Silicone-based defoamer composition

Abstract

Provided is a silicone anti-foaming agent composition that not only has superior anti-foaming speed but also in which anti-foaming performance is not reduced even when used repeatedly or over a long period. The composition comprises: a polyorganosiloxane polymer crosslinked product having a polyoxyalkylene group, which includes: moiety structure (I): -R.sup.1-(R.sup.2.sub.2SiO).sub.d-R.sup.1(where R.sup.1 represents an alkylene group bonded to a silicon atom on the polysiloxane chain, R.sup.2 represents a monovalent hydrocarbon group, and d is 200 to 1000); and moiety structure (II): (C.sub.eH.sub.2e)O(EO).sub.x-(PO).sub.y-(BO).sub.z-R.sup.3 (where a single bond on the left end is bonded to a silicon atom on the polysiloxane chain, R.sup.3 represents a hydrogen atom, an alkyl group, an aryl group or an acyl group, e is 2 to 10, (x+y+z) is 40 to 100, x is 15 to 50, y is 15 to 50, and z is 0 to 50).

Claims

1. A silicone anti-foaming agent composition, comprising a polyorganosiloxane polymer crosslinked product having a polyoxyalkylene group, which includes: moiety structure (I):
R.sup.1(R.sup.2.sub.2SiO).sub.dR.sup.1 where R.sup.1 represents an alkylene group having 2 to 20 carbon atoms bonded to a silicon atom on the polysiloxane chain, R.sup.2 represents a monovalent hydrocarbon group, and d is a number in the range of 200 to 1,000; and moiety structure (II):
(C.sub.eH.sub.2e)O(EO).sub.x(PO).sub.y(BO).sub.zR.sup.3 where EO represents an ethyleneoxy unit expressed by C.sub.2H.sub.4O, PO represents a propyleneoxy unit expressed by C.sub.3H.sub.6O, BO represents a butyleneoxy unit expressed by C.sub.4H.sub.8O, a single bond on the left end is bonded to a silicon atom on the polysiloxane chain, R.sup.3 represents a hydrogen atom, an alkyl group, an aryl group or an acyl group, e is a number ranging from 2 to 10, (x+y+z) is a number ranging from 40 to 100, x is a number ranging from 15 to 50, y is a number ranging from 15 to 50, and z is a number ranging from 0 to 50.

2. The silicone anti-foaming agent composition according to claim 1, wherein d in moiety structure (I) is a number ranging from 250 to 900.

3. The silicone anti-foaming agent composition according to claim 1, wherein in moiety structure (II), x is a number ranging from 20 to 40, y is a number ranging from 20 to 40, and z is zero.

4. The silicone anti-foaming agent composition according to claim 1, wherein the polyorganosiloxane polymer crosslinked product having a polyoxyalkylene group is expressed by the following structural formula: ##STR00008## where a is a number ranging from 10 to 200, (b+c) is a number ranging from 2 to 50, b and c are each a number ranging from 1 or more, EO and PO are as described above, R represents a hydrogen atom, an alkyl group, an aryl group or an acyl group, and d, x and y are as defined in the moiety structures (I) and (II).

5. The silicone anti-foaming agent composition according to claim 1, further comprising a silicone-based anti-foaming agent oil compound, wherein the silicone-based anti-foaming agent oil composition comprises: (A) an essentially hydrophobic organopolysiloxane having a viscosity of 10 to 100,000 mPa.Math.s at 25 C.: 20 to 80 parts by mass; (B) a hydrophobic organopolysiloxane or a cyclic organopolysiloxane containing silanol groups at least at both ends: 20 to 80 parts by mass; (C) a silane or silane condensation product: 1 to 10 parts by mass; and (D) a fine powder silica having a specific surface area of 50 m.sup.2/g or more: 2 to 10 parts by mass; wherein the total amount of (A) and (B) is 100 parts by mass.

6. The silicone anti-foaming agent composition according to claim 5, wherein component (B) includes: (B1) a hydrophobic organopolysiloxane containing a silanol group at both ends and having a viscosity of 1000 to 10,000,000 mPa.Math.s; and (B2) a hydrophobic organopolysiloxane or cyclic siloxane containing silanol groups at both ends and having a viscosity of 1 to 1000 mPa.Math.s.

7. The silicone anti-foaming agent composition according to claim 5, wherein the molar ratio of component (B) relative to the total amount of component (A) and component (B) is 0.7 or more.

8. The silicone anti-foaming agent composition according to claim 6, wherein the molar ratio of component (B1) relative to the total amount of component (A) and component (B1) is 0.2 or more.

