阅读说明：本技术 一种硅烷改性聚醚防火密封胶及其制备方法 (Silane modified polyether fireproof sealant and preparation method thereof ) 是由 郑品 李义博 杨海兵 李震 于 2020-05-27 设计创作，主要内容包括：本发明提供一种硅烷改性聚醚防火密封胶及其制备方法,该密封胶包括如下重量份的原料：树脂预混料50～75份、阻燃剂0～15份、防火阻燃填料0～15份、陶瓷化助剂0～15份、除水剂0～3份、偶联剂0.1～3份、催化剂0.1～2份,所述阻燃剂包括膨胀型阻燃剂,所述防火阻燃填料包括煅烧高岭土,所述陶瓷化助剂包括硼酸锌；所述膨胀型阻燃剂、煅烧高岭土和硼酸锌的质量比例为1：x：y,其中1.5＜x＜3,0.5＜y＜1。本发明通过在密封胶中搭配IFR阻燃剂、煅烧高岭土和硼酸锌,并将三者比例控制在合适范围内,有效提高密封胶对超高温下的耐受能力,同时阻燃剂用量较低使得密封胶能够保持低模量高位移能力。(The invention provides a silane modified polyether fireproof sealant and a preparation method thereof, wherein the sealant comprises the following raw materials in parts by weight: 50-75 parts of resin premix, 0-15 parts of flame retardant, 0-15 parts of fireproof flame-retardant filler, 0-15 parts of ceramic assistant, 0-3 parts of water removing agent, 0.1-3 parts of coupling agent and 0.1-2 parts of catalyst, wherein the flame retardant comprises intumescent flame retardant, the fireproof flame-retardant filler comprises calcined kaolin, and the ceramic assistant comprises zinc borate; the mass ratio of the intumescent flame retardant to the calcined kaolin to the zinc borate is 1: x: y, wherein x is more than 1.5 and less than 3, and y is more than 0.5 and less than 1. According to the invention, the IFR flame retardant, the calcined kaolin and the zinc borate are matched in the sealant, and the proportion of the IFR flame retardant, the calcined kaolin and the zinc borate is controlled within a proper range, so that the tolerance capability of the sealant under the ultra-high temperature is effectively improved, and meanwhile, the sealant can keep the low-modulus high-displacement capability due to the low dosage of the flame retardant.)

1. A silane modified polyether fireproof sealant is characterized in that: the feed comprises the following raw materials in parts by weight:

50-75 parts of resin premix

0-15 parts of fire retardant

0-15 parts of fireproof flame-retardant filler

0-15 parts of ceramic assistant

0 to 3 parts of water removing agent

0.1-3 parts of coupling agent

0.1-2 parts of catalyst

The weight parts of the flame retardant, the fireproof flame-retardant filler and the ceramic auxiliary agent are all not 0; the flame retardant comprises an intumescent flame retardant, the fireproof flame-retardant filler comprises calcined kaolin, and the ceramization assistant comprises zinc borate; the mass ratio of the intumescent flame retardant to the calcined kaolin to the zinc borate is 1: x: y, wherein x is more than 1.5 and less than 3, and y is more than 0.5 and less than 1.

2. The silane-modified polyether fire retardant sealant according to claim 1, wherein: the resin premix comprises the following raw materials in parts by weight:

10-30 parts of silane modified polyether resin

5-15 parts of plasticizer

10-20 parts of reinforcing filler

0-5 parts of thixotropic agent

0-5 parts of antioxidant

0-5 parts of ultraviolet absorber

0-3 parts of pigment.

3. The silane-modified polyether fire retardant sealant according to claim 2, characterized in that: the silane modified polyether resin is selected from silane terminated polyether with hydrolysable terminal group, and the viscosity is 3000-50000 cps at 20 ℃.

4. The silane-modified polyether fire retardant sealant according to claim 2, characterized in that: the plasticizer is at least one of diisononyl phthalate, diisodecyl phthalate and diphenyl isodecyl phosphate.

5. The silane-modified polyether fire retardant sealant according to claim 2, characterized in that: the reinforcing filler is at least one selected from nano calcium carbonate, light calcium carbonate, heavy calcium carbonate and aluminum hydroxide.

6. The silane-modified polyether fire retardant sealant according to claim 2, characterized in that: the thixotropic agent is selected from polyamide wax and/or hydrogenated castor oil.

7. The silane-modified polyether fire retardant sealant according to claim 2, characterized in that: the antioxidant is at least one selected from the group consisting of pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ], isooctyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate and ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate ].

8. The silane-modified polyether fire retardant sealant according to claim 1, wherein: the coupling agent is at least one selected from gamma-aminopropyltrimethoxysilane, N-beta- (aminoethyl) -gamma-aminopropylmethyldimethoxysilane, gamma-glycidoxypropyltrimethoxysilane and gamma-methacryloxypropyltrimethoxysilane.

