WO2013003225A2

WO2013003225A2 - Vegetable-oil derived plasticizer

Info

Publication number: WO2013003225A2
Application number: PCT/US2012/043740
Authority: WO
Inventors: Abhuijit GHOSH-DASTIDAR; Robert F. Eaton; Antoni Adamczyk; Bruce M. Bell; Robert M. Campbell
Original assignee: Dow Global Technologies Llc
Priority date: 2011-06-29
Filing date: 2012-06-22
Publication date: 2013-01-03
Also published as: TW201305100A; WO2013003225A3

Abstract

Green plasticizers are made by a process comprising the steps, in any order, of epoxidizing and transesterifying a natural oil, e.g., corn, sunflower, etc., having (1) an iodine number (IV) of 60 or more, and (2) a linolenic acid content of 5 weight percent (wt%) or less based on the weight of the oil.

Description

VEGETABLE-OIL DERIVED PLASTICIZER

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0001] This invention relates to plasticizers. In one aspect the invention relates to green plasticizers derived from natural oils, i.e., oils derived from biological sources, while in another aspect, the invention relates to a process of producing such plasticizers.

2. Description of the Related Art

[0002] Soybean oil triglyceride typically is comprised of approximately 15 weight percent (wt%) saturated and 85 wt% unsaturated fatty acids. Among the unsaturated fatty acids, about 24 wt% is from monounsaturated oleic acid, about 54 wt% from di-unsaturated linoleic acid, and the rest, around 7 wt% is from polyunsaturated linolenic acid. Epoxidized methyl ester of soybean oil (soy-eFAME) can be used as the sole plasticizer for polyvinyl chloride (PVC) and other polymers (natural rubber, acrylate, etc.) or alternately, it can be used as a primary or secondary plasticizer in a plasticizer blend such as with epoxidized soybean oil (ESO). eFAME often contains various impurities generated from degradation of epoxy rings. The major share of these impurities come from epoxy ring degradation in the methyl epoxy linolenate chains with a smaller fraction coming from epoxy ring degradation in the methyl epoxy linoleate fraction. The main degradation products are generated from ring-opening of the epoxy group, producing two hydroxyl groups or one hydroxyl group and another carboxylic group in its place.

[0003] In some cases, two out of three epoxy rings in the methyl linolenate chain open up. In general, these hydroxyl-epoxides are more hydrophilic than the original epoxy methyl esters, and hence they leach out more preferentially in contact with water. In potential food and medical applications, where the medium is aqueous or contains a significant amount of water, these impurities will leach out more into the food or in the specific substrates of interest than the overall plasticizer content.

[0004] Since epoxy methyl linolenate produces the most hydrophilic degradation compounds, which in turn has the highest potential to leach out in contact with aqueous or semi-aqueous media, an interest exists for plasticizers derived from natural oils that minimize this component of their composition. [0005] Moreover, the impurity profile for soy-eFAME varies by the process from which it is made. The current commercial route for making soy-eFAME plasticizer is first transesterifying soybean oil to make fatty acid methyl ester (FAME) and then epoxidizing it to make eFAME. eFAME made from this route shows a concentration of hydroxyl-epoxides in the linolenate chains. An interest exists in a process for producing eFAME in which this concentration of hydroxyl-epoxides in the linolenate chains is minimized.

SUMMARY OF THE INVENTION

[0006] In one embodiment, the invention is a green plasticizer that is made by epoxidation and transesterification (or transesterification followed by epoxidation) of natural oil (e.g., oils derived from biological sources such as vegetables, seeds, fish, animal fat, etc., as opposed to oils derived from petroleum or other mineral sources) which has a very low level of linolenic acid in its fatty acid distribution. An iodine number (IV) of greater than (>) 60, or preferably >80 or more preferably >100, is desired since the presence of unsaturation is necessary to incorporate oxirane oxygen on the fatty acid chain, which in turn enhances compatibility with a plastic, e.g., PVC, matrix. Table 1A reports several examples of natural oil feedstocks that have >95 IV with very low linolenic acid content (typically less than (<) 5 weight percent (wt%), or more typically <3 wt%, or even typically <2 wt%) based on the weight of the oil.

