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CN-121975484-A - Deacetic acid type mildew-proof silicone sealant and preparation method thereof

CN121975484ACN 121975484 ACN121975484 ACN 121975484ACN-121975484-A

Abstract

The invention discloses a deacetylated mildew-proof silicone sealant and a preparation method thereof, and relates to the technical field of silicone sealant. The mildew-proof silicone sealant comprises the raw materials of hydroxyl-terminated polydimethylsiloxane, fumed silica, dimethyl silicone oil, methyl silicone resin coated octyl isothiazolinone microcapsule, a cross-linking agent, a catalyst, a silane coupling agent, an antioxidant, iodopropynyl butyl carbamate and amino modified silicon dioxide. The preparation method of the mildew-proof silicone sealant comprises the steps of preparing methyl silicone resin coated octyl isothiazolinone microcapsules, preparing base adhesive and preparing the mildew-proof silicone sealant. The mildew-proof silicone sealant prepared by the invention has good long-acting mildew-proof effect and excellent mildew-proof stability.

Inventors

  • GAO JINXU
  • CHI XIANG
  • LIU SHULIANG

Assignees

  • 潍坊工程职业学院

Dates

Publication Date
20260505
Application Date
20260319

Claims (10)

  1. 1. The preparation method of the deacetyl mould-proof silicone sealant is characterized by comprising the steps of preparing methyl silicone resin coated octyl isothiazolinone microcapsules, preparing base adhesive and preparing the mould-proof silicone sealant; The preparation method comprises the following steps of adopting hydroxyl-terminated polydimethylsiloxane, fumed silica, simethicone, methyl silicone resin coated octyl isothiazolinone microcapsule, a cross-linking agent, a catalyst, a silane coupling agent, an antioxidant, iodopropynyl butyl carbamate and amino modified silicon dioxide, wherein the cross-linking agent is methyltriacetoxy silane; Mixing methyltrimethoxysilane and absolute ethyl alcohol, putting the mixture into an ice-water bath, dropwise adding an ammonia water solution, and reacting for 1-2 hours to obtain methyltrimethoxysilane prehydrolysis liquid; Dissolving an emulsifier in deionized water, adding octyl isothiazolinone, stirring to obtain octyl isothiazolinone emulsion, regulating the pH value of the emulsion, dripping methyl trimethoxy silane pre-hydrolysate, heating to 40-50 ℃, reacting for 12-16h, cooling to room temperature after the reaction is finished, filtering to collect solid, washing and drying to obtain the methyl silicone resin coated octyl isothiazolinone microcapsule, wherein the emulsifier is sodium dodecyl benzene sulfonate.
  2. 2. The preparation method of the deacetyl mould-proof silicone sealant is characterized by comprising, by weight, 80-90 parts of hydroxyl-terminated polydimethylsiloxane, 10-20 parts of fumed silica, 10-15 parts of simethicone, 1.5-2 parts of methyl silicone resin coated octyl isothiazolinone microcapsule, 5-10 parts of cross-linking agent, 0.2-0.5 part of catalyst, 1-2 parts of silane coupling agent, 0.3-0.5 part of antioxidant, 0.2-0.4 part of iodopropynyl butyl carbamate and 0.3-0.5 part of amino modified silicon dioxide.
  3. 3. The preparation method of the deacetyl mould-proof silicone sealant according to claim 1 is characterized in that the mass ratio of the methyltrimethoxysilane to the absolute ethyl alcohol is 1 (1-2), and the mass ratio of the ammonia water solution to the methyltrimethoxysilane is 0.25-3:1.
  4. 4. The method for preparing the deacetyl mould-proof silicone sealant according to claim 1, wherein the mass ratio of the emulsifier to deionized water is (0.2-0.5) 100.
  5. 5. The preparation method of the deacetyl mould-proof silicone sealant according to claim 1 is characterized in that the mass ratio of the octyl isothiazolinone to the emulsifier is 20 (1-2).
  6. 6. The method for preparing the deacetyl type mildew-proof silicone sealant according to claim 1, wherein the step of adjusting the pH value of the emulsion is characterized in that ammonia water is added to adjust the pH value of the emulsion to 9-10.
  7. 7. The preparation method of the deacetyl mould-proof silicone sealant according to claim 1 is characterized in that the mass ratio of the methyltrimethoxysilane prehydrolysis liquid to the octyl isothiazolinone emulsion is 1 (1.8-2).
  8. 8. The method for preparing the deacetyl type mildew-proof silicone sealant according to claim 1, wherein the washing is carried out by alternately washing the solid with deionized water and ethanol for 3-5 times.
  9. 9. The preparation method of the deacetyl mould-proof silicone sealant is characterized in that the base sealant is prepared by adding hydroxyl-terminated polydimethylsiloxane into a stirrer, adding fumed silica and simethicone, heating, opening vacuum, stirring, maintaining vacuum, cooling, adding an antioxidant, amino modified silicon dioxide, methyl silicone resin coated octyl isothiazolinone microcapsule and iodopropynyl butyl carbamate, and stirring to obtain the base sealant.
  10. 10. The preparation method of the deacetyl type mildew-proof silicone sealant is characterized in that nitrogen is introduced into a stirrer for protection, the rotating speed is set to be 80-120rpm, a cross-linking agent is added into a basic colloid, a catalyst is added into the basic colloid, a silane coupling agent is added into the basic colloid, stirring is carried out, and the mildew-proof silicone sealant is obtained after defoaming.

