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CN-122011399-A - Silicone oil modified polyether defoamer and preparation method and application thereof

CN122011399ACN 122011399 ACN122011399 ACN 122011399ACN-122011399-A

Abstract

The application discloses a preparation method of a silicone oil modified polyether defoamer, which comprises the step of generating addition reaction between alkynol (EO/PO) block polyether and allyl alcohol (PO/EO) block polyether under the action of a catalyst to generate the silicone oil modified polyether defoamer. The silicone oil modified polyether defoamer has the characteristics of high foam breaking speed and long foam inhibiting period, and has excellent high temperature resistance, chemical stability and excellent compatibility.

Inventors

  • Ren Sicheng
  • LI ZHIJIAO

Assignees

  • 广东良仕工业材料有限公司

Dates

Publication Date
20260512
Application Date
20260313

Claims (10)

  1. 1. A preparation method of a silicone oil modified polyether defoamer is characterized in that alkynol (EO/PO type) block polyether and allyl alcohol (PO/EO type) block polyether undergo an addition reaction under the action of a catalyst to generate the silicone oil modified polyether defoamer.
  2. 2. The preparation method of the silicone oil modified polyether defoamer according to claim 1, which is characterized by comprising the following steps: s1, performing [2+2] cycloaddition reaction on alkynol (EO/PO type) block polyether and allyl alcohol (PO/EO type) block polyether under the action of a first catalyst or a photoinitiator to generate branched polyether containing a quaternary cyclobutene structure; s2, hydrosilylation is carried out on the branched polyether generated in the step S1 and hydrogen-containing silicone oil under the action of a second catalyst, so that the silicone oil modified polyether defoamer is generated.
  3. 3. The preparation method of the silicone oil modified polyether defoamer according to claim 2, wherein step S1 is specifically that after alkynol (EO/PO type) block polyether and allyl alcohol (PO/EO type) block polyether are mixed, the first catalyst or photoinitiator is added, and the mixture is reacted for 4 to 8 hours under the irradiation of ultraviolet light at the temperature of 80 to 90 ℃ in a nitrogen atmosphere, so as to generate branched polyether containing a quaternary cyclobutene structure.
  4. 4. The method for producing a silicone oil-modified polyether defoamer according to claim 2, wherein in step S1, the ratio of the amounts of the materials of the alkynol (EO/PO type) block polyether and the allyl alcohol (PO/EO type) block polyether is 1 (1-1.5).
  5. 5. The preparation method of the silicone oil modified polyether defoamer according to claim 2, wherein in the step S1, the first catalyst is a transition metal catalyst, and the dosage of the first catalyst is 50-1000ppm; And/or the photoinitiator is selected from benzophenone, methyl benzoyl formate or 4-phenylbenzophenone, and the mass of the photoinitiator added accounts for 0.5% -1.0% of the mass of all added substances in the step S1.
  6. 6. The preparation method of the silicone oil modified polyether defoamer according to claim 2, wherein in the step S2, specifically, after the branched polyether generated in the step S1 and hydrogen-containing silicone oil are mixed, the second catalyst is added, and the silicone oil modified polyether defoamer is generated through hydrosilylation reaction under the nitrogen atmosphere and at the temperature of 80-100 ℃ for 3-5 hours.
  7. 7. The method for producing a silicone oil-modified polyether defoamer according to claim 6, wherein in step S2, the ratio of the amounts of branched polyether and hydrogen-containing silicone oil produced in step S1 is (1-6): 1; The hydrogen-containing silicone oil is side hydrogen-containing silicone oil.
  8. 8. The method for preparing a silicone oil modified polyether defoamer of claim 6, wherein in step S2, said second catalyst is selected from a Speier catalyst, a Karstedt catalyst, a platinum-phosphine complex, a Wilkinson catalyst, a ruthenium catalyst, an iridium catalyst, a cobalt catalyst, and a nickel catalyst; The second catalyst is used in an amount of 3 to 50ppm.
  9. 9. A silicone oil-modified polyether defoamer, characterized by being produced by the production method of the silicone oil-modified polyether defoamer as claimed in any one of claims 1 to 8.
  10. 10. Use of the silicone oil-modified polyether defoamer produced by the production method of the silicone oil-modified polyether defoamer according to any one of claims 1 to 8 or the silicone oil-modified polyether defoamer according to claim 9 in a foam suppression and defoaming treatment for papermaking.

