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CN-122011393-A - Vinyl silicone oil and preparation method thereof

CN122011393ACN 122011393 ACN122011393 ACN 122011393ACN-122011393-A

Abstract

The invention discloses vinyl silicone oil and a preparation method thereof, and belongs to the technical field of organic silicon materials. The preparation method comprises the steps of vacuum molecular distillation and purification of raw materials, preparation of bidentate carboxylate ligand by hydroxy-carboxyl bidentate substituted aromatic acid, ion exchange with P 5 + Cl ‑ to prepare a P 5 + -L catalyst, ring-opening copolymerization of D 4 、D 4 Vi and a blocking agent, glacial acetic acid quenching, stepped vacuum devolatilization and filtration to obtain a product, wherein the product is applied to the fields of high-end electronics, medical use and the like. The invention provides a bidentate ligand phosphazene salt catalytic system for solving the defects of poor selectivity, uneven vinyl distribution and high residue of a product in the prior art, realizes monomer selective polymerization by the synergistic effect of bidentate coordination and anions and cations, solves the problems of continuous block of MeViSiO units, metal residue and excessive volatile impurities, has high purity and stable performance, and meets the requirements of high-end fields.

Inventors

  • ZHOU LIANG
  • RAO JIANHUA
  • WANG YANG
  • WANG RUHUA
  • SHEN XIAOWEN

Assignees

  • 江西科睿新材料有限公司

Dates

Publication Date
20260512
Application Date
20260330

Claims (8)

