Oxygenated Solvent Odor Removal Composition

Abstract

An odor elimination composition for oxygenated solvents comprising an alcohol amine.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present disclosure generally relate to odorant-removing agents and methods for controlling odor in oxygenated solvents, where the odorant-removing agent includes at least an amino alcohol. Introduction

[0002] Consumers are becoming increasingly aware of and concerned about indoor and outdoor air quality. While more and more coating formulations have been switched to water-based formulations, there is a clear market need driving coating manufacturers to provide coatings with lower VOC (volatile organic compound) emissions and lower odor. More restrictive regulations regarding VOC emissions are also increasing the demand for lower odor coatings.

[0003] Dipropylene glycol monobutyl ether (DPnB) and dipropylene glycol monomethyl ether (DPM) are two examples of oxygenated solvents commonly used in waterborne wood coatings. There is a strong demand for these glycol ether solvents to have lower odors. However, DPnB and DPM currently often contain some impurities in the final composition. These impurities can contribute to high VOC emissions and induce strong odors during solvent evaporation. Additionally, the amount of these impurities can further increase under heating conditions due to oxidation, thereby contributing to higher VOC emissions and stronger odors.

[0004] Generally, impurities in oxygenated solvent products include aldehydes, ketones, acids, esters, and their derivatives. These impurities can be introduced from alcohols (used as feedstocks in solvent production), generated during the alkoxylation process, or formed by oxidation during storage. This oxidation can be accelerated at higher temperatures, which leads to the decomposition of the alkoxylate chains with formaldehyde (a VOC) being formed as one of many decomposition products.

[0005] For all these reasons and more, there is a need for odor-controlled packaging and methods for controlling odor in oxygenated solvents. Summary of the Invention

[0006] Embodiments of the present invention generally relate to aminoalcohol odorant-removing agents that, together with antioxidants, effectively reduce odorant content in oxygenated solvents. Embodiments of the present invention also relate to methods for controlling odor in oxygenated solvents by using the odor-removing compositions. Embodiments of the present invention also relate to oxygenated solvents containing the odor-removing compositions. DETAILED DESCRIPTION OF THE INVENTION

[0007] The present disclosure relates to an odorant eliminator and a method for controlling odors and volatile chemical compounds (VOCs) in oxygenated solvents. In one embodiment, the odorant eliminator can be an amino alcohol blended with an antioxidant to effectively reduce odorant content in oxygenated solvents. This odorant eliminator can act to reduce odorants at lower dosages, allowing for easier processing conditions with improved performance.

[0008] The odor eliminating composition comprises an amino alcohol. In one embodiment, the general structure of the amino alcohol used in the odor eliminating composition is shown below:

[0009] [ka] wherein R1, R2, and R3 can be H, an alkylamine, or a hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8. R4 can be an alkylamine or a hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8. Examples of aminoalcohols that can be used include, but are not limited to, diethanolamine (DEA, CAS#: 111-42.2) or aminoethyl ethanolamine (AEEA, CAS#: 111-41-1) in some embodiments.

[0010] The odor-removing composition may also include at least one antioxidant, which may include, but is not limited to, synthetic vitamin E (d, la-tocopherol, CAS#: 10191-41-0) and phenolic antioxidants such as propyl gallate (CAS#: 121-79-9).

[0011] The reduction of odor in oxygenated solvents can be achieved by several different methods. For example, in one embodiment, odorant eliminators and antioxidants can be added directly to the oxygenated solvent after the solvent is produced. This is notable and advantageous because post-process addition of odorant eliminators means there is little impact on current solvent manufacturing processes. This provides a cost-effective, low-impact means for achieving lower odor oxygenated solvents.