TABLE 1A

Natural Oil with High IV and Low Linolenic Acid Content

[0007] Table IB reports several examples of natural oil feedstocks that have >80 IV with very low linolenic content and that can also be used as the feedstock for a green plasticizer suitable for medical or food use. TABLE IB

Natural Oil with Medium IV and Low Linolenic Acid Content

[0008] In one embodiment the invention is a green plasticizer system, or green plasticizer blend, suitable for use in food and medical applications, the plasticizer system or blend made by the transesterification of epoxidized natural oil, e.g., ESO, rather than by the epoxidation of transesterified natural oil, e.g., FAME. Table 2 shows those natural oils with high iodine number and high linolenic acid content which are epoxidized first and transesterified second to have a low hydrophilic impurity value as measured by electrospray ionization/liquid chromatography/mass spectrometry (ESI/LC/MS).

TABLE 2

Natural Oil with High IV and High Linolenic Acid Content

[0009] In one embodiment the invention is a process for making a green plasticizer, the process comprising the steps, in any order, of epoxidizing and transesterifying a natural oil having (1) an IV of 60 or more, and (2) a linolenic acid content of 5 wt% or less based on the weight of the oil.

[0010] In one embodiment the invention is a process for making a green plasticizer, the process comprising the steps of epoxidizing natural oil with (1) an iodine number (IV) of 60 or more, and (2) a linolenic acid content of 5 wt% or more based on the weight of the oil, and then transesterifying the epoxidized oil to make an epoxidized fatty acid alkyl ester. In one embodiment the process comprises the further step of blending the transesterified epoxidized fatty acid alkyl ester, e.g., eFAME, with epoxidized natural oil that has not been transesterified, e.g., ESO. The weight ratio of epoxidized natural oil, e.g., ESO, to transesterified epoxidized natural oil, e.g., e-FAME, can vary widely and is tailored to the requirements of the intended application of the plasticizer.

[0011] In one embodiment the invention is a green plasticizer made by any of the processes of the previous embodiments.

[0012] In one embodiment the invention is a green plasticizer comprising at least one of eFAME and a non-soy based fatty acid methyl ester, e.g., corn or sunflower oil based eFAME, that has a hydrophilic extractable content of less than two percent (as area percent) as determined by ESI/LC/MS and high pressure liquid chromatograph - evaporative light scattering detection (HPLC-ELSD).

[0013] The conditions of the epoxidation and transesterification reactions are well known in the art and can vary to convenience.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Definitions

[0014] Unless stated to the contrary, implicit from the context, or customary in the art, all parts and percents are based on weight and all test methods are current as of the filing date of this disclosure. For purposes of United States patent practice, the contents of any referenced patent, patent application or publication are incorporated by reference in their entirety (or its equivalent US version is so incorporated by reference) especially with respect to the disclosure of definitions (to the extent not inconsistent with any definitions specifically provided in this disclosure) and general knowledge in the art.

[0015] The numerical ranges in this disclosure are approximate, and thus may include values outside of the range unless otherwise indicated. Numerical ranges include all values from and including the lower and the upper values, in increments of one unit, provided that there is a separation of at least two units between any lower value and any higher value. As an example, if a compositional, physical or other property, such as, for example, molecular weight, etc., is from 100 to 1,000, then all individual values, such as 100, 101, 102, etc., and sub ranges, such as 100 to 144, 155 to 170, 197 to 200, etc., are expressly enumerated. For ranges containing values which are less than one or containing fractional numbers greater than one (e.g., 1.1 , 1.5, etc.), one unit is considered to be 0.0001, 0.001, 0.01 or 0.1, as appropriate. For ranges containing single digit numbers less than ten (e.g., 1 to 5), one unit is typically considered to be 0.1. These are only examples of what is specifically intended, and all possible combinations of numerical values between the lowest value and the highest value enumerated, are to be considered to be expressly stated in this disclosure. Numerical ranges are provided within this disclosure for, among other things, the blend weight ratio of epoxidized natural oil, e.g., ESO, and transesterified epoxidized natural oil, e.g., e-FAME.

