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CN-121975389-A - High-flexibility polyester fluoropropene dispersoid and preparation method thereof

CN121975389ACN 121975389 ACN121975389 ACN 121975389ACN-121975389-A

Abstract

The application relates to the technical field of high polymer materials, in particular to a high-flexibility polyester fluoropropene dispersoid and a preparation method thereof, wherein the dispersion comprises the steps of taking linear saturated polyester diol, adding an activating agent to carry out end group activation treatment on a polyester main chain, and then adding a catalyst to carry out grafting treatment to obtain bridged polyester; introducing fluoropropene gas into the reaction kettle of the bridged polyester for copolymerization treatment to obtain a copolymer, cooling the copolymer to a preset value, adding a surfactant to coat the copolymer, slowly adding deionized water to perform shearing treatment to obtain an aqueous dispersion, adding tetraethoxysilane into the aqueous dispersion, and performing hydrolysis treatment under the condition of pH 4.3-4.6 to obtain the high-flexibility polyester fluoropropene dispersion. According to the application, the breaking elongation, bending tolerance and cracking resistance of the dispersion after film formation are improved, and the hidden trouble of material failure in high-flexibility scenes such as flexible electronic base materials, bendable coatings and the like is solved.

Inventors

  • TAN MEIRONG
  • ZHANG YANG

Assignees

  • 深圳市深赛尔股份有限公司

Dates

Publication Date
20260505
Application Date
20260202

Claims (10)

  1. 1. A process for preparing a highly flexible polyester fluoropropene dispersion comprising: Taking linear saturated polyester diol, adding an activating agent to activate the end group of the polyester main chain, and adding a catalyst to graft to obtain bridged polyester; introducing fluoropropene gas into the reaction kettle of the bridged polyester for copolymerization treatment to obtain a copolymer; Cooling the copolymer to a preset value, adding a surfactant to coat the copolymer, and slowly adding deionized water to perform shearing treatment to obtain an aqueous dispersion; And adding tetraethoxysilane into the water dispersion, and performing hydrolysis treatment under the condition of pH 4.3-4.6 to obtain the high-flexibility polyester fluoropropene dispersion.
  2. 2. The method of preparing a highly flexible polyester fluoropropene dispersion according to claim 1 wherein said activating agent is any one of diphenyl phosphate, xylene phosphate or triphenyl phosphate.
  3. 3. The method of preparing a highly flexible polyester fluoropropene dispersion according to claim 1 wherein said catalyst is any one of diphenyl phosphine, triphenylphosphine or tributylphosphine.
  4. 4. The process for preparing a highly flexible polyester fluoropropene dispersion according to claim 1, wherein said step of subjecting the polyester main chain to end-group activation treatment by adding an activator to a linear saturated polyester diol comprises: Pre-dehydrating the linear saturated polyester diol for 1-2 hours under the conditions of vacuum degree of-0.08 to-0.10 MPa and temperature of 100-110 ℃ to obtain dehydrated polyester diol; Under the protection of nitrogen, adding an activator containing phenyl phosphate groups into the dehydrated polyester diol step by step, stirring uniformly, and heating to 110-120 ℃ for reaction to obtain double-active-end polyester; and cooling the double-active-end polyester to 60-65 ℃ and then filtering to obtain an activated polyester solution.
  5. 5. The process for preparing a highly flexible polyester fluoropropene dispersion according to claim 1, wherein said step of adding a catalyst for grafting treatment to obtain a bridged polyester comprises: Under the protection of nitrogen, heating the activated polyester solution to 80-90 ℃, and dropwise adding sulfur-containing allyl ether into the activated polyester solution; Adding a catalyst into the activated polyester solution, and carrying out heat preservation reaction for 1.5-2.0 hours at 80-90 ℃ to obtain a grafting intermediate; After the reaction is finished, adding an inhibitor to inhibit double bond polymerization of the grafting intermediate, and obtaining the bridged polyester.
  6. 6. The method of producing a highly flexible polyester fluoropropene dispersion according to claim 1, wherein said step of introducing fluoropropene gas into said reaction vessel of said bridged polyester to carry out copolymerization to obtain a copolymer comprises: after nitrogen replacement treatment is carried out on the reaction kettle where the bridging polyester is located, heating to 130-140 ℃; Introducing fluoropropene gas into the reaction kettle, and circulating the pressure in the kettle for 3-5 times within a range of 0.35-0.45 MPa; And dropwise adding a benzoyl tert-butyl peroxide initiator accounting for 0.3-0.8% of the mass of the bridged polyester into the reaction kettle for polymerization reaction to obtain a copolymer.
  7. 7. The method of preparing a highly flexible polyester fluoropropene dispersion according to claim 1, wherein said step of cooling said copolymer to a predetermined value and coating the copolymer with a surfactant comprises: cooling the copolymer to 70-80 ℃, adding polyoxyethylene alkyl ether surfactant with a hydrophilic-lipophilic balance value of 15.5-17.5 step by step, and uniformly stirring to obtain a copolymerization mixture; Carrying out high-speed shearing treatment on the copolymerization mixture, controlling the shearing rate to 7000-9000 rpm, and dispersing for 20-30 minutes to obtain initial coated particles; And carrying out coordination bond formation treatment on the initial coated particles under the conditions of pH 4.3-4.6 and temperature 70-80 ℃ to enable oxygen atoms of polyoxyethylene alkyl ether and fluorine atoms of a fluoropropene block to form coordination bonds with a distance of 1.8-2.5A, so as to generate the coated particles with hydrophilic shell layers.
  8. 8. The method of preparing a highly flexible polyester fluoropropene dispersion according to claim 1, wherein said step of shearing by slowly adding deionized water to obtain an aqueous dispersion comprises: Slowly adding deionized water into the surface coated particle system to perform primary phase transfer treatment to obtain water-in-oil emulsion; and carrying out shell layer inversion treatment on the water-in-oil emulsion at a shear rate of 6500-7500 rpm to obtain the water dispersion.
  9. 9. The method for preparing a high-flexibility polyester fluoropropene dispersion according to claim 1, wherein said step of adding tetraethoxysilane to said aqueous dispersion and performing hydrolysis treatment at a pH of 4.3 to 4.6 to obtain a high-flexibility polyester fluoropropene dispersion comprises: After the pH of the aqueous dispersion is pre-adjusted to 4.3-4.6 and the temperature is raised to 40-50 ℃, tetraethoxysilane accounting for 0.5-1.2 wt% of the total mass of the aqueous dispersion is dropwise added step by step, and meanwhile, dispersion treatment is carried out at the stirring speed of 200-300 rpm, so that a silane hydrolysis starting system is obtained; and (3) carrying out hydrolysis treatment on the silane hydrolysis starting system under the condition of nitrogen protection and temperature gradient rising from 40-50 ℃ to 60-70 ℃ to obtain the high-flexibility polyester fluoropropene dispersion.
  10. 10. A highly flexible polyester fluoropropene dispersion prepared by the process of preparing a highly flexible polyester fluoropropene dispersion according to any one of claims 1 to 9.