  1. 1. The invention discloses vinyl silicone oil and a preparation method thereof, and belongs to the technical field of organic silicon materials. The preparation method comprises the steps of vacuum molecular distillation and purification of raw materials, preparation of bidentate carboxylate ligand by hydroxy-carboxyl bidentate substituted aromatic acid, ion exchange with P 5 + Cl - to prepare a P 5 + -L catalyst, ring-opening copolymerization of D 4 、D 4 Vi and a blocking agent, glacial acetic acid quenching, stepped vacuum devolatilization and filtration to obtain a product, wherein the product is applied to the fields of high-end electronics, medical use and the like. The invention provides a bidentate ligand phosphazene salt catalytic system for solving the defects of poor selectivity, uneven vinyl distribution and high residue of a product in the prior art, realizes monomer selective polymerization by the synergistic effect of bidentate coordination and anions and cations, solves the problems of continuous block of MeViSiO units, metal residue and excessive volatile impurities, has high purity and stable performance, and meets the requirements of high-end fields.
  2. 2. A method for preparing vinyl silicone oil according to claim 1, comprising the steps of: S1, pretreatment of raw materials: Respectively purifying octamethyl cyclotetrasiloxane, 1,3,5, 7-tetramethyl-1, 3,5, 7-tetravinyl cyclotetrasiloxane and 1, 3-divinyl tetramethyl disiloxane by vacuum molecular distillation at a distillation temperature of 95-125 ℃, a vacuum degree of 1-4Pa and a distillation rate of 4-9mL/h, wherein the water content of the purified raw materials is less than 40ppm; s2, preparing a multi-active-center organic phosphazene salt catalyst: S201, reacting phosphorus pentachloride and tris (dimethylamino) phosphorus in a molar ratio of 1 (9.5-10.5) in anhydrous toluene at a low temperature of-25 to-15 ℃ for 0.5-1h, heating to room temperature, refluxing for 65-75h, cooling, filtering to remove precipitate, decompressing, distilling to remove solvent and excessive raw materials, washing with anhydrous diethyl ether for 3 times, and vacuum drying for 4-6h to obtain white P 5 + Cl - solid; s202, reacting a substituted aromatic acid containing a hydroxyl-carboxyl bidentate structure with sodium carbonate according to a molar ratio of 1 (1.0-1.05) in absolute ethyl alcohol for 1.5-2.5 hours at room temperature, filtering, collecting precipitate, washing with absolute ethyl alcohol for 2 times, and vacuum drying for 6-8 hours to obtain a bidentate carboxylate ligand Na + L - ; S203, under the anhydrous and anaerobic condition, carrying out ion exchange reaction on P 5 + Cl - and Na + L - in a molar ratio of 1 (1.05-1.15) in anhydrous tetrahydrofuran at 20-30 ℃ for 2.5-3.5 hours, filtering to remove sodium chloride solid, removing solvent under reduced pressure, adding methyl tertiary butyl ether, crystallizing at-10-5 ℃ for 12-16 hours, filtering, and vacuum drying for 6-8 hours to obtain a P 5 + -L catalyst; s3, polymerization reaction: In a stainless steel reaction kettle protected by nitrogen, adding pretreated raw materials according to the molar ratio of octamethyl cyclotetrasiloxane, 1,3,5, 7-tetramethyl-1, 3,5, 7-tetravinyl cyclotetrasiloxane to 1, 3-divinyl tetramethyl disiloxane=100 (1.2-11) (0.6-6), heating to 65-95 ℃, adding a P 5 + -L catalyst accounting for 0.015-0.12% of the total mass of the monomers, stirring and reacting for 3-7h, wherein the pressure of a reaction system is 0.12-0.28MPa; S4, post-processing: Adding 0.05-0.15mL/g glacial acetic acid of monomer into the reaction system, stirring for 15-25min, performing step vacuum devolatilization, cooling to room temperature, and filtering with 0.22 μm polytetrafluoroethylene filter membrane to obtain high-selectivity vinyl silicone oil.
  3. 3. The method for preparing vinyl silicone oil according to claim 2, wherein the substituted aromatic acid containing a hydroxy-carboxyl bidentate structure in S202 is one of 5-methyl salicylic acid, 5-methoxy salicylic acid or 3-hydroxy-4-methoxy benzoic acid.
  4. 4. The method for preparing vinyl silicone oil according to claim 2, wherein the pKa value of the catalyst P 5 + -L in S203 is 22.8-23.6, and the thermal decomposition temperature is not less than 130 ℃.
  5. 5. The preparation method of vinyl silicone oil according to claim 2, wherein anhydrous toluene and anhydrous tetrahydrofuran in S2 are recovered by rectification, the recovery rate can reach more than 90% and more than 85%, and sodium chloride solid produced by filtration is recovered according to industrial salt standard after washing and drying.
  6. 6. The preparation method of vinyl silicone oil according to claim 2, wherein the step vacuum devolatilization specific process in S4 is that devolatilization is carried out for 1.5 hours under 115-125 ℃ and vacuum degree less than or equal to 150Pa, and after sampling and detecting that the total content of volatile cyclosiloxane (D 3 -D 6 ) is less than or equal to 0.2%, the temperature is raised to 135-145 ℃ and devolatilization is carried out for 2.5-3.5 hours under vacuum degree less than or equal to 80 Pa.
  7. 7. A multi-active center organic phosphazene salt catalyst P 5 + -L used in the preparation method as claimed in claim 2, wherein P 5 + is an aromatic carboxylate with a cation core of tetra [ tri (dimethylamino) imino ] phosphonium and L-is an anion containing a hydroxyl-carboxyl bidentate coordination structure, and the catalyst realizes the selective polymerization of octamethyl cyclotetrasiloxane and 1,3,5, 7-tetramethyl-1, 3,5, 7-tetravinyl cyclotetrasiloxane monomers by combining steric effect and electronic effect through the synergistic coordination of hydroxyl and carboxyl in a bidentate ligand, and inhibits the continuous insertion of MeViSiO units.
  8. 8. Use of the vinyl silicone oil according to claim 1 for the preparation of high-end electronic potting adhesive, addition type liquid silicone rubber, optical lens packaging material, semiconductor chip heat dissipation material, precision mold release agent, flexible display device packaging material or medical biocompatible silicone material.