[0016] "Natural oil" and like terms mean an oil derived from one or more biological sources, e.g., seeds, vegetables, fish, animal fats, bacteria, algae, etc., as opposed to an oil derived from petroleum or other mineral source.

[0017] "Epoxidation" and like terms mean a process of forming an epoxide, also known as an oxirane or alkylene oxide. An epoxide is a three-membered cyclic ether in which an oxygen atom is joined to each of two carbon atoms that are already bonded to each other.

[0018] "Fatty acid" and like terms mean a monocarboxylic acid composed of an aliphatic chain typically containing 4 to 22 carbon atoms with a terminal carboxyl group (-COOH). The fatty acid can be saturated or unsaturated, branched or unbranched, and may or may not include one or more hydroxyl group(s).

[0019] "Epoxidized fatty acid ester" and like terms mean a compound with at least one fatty acid moiety which contains at least one epoxide group.

[0020] "Transesterification" and like terms mean a process of exchanging the organic group R" of an ester with the organic group R' of an alcohol, i.e.,

R'OH + RCOOR" R"OH + RCOOR'

[0021] "Green plasticizer" and like terms mean a compound derived from natural oil that increases the plasticity or flexibility of a plastic to which it is added.

[0022] "Green plasticizer blend" and like terms mean a mixture comprising a green plasticizer with one or more other compounds, particularly another green plasticizer. In one embodiment, a green plasticizer blend comprises an epoxidized fatty acid ester derived from natural oil and that has not been subjected to transesterification, e.g., ESO, and an epoxidized fatty acid ester derived from natural oil and that has been subjected to transesterification, e.g., e-FAME.

Natural Oils

[0023] Typical natural oils useful in the practice of this invention include, but are not limited to, oils derived from animal and vegetable sources, such as corn, sunflower, cotton seed, safflower, olive, palm, linseed, canola, rapeseed, soy, rung, fish, beef tallow, bacteria, algae and the like. In one embodiment, the natural oils used in the practice of this invention typically have both an IV (as measured by AOCS Tg 1-64) over 60, more typically over 80 and even more typically over 100, and a linolenic acid content of typically <5 wt%, more typically <3 wt%, and even typically <2 wt% based on the weight of the oil.

Epoxidation of the Natural Oil

[0024] As a nonlimiting example, a solution of peracid, e.g., peracetic acid in ethyl acetate is used to epoxidize the double bonds of the fatty acids in the natural oil. In an embodiment, the per-acid is kept below 35 wt % based on the solution weight and the temperature is kept below 35°C. After completion, the ethyl acetate and byproduct acetic acid are removed by vacuum stripping. The general reaction conditions are well known and can vary to convenience. In one embodiment, the epoxidation is conducted in such a manner that oxirane oxygen level in the final product is above 6.5 wt% based on final product weight.

[0025] Nonlimiting examples of suitable epoxidized fatty acid esters that can be used in the practice of this invention include epoxidized animal and vegetable oils, such as epoxidized naturally occurring oils like epoxidized soybean oil (ESO), epoxidized corn oil, epoxidized sunflower oil, epoxidized palm oil, epoxidized linseed oil, epoxidized canola oil, epoxidized rapeseed oil, epoxidized safflower oil, epoxidized tall oil, epoxidized tung oil, epoxidized fish oil, epoxidized beef tallow oil, epoxidized castor oil, etc., and various epoxidized esters such as epoxidized propylene glycol dioleate, epoxidized methyl stearate, epoxidized butyl stearate, epoxidized 2-ethylhexyl stearate, epoxidized stearyl stearate, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate epoxidized soybean oil, epoxidized derivatives of each of the foregoing, and any combination of the foregoing. In one embodiment, naturally occurring epoxidized oil, e.g., Vernonia oil, can be used in place of the first step of the inventive process for making an epoxidized alkyl ester of a natural oil.