Description

Deacetic acid type mildew-proof silicone sealant and preparation method thereof Technical Field The invention relates to the technical field of silicone adhesives, in particular to a deacetylated mildew-proof silicone sealant and a preparation method thereof. Background The deacetylated silicone sealant has excellent adhesive property, weather resistance and construction convenience, is widely applied to the fields of building door and window joints, kitchen and bathroom decoration, household appliance sealing and the like, and particularly in a humid and dark use environment, the mildew-proof performance of the deacetylated silicone sealant directly determines the service life and the use experience of a product, so that the deacetylated silicone sealant becomes one of core indexes for measuring the quality of the sealant. At present, the mildew-proof function is usually realized in the industry by adding an organic mildew-proof agent (such as isothiazolinone and benzimidazole) or an inorganic mildew-proof agent (such as nano silver and zinc oxide) into a sealant matrix, but the prior art has obvious defects that the mildew-proof effect is easy to decay rapidly along with time due to migration and volatilization, and the inorganic mildew-proof agent is easy to have uneven dispersion in a silicone sealant system, so that the mildew-proof effect is unstable. The prior art with publication number CN117089317A discloses a long-acting antibacterial mildew-proof silicone adhesive and a preparation method thereof, the prior art adopts beta-cyclodextrin to include the mildew-proof agent, the bonding force with a silicone crosslinked network is weak, acetic acid can accelerate the degradation of the mildew-proof agent, and the long-term stability is insufficient. The prior art with publication number CN119875573A discloses a transparent deacidification type long-acting mildew-proof silicone sealant, and the prior art is directly added with a mildew preventive, has limited long-acting mildew-proof effect, is easy to migrate and run off in long-term use, and cannot meet long-acting requirements. In summary, the prior art scheme improves certain properties of the mildew-proof silicone sealant to a certain extent, but still has the technical problems of limited long-acting mildew-proof effect and insufficient mildew-proof stability. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a deacetyl type mildew-proof silicone sealant and a preparation method thereof, and the aim of the invention is achieved that the mildew-proof silicone sealant with good long-acting mildew-proof effect and excellent mildew-proof stability is prepared. In order to achieve the above purpose, the following technical scheme is adopted: The acetic acid-removing type mildew-proof silicone sealant comprises, by weight, 80-90 parts of hydroxyl-terminated polydimethylsiloxane, 10-20 parts of fumed silica, 10-15 parts of simethicone, 1.5-2 parts of methyl silicone resin coated octyl isothiazolinone microcapsule, 5-10 parts of cross-linking agent, 0.2-0.5 part of catalyst, 1-2 parts of silane coupling agent, 0.3-0.5 part of antioxidant, 0.2-0.4 part of iodopropynyl butyl carbamate and 0.3-0.5 part of amino modified silicon dioxide. The cross-linking agent is methyl triacetoxy silane. The catalyst is dibutyl tin dilaurate. The amino modified silicon dioxide is silane coupling agent KH550 modified silicon dioxide. The invention also provides a preparation method of the acetic acid-removing type mildew-proof silicone sealant, which comprises the steps of preparing methyl silicone resin coated octyl isothiazolinone microcapsules, preparing base adhesive and preparing the mildew-proof silicone sealant; Mixing methyltrimethoxysilane and absolute ethyl alcohol, putting the mixture into an ice-water bath, dropwise adding an ammonia water solution, and reacting to obtain methyltrimethoxysilane prehydrolysis liquid; Dissolving an emulsifier in deionized water, adding octyl isothiazolinone, stirring to obtain octyl isothiazolinone emulsion, regulating the pH value of the emulsion, dripping methyl trimethoxy silane pre-hydrolysate, heating to react, cooling to room temperature after the reaction is finished, carrying out suction filtration, and washing and drying to obtain the methyl silicone resin coated octyl isothiazolinone microcapsule, wherein the emulsifier is sodium dodecyl benzene sulfonate. Further, the mass ratio of the methyltrimethoxysilane to the absolute ethyl alcohol is 1 (1-2), and the mass ratio of the ammonia water solution to the methyltrimethoxysilane is 0.25-3:1. Further, the mass ratio of the emulsifier to the deionized water is (0.2-0.5) 100, the mass ratio of the octyl isothiazolinone to the emulsifier is (1-2), and the mass ratio of the methyltrimethoxysilane prehydrolysis liquid to the octyl isothiazolinone emulsion is (1.8-2). Further, the methyltrimethoxysilane and absolute ethyl alcohol are