9. The silicone anti-foaming agent composition according to claim 5, wherein the silicone-based anti-foaming agent oil composition is emulsified by the polyorganosiloxane polymer crosslinked product having a polyoxyalkylene group.

10. The silicone anti-foaming agent composition according to claim 1, wherein the viscosity of the silicone-based anti-foaming agent oil composition at 25 C. is 10,000 to 1,000,000 mPa.Math.s.

11. The silicone anti-foaming agent composition according to claim 9, wherein the emulsion particle diameter is 0.1 to 10 m.

12. A metalworking oil comprising the silicone anti-foaming agent composition according to claim 1.

Description

EXAMPLES

(1) The present invention will be described in detail below based on examples, but the present invention is not limited to the following examples.

(2) [Viscosity measurement]

(3) Using a rotational viscometer (manufactured by SHIBAURA SEMTEK CO., LTD., product name: Vismetron VDA-2), measurement was performed on rotor No. 4 at a rotational speed of 12 rpm.

(4) [Measurement of average particle diameter]

(5) A self-emulsifying compound was dispersed in water and measured using a laser diffraction particle diameter distribution analyzer (LS-230 of Beckman Coulter) and the median diameter (particle diameter corresponding to 50% of the cumulative distribution, 50% particle diameter) was used as the average particle diameter.

(6) [Evaluation of anti-foaming performance]

(7) NS Cut S-20 (soluble-type water-soluble cutting liquid, 20% active component, manufactured by NS Chemical Co., Ltd.) diluted 4 times with tap water and temperature-controlled to 23 C. was used as a foaming liquid used for antifoaming performance evaluation. The viscosity of the foaming liquid at this time was 3.5 mPa.Math.s. The anti-foaming agent to be evaluated was added at 25 ppm based on solid content.

(8) 400 g of the foaming liquid described above was added to a 1000 mL tall beaker, and stirred at 8000 rpm for 10 minutes using a homomixer (manufactured by Primix Co., Ltd., model HV-M) to cause foaming. Herein, the height of a baffle was 10 cm from the bottom of the homomixer and 11 cm from the bottom of the flask. After stopping the stirring, a foam layer was formed on an upper layer of a liquid portion, and a change in the thickness of the foam layer over time was measured. The time required for the thickness of the foam layer to decrease to 4 mm was defined as t (minutes), and evaluations were made as shown in the table below.

(9) TABLE-US-00001 TABLE 1 Evaluation of anti-foaming performance Anti-foaming performance Time t < 3 3 t < 5 5 t < 6 X t 6

(10) In order to confirm the retention of the anti-foaming performance, this operation was repeated four times and the anti-foaming performance was evaluated each time.

(11) [Production Example 1]

(12) 12.59 g of component (a) of a straight-chain organopolysiloxane expressed by the following chemical formula 1, where j=110 and k=10, and 4.57 g of component (b) of a straight-chain organopolysiloxane expressed by the following chemical formula 2, where m=290, were heated and mixed at 60 C. After mixing uniformly, 0.002 g of chloroplatinic acid and 0.15 g of isopropyl alcohol were mixed therein and allowed to react at 60 C. for 3 hours, and a transparent viscous liquid was obtained. 0.01 g of sodium acetate and 82.84 g of ethylene oxide, 22 mol of propylene oxide, and 22 mol of hydrogen-terminated allyl polyether were added to the obtained viscous liquid and reacted for 3 hours while maintaining the temperature at 80 to 90 C. After the reaction, the isopropyl alcohol in the viscous liquid was removed by heating at 80 C. for 1 hour under reduced pressure. A brown viscous liquid was obtained.

(13) ##STR00007##
[Production Example 2]

(14) 12.20 g of component (a) of a straight-chain organopolysiloxane expressed by chemical formula 1 described above, where j=110 and k=10, 7.51 g of component (b) of a straight-chain organopolysiloxane expressed by chemical formula 2 described above, where m=493, and 20.00 g of toluene were heated and mixed at 60 C. After mixing uniformly, 0.002 g of chloroplatinic acid and 0.15 g of isopropyl alcohol were mixed therein and allowed to react at 60 C. for 3 hours, and a transparent viscous liquid was obtained. 0.01 g of sodium acetate and 80.29 g of ethylene oxide: 22 mol of propylene oxide: and 22 mol of hydrogen-terminated allyl polyether were added to the obtained viscous liquid and reacted for 3 hours while maintaining the temperature at 80 to 90 C. After the reaction, the isopropyl alcohol and toluene in the viscous liquid were removed by heating at 100 C. for 3 hours under reduced pressure. A brown viscous liquid was obtained.