Alcohols

[0026] The alcohols that can be used in the practice of this invention include, but are not limited to, primary and secondary alcohols, such as alkanols of 1 to 18 carbon atoms, e.g., methanol, n-propanol, isopropanol, n-butanol, sec-butanol, isobiitanol, pentanol, hexanol, 2-ethylhexanol, tridecanol, stearyl alcohol, etc.; cycloalkanols of 5 to 12 carbon atoms, e.g., cyclohexanol, cycloheptanol, etc.; aralkanols of 7 to 40 carbon atoms, e.g., benzyl alcohol, 2-phenyl ethanol, etc.; polyhydric alcohols of 2 to about 15 carbon atoms, e.g., ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, hexamethylene glycol, decamethylene glycol, 1 ,12-dihydroxyoctadecane, glycerol, etc.; polymeric polyhydric alcohols, e.g., polyvinyl alcohol; glycol ethers and polyalkylene glycol ethers, e.g., methyl glycol, ethyl glycol, butyl glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, higher polyethylene glycols, dipropylene glycol, tripropylene glycol, polypropylene glycol ether, polybutylene glycol ether, etc. Other suitable hydroxyl- containing compounds are disclosed in USP 3,347,926, 3,654,370 and 4,014,933.

Transesterification

[0027] The transesterification of the epoxidized fatty acid (natural oil) employs equipment and conditions well known in the art. The epoxidized fatty acid and alcohol are contacted with one another under transesterification conditions with either an acid or base catalyst. In one embodiment, soy oil is transesterified with methanol to make the methyl ester of the fatty acids in the oil. Glycerol is removed from the reaction products due to insolubility. In one embodiment the epoxidized fatty acid ester can be any epoxidized fatty acid Ci-C)₄ ester, including methyl, ethyl, propyl, butyl, and 2-ethylhexyl esters. In one embodiment the epoxidized fatty acid ester is an epoxide of a fatty acid methyl ester. In one embodiment the epoxidized fatty acid is ESO and its transesterified derivative is eFAME. In one embodiment the eFAME is washed with water in one or multiple stages to reduce or eliminate unwanted byproducts.

Green Plasticizer Blend

[0028] The green plasticizer blend or system of this invention comprises a mixture of an epoxidized fatty acid ester derived from natural oil and that has not been subjected to transesterification, and an epoxidized fatty acid ester derived from natural oil and that has been subjected to transesterification. The epoxidized natural oil that has not been subjected to transesterification and the transesterified epoxidized natural oil are blended with one another under any suitable conditions using known equipment and techniques to form a homogeneous or substantially homogeneous blend. The relative amounts in weight percent of each component of the blend can vary widely, but typically the weight ratio of rion- transesterified epoxidized fatty acid ester to transesterified epoxidized fatty acid ester is greater than (>) 0 : less than (<) 100 to <100 : >0, more typically from 10:90 to 90: 10, more typically from 20:80 to 80:20 and even more typically from 30:70 to 70:30. The green plasticizer blend can contain one or more additives, e.g., anti-oxidants, stabilizers, etc.

[0029] In one embodiment, the epoxidized fatty acid ester that has not been subjected to transesterification is ESO, and the epoxidized fatty acid ester that has been subjected to transesterification is e-FAME.

[0030] In one embodiment a plasticizer blend for medical application is made from ESO and eFAME. In one embodiment the invention is the compatibility of the green plasticizer blend with PVC. The solubility of a plasticizer in PVC is well known to increase with increasing levels of oxirane oxygen in its composition. eFAME made from the epoxidation of FAME route has in general a lower oxirane oxygen level than eFAME made from transesterification of soybean oil. This increases plasticization efficiency and consequently can be used at a lower loading level to obtain similar reduction in the glass transition temperature (Tg) of PVC. Moreover, eFAME made from the transesterification route has a lower acid number than eFAME made from the epoxidation of FAME route. The green plasticizer blend is used with the PVC in known amounts and in known ways.

