阅读说明：本技术 一种具有缓冲性能的超软硅烷改性聚醚胶及其制备方法 (Ultra-soft silane modified polyether adhesive with buffering performance and preparation method thereof ) 是由 许逊福 刘涛 曹阳 于 2020-06-08 设计创作，主要内容包括：一种具有缓冲性能的超软硅烷改性聚醚胶及其制备方法,利用低模量硅烷改性聚醚树脂的低硬度和异氰酸酯预聚体与空气中的湿气发生化学反应生成二氧化碳气泡,同时使用预膨胀微球三者共同作用达到了泡棉缓冲性能的水平。其中多异氰酸酯预聚体由聚醚多元醇与多异氰酸酯反应制得,由于低模量硅烷改性聚醚树脂的固化速度比异氰酸酯预聚体快,可以在胶水的表面迅速成膜,因此,生成的二氧化碳来不及逸出,形成气泡停留在固化后的胶水内,实现了缓冲效果。(The super-soft silane modified polyether adhesive with buffering performance and the preparation method thereof utilize the low hardness of low-modulus silane modified polyether resin and the chemical reaction of isocyanate prepolymer and moisture in the air to generate carbon dioxide bubbles, and simultaneously use the combined action of pre-expanded microspheres to reach the level of foam buffering performance. The low-modulus silane modified polyether resin is faster in curing speed than the isocyanate prepolymer and can quickly form a film on the surface of the glue, so that generated carbon dioxide cannot escape in time, bubbles are formed and stay in the cured glue, and the buffering effect is realized.)

1. The super-soft silane modified polyether adhesive with the buffering performance is characterized in that: the material is prepared from the following raw materials in percentage by weight:

2. the ultra-soft silane modified polyether gum with buffering property as claimed in claim 1, wherein: the low-modulus silane modified polyether resin is MAX923, MAX951 or MAX602 of Japan Bell chemical company; XM20, XM25 or STP-E10 of Wake, Germany; 1015LM and 1050MM from Meigold, USA; one or a mixture of more of the above.

3. The ultra-soft silane modified polyether gum with buffering property as claimed in claim 1, wherein: the environment-friendly plasticizer is TP-95 of the United states Rohm and Haas company; globinex W-2050 or W-2340-S from Nippon DIC; hexamoll DINCH from Pasteur, Germany; one or more of them are mixed.

4. The ultra-soft silane modified polyether gum with buffering property as claimed in claim 1, wherein: the molecular weight of the hydrophilic polyether polyol is 4000-10000.

5. The ultra-soft silane modified polyether gum with buffering property as claimed in claim 1, wherein: the pre-expanded microspheres are wrapped gas microspheres.

6. The method for preparing the ultra-soft silane modified polyether gum with the buffering property as claimed in any one of claims 1 to 5, wherein:

the method comprises the following steps: under the conditions of vacuum and drying, hydrophilic polyether glycol is reacted with polyisocyanate to synthesize an isocyanate prepolymer:

step two: and (3) under vacuum and drying conditions, stirring and mixing the product obtained in the step one with low-modulus silane modified polyether resin, an environment-friendly plasticizer, pre-expanded microspheres, a dehydrating agent, a silane coupling agent, a catalyst and fumed silica, and sealing and vacuum packaging.

7. The method for preparing the ultra-soft silane modified polyether gum with the buffering property as claimed in claim 6, wherein the method comprises the following steps:

the method comprises the following steps: sequentially adding hydrophilic polyether polyol, an environment-friendly plasticizer and fumed silica into a stirrer, controlling the temperature at 110-120 ℃, vacuumizing until the vacuum degree is-0.08-0.05 MPa, and stirring at 50-100 revolutions per minute until the water content is less than 300 ppm;

step two: reducing the temperature to 80 ℃, adding polyisocyanate, and reacting for 3 hours under the vacuum condition; then reducing the temperature to below 30 ℃, adding the low-modulus silane modified polyether resin, the dehydrating agent and the silane coupling agent into a stirrer, controlling the temperature to be 20-30 ℃, vacuumizing until the vacuum degree is-0.08-0.05 MPa, stirring for 0.5-1 hour at 200-500 r/min, and uniformly stirring;

step three: and finally, adding the catalyst into a stirrer, controlling the temperature at 20-30 ℃, vacuumizing to the vacuum degree of-0.08-0.05 MPa, stirring for 0.5-1 hour at 50-100 revolutions per minute, uniformly stirring, sealing and vacuum-packaging.

Technical Field

The invention relates to the field of adhesives, in particular to an ultra-soft silane modified polyether adhesive with buffering performance and a preparation method thereof.

