Low emissions scorch inhibitor for polyurethane foam

Abstract

Disclosed is a scorch inhibitor composition comprising (A) one or more 2,2,4-trimethyl-1,2-dihydroquinoline compound, (B) one or more lactone, (C) one or more phenolic compound, (D) optionally one or more tocopherol, and (E) optionally one or more phosphite compound.

Claims

1. A foam composition formed from 0.05 to 4 pbw of a scorch inhibitor composition in combination with a polyether polyol or a polyester or blend thereof at 100 pbw, wherein the scorch inhibitor composition is a liquid and comprises: (A) a 2,2,4-trimethyl-1,2-dihydroquinoline compound, present at 1-30 weight % of the scorch inhibitor composition, (B) a liquid polymeric lactone composition consisting of liquid lactones and/or lactone derivatives compounded to form a liquid, present at 1-25 weight % of the scorch inhibitor composition, (C) a phenolic component in liquid form present at 5-80% of the scorch inhibitor composition, being a compound or blend of compounds chosen from the group consisting of (i) (3,5-bis(1,1-di-methylethyl)4-hydroxyphenyl) (C7-C9) alkyl (branched) propanoate; (ii) 3,5-bis(1,1-dimethylethyl)-4-hydroxy-benzenepropanoic acid, C13-15-branched and linear alkyl esters; (iii) esters of -(3,5-di-tert-butyl-4-hydroxylphenyl) propionic acid with mono- or polyhydric alcohols; and (iv) octyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate, (D) optionally a tocopherol, and (E) optionally a phosphite compound.

2. The foam composition of claim 1, wherein component (A) of the scorch inhibitor composition is chosen from the group consisting of 1,2-dihydro-2,2,4-trimethylquinoline polymer having 2 to 6 monomer units, non-aromatized 1,2-dihydro-2,2,4-trimethylquinoline composed of dimer and trimer units, 6-dodecyl-2,2,4-2,2,4-trimethyl-1,2-dihydroquinoline, 6-lauryl-2,2,4-trimethyl-1H-quinoline, 6-ethoxy-2,2,4-trimethyl-1-2-dihydroquinoline, polymerized 1,2-dihydro-2,2,4-trimethylquinoline, and a mixture thereof.

3. The foam composition of claim 1, wherein one or both of component (D) and component (E) is present and, a. Component (D), when present, comprises the tocopherol chosen from the group consisting of -tocopherol, -tocopherol, -tocopherol, -tocopherol and mixtures thereof, at a 1-30 weight % of the scorch inhibitor composition; and b. component (E), when present, comprises the phosphite compound chosen from the group consisting of a triphenyl phosphite, a diphenyl alkyl phosphite, a phenyl dialkyl phosphite, a tris(nonylphenyl) phosphite, a trilauryl phosphite, a trioctadecyl phosphite, a distearyl pentaerythritol diphosphite, a tris(2,4-di-tert-butylphenyl) phosphite, a diisodecyl pentaerythritol diphosphite, a bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, a bis(2,6-di-tert-butyl-4-methylphenyl)-pentaerythritol diphosphite, a diisodecyloxypentaerythritol diphosphite, a bis(2,4-di-tert-butyl-6-methylphenyl)pentaerythritol,and a mixture thereof, at 1-25 weight % of the scorch inhibitor composition.

4. The foam composition of claim 1, wherein the scorch inhibitor composition consists essentially of a blend of components (A)-(E) or consists of a blend of components (A)-(E).

5. The foam composition of claim 1, which consists essentially of the scorch inhibitor composition and polyether polyol or a polyester or blend thereof, or which consists of the scorch inhibitor composition and polyether polyol or a polyester or blend thereof.

6. The foam composition of claim 1, wherein component (A) present at 1-25 weight % of the scorch inhibitor composition.

7. The foam composition of claim 1, wherein component (A) present at 1-20 weight % of the scorch inhibitor composition.

8. The foam composition of claim 1, wherein component (B) present at 1-20 weight % of the scorch inhibitor composition.

9. The foam composition of claim 1, wherein component (C) present at 5-70 weight % of the scorch inhibitor composition.

10. The foam composition of claim 1, wherein component (C) present at 25-80 weight % of the scorch inhibitor composition.

