisols. J. Mater. Sci. 2010, 45(16), 4406-4413. DOI 10.1007/s10853-010-4520-6. (17) Jia, P.; Zhang, M.; Hu, L.; Zhou, Y. Green plasticizers derived from soybean oil for poly(vinyl chloride) as a renewable resource material. Korean J. Chem. Eng. 2016, 33(3), 1080-1087. DOI 10.1007/s11814-015-0213-9. 27



Page 28 of 33

(18) Jia, P.; Zhang, M.; Hu, L.; Wang, R.; Sun, C.; Zhou, Y. Cardanol groups grafted on poly(vinyl chloride)-synthesis, performance and plasticization mechanism. Polymers. 2017, 9(11), 621. DOI 10.3390/polym9110621. (19) Lee, K. W.;

Chung, J. W.; Kwak, S. Structurally enhanced self-plasticization of

poly(vinyl chloride) via click grafting of hyperbranched polyglycerol. Macromol. Rapid Comm. 2016, 37(24), 2045-2051. DOI 10.1002/marc.201600533. (20) Jia, P.; Hu, L.; Zhang, M.; Feng, G.; Zhou, Y. Phosphorus containing castor oil based derivatives: Potential non-migratory flame retardant plasticizer. Eur. Polym. J. 2017, 87, 209-220. DOI 10.1016/j.eurpolymj.2016.12.023. (21) Earla, A.; Li, L.; Costanzo, P.; Braslau, R. Phthalate plasticizers covalently linked to PVC via copper-free or copper catalyzed azide-alkyne cycloadditions. Polymer. 2017, 109(27), 1-12. DOI 10.1016/j.polymer.2016.12.014. (22) Jia, P.; Zhang, M.; Hu, L.; Song, F.; Feng, G.; Zhou, Y. A strategy for nonmigrating plasticized PVC modified with mannich base of waste cooking oil methyl ester. Sci. Rep-UK. 2018, 8, 1589. DOI 10.1038/s41598-018-19958-y. (23) Jia, P.; Hu, L.; Shang, Q.; Wang, R.; Zhang, M.; Zhou, Y. Self-plasticization of PVC materials via chemical modification of mannich base of cardanol butyl ether. ACS

Sustainable

Chem.

Eng.

2017,

5

(8),

6665-6673.

DOI

10.1021/acssuschemeng.7b00900. (24) Navarro, R.; Perrino, M. P.; García, C.; Elvira, C.; Gallardo, A.; Reinecke, H. Highly flexible PVC materials without plasticizer migration as obtained by efficient one-pot procedure using trichlorotriazine chemistry. Macromolecules, 2016, 49(6), 2224-2227. DOI 10.1021/acs.macromol.6b00214. (25) Navarro, R.; Bierbrauer, K.; Mijangos, C.; Goiti, E.; Reinecke, H. Modification of poly(vinyl chloride) with new aromatic thiol compounds. Synthesis and characterization.

Polym.

Degrad.

Stab.

2008,

93(3),

585-591.

DOI

10.1016/j.polymdegradstab.2008.01.015. (26) Mane, S. R.; Sarkar, S.; Rao N, V.; Sathyan, A.; Shunmugam, R. An efficient method to prepare a new class of regioregular graft copolymer via a click chemistry approach. RSC Adv. 2015, 5, 74159-74161. DOI 10.1039/C5RA12510C. 28


Page 29 of 33 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(27) Hoyle, C. E.; Bowman, C. N. Thiol-ene click chemistry. Angew. Chem. Int. Ed. 2010, 49, 1540-1573. DOI 10.1002/anie.200903924. (28) Fairbanks, B.D.; Scott, T.F.; Kloxin, C.J.; Anseth,K.S.; Bowman, C.N. Thiol-Yne photopolymerizations: novel mechanism, kinetics, and step-growth formation of highly

cross-linked

networks.

Macromolecules.

2009,

42,

211-217.

DOI

10.1021/ma801903w. (29) Yao, L.; Chen, Q.; Xu,W.; Ye, Z.; Shen, Z.; Chen, M. Preparation of cardanol based epoxy plasticizer by click chemistry and its action on poly(vinyl chloride). J. Appl. Polym. Sci. 2017, 134(23). DOI 10.1002/app.44890. (30) Jia, P.; Hu, L.; Yang, X.; Zhang, M.; Shang, Q.; Zhou, Y. Internally plasticized PVC materials via covalent attachment of aminated tung oil methyl ester. RSC Adv., 2017, 7, 30101-30108. DOI 10.1039/C7RA04386D. (31) Choi, J.; Kwak, S. Y. Hyperbranched poly(ε-caprolactone) as a nonmigrating alternative plasticizer for phthalates in flexible PVC. Environ. Sci. Technol. 2007, 41, 3763-3768. DOI 10.1021/es062715t. (32) Yu, B. Y.; Chung, J. W.; Kwak, S. Y. Reduced migration from flexible poly(vinyl chloride) of a plasticizer containing β-cyclodextrin derivative. Environ. Sci. Technol. 2008, 42, 7522-7527. DOI 10.1021/es800895x. (33) Woohyuk,

C.;

Jae,

W.;

Seung,

Y.

