Body type defoaming agent for water-based paint printing ink and preparation method of body type defoaming agent

Abstract

The invention relates to the technical field of defoaming agents, and discloses a bulk defoaming agent and a preparation method thereof.The bulk defoaming agent is synthesized from olefin and allyl polyether (unsaturated polyether) under the action of a cross-linking agent (isocyanate), the isocyanate can enable the olefin and the unsaturated polyether to react more completely in the reaction process, the cross-linking degree is improved, and the defoaming effect is improved. The molecular weight distribution of a reaction product is more uniform, so that a relatively good foam inhibition performance is achieved; the silicon polyether used at the same time and the finally added polyether (saturated polyether) can play a role in improving the compatibility in the reaction process; the bulk defoaming agent provided by the invention is used in the industries of water-based paint and ink, has relatively good compatibility and stability and excellent defoaming and foam-inhibiting performance, and particularly has outstanding foam-inhibiting performance in the field of water-based ink.

Description

Technical Field

[0001] The present invention relates to the technical field of defoamers, and specifically to a bulk defoamer applied to an aqueous coating and ink system and a preparation method thereof. Background Art

[0002] Defoamers are mainly divided into silicone defoamers and non-silicone defoamers. The defoamers applied in coatings are mainly two categories: modified silicone defoamers and mineral oil defoamers. As an earlier developed defoamer for coatings, the mineral oil defoamer has a series of disadvantages such as poor defoaming ability resulting in a high addition amount and the mineral oil affecting the glossiness, so the mineral oil defoamer is not suitable for use in coatings with high requirements for the paint film; the main component of the modified silicone defoamer is polyether-modified polysiloxane. Compared with the mineral oil defoamer, the defoaming ability is significantly improved, the addition amount is greatly reduced, and it will not affect the glossiness of the coating.

[0003] The patent with the publication number CN1041308879A introduces the compounding of a branched modified siloxane polymer modified with alkyl and polyether and a crosslinked modified siloxane polymer prepared from an unsaturated polyether, a divinyl-terminated polyorganosiloxane and a hydrogen-containing polyorganosiloxane, which has a good emulsifying and dispersing effect on the silicone composition with alkyl, but the compounding of these two polyether-modified polysiloxanes as a defoamer applied to the middle coating of coatings and inks has obvious defects. The patent with the publication number US6426379 introduces a defoamer prepared by compounding two different structures of silicopolyether and fumed silica. Although the addition of fumed silica ensures the defoaming and foam-suppressing performance, it will inevitably make the stability of the defoamer worse, and it is easy to cause defects in the coating, and has a high requirement for the leveling property of the silicopolyether.

[0004] In addition, the defoamers for aqueous coatings are divided into two types: bulk type and emulsion type. The patent with the publication number CN104722102A introduces a preparation method of a high-efficiency polyether silicone defoamer. A polyether silicone mother liquor is prepared by modifying hydrogen-containing silicone oil with an acrylate monomer or a double-bonded single-terminated polyurethane acrylate macromonomer and allyl polyether as a composite modifier, and then compounding with dimethyl silicone oil, hydroxyl silicone oil, fumed silica, non-ionic emulsifier and deionized water to play a defoaming role. The emulsion-type defoamer prepared by this method shows unstable phenomena due to the poor compatibility between the polyether-modified polysiloxane and the silicone oil. The patent with the publication number CN103657161A introduces an emulsion-type defoamer for coatings, but its defects are high emulsification process requirements, high addition amount and easy oil-water separation. The bulk defoamer can completely avoid these problems. Summary of the Invention

[0005] In view of the above problems that are prone to occur in the fields of waterborne coatings and inks, the present invention provides a bulk defoamer for use in the waterborne coating and ink industries, which has good compatibility and stability as well as excellent defoaming and foam suppression performance. Especially in the field of waterborne inks, the foam suppression performance is particularly prominent. The present invention utilizes the synthesis of olefins and allyl polyethers (unsaturated polyethers) under the action of a crosslinking agent (isocyanate). During the reaction process, the isocyanate can make the reaction between olefins and unsaturated polyethers more complete, improve the crosslinking degree, and make the molecular weight distribution of the reaction product more uniform, thereby achieving better foam suppression performance. At the same time, the silicone polyether and the finally added polyether (saturated polyether) used in the present invention can both play a role in improving compatibility during the reaction process.