[0012] In one embodiment, a method for controlling odor in an oxygenated solvent comprises: (a) providing an oxygenated solvent having the following formula: R1-O-(CHR2CHR3)O)nR4, wherein R1 ranges from a C1 to C9 linear or branched alkyl group or is a phenyl group; R2 and R3 are H or a C1 to C2 alkyl; when R3 is C1 to C2, R2 is H; when R2 is C1 to C2, R3 is H; R4 is H; and n is an integer from 1 to 6; and (b) adding at least one alcohol amine to the oxygenated solvent, wherein the at least one alcohol amine has the following structure:

[0013] [ka] wherein R1, R2, and R3 are H, an alkylamine, or a hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8, and R4 is an alkylamine or a hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8. In some embodiments, the method further comprises adding at least one antioxidant to the oxygenated solvent. Antioxidants may include, but are not limited to, synthetic vitamin E (d,1a-tocopherol, CAS#: 10191-41-0) and phenolic antioxidants such as propyl gallate (CAS#: 121-79-9).

[0014] In one embodiment, the odor elimination compositions each comprise, based on the total weight of the composition, 0.001 to 1 weight percent of an aminoalcohol described herein, 0 to 1 weight percent of at least one phenolic antioxidant, less than 1 weight percent water, and more than 90 weight percent of an oxygenated solvent. In another preferred embodiment, the odor elimination compositions each comprise, based on the total weight of the composition, 0.001 to 0.25 weight percent of an aminoalcohol described herein, 0 to 0.25 weight percent of at least one phenolic antioxidant, less than 0.5 weight percent water, and more than 95 weight percent of an oxygenated solvent. In yet another preferred embodiment, the odor elimination compositions each comprise, based on the total weight of the composition, 0.001 to 0.1 weight percent of an aminoalcohol described herein, 0.001 to 0.1 weight percent of at least one phenolic antioxidant, less than 0.3 weight percent water, and more than 98 weight percent of an oxygenated solvent.

[0015] Oxygenated solvents may include, but are not limited to, solvents having the following formula: R1-O-(CHR2CHR3)O)nR4, where R1 ranges from C1 to C9 linear or branched alkyl groups or is a phenyl group, R2 and R3 are H or C1 to C2 alkyl, and when R3 is C1 to C2, R2 is H, and when R2 is C1 to C2, R3 is H and R4 is H, and n is an integer from 1 to 6.

[0016] Still other examples of oxygenated solvents may include, but are not limited to, dipropylene glycol monobutyl ether and dipropylene glycol monomethyl ether (DOWANOL™ DPM Glycol Ether and DOWANOL™ DPnB Glycol Ether available from Dow Chemical) and butanol-initiated ethoxylated solvents (Butyl CARBOTOL™ available from Dow Chemical).

[0017] The present invention can be utilized to remove odors from batches of freshly produced oxygenated solvents and can also be used to treat oxygenated solvents that have been stored for extended periods. Stored oxygenated solvents tend to produce more odorous molecules, such as the cyclic ethers 2,4-dimethyl-1,3-dioxolane (DMD), 2-ethyl-4-methyl-1,3-dioxolane (EMD), or trioxocane, which are themselves strong odorants. DMD and EMD can be formed by the derivatization of propylene glycol and acetaldehyde or propionaldehyde during storage. The present invention can be added to oxygenated solvents to reduce these odorants over long periods of time.

[0018] In another embodiment of the present invention, the amino alcohols shown below may be combined with an antioxidant without the need for an oxygenated solvent to be present:

[0019] [ka] where R1, R2, and R3 can be H, an alkylamine, or a hydroxylalkyl group having a straight or branched carbon chain ranging from C1 to C8, and R4 can be an alkylamine or a hydroxylalkyl group having a straight or branched carbon chain ranging from C1 to C8.