[0031] The green plasticizers and green plasticizer blends of this invention are useful in a broad range of applications including, but not limited to, various medical devices, e.g., syringes, tubing, etc., that come in contact with water containing substances, e.g., various body fluids such as blood and urine, saline solutions, etc., and packaging for various food stuffs and medical substances, e.g., various beverages (e.g., milk, water, juices, carbonated drinks, etc.), meats, frozen vegetables, blood and saline solution bags, and the like.

SPECIFIC EMBODIMENTS

Test Conditions

ESI/LC/MS and ESI/LC/MS/MS (Medium Resolution Conditions)

[0032] Six tenths of a microliter aliquots of the samples are injected on a Agilent 1200SL binary gradient liquid chromatograph coupled to a Agilent 6520 QTof, quadrupole-time of flight MS system via a dual spray electrospray (ESI) interface operating in the positive ion (PI) mode. The following analysis conditions are used:

Column: 50 x 2.1mm ID 1.8μηι Zorbax Eclipse Plus C18

Column temperature: 60°C Mobile phase: 80/20 A/B to 100B at 25 minutes (hold lOminutes)

A = 0.1 v% formic acid in water

B = 0.1 v% formic acid in acetonitrile

Flow: 0.35 mL/min

UV detection: Diode Array 210 to 400nm

ESI conditions: Gas Temp- 350°C Gas Flow - lOml/min

Capillary- 3.5 kV Nebulizer - 40PSI

Fragmentor -145V

AutoMSMS conditions: Mode - +TOFMS and +TOFMSMS; Centroid Resolution 12000(+)

2Ghz Extended Dynamic Range

Scan- 100 to 1700 amu (+MS) Rate- 3 scan/sec

Scan- 50 to 1700 amu (+MS/MS) Rate- 3 scan/sec

Collision Energy: 3.5V + 4V/100amu

Collision Gas: Nitrogen Isolation Width ~9 amu

Reference Ions: 121.050873: 922.009798 (+) 119.03632, 966.0008 (-)

HPLC/ELSD conditions

HPLC setup:

Mobile phase: H₂0/ Acetonitrile (A/B)

Column: ODS C-18; 2.1 x 100mm, 3μιη particle

Gradient: Time (min) %B (Acetonitrile)

0.0 88

1.8 88

2.6 100

7.0 100

9.0 88

1 1.0 88

Flow: 0.30 ml/min

Oven Temp.: 70°C

Injection: 2 μΐ.

Run Time: 1 1 min.

Post Time: 2 min. ELSD setup:

[0034] Instrument: Alltech 3300 ELSD

Tube Temp.: 70°C

Gas Flow: 1.80 SLPM

Gain: 1.0

N2 regulator: 60 psig

Example 1

[0035] Two experimental eFAME samples as received from a supplier and made by transesterification of ESO were analyzed for oxirane oxygen (in wt%) and acid numbers (in mg KOH/gm). The first sample measured as 6.84 and 0.4, respectively, and the second sample measured 6.9 and 0.2 respectively.

Comparative Example 1

[0036] Three different eFAME batches were received from a commercial supplier and all were made by the epoxidation of soy-FAME. The oxirane oxygen and acid number values for these three batches were measured as 6.4 and 1.1, 6.34 and 1.56, and 6.6 and 0.57, respectively. These oxirane oxygen values are significantly lower than the eFAME samples shown in Example 1 , where the acid numbers are found to be significantly higher.

Examples 2 & 3

[0037] Pure eFAME samples made from transesterification of ESO (sample made by a commercial supplier) are analyzed by ESI/LC/MS. Table 3 shows the summary of area percent of the most hydrophilic molecules (containing hydroxyls) for two different laboratory eFAME samples made in this manner (Samples 2 & 3). Also a summary of mass spectral data including assignments for all detected components is presented in Table 4, which shows the structure of these hydrophilic molecules. The accurate mass measurements for all detected components are within one milliDalton of the proposed structures. The results show that for the samples 2 and 3, the total area percent assigned for these hydrophilic molecules (A, B C and D) are about 1.32% and 1.14% respectively, and three hydrophilic structures (labeled A, B, and D in Table 4 are below detection level (ND in Table 3).