[0006] The bulk defoamer for waterborne coatings and inks according to the present invention is composed of the following components:

[0007] A. Silicone polyether

[0008] The silicone polyether is prepared by the addition reaction of a hydrogen-containing polysiloxane and an unsaturated polyether under the action of a catalyst. The specific preparation method can be found in professional technical literature. The kinematic viscosity of the silicone polyether at 25°C is 10 - 50,000 mPa·s, preferably 50 - 20,000 mPa·s. The structural formula of the silicone polyether is represented by the following general formula:

[0009] (CH3)3SiO{(CH3)2SiO) x (CH3GSiO) y}(CH3)3①

[0010] Among them, G is a polyether group, which is represented by the following structural general formula:

[0011] -(CH2) z (EO) g (PO) h R ②

[0012] In the above structural formula, R is -H or -CH3 or -COCH3; the subscripts x, y, z, g, h are degrees of polymerization, x is an integer from 10 to 500; y is an integer from 1 to 50; z is an integer from 2 to 6; g is an integer from 1 to 40; h is an integer from 1 to 60. In structural formula ①, if G is different allyl alcohol polyether groups, then the silicone polyether is a silicone polyether synthesized from multiple polyethers. The dosage of the silicone polyether is 5 - 15% of the total mass of the bulk defoamer.

[0013] B. Olefin

[0014] The olefin is any one or a mixture of more than one of linear α-olefins, α-aromatic olefins or branched α-olefins, including α-octene, α-decene, α-dodecene, α-tetradecene, α-hexadecene, α-octadecene, α-eicosene, a mixture of linear α-olefins with C20-C24, a mixture of linear α-olefins with C24-C28, α-triacontene, α-methylstyrene, α-styrene, which can be used alone or in any proportion; the dosage of the α-olefin is 5-15% of the total mass of the bulk defoamer.

[0015] C. Allyl polyether

[0016] The structural general formula of allyl polyether is as follows:

[0017] CH2=CHCH2(OCH2CH2) b (OCH2CHCH3) c OH

[0018] Among them, b is an integer from 1 to 10, and c is an integer from 10 to 100. The dosage of the allyl polyether is 10-25% of the total mass of the bulk defoamer.

[0019] Among them, the mass ratio of α-olefin to allyl polyether is 1:1.2-1.6.

[0020] D. Crosslinking agent

[0021] The crosslinking agent is a polyisocyanate, specifically selected from any one of toluene diisocyanate, trimer of toluene diisocyanate, diphenylmethane-4,4,-diisocyanate, crude diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, trimer of hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, 1,12-dodecane diisocyanate, dimethylbiphenyl diisocyanate or 1,5-naphthalene diisocyanate; the dosage of the crosslinking agent is 0.1-5% of the total mass of the bulk defoamer.

[0022] E. Filler

[0023] The filler is silica, specifically selected from a mixture of fumed hydrophobic silica and precipitated hydrophobic silica with a specific surface area of 20-500 m 2 / g, where the ratio of fumed hydrophobic silica to precipitated hydrophobic silica is 2-5:1-3. The dosage of the filler is 3-8% of the total mass of the bulk defoamer.

[0024] F. Polyether

[0025] The polyether is a saturated polyether, and the structural general formula of the saturated polyether molecule is as follows:

[0026] [Y(EO) m(PO) n H] j R 3 i

[0027] In the molecular structural formula, the subscript: j is 1, 2 or 3, i is 0, 1 or 2, but j + i ≤ 3; Y is a linking group, a divalent group of -O- or -CO- or -NH-; R 3 is a substituent, an alkyl group with 1 to 30 carbon atoms; the subscripts m and n are degrees of polymerization, m is an integer from 1 to 100, and n is an integer from 0 to 80; the dosage of the polyether is 40 to 70% of the total mass of the bulk defoamer.

[0028] The preparation method of the bulk defoamer for waterborne coating inks is as follows:

[0029] 1) Add an olefin and an allyl polyether to a reaction vessel, start stirring and raise the temperature to 80 - 150 °C, add a crosslinking agent, stir evenly and keep warm for 1 - 2 h to fully react to obtain Reactant I;

[0030] 2) Slowly add a silicone polyether to Reactant I, stir and mix, and then continue to keep warm and react for 0.5 - 1 h to obtain Reactant II;

[0031] 3) Add fumed silica to Reactant II, stir for 0.5 - 1 h, cool to 60 - 70 °C after the fumed silica is fully dispersed and evenly distributed; add a polyether, continue to keep warm and stir at 60 - 70 °C for 0.5 - 1 h to obtain Reactant III;