[0020] Some embodiments of the present invention also relate to an oxygenated solvent comprising an odor removal composition. In some embodiments, such an oxygenated solvent comprises: an oxygenated solvent having the following formula: R1-O-(CHR2CHR3)O)nR4, wherein R1 ranges from a C1 to C9 straight or branched chain alkyl group or is a phenyl group, R2 and R3 are H or a C1 to C2 alkyl, and when R3 is C1 to C2, R2 is H, and when R2 is C1 to C2, R3 is H, R4 is H, and n is an integer from 1 to 6; (a) the structure:

[0021] [ka] and at least one alcoholamine having the formula: wherein R1, R2, and R3 are H, an alkylamine, or a hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8, and R4 is an alkylamine or a hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8. In some embodiments, the oxygenated solvent further comprises at least one antioxidant. Antioxidants may include, but are not limited to, synthetic vitamin E (d,1a-tocopherol, CAS#: 10191-41-0) and phenolic antioxidants such as propyl gallate (CAS#: 121-79-9). In some embodiments, the oxygenated solvent comprises, each based on the total weight of the composition, 0.001 to 1 weight percent amino alcohol, 0 to 1 weight percent at least one phenolic antioxidant, less than 1 weight percent water, and more than 90 weight percent oxygenated solvent. In another embodiment, the oxygenated solvent comprises 0.001 to 0.25 weight percent of an aminoalcohol described herein, 0 to 0.25 weight percent of at least one phenolic antioxidant, less than 0.5 weight percent water, and more than 95 weight percent oxygenated solvent, each based on the total weight of the composition. In yet another embodiment, the oxygenated solvent comprises 0.001 to 0.1 weight percent of an aminoalcohol, 0.001 to 0.1 weight percent of at least one phenolic antioxidant, less than 0.3 weight percent water, and more than 98 weight percent oxygenated solvent, each based on the total weight of the composition.

[0022] Some embodiments of the present invention will now be discussed in detail in the following examples. [Example]

[0023] The following examples test the effectiveness of odor eliminating compositions and the like of the present disclosure.

[0024] I. Material

[0025] [Table 1]

[0026] II. Odor Removal Test Test Method A specific amount of amino alcohol and / or antioxidant is added to a volume of a given solvent (approximately 20 mL) at room temperature (see Table 2 for all component compositions tested). Examples are designated in the test results below with the suffix "IE" to denote an example of the present invention (e.g., IE-M7). Other comparative examples not containing amino alcohol and / or antioxidant (or either) are also prepared for each round of testing and are designated in the results below with the suffix "CE" (e.g., CE-M1).

[0027] The mixture of amino alcohol and / or antioxidant with the solvent (or comparative example) was then placed on a shaking table at 300 RPM for 2 hours to achieve a homogeneous appearance. Once this shaking was complete, the mixture was then maintained at room temperature for 48 hours and then subjected to various forms of odorant testing, including headspace GC-MS analysis, SPME PFBHA derivatization GC-MS, and SPME GC-MS. Details of each of these test methods are listed below. The results for this portion of the test can be found in Tables 3 and 4. The odorant removal dosage can also be optimized by combining the amino alcohol with the antioxidant. The results for this portion of the test can be found in Tables 5 and 6. The odorant removal ability against aged oxygenated solvents can also be tested, and the results for this portion of the test are shown in Tables 7 and 8. The odorant removal ability against EO-based oxygenated solvents can also be tested, and the results for this portion of the test are shown in Table 9.

[0028] Headspace GC-MS method: Headspace GC-MS equipment: 7890A gas chromatograph with 7697A headspace autosampler, 5975C mass spectrometer. GC column: SOLGEL-Wax (sn. 1297586B08, p / n 054787), 30 m x 250 μm x 0.25 μm. Carrier gas: Helium carrier gas at a constant flow rate of 1.0 mL / min. GC oven program: Hold at 50 °C for 5 min, ramp to 250 °C at 10 °C / min, hold for 3 min. MSD parameters (scan mode): MS source temperature: 230 °C, MS quad temperature: 150 °C, Acq. mode: Scan, mass range: 29–400 Daltons. Headspace oven conditions: Heat at 130 °C for 15 min. Sample preparation: 20–30 mg of sample was placed in a 20 mL headspace vial for analysis. Several samples per experiment were prepared in triplicate, and average results are reported. All VOCs were semi-quantified using toluene as a standard. A 4 μL aliquot of a toluene solution (500 μg / g) prepared in acetonitrile (ACN) was injected into a headspace vial, and the toluene peak area was used for semi-quantification.