Background

At present, in the field of consumer electronics, an adhesive for filling gaps mainly plays a role in filling and sealing, and during the use process of electronic products, the products fall or impact; or the collision in the transportation process of the electronic product can damage or bring damage to the electronic product, and if the adhesive filling the gap can simultaneously have a certain buffering effect, the damage condition of the electronic product under some sudden conditions can be reduced, so that the service life of the electronic product is prolonged.

The silane modified polyether adhesive (MS adhesive for short) is a high-performance environment-friendly adhesive prepared by using silyl-terminated polyether (polyether is used as a main chain, and both ends of the silyl-terminated polyether are blocked by siloxane) as a basic polymer, and has excellent mechanical strength, coating property and stain resistance, and isocyanate and organic solvents are not contained in the product. The silane modified polyether adhesive can realize crosslinking or curing through continuous exposure to moisture, and is also very convenient to use. Based on the above advantages, MS glue is often used as a gap filling adhesive in the field of electronic products.

However, the hardness of the MS glue in the field is high, and the buffering effect is limited; if other types of adhesives are adopted for replacement, for example, the silica gel has the problem of harsh curing conditions, and the silica gel needs to be baked at a high temperature of 120 ℃ for 1 hour for curing, so that the method is not suitable for the production of electronic products; the UV glue has the problems that the shadow part can not be cured and the curing depth is insufficient, and is not suitable for the field of high-precision electronic products; in addition, the foam filling is limited in shape, and the foam is difficult to apply to irregular gaps because the foam is more round and regular in shape.

Based on the situation, the development of the glue which has fluidity before curing and super-soft performance after curing is of practical significance and has wide application prospect. The lowest hardness of the silane modified polyether adhesive on the market at present can only reach about 10A (Shore A durometer), but cannot meet the requirement of ultra-soft; according to the relevant test results of electronic products, the hardness needs to reach below 10oo (shore oo durometer) to play a role in buffering under the condition that the glue thickness is thinner (0.2 mm).

Disclosure of Invention

The invention aims to provide an ultra-soft silane modified polyether adhesive with good buffering performance and a preparation method thereof.

In order to achieve the above purpose, the solution of the invention is:

the super-soft silane modified polyether adhesive with the buffering performance is characterized in that: the material is prepared from the following raw materials in percentage by weight:

further, the low-modulus silane modified polyether resin is MAX923, MAX951 or MAX602 of Japan Bell chemical company; XM20, XM25 or STP-E10 of Wake, Germany; 1015LM and 1050MM from Meigold, USA; one or a mixture of more of the above.

Further, the environment-friendly plasticizer is TP-95 of Rohm and Haas company in America; GlobinexW-2050 or W-2340-S from Nippon DIC; hexamoll DINCH from Pasteur, Germany; one or more of them are mixed.

Furthermore, the molecular weight of the hydrophilic polyether polyol is 4000-10000.

Further, the pre-expanded microspheres are encapsulated gas microspheres.

The preparation method of the ultra-soft silane modified polyether adhesive with the buffering performance comprises the following specific steps:

the method comprises the following steps: under the conditions of vacuum and drying, hydrophilic polyether glycol is reacted with polyisocyanate to synthesize an isocyanate prepolymer:

step two: and (3) under vacuum and drying conditions, stirring and mixing the product obtained in the step one with low-modulus silane modified polyether resin, an environment-friendly plasticizer, pre-expanded microspheres, a dehydrating agent, a silane coupling agent, a catalyst and fumed silica, and sealing and vacuum packaging.

The preparation method of the super-soft silane modified polyether adhesive with the buffering performance comprises the following specific steps:

the method comprises the following steps: sequentially adding hydrophilic polyether polyol, an environment-friendly plasticizer and fumed silica into a stirrer, controlling the temperature at 110-120 ℃, vacuumizing until the vacuum degree is-0.08-0.05 MPa, and stirring at 50-100 revolutions per minute until the water content is less than 300 ppm;

step two: reducing the temperature to 80 ℃, adding polyisocyanate, and reacting for 3 hours under the vacuum condition; then reducing the temperature to below 30 ℃, adding the low-modulus silane modified polyether resin, the dehydrating agent and the silane coupling agent into a stirrer, controlling the temperature to be 20-30 ℃, vacuumizing until the vacuum degree is-0.08-0.05 MPa, stirring for 0.5-1 hour at 200-500 r/min, and uniformly stirring;

step three: and finally, adding the catalyst into a stirrer, controlling the temperature at 20-30 ℃, vacuumizing to the vacuum degree of-0.08-0.05 MPa, stirring for 0.5-1 hour at 50-100 revolutions per minute, uniformly stirring, sealing and vacuum-packaging.