11. The foam composition of claim 1, wherein component (D) is present at 0-20 weight % of the scorch inhibitor composition.

12. The foam composition of claim 1, wherein component (D) is present at 0-25 weight % of the scorch inhibitor composition.

13. The foam composition of claim 1, wherein component (E) is present at 0-20 weight % of the scorch inhibitor composition.

14. The foam composition of claim 1, wherein component (A) is present at 10-20 weight % of the scorch inhibitor composition, component (B) is present at 1-10 weight % of the scorch inhibitor composition, and component (C) is present at 20-50 weight % of the scorch inhibitor composition.

15. The foam composition of claim 1, wherein the scorch inhibitor composition comprises: (A) a polymerized 2,2,4-trimethyl-1,2-dihydroquinoline compound, (B) a liquid polymeric lactone composition consisting of liquid lactones and/or lactone derivatives compounded to form a liquid, (C) a phenolic component in liquid form, being a compound or blend of compounds chosen from the group consisting of (3,5-bis(1,1-di-methylethyl)4-hydroxyphenyl) (C7-C9) alkyl (branched) propanoate; and 3,5-bis(1,1-dimethylethyl)-4-hydroxy-benzenepropanoic acid, C13-15-branched and linear alkyl esters.

16. A method for reducing scorch or for lowering emission profile during polyurethane foam production, comprising a step of adding 0.05 to 4 pbw of a scorch inhibitor composition, to polyether polyol or a polyester or blend thereof at 100 pbw wherein the scorch inhibitor composition is a liquid and comprises: (A) a 2,2,4-trimethyl-1,2-dihydroquinoline compound, present at 1-30 weight % of the scorch inhibitor composition, (B) a liquid polymeric lactone composition consisting of liquid lactones and/or lactone derivatives compounded to form a liquid, present at 1-25 weight % of the scorch inhibitor composition, (C) a phenolic component in liquid form present at 5-80% of the scorch inhibitor composition, being a compound or blend of compounds chosen from the group consisting of (i) 3,5-bis(1,1-di-methylethyl)4-hydroxyphenyl) (C7-C9) alkyl (branched) propanoate; (ii) 3,5-bis(1,1-dimethylethyl)-4-hydroxy-benzenepropanoic acid, C13-15-branched and linear alkyl esters (iii) esters of -(3,5-di-tert-butyl-4-hydroxylphenyl) propionic acid with mono- or polyhydric alcohols; (iv) octyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate, (D) optionally a tocopherol, and (E) optionally a phosphite compound.

Description

EXAMPLES

Example 1

(1) Preparation of the Blend and Evaluation

(2) Typically a blend of the aforementioned components is prepared by adding solid components to a heated blend (50-90 C.) of liquid components. The mixture is then charged into a polyether polyol (or polyester or blend). Commercially available polyether polyols have properties such that they are typically transparent, viscous liquids with a range of functionalities of about 3, a hydroxyl number range of approximately 30-56, and glycine initiated with an ethylene oxide-propylene oxide (RD/PO) ratio of 10/90. The polyether polyol, antioxidant blend is considered a finished product to polyether polyol producers and can be used to prepare polyurethane foam products as described earlier. The finished product is preferably characterized by no or minimal discoloration caused by the antioxidant blend. The charge level of the inventive blend in the polyether polyol may vary from 0.05 to 2 pbw, or up to 4 pbw. A typical foam formula used for VDA-278 testing is low water (3-4.5 pbw) and can conveniently be poured into a common cakebox as often done in the industry for testing.

(3) TABLE-US-00002 TABLE 1 Commercial example of Foam formula Foam formula ingredient ingredient pbw VORANOL Triol polyol 100 Polyether Polyols Water Water 4.3 Niax Silicone L5770 Silicone 0.9 Niax* Catalyst A-33 Amine catalyst 0.17 Dabco T9 Tin catalyst 0.25 Scorch inhibitor Cited in text (preferred 0.05-4 blends) VORANATE T-80 Toluene diisocyanate 54.91 TDI

(4) Foams prepared are sliced and swatches are conditioned for a seven day period of time prior following VDA-278 protocol.