[0032] 4) Pass Reactant III through a colloid mill for 3 - 5 min and cool to room temperature to obtain the bulk defoamer of the present invention. Detailed implementation mode

[0033] The following are the examples of the silicone polyether of the present invention:

[0034]

[0035] Example 1

[0036] 1) Add 15 parts of a mixture of α - dodecene and α - tetradecene in any proportion and 25 parts of allyl polyether CH2=CHCH2(OCH2CH2) 10 (OCH2CHCH3) 100 OH to a reaction vessel, start stirring and raise the temperature to 120 °C, add 0.1 part of hexamethylene diisocyanate, stir evenly and keep warm for 1 h to fully react to obtain Reactant I1;

[0037] 2) Slowly add 10 parts of silicone polyether A1 to Reactant I1, stir and mix, and then continue to keep warm and react for 0.5 h to obtain Reactant II1;

[0038] 3) Add 2 parts of fumed hydrophobic silica with a specific surface area of 300 m 2 / g and 1 part of precipitated hydrophobic silica with a specific surface area of 500 m 2 / g to Reactant II1, stir for 1 h, cool to 60 °C after the silica is fully and evenly dispersed; add 46.9 parts of polyether CH3CO(CH2) 16 (EO) 100 (PO) 80 H, and continue to keep warm and stir at 60 °C for 1 h to obtain Reactant III1;

[0039] 4) Pass Reactant III1 through a colloid mill for 3 min and cool to room temperature to obtain the bulk defoamer of the present invention.

[0040] Example 2

[0041] 1) Add 12.5 parts of α - styrene and 15 parts of allyl polyether CH2=CHCH2(OCH2CH2)(OCH2CHCH3) 10 OH to a reaction vessel, start stirring and raise the temperature to 150 °C, add 2 parts of 1,12 - dodecane diisocyanate, stir evenly and keep warm for 2 h to allow them to react fully to obtain Reactant I2;

[0042] 2) Slowly add 15 parts of silicone polyether A1 to Reactant I2, stir and mix, and then continue to keep warm and react for 1 h to obtain Reactant II2;

[0043] 3) Add 2 parts of fumed hydrophobic silica with a specific surface area of 20 m 2 / g and 2 parts of precipitated hydrophobic silica with a specific surface area of 80 m 2 / g to Reactant II2, stir for 1 h, cool to 65 °C after the silica is fully and evenly dispersed; add 51.5 parts of polyether CH3CO(CH2) 16 (EO) 100 (PO) 80 H, and continue to keep warm and stir at 65 °C for 1 h to obtain Reactant III2;

[0044] 4) Pass Reactant III2 through a colloid mill for 3 min and cool to room temperature to obtain the bulk defoamer of the present invention.

[0045] Example 3

[0046] 1) Add 6.25 parts of a mixture of α - dodecene and α - styrene in any proportion and 10 parts of allyl polyether CH2=CHCH2(OCH2CH2)4(OCH2CHCH3) 50OH is added to the reaction vessel, stirring is started and the temperature is raised to 130 °C. 1 part of dimethylbiphenyl diisocyanate is added. After stirring evenly, it is kept warm for 1 h to fully react to obtain reactant Ⅰ3;

[0047] 2) 6.75 parts of silicone polyether A2 are slowly added to reactant Ⅰ3. After stirring and mixing, the reaction is continued while keeping warm for 0.5 h to obtain reactant Ⅱ3;

[0048] 3) 4 parts of fumed hydrophobic silica with a specific surface area of 100 m 2 / g and 2 parts of precipitated hydrophobic silica with a specific surface area of 200 m 2 / g are added to reactant Ⅱ3. Stir for 1 h to fully disperse the silica evenly, and then cool down to 70 °C; 70 parts of polyether CH3(CH2) 16 (EO) 50 (PO) 26 H is added, and the stirring is continued while keeping warm at 70 °C for 1 h to obtain reactant Ⅲ3;

[0049] 4) Reactant Ⅲ3 is circulated through a colloid mill for 5 min and cooled to room temperature to obtain the bulk defoamer of the present invention.