(15) [Production Example 3]

(16) 11.71 g of component (a) of a straight-chain organopolysiloxane expressed by chemical formula 1 described above, where j=110 and k=10, 11.19 g of component (b) of a straight-chain organopolysiloxane expressed by chemical formula 2 described above, where m=766, and 12.82 g of toluene were heated and mixed at 60 C. After mixing uniformly, 0.002 g of chloroplatinic acid and 0.15 g of isopropyl alcohol were mixed therein and allowed to react at 60 C. for 3 hours, and a transparent viscous liquid was obtained. 0.01 g of sodium acetate and 77.10 g of ethylene oxide: 22 mol of propylene oxide: and 22 mol of hydrogen-terminated allyl polyether were added to the obtained viscous liquid and reacted for 3 hours while maintaining the temperature at 80 to 90 C. After the reaction, the isopropyl alcohol and toluene in the viscous liquid were removed by heating at 100 C. for 3 hours under reduced pressure. A brown viscous liquid was obtained.

Comparative Production Example 1

(17) 21.46 g of component (a) of a straight-chain organopolysiloxane expressed by chemical formula 1 above, where j=110 and k=10, and 4.58 g of component (b) of a straight-chain organopolysiloxane expressed by chemical formula 2 above, where m=179, were heated and mixed at 60 C. After mixing uniformly, 0.002 g of chloroplatinic acid and 0.15 g of isopropyl alcohol were mixed therein and allowed to react at 60 C. for 3 hours, and a transparent viscous liquid was obtained. 0.01 g of sodium acetate and 73.80 g of ethylene oxide: 18 mol of propylene oxide: and 18 mol of hydrogen-terminated allyl polyether were added to the obtained viscous liquid and reacted for 3 hours while maintaining the temperature at 80 to 90 C. After the reaction, the isopropyl alcohol in the viscous liquid was removed by heating at 80 C. for 1 hour under reduced pressure. A brown viscous liquid was obtained.

Comparative Production Example 2

(18) 12.81 g of component (a) of a straight-chain organopolysiloxane expressed by chemical formula 1 above, where j=110 and k=10, and 2.88 g of component (b) of a straight-chain organopolysiloxane expressed by chemical formula 2 above, where m=179, were heated and mixed at 60 C. After mixing uniformly, 0.002 g of chloroplatinic acid and 0.15 g of isopropyl alcohol were mixed therein and allowed to react at 60 C. for 3 hours, and a transparent viscous liquid was obtained. 0.01 g of sodium acetate and 84.31 g of ethylene oxide: 22 mol of propylene oxide: and 22 mol of hydrogen-terminated allyl polyether were added to the obtained viscous liquid and reacted for 3 hours while maintaining the temperature at 80 to 90 C. After the reaction, the isopropyl alcohol in the viscous liquid was removed by heating at 80 C. for 1 hour under reduced pressure. A brown viscous liquid was obtained.

(19) TABLE-US-00002 TABLE 2 Amounts of each component used in Production Examples 1 to 3 and Comparative Production Examples 1 and 2 (unit: g) Table 2-1 Production Production Production Example 1 Example 2 Example 3 Straight-chain 12.59 12.20 11.71 organopolysiloxane expressed by chemical formula 1 (j = 110, k = 10) Straight-chain 4.57 organopolysiloxane expressed by chemical formula 2 (m = 290) Straight-chain 7.51 organopolysiloxane expressed by chemical formula 2 (m = 493) Straight-chain 11.19 organopolysiloxane expressed by chemical formula 2 (m = 766) Straight-chain organopolysiloxane expressed by chemical formula 2 (m = 179) Toluene 20.00 23.00 Isopropyl alcohol 0.15 0.15 0.15 Chloroplatinic acid 0.002 0.002 0.002 Allyl E0/P0 = 22/22 82.84 80.29 77.10 polyether E0/P0 = 18/18 EO-PO Sodium acetate 0.01 0.01 0.01 Table 2-2 Com- parative Comparative Production Production Example 1 Example 2 Straight-chain 21.46 12.81 organopolysiloxane expressed by chemical formula 1 (j = 110, k = 10) Straight-chain organopolysiloxane expressed by chemical formula 2 (m = 290) Straight-chain organopolysiloxane expressed by chemical formula 2 (m = 493) Straight-chain organopolysiloxane expressed by chemical formula 2 (m = 766) Straight-chain 4.58 2.88 organopolysiloxane expressed by chemical formula 2 (m = 179) Toluene Isopropyl alcohol 0.15 0.15 Chloroplatinic acid 0.002 0.002 Allyl E0/P0 = 22/22 84.31 polyether E0/P0 = 18/18 73.80 EO-PO Sodium acetate 0.01 0.01
[Silicone-based anti-foaming agent oil compound #1]