Comparative examples 2, 3 and 4 [0038] Three eFAME samples made by epoxidation of soy-FAME (Comparative Samples 2, 3 and 4) are also analyzed by ESI/LC/MS techniques and the results in Table 3 show that for all these samples the structure containing 4 hydroxyls are present (labeled as A). The area percent for this molecule ranges from 0.87% for Comparative Sample 2 to 1.43% for Comparative Sample 3, with Comparative Sample 4 showing a value (1.33%) close to Comparative Sample 3. When all 4 structures (labeled A, B, C and D) are taken into account, the area percent for Comparative Samples 2-4 come to about 3.83, 5.71, and 4.36% respectively, or in other words, about 3 to 4 times more than the eFAME samples made by transesterification of ESO as described in Examples 2 and 3.

TABLE 3

Summary of Area Percent of the Most Hydrophilic Molecules from the Accurate Mass

ESI/LC/MS Analyses of eFAME Samples

TABLE 4

Summary of Mass Spectral Data from the Accurate Mass ESI/LC/MS

Analyses of eFAME Samples from Various Vendors

Examples 5 & 6

[0039] Two eFAME samples, each from a different supplier and both made by transesterification of ESO, are analyzed for water-extractables by water-leaching study. In the water-leaching test, 0.04g of each sample is added to 8g of de-ionized (DI) water. The sample is then placed in a 40°C oven. High pressure liquid chromatograph - evaporative light scattering detection (HPLC-ELSD) analysis is performed on 1ml of the sample taken from the bottom of the vial after 24 hours. The area of the retention peak at 1.9 minutes is assigned to the soluble-in-water component from eFAME. The amount of these water- leachable compounds in eFAME is estimated by comparing the peak area at 1.8 minutes to the total peak areas for neat eFAME (dissolved in acetonitrile) from 1.5 to 4 min. The results show that the weight percent of the water-extracted portion is 0.12 wt% for one eFAME sample and 0.18 wt% for the other eFAME sample.

Comparative examples 5 and 6

[0040] Two eFAME samples, each from a different commercial supplier and both made by the epoxidation of FAME route, are subjected to the same water-leaching test as described for Examples 5 and 6 above. After 24 hours of water-extraction at 40°C, the results show that weight percent of the water-extracted portion is 0.55 wt% for one eFAME sample and 1.28 wt% for the other eFAME sample.

Example 7

[0041] A canola oil based eFAME sample is prepared in the laboratory by first epoxidizing canola oil to make ECO (epoxidized canola oil) and then transesterifying the ECO to produce eFAME. For epoxidation reaction, 50 gms of canola oil is fed to a 250 ml glass reactor. A C=C:H₂0₂: formic acid mole ratio of 1 :2:0.5 was used. The solution strength of incoming H₂0₂ was at 50 wt% and its feed-rate was controlled at 50 gm/hr. The reaction temperature is maintained at 60°C. A total of 6 hrs of reaction time is allowed before stopping the agitator and letting the aqueous and oil phases separate. The ECO thus produced is transesterified with methanol in a methanol to oil mole ratio of 6: 1. A 25% solution (in methanol) of sodium methoxide is used as the catalyst and added at 1 wt% loading based on the oil. The reaction temperature is maintained at 60°C and 3 hours of reaction time is allowed, following which the agitator is stopped and the oil and water layers are given sufficient time to separate. The canola-eFAME thus produced is analyzed for water-extractables by water-leaching study. In the water-leaching test, 0.04g of each sample is added to 8g of de-ionized (DI) water. The sample is then placed in a 40°C oven. High pressure liquid chromatograph - evaporative light scattering detection (HPLC-ELSD) analysis is performed on 1ml of the sample taken from the bottom of the vial after 24 hours. The area of the retention peak at 1.9 minutes is assigned to the soluble-in-water component from eFAME. The amount of these water-leachable compounds in eFAME is estimated by comparing the peak area at 1.8 minutes to the total peak areas for neat eFAME (dissolved in acetonitrile) from 1.5 to 4 min. The results show that the weight percent of the water- extracted portion is 0.34 wt%.