[0050] Example 4

[0051] 1) 6.67 parts of α-methylstyrene and 10 parts of allyl polyether CH2=CHCH2(OCH2CH2)6(OCH2CHCH3) 60 OH are added to the reaction vessel. Stirring is started and the temperature is raised to 80 °C. 2.5 parts of toluene diisocyanate are added. After stirring evenly, it is kept warm for 1 h to fully react to obtain reactant Ⅰ4;

[0052] 2) 12 parts of silicone polyether A3 are slowly added to reactant Ⅰ4. After stirring and mixing, the reaction is continued while keeping warm for 0.5 h to obtain reactant Ⅱ4;

[0053] 3) 5 parts of fumed hydrophobic silica with a specific surface area of 150 m 2 / g and 3 parts of precipitated hydrophobic silica with a specific surface area of 300 m 2 / g are added to reactant Ⅱ4. Stir for 1 h to fully disperse the silica evenly, and then cool down to 70 °C; 60.83 parts of polyether CH3(CH2) 16 (EO) 50 (PO) 26 H is added, and the stirring is continued while keeping warm at 70 °C for 1 h to obtain reactant Ⅲ4;

[0054] 4) Reactant Ⅲ4 is circulated through a colloid mill for 5 min and cooled to room temperature to obtain the bulk defoamer of the present invention.

[0055] Example 5

[0056] 1) Add 10 parts of α-octene and 16 parts of allyl polyether CH2=CHCH2(OCH2CH2)3(OCH2CHCH3) 20 OH into the reaction vessel, start stirring and raise the temperature to 120 °C. Add 5 parts of hexamethylene diisocyanate trimer. After stirring evenly, keep the temperature for 1 h to make it react fully to obtain reactant I5;

[0057] 2) Slowly add 5 parts of silicone polyether A2 to reactant I5. After stirring and mixing, continue to keep the temperature for reaction for 0.5 h to obtain reactant II5;

[0058] 3) Add 3 parts of fumed hydrophobic silica with a specific surface area of 250 m 2 / g and 2 parts of precipitated hydrophobic silica with a specific surface area of 500 m 2 / g to reactant II5. Stir for 1 h to make the silica disperse evenly, and then cool down to 70 °C; add 59 parts of polyether CH3(CH2) 16 (EO) 50 (PO) 26 H, and continue to keep the temperature and stir for 1 h at 70 °C to obtain reactant III5;

[0059] 4) Pass reactant III5 through a colloid mill for 5 min and cool it to room temperature to obtain the bulk defoamer of the present invention.

[0060] Example 6

[0061] 1) Add 15 parts of a mixture of α-octene and α-eicosene in any proportion and 18 parts of allyl polyether CH2=CHCH2(OCH2CH2)5(OCH2CHCH3) 70 OH into the reaction vessel, start stirring and raise the temperature to 100 °C. Add 5 parts of diphenylmethane-4,4'-diisocyanate. After stirring evenly, keep the temperature for 2 h to make it react fully to obtain reactant I6;

[0062] 2) Slowly add 6 parts of silicone polyether A3 to reactant I6. After stirring and mixing, continue to keep the temperature for reaction for 0.5 h to obtain reactant II6;

[0063] 3) Add 4 parts of fumed hydrophobic silica with a specific surface area of 200 m 2 / g and 2 parts of precipitated hydrophobic silica with a specific surface area of 250 m 2 / g to reactant II6. Stir for 0.5 h to make the silica disperse evenly, and then cool down to 65 °C; add 50 parts of polyether CH3(CH2) 11 (EO) 15 (PO)2H, and continue to keep the temperature and stir for 0.5 h at 65 °C to obtain reactant III6;

[0064] 4) Pass the reactant Ⅲ6 through a colloid mill and circulate for 5 min, then cool to room temperature to obtain the bulk defoamer of the present invention.

[0065] Example 7

[0066] 1) Add 15 parts of α-octadecene and 19.5 parts of allyl polyether CH2=CHCH2(OCH2CH2) 10 (OCH2CHCH3) 10 OH into the reaction vessel, start stirring and raise the temperature to 110 °C, add 0.25 part of the trimer of toluene diisocyanate, stir evenly and keep warm for 2 h to make it react fully to obtain the reactant Ⅰ7;

[0067] 2) Slowly add 5 parts of silicone polyether A4 to the reactant Ⅰ7, stir and mix, and then continue to keep warm and react for 1 h to obtain the reactant Ⅱ7;

[0068] 3) Add 3 parts of fumed hydrophobic silica with a specific surface area of 400 m 2 / g and 3 parts of precipitated hydrophobic silica with a specific surface area of 500 m 2 / g to the reactant Ⅱ7, stir for 0.5 h, cool to 60 °C after the silica is fully dispersed and evenly mixed; add 54.25 parts of polyether CH3(CH2) 11 (EO) 15 (PO)2H, continue to keep warm and stir at 60 °C for 0.5 h to obtain the reactant Ⅲ7;

[0069] 4) Pass the reactant Ⅲ7 through a colloid mill and circulate for 5 min, then cool to room temperature to obtain the bulk defoamer of the present invention.