[0029] SPME on-fiber derivatization method: Analysis for the presence of acetaldehyde was performed using SPME-on-fiber derivatization. The SPME-on-fiber derivatization parameters were as follows: Headspace GC-MS instrument: 7890A gas chromatograph equipped with a 7697A headspace autosampler, 5975C mass spectrometer; GC column: DB-5, 30 m x 250 μm x 0.25 μm; Carrier gas: Helium carrier gas at a constant flow rate of 1.0 mL / min; MSD parameters (scan mode): MS source temperature: 230 °C; MS quad temperature: 150 °C; Acq. mode: Scan, mass 29–400 Daltons; Oven program: 50 °C for 3 min, then 15 °C / min to 180 °C for 0 min; Sample preparation: 0.5 g of sample was added to a 20 mL headspace vial. Aldehyde standards: 2 μL of a mixture of aldehydes (1 ppm each) was injected into a 20 mL headspace vial for quantification of the various aldehydes.

[0030] SPME on-fiber derivatization parameters were as follows: SPME fiber type: 65 μm PDMS-DVB (Supleco Co. Ltd., 57321-U) On-fiber derivatization: 5 min, 50°C Derivatization agent: O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA·HCl, 99+%). 1 mL (17 mg / mL) in a 20 mL headspace vial. Incubation time: 5 minutes at 60°C. ·Extraction: 5 minutes, 60℃.

[0031] SPME (solid phase micro-extraction) GC-MS method: SPME GC-MS analysis was performed on an Agilent 6890 gas chromatograph coupled with a mass spectrometry detector (Agilent 5975C MSD). The GC conditions are listed in the table below. Semi-quantification was performed with reference standards (5 ppm each, prepared in Polyol 8010).

[0032] Oven program: Initial temperature: 50°C (on), Max temperature: 325°C, Initial time: 4.00 min, Equilibration time: 0.50 min. Ramp: Rate (16) Final (250) Temperature (2) Run time: 18.50 min Ambient temperature: 25°C. SPME conditions: PDMS / DVB SPME fiber from Supleco Co.ltd, Incubation temperature: 75°C, Incubation time: 5.00 min, Extraction time: 30 min.

[0033] Agilent 19091S-433, HP-5MS, 5% Phenyl Methyl Silox, 30 m x 250 μm, film thickness 0.25 μm, mode: constant pressure, pressure: 7.6522 psi, nominal initial flow rate: 1 mL / min, average velocity: 36.445 cm / sec.

[0034] MS SCAN and SIM parameters: DMD / EMD quantification: Resolution: Low, Group start time: 2.30, Plot 1 ions: 72.00, Ions / dwell in group (mass, dwell) (mass, dwell) (mass, dwell) (59.00, 30) (72.00, 30) (87.00, 30). Trioxocane quantification: Resolution: Low, Group start time: 8.00, Plot 1 ions: 101.00, Ions / dwell in group (mass, dwell) (mass, dwell) (mass, dwell) (59.00, 30) (101.00, 30) (130.00, 30).

[0035] [Table 2]

[0036] result

[0037] [Table 3]

[0038] Note: The unit is PPM (based on headspace GC-MS method), and the LOQ (lower limit of quantification) is approximately 0.1 ppm (very low level).

[0039] [Table 4]

[0040] NOTE: The units are in PPM (based on headspace GC-MS method), and the LOQ is approximately 0.1 ppm (very low level).

[0041] [Table 5]

[0042] NOTE: The units are in PPM (based on headspace GC-MS method), and the LOQ is approximately 0.1 ppm (very low level).

[0043] [Table 6]

[0044] NOTE: The units are in PPM (based on headspace GC-MS method), and the LOQ is approximately 0.1 ppm (very low level).