9. A preparation method of the silane modified polyether fireproof sealant as claimed in any one of claims 1 to 8 is characterized in that: the method comprises the following steps: adding a flame retardant, a fireproof flame-retardant filler and a ceramic auxiliary agent into the resin premix, then adding a water removing agent, a coupling agent and a catalyst, stirring, defoaming and discharging to obtain the flame-retardant resin premix.

10. The method of claim 9, wherein: the preparation method of the resin premix comprises the following steps: mixing silane modified polyether resin, a plasticizer, a reinforcing filler, a thixotropic agent, an antioxidant, an ultraviolet absorbent and a filler to obtain a resin premix.

Technical Field

The invention belongs to the technical field of sealants, and particularly relates to a silane modified polyether fireproof sealant and a preparation method thereof.

Background

The current sealing gum for the assembly type housing industry is mainly modified polyether sealing gum, polyurethane sealing gum, silicone sealing gum and the like, wherein the modified polyether sealing gum has more excellent comprehensive performance and the largest consumption. Mechanical property and fireproof performance are two important opposite sides of the investigation of the sealant, however, a great deal of research finds that the flame-retardant material can generate negative effects on the tensile strength, flexibility and the like of the sealant, so that most of the sealants can not simultaneously meet the requirements of the mechanical property (25LM) and the fireproof performance.

For example, in patent 201310294489.3, flame retardant fillers such as aluminum hydroxide, magnesium hydroxide, zinc oxide, zinc borate, etc. are added to the resin to solve the problem of burning of the one-component silane modified polyether sealant, and improve the flame retardant property of the one-component silane modified polyether sealant, however, the one-component silane modified polyether sealant still ashes like a common sealant and loses the plugging effect under continuous flame burning. And the mechanical properties of the material can be greatly reduced due to the addition of a large amount of inorganic flame retardant, the tensile strength, the elongation at break, the flexibility and the like of the material are gradually reduced along with the increase of the dosage of the flame retardant, and the requirements of low modulus and high displacement on the mechanical properties cannot be met. Meanwhile, the flame-retardant filler can cause the thickening problem after the sealant, so that the extrudability is poor and the quality guarantee period is shortened. Patent 201910467785.6 is poor in mechanical property after adding a flame retardant, generally 7.5P, and cannot meet the requirement of 25LM mechanical property in the assembled housing industry. The single-component silane modified polyether sealant provided by patent 201711267069.0 realizes the effect of low modulus and high resilience, but does not have fireproof performance.

Disclosure of Invention

The invention aims to provide a silane modified polyether fireproof sealant and a preparation method thereof, and the sealant can have excellent low-modulus high-displacement capacity and fireproof performance.

The purpose of the invention is realized by the following technical scheme:

the silane modified polyether fireproof sealant comprises the following raw materials in parts by weight:

50-75 parts of resin premix

0-15 parts of fire retardant

0-15 parts of fireproof flame-retardant filler

0-15 parts of ceramic assistant

0 to 3 parts of water removing agent

0.1-3 parts of coupling agent

0.1-2 parts of catalyst

The weight parts of the flame retardant, the fireproof flame-retardant filler and the ceramic auxiliary agent are all not 0; the flame retardant comprises an intumescent flame retardant (IFR flame retardant), the fireproof flame-retardant filler comprises calcined kaolin, and the ceramization assistant comprises zinc borate; the mass ratio of the IFR flame retardant to the calcined kaolin to the zinc borate is 1: x: y, wherein x is more than 1.5 and less than 3, and y is more than 0.5 and less than 1.

The resin premix comprises the following raw materials in parts by weight:

10-30 parts of silane modified polyether resin

5-15 parts of plasticizer

10-20 parts of reinforcing filler

0-5 parts of thixotropic agent

0-5 parts of antioxidant

0-5 parts of ultraviolet absorber

0-3 parts of pigment.

The silane modified polyether resin is selected from silane terminated polyether with hydrolysable terminal group, and the viscosity is 3000-50000 cps at 20 ℃.

The structural formula of the terminal hydrolysable silane-terminated polyether is as follows:

wherein R is₂Is R₁OR OR₁，R₁Selected from methyl or ethyl.

The plasticizer is at least one of diisononyl phthalate, diisodecyl phthalate and diphenyl isodecyl phosphate.

The reinforcing filler is at least one selected from nano calcium carbonate, light calcium carbonate, heavy calcium carbonate and aluminum hydroxide.

The thixotropic agent is selected from polyamide wax and/or hydrogenated castor oil.

The antioxidant is selected from at least one of pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] (preferably IRGANOX1010), isooctyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate (preferably IRGANOX1135), and ethylene bis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate ] (preferably IRGANOX 245).

The ultraviolet absorbent is at least one selected from TINUVIN326, TINUVIN328, TINUVIN329, TINUVIN571, TINUVIN123, TINUVIN622, TINUVIN765, TINUVIN770, TINUVIN292, TINUVIN791 and TINUVIN 944.