(20) Silicone-based anti-foaming agent oil compound #1 was manufactured by the following method. In other words, 59.10 parts by mass of polydimethylsiloxane blocked with a trimethylsilyl group (viscosity of 1,000 mPa.Math.s at 25 C.), 30.60 parts by mass of polydimethylsiloxane blocked with a silanol group (viscosity of 12,500 mPa.Math.s at 25 C.), and 3.06 parts by mass of polyethyl silicate (Cilbond 50 manufactured by Evonik) were placed in a three neck flask with a capacity of 1 L provided with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas supply, while stirring, and the temperature was raised to 110 C. A mixture of 1.54 parts by mass of premixed potassium dimethylsilanolate, 5.15 parts by mass of polydimethylsiloxane blocked with a trimethylsilyl group (viscosity of 1,000 mPa.Math.s at 25 C.), and 0.08 parts by mass of ethanol was added at 110 C. and stirring was continued for 30 minutes at 110 C. Next, silica (Aerosil 200, specific surface area: 200 m.sup.2/g, manufactured by Evonik) was added, and then homogeneously dispersed using a homomixer for 30 minutes while heating at 110 C. A mixture of 0.02 parts by mass of polyether-modified silicone 501W and 0.13 parts by mass of ion exchanged water was added. After stirring, 5.15 parts by mass of polydimethylsiloxane blocked with a silanol group (viscosity of 40 mPa.Math.s at 25 C.) was added, and the temperature raised to 190 C. 1.05 parts by mass of potassium dimethylsilanolate catalyst was added and allowed to react at 190 C. for 1 hour. The obtained reaction product was neutralized, then 0.02 parts by mass of polyether-modified silicone 501W and 1.83 parts by mass of ion exchanged water were added, to obtain a silicone-based anti-foaming agent oil compound. All steps were performed under a nitrogen gas purge. The obtained silicone-based anti-foaming agent oil compound had a viscosity of 15,000 mPa.Math.s.

Example 1

(21) After mixing 45 parts by mass of a polyorganosiloxane polymer crosslinked product having a polyoxyalkylene group manufactured in Production Examples 1 to 3 and Comparative Production Examples 1 and 2 and 25 parts by mass of an EOPOEO copolymer (ADEKA Pluronic (registered trademark) L-31), 30 parts by mass of the silicone-based anti-foaming agent oil compound #1 above was added and a homomixer was used to obtain a self-emulsifying anti-foaming agent composition. The diluted appearance of the resulting anti-foaming agent composition was a slightly bluish emulsion.

Examples 2 and 3 and Comparative Examples 1 and 2

(22) Anti-foaming agent compositions were prepared by the same procedure as in Example 1, except that the polyorganosiloxane polymer crosslinked product having a polyoxyalkylene group was changed as shown in Table 3. The diluted appearance of the resulting anti-foaming agent composition was a slightly bluish emulsion.

(23) TABLE-US-00003 TABLE 3 Anti-foaming agents of Examples 1 to 3 and Comparative Examples 1 and 2, and anti-foaming retention (unit of each component: g) Table 3-1 Example Example Example 1 2 3 Polyorganosiloxane polymer 45 crosslinked product of Production Example 1 Polyorganosiloxane polymer 45 crosslinked product of Production Example 2 Polyorganosiloxane polymer 45 crosslinked product of Production Example 3 Polyorganosiloxane polymer crosslinked product of Comparative Production Example 1 Polyorganosiloxane polymer crosslinked product of Comparative Production Example 2 Silicone-based anti-foaming agent 30 30 30 oil compound #1 EOPOEO copolymer (Adeka 25 25 25 Pluronic L-31) Anti-foaming retention 1 time Anti-foaming retention 2 times Anti-foaming retention 3 times Anti-foaming retention 4 times Table 3-2 Comparative Comparative Example 1 Example 2 Polyorganosiloxane polymer crosslinked product of Production Example 1 Polyorganosiloxane polymer crosslinked product of Production Example 2 Polyorganosiloxane polymer crosslinked product of Production Example 3 Polyorganosiloxane polymer 45 crosslinked product of Comparative Production Example 1 Polyorganosiloxane polymer 45 crosslinked product of Comparative Production Example 2 Silicone-based anti-foaming agent 30 30 oil compound #1 EOPOEO copolymer (Adeka 25 25 Pluronic L-31) Anti-foaming retention 1 time Anti-foaming retention 2 times Anti-foaming retention 3 times Anti-foaming retention 4 times X X