Example 2

(5) TABLE 2 below shows Brightmeter Color Readings (L, a, b) for SCORCH test of Blends #2, 3, 6 and 7, trialed against an incumbent scorch inhibitor formula (PUR 67). Here, MA and ResinD are forms of polymerized 1,2-dihydro-2,2,4-trimethylquinoline (component (A)). 1315 refers to Anox 1315 (component (C)). 1135 refers to Songox 1135 (component (C)). VitaE refers to vitamin E (component (D)). AOX1 refers to Milliguard AOX1 (component (B)), a lactone based antioxidant made by the Milliken Co. (see, e.g., Xia).

(6) Polyurethane foam formula used: Voranol 9137ca (Dow) 100 parts, Water 6 parts, Momentive L5570 Silicone 1.1 parts, Momentive A33 Amine 0.12 parts, Air Products T9 Tin Cat 0.2 parts, Voranate TDI (Dow) 78.0 parts.

(7) TABLE-US-00003 TABLE 2 Blend#6 Blend#2 Blend#3 10% ResinD (A) Blend#7 10% MA (A) 10% ResinD (A) 40% 1315 (C) 10% ResinD (A) 30% 1315 (C) 40% 1315 (C) 20% 1135 (C) 20% 1315 (C) 50% VitaE (D) 40% VitaE (D) 20% VitaE (D) 50% VitaE (D) PUR 67 10% AOX1(B) 10% AOX1(B) 10% AOX1 (B) 10% AOX1 (B) 7:20@30% L 82.71 81.88 81.15 81.91 83.03 A .21 .69 .54 .70 .73 B .00 3.95 3.84 4.1 3.99 L 66.37 76.62 81.78 68.47 65.06 A 7.95 0.81 2.57 6.41 9.01 B 33.24 23.96 15.85 31.52 34.23 E 38.22 25.04 16.35 35.50 39.89 Cream/Rise/Temp 24/81/416 23/80/395 24/81/388 22/82/418 22/78/429

Example 3

Light Fade Study

(8) TABLE 3 below shows Brightmeter Color Readings (L, a, b) for LIGHT EXPOSURE test of Blends #10-14, trialed against PUR 67.

(9) TABLE-US-00004 TABLE 3 Blend#10 Blend#11 Blend#12 Blend#13 Blend#14 15% ResinD (A) 15% ResinD (A) 19% ResinD (A) 20% ResinD 10% ResinD (A) 40% 1315 (C) 40% 1315 (C) 40% 1315 (C) (A) 40% 1315(C) 35% VitaE (D) 40% VitaE (D) 40% VitaE (D) 40% 1315 (C) 40% VitaE (D) PUR 67 10% AOX1 (B) 5% AOX1 (B) 1% AOX1 (B) 40% VitaE (D) 10% AOX1(B) 7:20 @30% L 81.49 80.32 78.83 79.85 80.85 81.09 A .48 .69 .70 .63 .63 .58 B .26 .48 .40 .29 .08 0.16 5 Days L 79.45 78.22 77.31 78.61 78.22 78.81 A .15 .12 .15 .17 .21 .16 B 9.31 9.11 8.86 9.74 9.56 9.08 E 9.79 9.83 9.40 10.12 9.85 9.22 7 Days L 78.48 77.77 76.70 77.65 77.30 78.07 A .43 .45 .47 .53 .51 .31 B 11.15 11.67 11.35 12.09 11.85 11.04 E 11.80 12.42 11.94 12.57 12.29 11.29

Example 4

Scorch Test with vitamin E removed

(10) TABLE 4 below shows Brightmeter Color Readings (L, a, b) for SCORCH test of Blends #18, 19 and 20, trialed against PUR 67.