The pigment is at least one selected from titanium dioxide, carbon black and iron oxide red.

The water scavenger comprises vinyl trimethoxy silane.

The coupling agent is at least one selected from gamma-aminopropyltrimethoxysilane, N-beta- (aminoethyl) -gamma-aminopropylmethyldimethoxysilane, gamma-glycidoxypropyltrimethoxysilane and gamma-methacryloxypropyltrimethoxysilane.

The catalyst is at least one of stannous octoate, dibutyltin dilaurate and di-n-butyl bis (acetylacetonato) tin.

A preparation method of silane modified polyether fireproof sealant comprises the following steps: adding a flame retardant, a fireproof flame-retardant filler and a ceramic auxiliary agent into the resin premix according to a proportion, then adding a water removing agent, a coupling agent and a catalyst, stirring, defoaming and discharging to obtain the flame-retardant fire.

The preparation method of the resin premix comprises the following steps: mixing silane modified polyether resin, a plasticizer, a reinforcing filler, a thixotropic agent, an antioxidant, an ultraviolet absorbent and a filler in proportion, heating to 105-115 ℃, dehydrating at a constant temperature for 2-3 h, stirring by a dispersion plate at a high speed of 1000r/min in the dehydration process, and keeping the vacuum degree at-0.09-0.1 Mpa to obtain the resin premix.

The silane modified polyether resin, the plasticizer, the reinforcing filler, the thixotropic agent, the antioxidant, the ultraviolet absorbent and the filler are mixed and then heated to 105-115 ℃ and dehydrated at constant temperature for 2-3 hours.

And carrying out high-speed stirring in the dehydration process, wherein the high-speed stirring speed is 500-1500 r/min, and preferably 1000 r/min.

Compared with the prior art, the IFR flame retardant, the calcined kaolin and the zinc borate are matched in the sealant, the proportion of the IFR flame retardant, the calcined kaolin and the zinc borate is controlled within a proper range, the tolerance capability of the sealant under the ultrahigh temperature is effectively improved, and meanwhile, the low dosage of the flame retardant enables the sealant to keep the low-modulus high-displacement capability.

Specifically, in the invention, the IFR flame retardant is an integrated flame retardant powder composed of APP (ammonium polyphosphate) + PER (pentaerythritol) + MEL (melamine), and the chemical structural formula of the IFR flame retardant is as follows:

when heated, the IFR flame retardant releases a large amount of nontoxic gas capable of inhibiting flame spread, and expands to form a foam carbon layer for insulating heat.

The chemical components of the calcined kaolin are as follows: al (Al)₂O₃＞43％，SiO₂The coating has a silicon-oxygen tetrahedral layer microstructure of 50-54%, is compact and stable in structure, high in temperature resistance and free from collapse at high temperature. Different from the common filler (nano calcium, heavy calcium, light calcium and the like), the foam carbon layer is easy to collapse at the ultra-high temperature (1000 ℃), the calcined kaolin can provide framework support for the foam carbon layer formed by the IFR flame retardant at the ultra-high temperature (1000 ℃), and the problems that the foam carbon layer formed when the IFR flame retardant is used alone is weak in strength and easy to collapse, the foam carbon layer only can tolerate the temperature of 200-300 ℃, and the foam carbon layer cannot tolerate the ultra-high temperature (1000 ℃). Meanwhile, the calcined kaolin has certain flame retardant property, and the addition amount of the IFR flame retardant can be reduced. The less the consumption of the flame retardant is, the less the influence on the mechanical property of the sealant is, and the preparation of the low-modulus (25LM) silane modified polyether sealant is more facilitated.

Boric acidThe chemical composition of zinc is mainly 2ZnO 3B₂O₃And the ZnO content is more than 46 percent. Boron oxygen trigone [ B ] in zinc borate at high temperature₂O₃]The boron structure is converted into a boron-oxygen tetrahedron, so that the boron structure is converted from a layered or chain structure to a framework structure; while following a portion B₂O₃The zinc borate can form a stable char forming agent to promote the IFR flame retardant system to form char into a foamy carbon layer; the zinc borate is melted at the temperature of over 600 ℃ to form a vitrified ceramic layer, and the vitrified ceramic layer is coated on the surface of the foam carbon layer, so that the strength and hardness of the foam carbon layer are improved, and support is provided for enduring the ultrahigh temperature for a long time (4 h). Through research, residues formed by melting the zinc borate still retain relatively high strength and hardness after the zinc borate is tested by a muffle furnace at 1000 ℃/4 h.

Drawings

FIG. 1 is a fire performance test procedure;

FIG. 2 is a morphological diagram of the sealants of examples 1-3 and comparative examples 1-3 before and after the tests on the fireproof performance;

FIG. 3 is a morphological diagram of the sealants of comparative examples 4-8 before and after the tests on the fireproof performance.

Detailed Description

The technical solution of the present invention is further illustrated by the following specific examples.