[0070] Example 8

[0071] 1) Add 14.3 parts of α-methylstyrene and 22.88 parts of allyl polyether CH2=CHCH2(OCH2CH2)8(OCH2CHCH3) 30 OH into the reaction vessel, start stirring and raise the temperature to 120 °C, add 4.82 parts of crude diphenylmethane diisocyanate, stir evenly and keep warm for 1.5 h to make it react fully to obtain the reactant Ⅰ8;

[0072] 2) Slowly add 15 parts of silicone polyether A3 to the reactant Ⅰ8, stir and mix, and then continue to keep warm and react for 1 h to obtain the reactant Ⅱ8;

[0073] 3) Add 2 parts of fumed hydrophobic silica with a specific surface area of 80 m 2 / g and 1 part of precipitated hydrophobic silica with a specific surface area of 150 m 2Precipitated hydrophobic silica at 40 parts per gram is stirred for 0.5 h. After the silica is fully and evenly dispersed, the temperature is lowered to 60 °C; 40 parts of polyether [(EO) 55 (PO) 10 H]2(CH2)5CH3 is added, and stirring is continued at 60 °C for 0.5 h to obtain Reactant III 8;

[0074] 4) Reactant III 8 is passed through a colloid mill for 4 min and cooled to room temperature to obtain the bulk defoamer of the present invention.

[0075] Example 9

[0076] 1) 10.67 parts of α-hexadecene and 16 parts of allyl polyether CH2=CHCH2(OCH2CH2)5(OCH2CHCH3) 55 OH are added to a reaction vessel. Stirring is started and the temperature is raised to 140 °C. 3.5 parts of dicyclohexylmethane diisocyanate are added. After stirring evenly, the mixture is kept warm for 1.5 h to allow full reaction to obtain Reactant I 9;

[0077] 2) 8.75 parts of silicone polyether A4 are slowly added to Reactant I 9. After stirring and mixing, the reaction is continued while keeping warm for 1 h to obtain Reactant II 9;

[0078] 3) 5 parts of fumed hydrophobic silica with a specific surface area of 350 m 2 / g and 2 parts of precipitated hydrophobic silica with a specific surface area of 420 m 2 / g are added to Reactant II 9. Stirring is carried out for 0.5 h. After the silica is fully and evenly dispersed, the temperature is lowered to 65 °C; 54.08 parts of polyether [(EO) 55 (PO) 10 H]2(CH2)5CH3 is added, and stirring is continued at 65 °C for 0.5 h to obtain Reactant III 9;

[0079] 4) Reactant III 9 is passed through a colloid mill for 4 min and cooled to room temperature to obtain the bulk defoamer of the present invention.

[0080] Example 10

[0081] 1) 8 parts of α-dodecene and 11.2 parts of allyl polyether CH2=CHCH2(OCH2CH2)7(OCH2CHCH3) 85 OH are added to a reaction vessel. Stirring is started and the temperature is raised to 150 °C. 4.5 parts of 1,5-naphthalene diisocyanate are added. After stirring evenly, the mixture is kept warm for 2 h to allow full reaction to obtain Reactant I 10;

[0082] 2) 10 parts of silicone polyether A4 are slowly added to Reactant I 10. After stirring and mixing, the reaction is continued while keeping warm for 1 h to obtain Reactant II 10;

[0083] 3) Add 2 parts of fumed hydrophobic silica with a specific surface area of 120 m 2 / g and 3 parts of precipitated hydrophobic silica with a specific surface area of 140 m 2 / g to Reactant II 10, stir for 0.5 h, cool to 65 °C after the silica is fully and evenly dispersed; add 61.3 parts of polyether [(EO) 35 (PO) 10 H]2(CH2)5CH3, and continue to stir and hold at 65 °C for 0.5 h to obtain Reactant III 10;

[0084] 4) Pass Reactant III 10 through a colloid mill and circulate for 3 min, and cool to room temperature to obtain the bulk defoamer of the present invention.