(24) As can be seen from Table 3 summarizing the results of each example and comparative example, when using the silicone anti-foaming agent composition containing the polyorganosiloxane polymer crosslinked product having a polyoxyalkylene group containing moiety structures (I) and (II) of the present invention, the anti-foaming speed is fast from the first time, and anti-foaming properties are superior. In addition, it was found practical anti-foaming properties could be obtained even after repeating the test four times. On the other hand, in the comparative examples having a low number of repetitions of siloxane units in moiety structure (I), it was found that a sufficient anti-foaming speed was not obtained, and that the anti-foaming properties were lowered for repeated tests. These results suggest that the polyorganosiloxane polymer crosslinked product having a polyoxyalkylene group shown in the examples improves the performance of the anti-foaming agent against dilution and shear forces, and is expected to improve anti-foaming retention.

(25) [Silicone-based anti-foaming agent oil compound #2]

(26) 59.1 parts by mass of polydimethylsiloxane blocked with a trimethylsilyl group (viscosity of 5,000 mPa.Math.s at 25 C.), 30.60 parts by mass of polydimethylsiloxane blocked with a silanol group (viscosity of 12,500 mPa.Math.s at 25 C.), and 3.06 parts by mass of polyethyl silicate (Cilbond 50 manufactured by Evonik) were placed in a three neck flask with a capacity of 1 L provided with a stirrer, a thermometer, a reflux condenser, and nitrogen gas supply, while stirring, and the temperature was raised to 110 C. A mixture of 1.54 parts by mass of premixed potassium dimethylsilanolate, 5.15 parts by mass of polydimethylsiloxane blocked with a trimethylsilyl group (viscosity of 5,000 mPa.Math.s at 25 C.), and 0.08 parts by mass of ethanol was added at 110 C. and stirring was continued for 30 minutes at 110 C. Next, silica (Aerosil 200, specific surface area: 200 m.sup.2/g, manufactured by Evonik) was added, and then homogeneously dispersed using a homomixer for 30 minutes while heating at 110 C. A mixture of 0.1 parts by mass of polyether-modified silicone 501W and 0.13 parts by mass of ion exchanged water was added. After stirring, 5.15 parts by mass of polydimethylsiloxane blocked with a silanol group (viscosity of 40 mPa.Math.s at 25 C.) was added, and the temperature raised to 190 C. 1.25 parts by mass of potassium dimethylsilanolate catalyst and allowed to react at 190 C. for 1 hour. The obtained reaction product was neutralized, then 0.02 parts by mass of polyether-modified silicone 501W and 2.19 parts by mass of ion exchanged water were added, to obtain a silicone-based anti-foaming agent oil compound. All steps were performed under a nitrogen gas purge. The obtained silicone-based anti-foaming agent oil compound had a viscosity of 33,500 mPa.Math.s.

Examples 4 to 6

(27) As shown in Table 4, anti-foaming agent compositions for Examples 4 to 6 were prepared by the same procedure as in Example 1, except that the silicone-based anti-foaming agent oil compound #2 above was used instead of the silicone-based anti-foaming agent oil compound #1. The evaluation results are shown in Table 4.

(28) TABLE-US-00004 TABLE 4 Anti-foaming agents of Examples 4 to 6, particle diameter and anti- foaming retention (unit of each component: g) Example Example Example 4 5 6 Silicone-based anti-foaming agent oil 30 30 30 compound #2 Polyorganosiloxane polymer crosslinked 45 product of Production Example 1 Polyorganosiloxane polymer crosslinked 45 product of Production Example 2 Polyorganosiloxane polymer crosslinked 45 product of Production Example 3 EOPOEO copolymer (Adeka Pluronic 25 25 25 L-31) Emulsion particle diameter after 1.5 1.2 1.0 emulsification (um) Anti-foaming retention 1 time Anti-foaming retention 2 times Anti-foaming retention 3 times Anti-foaming retention 4 times

(29) When the polyorganosiloxane polymer crosslinked product of the present invention is used together with the silicone-based anti-foaming agent oil compound #2, which is a trimethylsilyl group-terminated polydimethylsiloxane with a slightly longer chain length (viscosity of 5,000 mPa.Math.s at 25 C.), the anti-foaming retention is even more favorable, as shown in Table 4 (Examples 4 to 6), in addition to improved dilution stability against shear stress. Moreover, in the present invention, it is expected that more favorable anti-foaming properties can be achieved by using the anti-foaming agent oil compound according to the present invention in combination with a polyorganosiloxane polymer crosslinked product having a polyoxyalkylene group having an optimized structure.