K.

Unentangled

star-shape

poly(ε-caprolactone)s as phthalate-free PVC plasticizers designed for non-toxicity and improved migration resistance. ACS Appl. Mater. Interfaces. 2014, 6, 11118-11128. DOI 10.1021/am500740v. (34) Song, S.; Shen, S.; Cui, X.; Yao, D.; Hu, D. Microhydrogel surface-supported quaternary ammonium peroxotungstophosphate as reusable catalytic materials for oxidation

of

DBT.

React.

Funct.

Polym.

2011,

71,

512-519.

DOI

10.1016/j.reactfunctpolym.2011.01.003. (35) Chen,

Y.;

Guo,

J.;

Kim,

H.

Preparation

of

poly(vinylidene

fluoride)/phosphotungstic acid composite nanofiber membranes by electrospinning for proton conductivity. React. Funct. Polym. 2010, 70(1), 69-74. DOI 10.1016/j.reactfunctpolym.2009.10.006. 29



(36) Lacerda, T.M.; Carvalho, A.;

Gandini, A. Two alternative approaches to the

Diels-Alder polymerization of tung oil. RSC Adv. 2014, 4, 26829-26837. DOI 10.1039/C4RA03416C. (37) Yang, X.; Li, S.; Xia, J.; Song, J.;Huang, K.; Li, M. Novel renewable resource-based UV-curable copolymers derived from myrcene and tung oil: Preparation, characterization and properties. Ind. Crops Prod. 2015, 63, 17-25. DOI 10.1016/j.indcrop.2014.10.024. (38) Meiorin, C.; Aranguren, M.I.; Mosiewicki, M.A. Nanocomposites with superparamagnetic behavior based on a vegetable oil and magnetite nanoparticles. Eur. Polym. J. 2015, 67, 551-560. DOI 10.1016/j.eurpolymj.2014.01.018. (39) Desroches, M.; Caillol, S.; Lapinte, V.; Auvergane, R.; Boutevin, B. Synthesis of biobased polyols by thiol−ene coupling from vegetable oils. Macromolecules. 2011, 44(8), 2489-2500. DOI 10.1021/ma102884w. (40) Omrani, I.; Farhadian, A.; Babanejad, N.; HShendi, H.K.; Ahmadi, A.; Nabid, M.R. Synthesis of novel high primary hydroxyl functionality polyol from sunflower oil using thiol-yne reaction and their application in polyurethane coating. Eur. Polym. J. 2016, 82, 220-231. 10.1016/j.eurpolymj.2016.07.021. (41) Qu, H.; Liu, X.; Xu, J.; Ma, H.; Jiao, Y.; Xie, J. Investigation on thermal degradation of poly(1,4-butylene terephthalate) filled with aluminum hypophosphite and trimer by thermogravimetric analysis-fourier transform infrared spectroscopy and thermogravimetric analysis-mass spectrometry. Ind. Eng. Chem. Res. 2014, 53(20), 8476-8483. DOI 10.1021/ie404297r. (42) Chen, J.; Wang, Y.; Huang, J.; Li, K.; Nie, X. Synthesis of tung oil based triglycidyl ester plasticizer andmits effects on poly(vinyl chloride) soft films. ACS Sustainable Chem. Eng., 2017, 6(1). DOI 10.1021/acssuschemeng.7b02989. (43) Jia, P.; Zhang, M.; Liu, C.; Hu, L.; Feng, F.; Bo, C.; Zhou, Y. Effect of chlorinated phosphate ester based on castor oil on thermal degradation of poly (vinyl chloride) blends and its flame retardant mechanism as secondary plasticizer. RSC Adv. 2015, 5, 41169-41178. DOI 10.1039/C5RA05784A. (44) Chen, J.; Liu, S.; Zhao, J. Synthesis, application and flame retardancy 30


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mechanism of a novel flame retardant containing silicon and caged bicyclic phosphate for

polyamide

6.

Polym.

Degrad.

Stabil.

2011,

96,

1508-1515.

DOI

10.1016/j.polymdegradstab.2011.05.002. (45) Song, S.; Ma, J.; Cao, K.; Chang, G.; Huang, Y.; Yang, J. Synthesis of a novel dicyclic silicon-/phosphorus hybrid and its performance on flame retardancy of epoxy resin.

Polym.

Degrad.

Stabil.

2014,

10.1016/j.polymdegradstab.2013.12.013.

31


99,

43-52.

DOI


For Table of Contents Use Only

Epoxidized tung oil derivatives were synthesized via phase transfer catalyst and thiol-ene reaction to replace DOP as PVC plasticizer.

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Graphic for manuscript 253x82mm (300 x 300 DPI)


Clean Synthesis of Epoxidized Tung Oil Derivatives via Phase

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