(11) TABLE-US-00005 TABLE 4 Blend#20 Blend#18 20% ResinD (A) 20% ResinD (A) Blend#119 75% 1315 (C) 75% 1315 (C) 20% ResinD (A) 5% VitaE (Cargill PUR 67 5% AOX1 (B) 80% 1315 (C) Tocopherols) (D) PUR 67 Repeat Apr. 25, 2016 7:20@30% L 82.59 84.08 84.16 83.25 A .21 .07 .01 .02 B .95 .85 .66 1.16 L 65.51 62.80 65.74 68.38 A 8.36 10.17 8.65 6.86 B 34.13 34.95 34.79 32.72 E 39.45 41.82 39.99 36.69 Cream/Rise/Temp 21/79/437 21/78/429 20/73/423 20/72/423 Apr. 26, 2016 6:30@30% L 83.18 83.16 83.12 83.68 A .14 .35 .16 .19 B .24 .68 .69 .34 L 66.34 68.18 76.16 66.72 A 7.72 6.88 .00 7.31 B 32.95 32.76 22.08 32.43 E 37.93 36.82 23.36 37.22 Cream/Rise/Temp 19/85/420 23/88/421 23/88/404 22/85/434 Jun. 9, 2016 7:30@30% L 82.58 82.91 82.45 82.06 82.66 A .05 .13 .11 .28 .06 B .12 .85 .49 1.45 .32 L 81.72 67.89 57.54 67.63 83.00 A .54 5.91 11.39 5.66 .97 B .99 30.84 34.59 30.14 2.71 E 2.01 35.06 44.62 34.52 3.15 Cream/Rise/Temp 23/103/396 20/93/412 21/88/433 17/82/410 1886/388

Example 5

Scorch Test Comparing Prior Art and Individual Components with Inventive Blend

(12) Table 5 below shows Brightmeter Color Readings (L, a, b) for SCORCH test for additional blends, including inventive Blend B (Blend#26) and Blend C (Blend#25).

(13) TABLE-US-00006 Blend B (Blend#26) Blend C (Blend#25) (A)-20% polymerized 1,2-dihydro- (A) 20% polymerized 1,2-dihydro- 2,2,4-trimethylquinoline 2,2,4-trimethylquinoline (C) 50% Anox 1315 (C) 35% Anox 1315 (C) 20% Songox 1135 (C) 35% Songox 1135 (B) 10% AOX1 (B) 10% AOX1

(14) TABLE-US-00007 TABLE 5 Blend B Blend C Anox 1315 Songnox 1135 (C) (0.25) (0.25) (C) (0.25) 20% 20% Resin D (A) (0.25) (3,5-bis(1,1- ResinD ResinD (0.25) 3,5-bis(1,1- dimethyl)4- 50% 1315 35% 1315 Polymerized dimethylethyl)- hydroxyphenyl) 20% 1135 35% 1135 1,2-dihydro- 4-hydroxy- (C7-C9) PUR 67 AOX1 10% 10% 2,2,4- benzenepropanoic alkyl(branched) (0.25) (0.25) AOX1 AOX1 trimethylquinoline acid propionate 7:50@30% L 81.41 81.87 82.88 80.62 83.88 81.20 81.84 A .20 .83 .26 .33 .14 .66 .26 B 1.09 3.91 2.03 2.21 2.18 2.15 .92 L 82.13 82.20 81.81 82.22 60.23 72.07 77.90 A .84 1.11 1.33 1.18 9.95 3.00 .38 B 3.01 4.41 4.95 3.28 35.01 23.87 12.90 E 3.53 4.89 5.54 3.86 43.13 26.65 14.13 Cream/Rise/Temp 16/79/400 18/85/406 17/83/393 18/87/404 17/90/416 17/85/395 17/95/398 8/12 3.53 4.89 5.54 3.86 43.13 26.65 14.13 8/11 1.68 2.67 4.72 10.23 14.59 5.53 5.16 8/5 4.40 5.97 1.83 8.66 48.94 32.62 11.94 AVERAGE 3.20 4.51 4.03 7.58 35.55 21.60 10.41 (3xs) Foam: Voranol 9137ca (DOW) 100 parts, Water 6 parts, Momentive L5570 Silicone 1.1 parts, Momentive A33 Amine 0.12 parts, Air Products T9 Tin Cat 0.2 parts, Voranate TDI (Dow) 78.0 parts.