Description

Vinyl silicone oil and preparation method thereof Technical Field The invention relates to the technical field of organic silicon materials, in particular to vinyl silicone oil and a preparation method thereof. Background The vinyl silicone oil is used as a core basic raw material of the addition type organic silicon material, is widely applied to high-end fields such as electronic packaging, optical devices, medical materials and the like by virtue of excellent temperature resistance, insulativity and mechanical suitability, and directly determines the crosslinking performance and use safety of downstream materials by indexes such as distribution uniformity of vinyl groups in molecular chains, product residue and the like, so that the vinyl silicone oil becomes an important point for industry research and development. At present, most of vinyl silicone oil prepared industrially takes octamethyl cyclotetrasiloxane (D 4) as a basic monomer and methyl vinyl cyclotetrasiloxane as a functional monomer and is synthesized by a ring-opening polymerization method, but in the prior art, a catalytic system generally lacks of monomer insertion selectivity, and a MeViSiO unit is easy to form a continuous block structure, so that problems of too dense local crosslinking, large brittleness, poor fatigue resistance and the like of downstream products are caused, and the use requirements of the high-end field are difficult to meet. In order to solve the problems, in the prior art, vinyl distribution is attempted to be regulated and controlled by adjusting monomer proportion, optimizing polymerization process parameters and the like, and a part of researches are carried out to replace the traditional alkali metal catalyst by using a phosphazene salt catalyst so as to reduce metal ion residues and improve polymerization controllability, and part of schemes are also attempted to introduce aromatic acid with a double-tooth structure as a ligand to prepare a modified phosphazene salt catalyst. However, the existing solution has obvious defects that firstly, the problem of monomer selective polymerization can not be solved from the catalytic mechanism level only through process adjustment, the problem of continuous MeViSiO block is not improved at all, secondly, the bidentate aromatic acid ligand used by the modified phosphazene salt catalyst is mostly a customized product, the structure selection is lack of pertinence, the synergistic coordination effect of hydroxyl and carboxyl is not fully utilized, the catalytic selectivity is improved, thirdly, the solvent recycling rate of part of the process is low, byproducts are not effectively recycled, the industrialization economy is poor, meanwhile, the volatile cyclosiloxane residue in the product is easy to exceed standard, and the method can not be suitable for severe application scenes such as medical use, flexible display and the like. Disclosure of Invention In order to solve the technical problems, the invention provides vinyl silicone oil and a preparation method thereof. The technical scheme provided by the embodiment of the invention is as follows: a preparation method of vinyl silicone oil comprises the following steps: S1, pretreatment of raw materials: Respectively purifying octamethyl cyclotetrasiloxane, 1,3,5, 7-tetramethyl-1, 3,5, 7-tetravinyl cyclotetrasiloxane and 1, 3-divinyl tetramethyl disiloxane by vacuum molecular distillation at a distillation temperature of 95-125 ℃, a vacuum degree of 1-4Pa and a distillation rate of 4-9mL/h, wherein the water content of the purified raw materials is less than 40ppm; The method comprises the steps of carrying out vacuum molecular distillation purification, wherein the core is based on the short-range molecular motion of molecular distillation and the low boiling point characteristic of vacuum environment to realize the purification and dehydration of raw materials, octamethyl cyclotetrasiloxane, 1,3,5, 7-tetramethyl-1, 3,5, 7-tetravinyl cyclotetrasiloxane and 1, 3-divinyl tetramethyldisiloxane are all organosilicon rings/oligomers, the average free path of raw material molecules is increased under the high vacuum environment of 1-4Pa at the distillation temperature of 95-125 ℃, the separation can be rapidly completed from an evaporation surface to a condensation surface, the high-temperature pyrolysis and reflux mixing of conventional distillation are avoided, the distillation rate of 4-9mL/h is controlled, the raw material molecules can be fully separated, the impurities are prevented from being co-distilled along with the raw materials, trace moisture and low boiling point light impurities in the raw materials are prevented, the boiling point is far lower than that of target raw materials under the vacuum and temperature conditions, the raw materials are preferentially separated and removed, the raw materials are enriched and finally realized on the condensation surface, the water content of the raw materials is reduced t