[0045] [Table 7]

[0046] Note: The units are in ppm (based on headspace GC-MS method), and the LOQ is approximately 0.1 ppm (very low level). The units are μg / m 3 (by SPME on-fiber derivatization method) and the LOQ was approximately 1.0 μg / m 3 The units are in PPM (by SPME (solid phase microextraction) GC-MS method) and the LOQ is 0.005 ppm. DMD / EMD / trioxocane are cyclic ethers that are typically formed as derivatization of propylene glycol and acetaldehyde or propionaldehyde during storage.

[0047] [Table 8]

[0048] Note: The units are in ppm (based on headspace GC-MS method), and the LOQ is approximately 0.1 ppm (very low level). The units are μg / m 3 (by SPME on-fiber derivatization method) and the LOQ was approximately 1.0 μg / m 3 The units are in PPM (by SPME (solid phase microextraction) GC-MS method) and the LOQ is 0.005 ppm. DMD / EMD / trioxocane are cyclic ethers that are typically formed as derivatization of propylene glycol and acetaldehyde or propionaldehyde during storage.

[0049] [Table 9] Note: The units are in PPM (based on headspace GC-MS method).

[0050] III.Discoloration test Test Method In one series of experiments, approximately 20 mL of neat DOWANOL™ DPM without additives was stored at room temperature as Comparative Example 1 (CE-M17). A DPM sample without additives was stored at 54°C as Comparative Example 2 (CE-M18). DPM samples with DEA, AEEA, or tris-amine were marked as Examples (IE-M19, IE-M20, or IE-M21). Samples containing SVE or PG were marked as CE-M22 and CE-M3, respectively. Next, samples with DOWANOL™ DPnB and the above-mentioned additives were also prepared and labeled similarly, except with a "B" instead of an "M" in their names (see Table 10). Table 10 lists all the component compositions tested.

[0051] To monitor the color evolution of the sample in the presence of various additives, color data is then measured. Color measurements are performed using a color tester Ultra Scan VIS USVIS2052. For each sample measurement, the sample cell is washed with deionized water and ethanol and dried by blowing compressed air. Approximately 15 mL of solvent is then poured into the test cell, which is then placed in the tester and compared with the reference sample. The results of the tests performed in this manner are listed in Tables 11A and 11B below.

[0052] [Table 10]

[0053] result

[0054] [Table 11] Note: The color unit is Pt-Co.

[0055] [Table 12] Note: The color unit is Pt-Co.

[0056] IV. Essay Based on the odorant removal results in DOWANOL™ DPM (Table 3) and DOWANOL™ DPnB (Table 4), DEA (IE-M3 and IE-B3) and AEEA (IE-M4 and IE-B4) performed surprisingly well in removing odorant impurities compared to the blank control comparative examples (CE-M1 and CE-B1).

[0057] Based on the headspace GC-MS analysis results in Tables 5 and 6, amino alcohols alone and in combination with antioxidants demonstrated unexpected improvements in odorant removal efficiency (IE-M8, IE-M9, IE-M10, IE-M11, IE-B8, IE-B9, IE-B10, IE-B11). One notable example is DEA and SVE in DPM, which showed a strong synergistic effect between the amino alcohol and antioxidant (IE-M11).

[0058] Based on the analysis results of the aged samples in Tables 7 and 8, after 3 months of storage at 54°C, the odorant impurity content increased significantly for both DPM and DPnB. Notably, AEEA (IE-M14 and IE-B14) maintained very low amounts of aldehyde content in DPM and DPnB after 13 weeks. Synergistic improvement of combining AEEA with antioxidants was also observed in these tests (IE-M16 and IE-B16). Additionally, strong cyclic ether (DMD / EMD / trioxocane) removal performance was observed for these examples.

[0059] Based on the data in Table 9, amino alcohols or blends of amino alcohols and antioxidants work well with EO-based solvents (IE-BC2 and IE-BC4).

[0060] Based on the color stability results of the additives in DOWANOL™ DPM (Table 11A) and DOWANOL™ DPnB (Table 11B) after 13 weeks of aging at 54°C, the DPM and DPnB samples with additives did not show significant color changes (IE-M19 to CE-M22 and IE-B19 to CEB22), except for the samples containing propyl gallate (CE-M23 and CE-B23). The present invention encompasses the following aspects. [1] An odor removal composition for oxygenated solvents, comprising the following structure: [ka] wherein R 1 、R 2 , and R 3 is H, an alkylamine, or a hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8, and R4 is an alkylamine or hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8. [2] The odor removal composition for oxygenated solvents according to [1] above, wherein the composition further comprises at least one antioxidant. [3] The odor removal composition for oxygenated solvents according to [2] above, wherein the at least one antioxidant is a phenolic antioxidant. [4] The odor removal composition for oxygenated solvents according to [1], wherein the at least one alcoholamine is aminoethylethanolamine, diethanolamine, or tris-(hydroxyl-methyl)amino-methane. [5] A method of controlling odor in an oxygenated solvent by use of an odor-removing composition, said odor-removing composition having the following structure: [ka] wherein R 1 、R 2 , and R 3 is H, an alkylamine, or a hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8; R 4 is an alkylamine or hydroxylalkyl group having a straight or branched carbon chain ranging from C1 to C8. [6] The method according to [5], wherein the composition further comprises at least one antioxidant. [7] The method according to [6] above, wherein the at least one antioxidant is a phenolic antioxidant. [8] The method according to [5], wherein the alcoholamine is aminoethylethanolamine, diethanolamine, or tris-(hydroxyl-methyl)amino-methane. [9] The method according to [5], wherein the method is used to control the odor of one or more oxygenated solvents.

[10] The oxygenated solvent is R 1 -O-(CHR 2 CHR 3 )O)nR 4 wherein R 1 is a C1 to C9 linear or branched alkyl group or a phenyl group, and R 2 and R 3 is H or C1-C2 alkyl, and R 3 If C1 to C2, then R 2 is H and R 2 If C1 to C2, then R 3 is H and R 4 The method according to [8] above, wherein is H and n is an integer of 1 to 6.

Claims

1. 1. An odor elimination composition for oxygenated solvents, comprising, based on the total weight of the composition: The following structure: 【Chemistry 1】 at least one alcohol amine having the formula １ , R ２ , and R ３ is H, an alkylamine, or a hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8; R ４ comprises 0.001 to 1 weight percent of an alcoholamine, which is an alkylamine or hydroxylalkyl group having a linear or branched carbon chain ranging from C1 to C8, and greater than 90 weight percent of an oxygenated solvent; the oxygenated solvent is An odor removal composition for oxygenated solvents, the odor removal composition being selected from the group consisting of: a solvent having the structure R 1 -O-((CHR 2 CHR 3 )O)nR 4 , wherein R 1 is a straight or branched alkyl group ranging from C1 to C9 or a phenyl group, R 2 and R 3 are H or a C1 to C2 alkyl, and when R 3 is C1 to C2, R 2 is H, and when R 2 is C1 to C2, R 3 is H, R 4 is H, and n is an integer from 1 to 6; dipropylene glycol monobutyl ether; dipropylene glycol monomethyl ether; and diethylene glycol monobutyl ether.

2. 10. The odor removal composition for oxygenated solvents of claim 1, wherein said composition further comprises at least one antioxidant.

3. 3. The odor removal composition for oxygenated solvents of claim 2, wherein said at least one antioxidant is a phenolic antioxidant.

4. 2. The odor removal composition for oxygenated solvents of claim 1, wherein the at least one alcohol amine is aminoethylethanolamine, diethanolamine, or tris-(hydroxyl-methyl)amino-methane.

5. 5. A method for controlling odor in oxygenated solvents by use of the odor removing composition of any one of claims 1 to 4.

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