Description

Silicone oil modified polyether defoamer and preparation method and application thereof Technical Field The application relates to the technical field of papermaking chemicals, in particular to a silicone oil modified polyether defoamer and a preparation method and application thereof. Background In the paper industry, foam formation and accumulation are common problems throughout the entire process of pulping, papermaking, and coating, and have significant adverse effects on both production efficiency and final paper quality. In the pulping process, natural components such as fatty acid and resin acid contained in the raw materials react with chemicals such as caustic soda and sodium sulfide to produce substances having foaming properties such as fatty acid soap and resin acid soap. Meanwhile, high molecular compounds such as cellulose play a role in stabilizing foam, and a large amount of stable foam is formed due to air entrainment in the slurry conveying and mixing processes. The foam not only disturbs the subsequent washing, conveying and bleaching operations, causes the problems of floating pulp and the like, affects the quality of paper pulp, but also can enrich foaming and foam stabilizing components in the washing black liquor. If the black liquor is not effectively defoamed, the operation of the subsequent process is hindered and the alkali recovery efficiency is reduced. In the papermaking process, foam is easily generated under the condition that air is introduced into the slurry through mechanical operation by residual foaming and foam stabilizing substances in the slurry. The foam will cause the uniformity of sizing to decrease, the paper banner quantitative distribution to be uneven, and may cause the defects of spots, light transmission points or holes on the paper surface, even cause paper breakage accidents in severe cases, directly affect the product quality and the production continuity. In the coating process, due to the existence of easily foaming components such as pigment, alkaline substances and the like, the three-phase foam formed by liquid film, solid particles and gas is easily formed by adding air by mechanical stirring. The foam can cause appearance defects such as white spots on the coating surface, and the like, and influence the visual effect and printing applicability of the paper. In the prior art, although the organic silicon defoamer is widely applied in a plurality of industrial fields, a plurality of defects still exist in the actual use process, the applicability and the effect stability of the organic silicon defoamer in different systems are restricted, and the organic silicon defoamer is specifically expressed as follows: (1) The silicone defoamer has the problem of difficult dispersion in an aqueous phase system, and because polysiloxane is difficult to dissolve in water, auxiliary emulsification is usually carried out by a dispersing agent to realize uniform dispersion in a water system. However, too high a dispersant amount can result in an emulsion system that is too stable, but rather weakens the penetration and foam breaking capabilities of the defoamer, so that the amount of dispersant added needs to be strictly controlled, and the complexity of process operation is increased. (2) The application effect of the defoamer in an oily system is also not ideal, and the defoamer has certain oil solubility and is easy to dissolve or migrate into an oil phase in the oil system, so that the enrichment capacity of the defoamer at a bubble interface is reduced, and the defoaming efficiency of the defoamer in an actual oil system is affected. (3) The stability under high temperature or strong alkali condition is still insufficient, the organic silicon defoamer is easy to degrade or lose efficacy in high temperature environment for a long time, and phenomena such as demulsification, layering and the like can occur in strong alkaline medium, so that the defoaming performance is reduced, and the pH value and the temperature range of the use environment are limited. (4) The organic silicon defoamer has poor compatibility in polar solvents, is difficult to realize uniform dispersion in a solvent system with stronger polarity due to the molecular structure characteristic, and easily causes the problem of inconsistent defoaming effect due to overhigh or overlow local concentration. (5) Such defoamers may have drawbacks in applications such as high gloss coatings, optical coatings, and the like, which are critical to apparent quality. Residual silicone components may cause oil spotting, hazing or uneven gloss on the finished product surface, which may adversely affect the visual and performance properties of the final product. In view of the above technical problems, those skilled in the art are devoted to researching a silicone oil modified polyether defoamer which solves the above problems and simultaneously gives consideration to environmental protection, high efficiency and