Comparative example 7

[0042] A canola oil based eFAME sample is prepared in the laboratory by first transesterifying the oil to produce canola-FAME and then epoxidizing the FAME to produce canola eFAME. The canola oil is transesterified with methanol in a methanol to oil mole ratio of 6: 1. A 25% solution (in methanol) of sodium methoxide is used as the catalyst and added at 1 wt% loading based on oil. The reaction temperature is maintained at 60°C and 3 hours of reaction time is allowed, following which the agitator is stopped and the oil and water layers are given sufficient time to separate. The canola-FAME thus produced is epoxidized with H₂0₂ and formic acid. For epoxidation reaction, 50 gms canola oil is fed to a 250 ml glass reactor. A C=C:H₂0₂: formic acid mole ratio of 1 :2:0.5 is used for the reactants. The solution strength of incoming H₂0₂ is at 30 wt% and its feed-rate is controlled at 25 gm/hr. The reaction temperature is maintained at 40°C. A total of 1 1 hrs of reaction time is allowed before stopping the agitator and letting the aqueous and oil phase separate. The canola-eFAME thus produced is subjected to the same water-leaching test as described for Examples 5 and 6 above. After 24 hours of water-extraction at 40°C, the results show that weight percent of the water-extracted portion is 1.

[0043] Although the invention has been described with certain detail through the preceding description of the preferred embodiments, this detail is for the primary purpose of illustration. Many variations and modifications can be made by one skilled in the art without departing from the spirit and scope of the invention as described in the following claims.

Claims

What is claimed is:

1. A process for making a green plasticizer, the process comprising the steps, in any order, of epoxidizing and transesterifying a natural oil having (1) an iodine number (IV) of 60 or more, and (2) a linolenic acid content of 5 weight percent (wt%) or less based on the weight of the oil.

2. The process of Claim 1 in which the natural oil is first epoxidized and then transesterified.

3. The process of Claim 1 in which the natural oil is first transesterified and then epoxidized.

4. The process of Claim 1 in which the natural oil is derived from at least one of corn kernels, sunflower seeds, cotton seeds, safflower seeds and olives.

5. A process for making a green plasticizer, the process comprising the steps of epoxidizing natural oil with (1) an iodine number (IV) of 60 or more, and (2) a linolenic acid content of 5 weight percent (wt%) or more based on the weight of the oil, and then transesterifying the epoxidized oil to make an epoxidized fatty acid alkyl ester.

6. The process of Claim 5 in which the oil is at least one of soy oil, linseed oil and canola oil.

7. The process of Claim 6 in which the epoxidized fatty acid alkyl ester is epoxidized fatty acid methyl ester.

8. The process of Claim 5 comprising the further step of blending the transesterified epoxidized fatty acid alkyl ester with epoxidized natural oil that has not been transesterified.

9. The process of Claim 8 in which the epoxidized natural oil that has not been transesterified is epoxidized soy oil (ESO)

10. The process of Claim 8 in which the epoxidized natural oil is blended with the transesterified epoxidized fatty acid alkyl ester at an epoxidized natural oil to transesterified epoxidized fatty acid alkyl ester weight ratio of 90: 10 to 10:90.

11. A green plasticizer made by the process of Claim 5.

12. A plastic comprising the green plasticizer of Claim 1 1.

13. An object comprising the plastic of Claim 12.

14. The object of Claim 13 in which the plastic is PVC.

15. The object of Claim 14 in the form of a medical device or packaging for food or medical products.