[0085] Comparative Example 1

[0086] 1) Add 15 parts of a mixture of α-dodecene and α-tetradecene in any proportion to a reaction vessel, raise the temperature to 120 °C, add 0.1 part of hexamethylene diisocyanate, stir evenly and hold for 1 h to allow full reaction to obtain Reactant I 11;

[0087] 2) Slowly add 10 parts of silicone polyether A1 to Reactant I 11, stir and mix, and continue to hold the reaction for 0.5 h to obtain Reactant II 11;

[0088] 3) Add 2 parts of fumed hydrophobic silica with a specific surface area of 300 m 2 / g and 1 part of precipitated hydrophobic silica with a specific surface area of 500 m 2 / g to Reactant II 11, stir for 1 h, cool to 60 °C after the silica is fully and evenly dispersed; add 71.9 parts of polyether CH3CO(CH2) 16 (EO) 100 (PO) 80 H, and continue to stir and hold at 60 °C for 1 h to obtain Reactant III 11;

[0089] 4) Pass Reactant III 11 through a colloid mill and circulate for 3 min, and cool to room temperature to obtain the bulk defoamer of the present invention.

[0090] Comparative Example 2

[0091] 1) Add 12.5 parts of α-styrene and 66.5 parts of allyl polyether CH2=CHCH2(OCH2CH2)(OCH2CHCH3) 10 OH to a reaction vessel, start stirring and raise the temperature to 150 °C, add 2 parts of 1,12-dodecane diisocyanate, stir evenly and hold for 2 h to allow full reaction to obtain Reactant I 12;

[0092] 2) Slowly add 15 parts of silicone polyether A1 to reactant I 12. After stirring and mixing, continue to keep the temperature for reaction for 1 h to obtain reactant II 12;

[0093] 3) Add 2 parts of fumed hydrophobic silica with a specific surface area of 20 m 2 / g and 2 parts of precipitated hydrophobic silica with a specific surface area of 80 m 2 / g to reactant II 12, stir for 1 h. After the silica is fully dispersed and homogenized, cool down to 65 °C and keep stirring for 1 h to obtain reactant III 12;

[0094] 4) Pass reactant III 12 through a colloid mill and circulate for 3 min, and cool to room temperature to obtain the bulk defoamer of the present invention.

[0095] Comparative Example 3

[0096] 1) Add 6.25 parts of a mixture of α-dodecene and α-styrene in any proportion and 10 parts of allyl polyether CH2=CHCH2(OCH2CH2)4(OCH2CHCH3) 50 OH to a reaction vessel, start stirring and raise the temperature to 130 °C, add 1 part of propyl methacrylate, stir evenly and keep the temperature for 1 h to make it react fully to obtain reactant I 13;

[0097] 2) Slowly add 6.75 parts of silicone polyether A2 to reactant I 13. After stirring and mixing, continue to keep the temperature for reaction for 0.5 h to obtain reactant II 13;

[0098] 3) Add 4 parts of fumed hydrophobic silica with a specific surface area of 100 m 2 / g and 2 parts of precipitated hydrophobic silica with a specific surface area of 200 m 2 / g to reactant II 13, stir for 1 h. After the silica is fully dispersed and homogenized, cool down to 70 °C; add 70 parts of polyether CH3(CH2) 16 (EO) 50 (PO) 26 H, and continue to keep the temperature and stir for 1 h at 70 °C to obtain reactant III 13;

[0099] 4) Pass reactant III 13 through a colloid mill and circulate for 5 min, and cool to room temperature to obtain the bulk defoamer of the present invention.

[0100] Comparative Example 4

[0101] 1) Add 6.67 parts of α-methylstyrene and 10 parts of allyl polyether CH2=CHCH2(OCH2CH2)6(OCH2CHCH3) 60OH is added into the reaction vessel, stirring is started and the temperature is raised to 80 °C. 2.5 parts of toluene diisocyanate are added. After stirring evenly, it is kept warm for 1 h to fully react to obtain reactant I 14;

[0102] 2) 12 parts of silicone polyether A3 are slowly added to reactant I 14. After stirring and mixing, the reaction is continued while keeping warm for 0.5 h to obtain reactant II 14;

[0103] 3) 8 parts of fumed hydrophobic silica with a specific surface area of 150 m 2 / g is added to reactant II 14, and it is stirred for 1 h. After the silica is fully dispersed and homogenized, the temperature is lowered to 70 °C; 60.83 parts of polyether CH3(CH2) 16 (EO) 50 (PO) 26 H is added, and the stirring is continued while keeping warm at 70 °C for 1 h to obtain reactant III 14;

[0104] 4) Reactant III 14 is passed through a colloid mill and circulated for 5 min, and then cooled to room temperature to obtain the bulk defoamer of the present invention.