After the scheme is adopted, the low-modulus silane modified polyether resin is high in curing speed, when the isocyanate prepolymer formed by the reaction of the hydrophilic polyether polyol and the polyisocyanate and moisture in the air are subjected to chemical reaction to generate carbon dioxide, the low-modulus silane modified polyether resin is higher in curing speed than the isocyanate prepolymer and can quickly form a film on the surface of the glue, so that the generated carbon dioxide cannot escape in time, bubbles are formed and stay in the cured glue, and the buffering effect is realized; meanwhile, the existence of the expanded microspheres further improves the overall buffer performance of the glue.

Detailed Description

The patent has better buffering performance based on the following reasons:

firstly, the method comprises the following steps: the low modulus silane modified polyether resin is used (the low modulus resin has low hardness), no filler is used (the filler increases the system hardness and is not used), and the low modulus silane modified polyether resin can be cured quickly.

II, secondly: a large amount of environment-friendly plasticizers are used, and the environment-friendly plasticizers refer to low-toxicity substances which can increase the plasticity of high polymer materials. The environment-friendly plasticizer is characterized in that molecules of the environment-friendly plasticizer are inserted among molecular chains of a high-molecular polymer, so that the attractive force among the molecular chains of the polymer is weakened, namely, the aggregation effect among the molecular chains is weakened, the mobility and the flexibility of the molecular chains are increased, and the plasticity is increased. And the environment-friendly plasticizer does not participate in the reaction, so that the crosslinking degree of the system is reduced, and the hardness of the glue can be reduced.

Thirdly, the method comprises the following steps: the addition of the pre-expanded microspheres, which consist of a polymer shell and gas surrounding it, has a high resilience. The pre-expanded microspheres are easily compressed and, after the pressure is released, the microspheres easily return to their original volume. The pre-expanded microspheres are excellent in resilience so that they can withstand multiple pressurization/depressurization without rupture. This makes the glue with the added expanded microspheres a good impact absorbing material.

Fourthly, the method comprises the following steps: reacting hydrophilic polyether polyol with polyisocyanate to form isocyanate prepolymer; when the isocyanate prepolymer is used, the isocyanate prepolymer can react with moisture in the air to generate carbon dioxide, and the following equation is given:

OCN-R-NCO+2H₂O→H₂N-R-NH₂+CO₂↑

bubble generation principle of isocyanate prepolymer

When the low-modulus silane modified polyether resin is used, the curing speed of the low-modulus silane modified polyether resin is higher than that of the isocyanate prepolymer, so that a film can be quickly formed on the surface of the glue, carbon dioxide generated by the isocyanate prepolymer cannot escape in time to form bubbles, and the overall buffer performance of the glue is further improved.

The silane coupling agent is one or a mixture of aminosilane, epoxy silane, methacryloxy silane and mercapto silane.

The fumed silica is one or a mixture of more of R972 of winning company, MA100 of Mitsubishi company, TS-720 of Cabot company and N20 of Wack company.

The low-modulus silane modified polyether resin is MAX923, MAX951 or MAX602 of Japan Bell chemical company; XM20, XM25 or STP-E10 of Wake, Germany; 1015LM and 1050MM from Meigold, USA; one or a mixture of more of the above.

The polyisocyanate is one or a mixture of more of toluene diisocyanate, diphenyl methyl diisocyanate, 1, 6-hexamethylene diisocyanate, 1, 12-dodecane diisocyanate, cyclohexane-1, 3-diisocyanate, cyclobutane-1, 3-diisocyanate, cyclohexane-1, 3-diisocyanate, hexahydro-1, 3-phenylene diisocyanate, hexahydro-1, 4-phenylene diisocyanate, hydrogenated-2, 4-diphenylmethane diisocyanate, hydrogenated-4, 4-diphenylmethane diisocyanate, p-phenylene diisocyanate, toluene-2, 6-diisocyanate and toluene-2, 4-diisocyanate; diphenylmethyl diisocyanate is preferred.

The environment-friendly plasticizer is TP-95 of the United states Rohm and Haas company; globinex W-2050 or W-2340-S from Nippon DIC; hexamoll DINCH from Pasteur, Germany; one or more of them are mixed.

The dehydrating agent is one or a mixture of more of vinyltrimethoxysilane, vinyltriethoxysilane, vinyldimethoxysilane and vinyldiethoxysilane.

The catalyst is one or a mixture of several of an organic tin catalyst, an organic bismuth catalyst and an amine catalyst. As characterized in the following examples: