Keto acid esters as PVC plasticizers

Abstract

Resin plasticizers are produced by esterification of keto acids derived from acylation of aromatic compounds with cyclic anhydrides, and are particularly useful in making phthalate-free articles using PVC.

Claims

1. A process for producing keto acid esters, the process comprising: (a) a first step of Friedel crafts reaction of benzoyl chloride with benzene in the presence of an acidic catalyst comprising AlCl.sub.3 to form benzophenone, a second step reaction of benzophenone with CO/HCl in a Gattermann-Koch reaction to form benzophenone aldehyde, a third step of the oxidation of the aldehyde to the acid, a fourth step of the esterification with an ROH alcohol, as illustrated in the following scheme: ##STR00005## (b) a first step reaction of benzoate ester with CO/HCl in a Gatterman-Koch reaction, a second step formation of acid chloride in the presence of SOCl.sub.2, a third reaction Friedel Crafts acylation in the presence of benzene and AlCl.sub.3, as illustrated in the following schematic: ##STR00006## wherein said ROH alcohol comprises a C6 to C13 alcohol derived from the oligomerization of at least one C3-C6 olefin to form an oligomer, followed by hydroformylation and hydrogenation reactions of said oligomer to form said C6 to C13 alcohol.

2. The process of claim 1, wherein said hydroformylation reaction is catalyzed by a metal selected from Rh, Co, and mixtures thereof.

3. The process of claim 1, wherein said hydroformylation reaction is catalyzed by Co.

4. The process of claim 1, wherein said hydroformylation reaction is catalyzed by Rh.

5. The process of claim 1, wherein said oligomerization is catalyzed by solid phosphoric acid, a zeolite, or a combination thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) The invention is directed to keto acid esters and their use as plasticizers, particularly with PVC resins.

(2) In embodiments, the keto acid esters are derived by acylating an aromatic molecule, such as benzene, toluene, one or more xylenes, anisole or other aromatic ethers, or mixtures of aromatic molecules, in a Friedel-Crafts type or condensation reaction, with a cyclic anhydride, such as succinic anhydride, phthalic anhydride, and the like. The resulting keto acid is esterified using an alcohol.

(3) In embodiments the alcohol are derived from C6 to C13 aldehydes obtained from a hydroformylation process.

(4) In preferred embodiments, the process further comprises providing a feed for the hydroformylation process from dimerization of diverse feedstock, preferably dimerization of a C3 or C4 feedstock, or a mixture thereof.

(5) The invention is also directed to keto acid esters, particularly keto acid esters wherein the alcohol moiety is derived from branched C6 to C13 alcohols, and also to compositions including a resin, such as PVC, and a keto acid ester according to the invention.

(6) The keto acid esters of the invention are derived by acylating an aromatic molecule such as benzene, toluene, anisole or other aromatic ethers, one or more xylenes, or mixtures of aromatic molecules. Typical aromatic molecules useful in this reaction include benzene, toluene, xylenes, propylbenzene, cumene, tort-butylbenzene, sec-butylbenzene, isobutylbenzene, isopentylbenzene, (1,2-dimethyl-propyl)-benzene, pentylbenzene, 1-phenylhexane, heptylbenzene, 1-phenyloctane, 1-phenylnonane, undecylbenzene, 1-phenylundecane, 1-phenyldodecane, 1-phenyltridecane, tetradecylbenzene, 1-phenyltetradecane, 1-phenylpentadecane, hexadecylbenzene, anisole, veratrole, naphthalene and substituted naphthalenes.

(7) The cyclic anhydride may be selected from at least one of phthalic anhydride, succinic anhydride, maleic anhydride, cyclohexanedicarboxylic anhydride, methylsuccinic anhydride, 2,2-dimethylsuccinic anhydride, hexabydro-4-methylphthalic anhydride, itaconic anhydride, norbornene-dicarboxylic anhydride, glutaric anhydride, dimethylglutaric anhydride, epoxy-tetrahydrophthalic anhydride, tetrahydrophthalic anhydride, diglycolic anhydride, 2-phenylglutaric anhydride, homophthalic anhydride, and methylphthalic anhydride.

(8) Acylation reactions with cyclic anhydrides are well-known per se (see Friedel-Crafts and Related Reaction, George Olah, Ed., Vol. 3 Part 1, Chapter XXXIV Acylation with Di- and Polycarboxylic Acid Derivatives by Andrew G. Peto, interscience, 1964, for example). An aromatic keto acid is produced when an aromatic compound is reaction with a cyclic anhydride in the presence of an acidic catalyst. The catalyst may be a Lewis acid catalyst, such as AlCl.sub.3, a protonic acid or solid acid catalysts, such as zeolites or sulfated zirconia, among others.

(9) In embodiments the alcohol are derived from C6 to C13 aldehydes obtained from a hydroformylation process, and in preferred embodiments, the process further comprises providing a feed for the hydroformylation process from dimerization of diverse feedstock, preferably oligomerization, such as dimerization or trimerization, of a feedstock selected from C3 to C6 olefins.

(10) In embodiments, the alcohol with which the keto acid is esterified will have an average branching of from about 0.8 to about 3.0. In an embodiment, the average branching may range from about 1.0 to about 2.4. In another embodiment, the average branching will range from about 1.2 to about 2.2, preferably around about 1.2 to about 2.0, more preferably about 1.2 to about 1.8 branches per molecule.

(11) Branching may be determined by known NMR methods, such as employed in U.S. Pat. No. 6,437,170. Branching may also be attenuated by one of ordinary skill in the art by appropriate process conditions and reagents. In embodiments the branching in these alcohols may be almost exclusively methyl branches but some ethyl branches may also be present in small amounts.

(12) In an embodiment, the process of the invention further comprises the production of branched aldehydes by hydroformylation of C5 to C13 olefins that in turn have been produced by oligomerization of propylene and/or butene over solid phosphoric acid or zeolite catalysts or nickel based dimerzation technologies or through the Dimersol process. These oligomerization processes are per se well-known. See, for instance, U.S. Pat. No. 7,253,330, and U.S. Pat. No. 7,145,049.

(13) The resulting C6 to C13 aldehydes are then hydrogenated to yield the corresponding primary alcohols.

(14) The plasticizers of this invention can then be prepared through the esterification of the keto acids with these C6 to C13 alcohols.

(15) The production of the keto acids and then corresponding esters, according to the invention may be conveniently exemplified by the following reactions, shown schematically. These reaction schemes are depicted with mono-substituted aromatics but a wide range of aromatics may be used. For example, benzene (RH), toluene (RCH3, xylenes (disubstituted with two RCH3 groups). Similarly, ROH may cover a range of alcohols, such as described previously.

(16) ##STR00001##

(17) In the case of the aroyl benzoic acid molecule derived from phthalic anhydride, shown in equation 2, the esterification can also yield another isomeric structure via rearrangement, as shown in equation 3. The final esterification product can be a mixture of the ester shown in equation 2 and the lactone shown in equation 3.

(18) Another synthetic route to the keto acids of the invention is by the method illustrated below, wherein the alkyl groups on R1 may be selected from linear or branched alkyls, preferably having from 1 to 6 carbon atoms.

(19) ##STR00002##

Example 1

(20) General procedure for synthesis of the plasticizer by esterification. Into a four necked 1000 ml round bottom flask equipped with an air stirrer, nitrogen inductor, thermometer, Dean-Stark trap and chilled water cooled condenser were added keto acid and Oxo alcohol in a mole ratio of 1:2. The reaction mixture was heated to 220 C. with air stirring under a nitrogen sweep. The water evolved during the esterification reaction was collected in the Dean-Stark trap and was drained frequently and monitored until approximately theoretical weight was collected, indicating near complete reaction. The excess alcohol were removed by distillation or steam stripping. In some instances, titanium isopropoxide was used as a catalyst for the esterification reaction.

(21) Table 1 summarizes the aroyl benzoates prepared from the reaction of an aromatic with phthalic anhydride. A general structure for the aroyl benzoates is shown below:

(22) TABLE-US-00001 TABLE 1 R R H C.sub.6H.sub.13 H C.sub.9H.sub.19 H C.sub.10H.sub.21 H C.sub.12H.sub.25 H C.sub.13H.sub.27 CH.sub.3 C.sub.5H.sub.11 CH.sub.3 C.sub.6H.sub.13 CH.sub.3 C.sub.9H.sub.19

(23) Table 2 summarizes the aroyl propionates prepared from the reaction of an aromatic with succinic anhydride. A general structure for the aroyl propionates is shown below:

(24) TABLE-US-00002 TABLE 2 R R H C.sub.9H.sub.19 H C.sub.13H.sub.27 CH.sub.3 C.sub.9H.sub.19 CH.sub.3 C.sub.13H.sub.27 2 CH.sub.3 * C.sub.9H.sub.19 2 CH.sub.3 * C.sub.10H.sub.21 t-C.sub.4H.sub.9 C.sub.9H.sub.19 * 1,3-dimethylbenzene

Example 1

Plasticization

(25) Formulations corresponding to Table 3, were mixed at room temperature with moderate stirring, then placed on a roll mill at 340 F. and milled for 6 minutes. The flexible vinyl sheet was removed and compression molded at 350 F.

(26) Sample A DINP=di-isononylphthalate

(27) Sample B TBA-9=iso-nonyl toluoyl benzoate

(28) Sample C TPA-9=iso-nonyl toluoyl propionate

(29) TABLE-US-00003 TABLE 3 Formulation -A -B -C PVC 100 100 100 Plasticizer DINP TBA-9 TPA-9 Phr 50 50 50 ESO 3 3 3 CuZn Stabilizer 3 3 3 stearic acid 0.25 0.25 0.25

(30) Comparison of the data for the formulations follows:

(31) TABLE-US-00004 TABLE 4 Mechanical Properties Comparison Sample ID A B C Original Mechanical Properties Shore A Hardness (15 sec.) 78.0 79.2 71.6 95% Confidence Interval 0.5 0.6 2.3 Shore D Hardness (15 sec.) 26.1 28.5 21.0 95% Confidence Interval 0.3 0.5 0.3 100% Modulus Strength, psi 1668 2123 1233 95% Confidence Interval 26 30 33 Ultimate TensileStrength, psi 2987 3351 3116 95% Confidence Interval 174 35 56 Ultimate Elongation, % 322 309 364 95% Confidence Interval 31 13 13 Aged Mechanical Properties: 7 Days at 100 C. (AC/hour) Aged 100% Modulus Strength, psi 2114 2611 95% Confidence Interval 13 24 Ultimate TensileStrength, psi 2822 2997 5869 95% Confidence Interval 86 88 336 Ultimate Elongation, % 265 214 28 95% Confidence Interval 20 17 11 Weight Loss, Wt % 5.9 6.2 20.7 95% Confidence Interval 0.28 0.12 0.28 Retained Properties: 7 Days at 100 C. (AC/hour) Retained 100% Modulus Strength, % 127 123 95% Confidence Interval 0.4 0.3 Retained Tensile Strength, % 94 89 188 95% Confidence Interval 0.4 0.3 0.7 Retained Elongation, % 82 69 8 95% Confidence Interval 1.7 1.4 0.9 Low Temperature Clash Berg (Tf), C. 21.9 3.8 18.9 95% Confidence Interval 0.8 1.2 1.2 Samples were milled at 340 F. and molded at 350 F. to thickness. Conditioning was 7 days prior to testing

(32) TABLE-US-00005 TABLE 4a Mechanical Properties Comparsion TSR # 09-020 Wet Blends Sample ID: D E Formulations: PVC (Oxy 240) 100 100 isodecylbenzoylbenzoate (BBA-10) 50 Jayflex DINP 50 ESO (Drapex 6.8) 3 3 CaZn stabilizer (Mark 1221) 2.5 2.5 Stearic Acid 0.25 0.25 Sample Prep & Observations: Samples were milled at 330 Low-moderate Low-moderate F. and molded at 340 F. smoking; smoking; low odor low odor Original Mechanical Properties Shore A Hardness (15 sec.) 76.8 78.5 95% Confidence Interval 1.2 1.1 100% Modulus Strength, psi 2013 1674 95% Confidence Interval 67 22 Ultimate TensileStrength, psi 3319 3221 95% Confidence Interval 99 50 Ultimate Elongation, % 301 375 95% Confidence Interval 15 7 Aged Mechanical Properties: Aged 100% Modulus Strength, psi 2719 2249 Aged Ultimate TensileStrength, psi 162 85 Ultimate TensileStrength, psi 3082 3094 95% Confidence Interval 105 101 Ultimate Elongation, % 206 299 95% Confidence Interval 32 12 Weight Loss, Wt % 10 6.9 95% Confidence Interval 1.03 0.61 Retained Properties: Retained 100% Modulus Strength, % 135 134 95% Confidence Interval 0.7 0.6 Retained Tensile Strength, % 93 96 95% Confidence Interval 0.3 0.3 Retained Elongation, % 68 80 95% Confidence Interval 1.7 0.8 Other: Carbon Volatility (24 hours at 70 C.) Mean (3 specimens) 0.5 0.5 95% Confidence Interval 0 0.1 Low Temperature Bell Brittleness (Tb), C. 1.8 30.2 95% Confidence Interval 2 2

(33) TABLE-US-00006 TABLE 5 Mechanical Properties Comparison TSR # 09-021 Plastisols Sample ID: F G Formulations: PVC Plastisol (GEON 124A) 100 100 iso-decyl benzoylbenzoate 70 Jayflex DINP 70 (ESO) Drapex 6.8 2 2 (Ca/Zn Stabilizer) Mark 1221 2.5 2.5 Sample Prep & Observations: Samples were fused on WM Oven at 190 C. and molded at 340 F. to thickness. Original Mechanical Properties Shore A Hardness (15 sec.) 61 63 95% Confidence Interval 0.4 0.8 100% Modulus Strength, psi 980 975 95% Confidence Interval 24 14 Ultimate TensileStrength, psi 2389 2318 95% Confidence Interval 74 90 Ultimate Elongation, % 334 384 95% Confidence Interval 67 12 Aged Mechanical Properties: Aged 100% Modulus Strength, psi 1794 1379 Aged Ultimate TensileStrength, psi 173 29 Ultimate TensileStrength, psi 2460 2114 95% Confidence Interval 209 40 Ultimate Elongation, % 232 253 95% Confidence Interval 27 9 Weight Loss, Wt % 14 11 95% Confidence Interval 0.43 0.28 Retained Properties: Retained 100% Modulus Strength, % 183 141 95% Confidence Interval 1.4 0.7 Retained Tensile Strength, % 103 91 95% Confidence Interval 0.5 0.3 Retained Elongation, % 70 66 95% Confidence Interval 1.6 0.7

(34) TABLE-US-00007 TABLE 6 Mechanical Properties Comparison TSR # 09-027 Wet-Blends Sample ID H I Formulations: Oxy 240 100 100 iso-nonyl benzoylpropionate 50 iso-nonyl benzoylbenzoate 50 Drapex 6.8 (ESO) 2.5 2.5 Mark 1221 (CaZn Stabilizer) 2.5 2.5 Stearic Acid (External Lubricant) 0.3 0.3 Sample Prep & Observations Samples were milled at 330 F. Moderate Low and molded at 340 F. smoking; smoking; High odor low odor Original Mechanical Properties Shore A Hardness (15 sec.) 73 79 95% Confidence Interval 0.64 0.80 Shore D Hardness (15 sec.) 21 27 95% Confidence Interval 0.14 0.14 100% Modulus Strength, psi 1276 2011 95% Confidence Interval 35 32 Ultimate TensileStrength, psi 3148 3403 95% Confidence Interval 122 129 Ultimate Elongation, % 357 296 95% Confidence Interval 13 20 Aged Mechanical Properties: Aged 100% Modulus Strength, psi 1640 2146 95% Confidence Interval 109 30 Ultimate TensileStrength, psi 3131 3211 95% Confidence Interval 99 123 Ultimate Elongation, % 309 279 95% Confidence Interval 23 16 Weight Loss, Wt % 5 1 95% Confidence Interval 1.4 0.4 Retained Properties: Retained 100% Modulus Strength, % 129 107 95% Confidence Interval 0.86 0.33 Retained Tensile Strength, % 99 94 95% Confidence Interval 0.40 0.38 Retained Elongation, % 87 94 95% Confidence Interval 1.4 1.7 Low Temperature Clash Berg (Tf), C. 20 0.2 95% Confidence Interval 2.4 1.6

(35) The plasticizers according to the invention may also be used with vinyl chloride-type resins, polyesters, polyurethanes, ethylene-vinyl acetate copolymer, rubbers, acrylics, polymer blends such as of polyvinyl chloride with an ethylene-vinyl acetate copolymer or polyvinyl chloride with a polyurethane or ethylene-type polymer.

(36) All patents and patent applications, test procedures (such as ASTM methods, UL methods, and the like), and other documents cited herein are fully incorporated by reference to the extent such disclosure is not inconsistent with this invention and for all jurisdictions in which such incorporation is permitted.

(37) When numerical lower limits and numerical upper limits are listed herein, ranges from any lower limit to any upper limit are contemplated. While the illustrative embodiments of the invention have been described with particularity, it will be understood that various other modifications will be apparent to and can be readily made by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the examples and descriptions set forth herein but rather that the claims be construed as encompassing all the features of patentable novelty which reside in the present invention, including all features which would be treated as equivalents thereof by those skilled in the art to which the invention pertains.

(38) The invention has been described above with reference to numerous embodiments and specific examples. Many variations will suggest themselves to those skilled in this art in light of the above detailed description. All such obvious variations are within the full intended scope of the appended claims.