[0105] Comparative Example 5

[0106] 1) 27.31 parts of α-octene and 7.69 parts of allyl polyether CH2=CHCH2(OCH2CH2)3(OCH2CHCH3) 20 OH are added into the reaction vessel, stirring is started and the temperature is raised to 120 °C. 5 parts of hexamethylene diisocyanate trimer are added. After stirring evenly, it is kept warm for 1 h to fully react to obtain reactant I 15;

[0107] 2) 5 parts of silicone polyether A2 are slowly added to reactant I 15. After stirring and mixing, the reaction is continued while keeping warm for 0.5 h to obtain reactant II 15;

[0108] 3) 3 parts of fumed hydrophobic silica with a specific surface area of 250 m 2 / g and 2 parts of precipitated hydrophobic silica with a specific surface area of 500 m 2 / g are added to reactant II 15, and it is stirred for 1 h. After the silica is fully dispersed and homogenized, the temperature is lowered to 70 °C; 50 parts of polyether CH3(CH2) 16 (EO) 50 (PO) 26 H is added, and the stirring is continued while keeping warm at 70 °C for 1 h to obtain reactant III 15;

[0109] 4) Reactant III 15 is passed through a colloid mill and circulated for 5 min, and then cooled to room temperature to obtain the bulk defoamer of the present invention.

[0110] Comparative Example 6

[0111] 1) Add 15 parts of a mixture of α-octene and α-eicosene in any proportion, 18 parts of allyl polyether CH2=CHCH2(OCH2CH2)5(OCH2CHCH3) 70 OH, 5 parts of diphenylmethane-4,4'-diisocyanate, 6 parts of silicone polyether A3, 4 parts of fumed hydrophobic silica with a specific surface area of 200 m 2 / g, and 2 parts of precipitated hydrophobic silica with a specific surface area of 250 m 2 / g, 50 parts of polyether CH3(CH2) 11 (EO) 15 (PO)2H into a reaction vessel, start stirring and raise the temperature to 100 °C. After stirring evenly, keep the temperature for 2 h to allow full reaction to obtain reactant I 16;

[0112] 2) Pass reactant I 16 through a colloid mill for 5 min and cool to room temperature to obtain the bulk defoamer of the present invention.

[0113] Performance Test

[0114] (1) Compatibility Test

[0115] Test method: Add 200 g of self-prepared waterborne coating into a 1000 ml stainless steel cup, then add 0.3% defoamer. Use a laboratory high-speed disperser to disperse at a speed of 1000 rpm for 10 min. Take a little and let it stand on a glass plate. Use a 75 um wet film applicator to scrape the coating evenly. Observe the state of the coating film and represent it with a grade. The higher the grade, the better the compatibility.

[0116] Coating Grade Classification:

[0117]

[0118] Compatibility Test Results:

[0119]

[0120] (2) Centrifugal Stability Test

[0121] Test method: Put the foam control agent into a graduated centrifuge tube and centrifuge at a high speed of 3000 rpm for 15 min. After centrifugation, observe whether the emulsion in the centrifuge tube is stratified;

[0122]

[0123] (3) High Temperature Stability

[0124] The stability of the sample was tested using a Formulaction / Turbiscan Tower / multiple light scattering stability analyzer at a test temperature of 40 °C and a sample amount of 20 g. The smaller the TSI index in the test results, the better the stability of the sample.

[0125]

[0126] (4)Defoaming performance test

[0127] In a 500 ml graduated cylinder, 110 g of the ink sample was put in, and an appropriate amount of water was added to adjust the viscosity. 0.3% defoamer was added, and the air drum device was put in. The flow rate was adjusted to an appropriate value, and then air was continuously blown into the graduated cylinder through the air drum. The change law of the foam volume V with time t was recorded; with the air drum time fixed, the foam heights were compared.