Description

High-flexibility polyester fluoropropene dispersoid and preparation method thereof Technical Field The invention relates to the technical field of high polymer materials, in particular to a high-flexibility polyester fluoropropene dispersoid and a preparation method thereof. Background In the prior art, polyester dispersoid is an aqueous coating material, and is applied to the fields of construction, automobiles, electronics and the like, and the preparation of the polyester dispersoid comprises the synthesis, modification and dispersion processes of polyester resin. In the preparation process of the existing polyester fluoropropene dispersion, a direct copolymerization or simple emulsification dispersion mode is generally adopted to mix and react the fluoropropene monomer and the polyester component to form a fluorine-containing polymer water dispersion system. The method combines the weather resistance of fluorine element and the film forming property of polyester through the random distribution of fluorine propylene monomer in polyester matrix and the auxiliary stabilization of surfactant. However, with increasing requirements of application scenes on flexibility of materials, such as flexible electronic substrates or flexible coatings, the fluoropropene components in the prior art have poor compatibility in polyester matrixes, so that the flexibility of the dispersion after film formation is insufficient, and the coatings are easy to crack. In particular, during the copolymerization process, the fluoropropene monomers, due to their low surface energy and high hydrophobicity, tend to form microphase separation regions between the polyester segments which induce internal stress concentrations as the dispersion dries into a film. When the coating is subjected to external force bending or thermal expansion and contraction, the microphase separation areas become stress weak points, so that crack propagation is initiated, and finally, the coating cracks and fails. Therefore, a new preparation method is needed to overcome the flexibility defect caused by poor fluoropropene compatibility and realize the balance of high elongation at break and weather resistance of the dispersion. Disclosure of Invention The invention mainly aims to provide a preparation method of a high-flexibility polyester fluoropropene dispersion, and aims to solve the technical problems of poor compatibility between a fluoropropene component and a polyester matrix and insufficient flexibility of the dispersion after film formation in the prior art. In order to solve the above problems, the present invention proposes a process for preparing a highly flexible polyester fluoropropene dispersion, comprising: Taking linear saturated polyester diol, adding an activating agent to activate the end group of the polyester main chain, and adding a catalyst to graft to obtain bridged polyester; introducing fluoropropene gas into the reaction kettle of the bridged polyester for copolymerization treatment to obtain a copolymer; Cooling the copolymer to a preset value, adding a surfactant to coat the copolymer, and slowly adding deionized water to perform shearing treatment to obtain an aqueous dispersion; And adding tetraethoxysilane into the water dispersion, and performing hydrolysis treatment under the condition of pH 4.3-4.6 to obtain the high-flexibility polyester fluoropropene dispersion. Further, the activator is any one of diphenyl phosphate, xylene phosphate or triphenyl phosphate. Further, the catalyst is any one of diphenyl phosphine, triphenylphosphine or tributylphosphine. Further, the step of adding an activator to the linear saturated polyester diol to perform end group activation treatment on the polyester main chain comprises the following steps: Pre-dehydrating the linear saturated polyester diol for 1-2 hours under the conditions of vacuum degree of-0.08 to-0.10 MPa and temperature of 100-110 ℃ to obtain dehydrated polyester diol; Under the protection of nitrogen, adding an activator containing phenyl phosphate groups into the dehydrated polyester diol step by step, stirring uniformly, and heating to 110-120 ℃ for reaction to obtain double-active-end polyester; and cooling the double-active-end polyester to 60-65 ℃ and then filtering to obtain an activated polyester solution. Further, the step of adding a catalyst for grafting treatment to obtain bridged polyester comprises the following steps: Under the protection of nitrogen, heating the activated polyester solution to 80-90 ℃, and dropwise adding sulfur-containing allyl ether into the activated polyester solution; Adding a catalyst into the activated polyester solution, and carrying out heat preservation reaction for 1.5-2.0 hours at 80-90 ℃ to obtain a grafting intermediate; After the reaction is finished, adding an inhibitor to inhibit double bond polymerization of the grafting intermediate, and obtaining the bridged polyester. Further, the step of introducing fluoropropene gas in