Example 6

Emissions Test

(15) The inventive blends adequately protected against scorch development in polyurethan slabstock foam and give low VOC/fog emissions as detected in VDA-278 against incumbent product PUR 67. The test concerns two heat treatments of a swatch of foam followed by analysis. The first heat treatment (90 C. for 30 minutes) collects lower boiling components (VOC) and the second heat treatment (thermal desorption at 120 C. for 60 minutes) collects higher boiling components (FOG). The measurement of volatile compounds (VOC/FOG) is according to VDA 278 (Daimler Chrysler-PB VWL 709). An average is presented for ease of comparison representing two values from the center and edge of the foam block. The specimens (see Example 5) results present total VOC, Fog, and Total AO for three trial foams containing inventive blends and a control consisting of PUR 67. Total emissions are reduced for all three blends but as (3,5-bis(1,1-di-methylethyl)4-hydroxy-phenyl) (C7-C9) alkyl(Branched) propanoate is reduced in the scorch inhibitor blends the total emissions value drops (c. A<B<C) yet all blends showed less than half the total emissions of the Control blend (PUR 67). It is also observed that the other components while detected (or derivatives of them) were at low levels.

(16) TABLE-US-00008 TABLE 6 Blend B Blend C Blend A 20% ResinD (A) ResinD (A) 20% ResinD (A) 50% 1315 (C) 35% 1315 (C) Average center 70% ANOX (C) 20% 1135 (C) 35% 1135 (C) and edge Control Blend 10% AOX1 (B) 10% AOX1 (B) 10% AOX1 (B) Total VOC 0.8 5.1 5.6 4.9 Total Fog 164 44 59 83 Total emissions 165 49 65 88 Antioxidant levels detected VDA-278
Discussion

(17) The present invention uses the lactone mentioned in Xia but improves upon scorch performance showing a synergistic effect, as seen by comparison of AOX1 versus B. This (AOX1) demonstrates prior art concerning a low VOC scorch inhibitor.

(18) As demonstrated in the Examples above, a fraction of the prior art material ( 1/10.sup.th of AOX1 polymeric lactone) is required in the present composition to achieve similar performance of prior art material. Blend B shows greater reduced scorch compared against prior art AOX1. The same blend outperforms all individual components.

(19) Polymerized 1,2-dihydro-2,2,4-tirmethylquinoline is not a particularly useful antioxidant for scorch protection. Two problems were observed during development of the present inventive blends. Firstly it is a solid thereby needing to be dissolved for further use if it had any further use as a slab stock polyether polyol stabilizer. Secondly, polymerized 1,2-dihydro-2,2,4-tirmethylquinoline was found to be a poor scorch inhibitor in polyurethane foam. (Example 5). However, once dissolved in the inventive composition both problems were overcome.

Example 7

Additional Scorch Exposure Test

(20) TABLE-US-00009 TABLE 7 20% MA (A) 20% MA (A) 33% 1315 33% 2920* 20% MA(A) (C) 37% VitaE 33% 1520** PUR 68 37% VitaE (D) (D) 37% VitaE (D) Vanox 945 PUR 68 Repeat 10% AOX1 (B) 10% AOX1 (B) 10% AOX1 (B) 7:50@30% L 81.95 81.77 81.97 81.64 82.65 81.75 A -.00 -.11 -.02 -.05 -.03 -.12 B .64 .89 .63 .59 .76 1.33 L 76.21 82.05 82.49 82.44 82.92 82.37 A .06 -2.27 -1.48 -3.51 -3.29 -3.01 B 20.85 8.90 4.80 9.73 7.77 8.54 E 27.93 9.50 5.32 10.63 8.71 9.31 Cream/ 25/85/384 25/86/372 22/87/382 21/85/381 23/87/375 22/82/380 Rise/Temp *IRGANOX 1520 (2-Methyl-4,6-bis(octylsulfanylmethyl)phenol)