[0128]

Claims

1. An aqueous coating ink bulk defoamer, characterized in that, It consists of the following components: A. Silicone polyether The silicone polyether is prepared by the addition reaction of hydrogen-containing polysiloxane and unsaturated polyether under the action of a catalyst. The specific preparation method can be found in professional technical literature. The dosage of the silicone polyether is 5-15% of the total mass of the bulk defoamer. B. Olefin The olefin is any one or a mixture of linear α-olefins, α-aromatic olefins or branched α-olefins, and the dosage is 5-15% of the total mass of the bulk defoamer. C. Allyl polyether The dosage of the allyl polyether is 10-25% of the total mass of the bulk defoamer. D. Crosslinking agent The crosslinking agent is polyisocyanate, and the dosage is 0.1-5% of the total mass of the bulk defoamer. E. Filler The filler is silica, and the dosage is 3-8% of the total mass of the bulk defoamer. F. Polyether The polyether is saturated polyether, and the dosage is 40-70% of the total mass of the bulk defoamer. A bulk defoamer for waterborne coating ink, and its preparation method is as follows: 1) Add the olefin and allyl polyether into a reaction vessel, start stirring and raise the temperature to 80-150 °C, add the crosslinking agent, stir evenly and keep warm for 1-2 h to fully react to obtain reactant I. 2) Slowly add the silicone polyether to reactant I, stir and mix, and continue to keep warm and react for 0.5-1 h to obtain reactant II. 3) Add silica to reactant II, stir for 0.5-1 h to fully disperse the silica evenly, and then cool to 60-70 °C; add polyether, and continue to keep warm and stir at 60-70 °C for 0.5-1 h to obtain reactant III. 4) Pass reactant III through a colloid mill and circulate for 3-5 min, and cool to room temperature to obtain the bulk defoamer of the present invention.

2. The bulk defoamer for waterborne coating ink according to claim 1, characterized in that, The structural formula of the silicone polyether is represented by the following general formula: (CH3)3SiO{(CH3)2SiO) x (CH3GSiO) y}(CH3)3 ① Among them, G is a polyether group, which is represented by the following structural general formula: -(CH2) z (EO) g (PO) h R ② In the above structural formula, R is -H or -CH3 or -COCH3; the subscripts x, y, z, g, h are degrees of polymerization, x is an integer of 10-500; y is an integer of 1-50; z is an integer of 2-6; g is an integer of 1-40; h is an integer of 1-60; in structural formula ①, if G is different allyl alcohol polyether groups, then the silicone polyether is a silicone polyether synthesized from multiple polyethers.

3. An antifoaming agent for aqueous coating ink according to claim 1, characterized in that, The kinematic viscosity of the silicone polyether at 25 °C is 10-50,000 mPa·s.

4. An organic defoamer for waterborne coating inks according to claim 1, characterized in that, The olefin specifically includes α-octene, α-decene, α-dodecene, α-tetradecene, α-hexadecene, α-octadecene, α-eicosene, a mixture of linear α-olefins of C20-C24, a mixture of linear α-olefins of C24-C28, α-triacontene, α-methylstyrene, α-styrene, which can be used alone or in any proportion.

5. An antifoaming agent for water-based coating ink according to claim 1, characterized in that, The crosslinking agent is specifically selected from any one of toluene diisocyanate, trimer of toluene diisocyanate, diphenylmethane-4,4'-diisocyanate, crude diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, trimer of hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, 1,12-dodecane diisocyanate, dimethylbiphenyl diisocyanate or 1,5-naphthalene diisocyanate.

6. The bulk defoamer for waterborne coating ink according to claim 1, wherein, The filler is specifically selected from a mixture of fumed hydrophobic silica and precipitated hydrophobic silica with a specific surface area of 20 to 500 m 2 / g, wherein the ratio of fumed hydrophobic silica to precipitated hydrophobic silica is 2 to 5:1 to 3.

7. An antifoaming agent of bulk type for waterborne coating ink according to claim 1, characterized in that, The general structural formula of the saturated polyether molecule is as follows: [Y(EO) m (PO) n H] j R 3 i In the molecular structural formula, the subscript: j is 1, 2 or 3, i is 0, 1 or 2, but j + i ≤ 3; Y is a linking group, a divalent group of -O- or -CO- or -NH-; R 3 is a substituent, an alkyl group with 1 to 30 carbon atoms; the subscripts m and n are degrees of polymerization, m is an integer from 1 to 100, and n is an integer from 0 to 80.

8. The bulk defoamer for water-based coating ink according to claim 1, characterized in that, The mass ratio of the α-olefin to the allyl polyether is 1:1.2 to 1.6.

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