阅读说明：本技术 一种烷氧基封端有机硅聚醚共聚物的合成方法及其密封胶的制备 (Synthesis method of alkoxy-terminated organic silicon polyether copolymer and preparation of sealant thereof ) 是由 代振楠 王建斌 陈田安 于 2020-05-18 设计创作，主要内容包括：本发明公开了一种烷氧基封端有机硅聚醚共聚物的合成及其密封胶的制备。烷氧基封端有机硅聚醚共聚物的合成包括如下步骤：(1)将低含氢硅油、双端烯丙基聚醚与乙烯基三烷氧基硅烷加入容器,同时加入铂金催化剂；(2)对步骤(1)获得的体系进行微波处理；(3)对步骤(2)获得的体系进行减压蒸馏,得到烷氧基封端有机硅聚醚共聚物。本发明采用微波辐射方法合成树共聚物,克服了传统工艺用时长、催化剂用量大、成本高、污染环境、操作繁琐等缺点；用合成的共聚物制备密封胶时,气相法白炭黑在合成的共聚物中的分散明显优于传统MS树脂,可制备成透明低定伸应力密封胶；同时本体系采用透明钛做催化剂,外观不发黄,应用领域宽,初始粘接好。(The invention discloses synthesis of an alkoxy-terminated organic silicon polyether copolymer and preparation of a sealant thereof. The synthesis of the alkoxy-terminated silicone polyether copolymer comprises the following steps: (1) adding low-hydrogen silicone oil, double-end allyl polyether and vinyl trialkoxysilane into a container, and simultaneously adding a platinum catalyst; (2) carrying out microwave treatment on the system obtained in the step (1); (3) and (3) carrying out reduced pressure distillation on the system obtained in the step (2) to obtain the alkoxy-terminated organic silicon polyether copolymer. The invention adopts the microwave radiation method to synthesize the tree copolymer, and overcomes the defects of long time consumption, large catalyst consumption, high cost, environmental pollution, complex operation and the like of the traditional process; when the synthesized copolymer is used for preparing the sealant, the dispersion of the fumed silica in the synthesized copolymer is obviously superior to that of the traditional MS resin, and the transparent sealant with low stress at definite elongation can be prepared; meanwhile, the system adopts transparent titanium as a catalyst, so that the appearance is not yellow, the application field is wide, and the initial bonding is good.)

1. A method for synthesizing an alkoxy-terminated organic silicon polyether copolymer is characterized by comprising the following steps:

(1) adding low-hydrogen silicone oil, double-end allyl polyether and vinyl trialkoxysilane into a container, and simultaneously adding a platinum catalyst;

(2) carrying out microwave treatment on the system obtained in the step (1);

(3) and (3) carrying out reduced pressure distillation on the system obtained in the step (2) to obtain the alkoxy-terminated organic silicon polyether copolymer.

2. The synthesis method according to claim 1, wherein in the step (1), the hydrogen-low silicone oil: allyl-terminated polyether: the vinyl trialkoxysilane is prepared from (2-5): 1: (1-3); the mass ratio of the total amount of the low-hydrogen silicone oil, the double-end allyl polyether and the vinyl trialkoxysilane to the platinum catalyst is 100: (0.1-0.5).

3. The synthesis method as claimed in claim 1, wherein the microwave treatment in step (2) is carried out at a temperature of 60-100 ℃ for 1-2h and at a microwave treatment parameter of 600W.

4. The synthesis method according to claim 1, wherein the low hydrogen-containing silicone oil is a side hydrogen-containing silicone oil, and the silicon hydrogen content is 0.1 wt% to 0.2 wt%; the structural formula is as follows:

wherein x is 10-20, y is 190-.

5. The synthesis method of claim 1, wherein the allyl-terminated polyether has an allyl content of 0.82 wt% to 1.64 wt%, and has the following structural formula:

wherein m is 160-330.

6. The method of synthesis according to claim 1,

the vinyl trialkoxysilane is vinyl trimethoxy silane or vinyl triethoxy silane;

the platinum catalyst is a platinum (0) -divinyl tetramethyl disiloxane complex or a platinum (0) -vinyl amino complex; the platinum (0) -divinyltetramethyldisiloxane complex or the platinum (0) -vinylamino complex has a platinum content of 1000-5000 ppm.

7. An alkoxy-terminated silicone polyether copolymer synthesized using the synthesis method of any of claims 1-6.

8. The use of the alkoxy-terminated silicone polyether copolymer of claim 7 in the preparation of a sealant comprising the steps of:

adding 79-120 parts by weight of the alkoxy-terminated organic silicon polyether copolymer, 5-35 parts by weight of fumed silica, 0.1-2 parts by weight of light stabilizer and 0.1-2 parts by weight of antioxidant into a reaction kettle, uniformly mixing, and heating to 120 ℃ for vacuum dehydration for 2 hours; adding 0.5-8 parts of water removing agent and 1-5 parts of coupling agent, uniformly mixing, adding 0.1-1.5 parts of catalyst, vacuumizing and mixing for 15min, filling nitrogen, relieving pressure, sealing and storing.

9. Preparation according to claim 8,

the fumed silica is one or more of watt H18, cabot TS-610 and cabot TS-720;

the light stabilizer is a BASF light stabilizer 770 or a BASF light stabilizer 326;

the antioxidant is a Pasteur antioxidant 1010 or a Pasteur antioxidant 1076.

10. Preparation according to claim 8,

the water removing agent is vinyl trimethoxy silane or hexamethyldisilazane;

the coupling agent is an amino silane coupling agent;

the catalyst is transparent titanium catalyst.

Technical Field

The invention belongs to the field of modified silane adhesives, and particularly relates to a synthesis method of an alkoxy-terminated organic silicon polyether copolymer and preparation of a sealant thereof.

Background

The silane modified polyether sealant (MS sealant for short) is a high-performance sealant prepared by taking silyl-terminated polyether (polyether is taken as a main chain, and both ends of the silyl-terminated polyether are terminated by siloxane) as a basic polymer, and the unique structure of the sealant enables the MS sealant to have excellent environmental-friendly performance, wide bonding range, super-strong bonding strength, excellent overall performances of balance such as stain resistance, paintability and the like, so that the MS sealant can be widely applied to the fields of buildings and industries.

The traditional preparation method of the organic silicon polyether copolymer is that the raw materials are added into an organic solvent (benzene or toluene), the raw materials are fully dissolved under the heating condition of a water bath or an oil bath, and then a catalyst is added for reaction, so that a target product is obtained. The process has the defects of long time, large catalyst addition, high cost, environmental pollution, complex operation and the like, so that the improvement of the silicone polyether copolymerization synthesis process is urgent.

Because the polyether chain segment has regular structure and compact arrangement of the molecular chain segment, the hardness and modulus of the sealant are higher than those of organosilicon sealants, the flexibility of the sealant is poorer than that of the organosilicon sealant, the problem is solved by adding a plasticizer in the MS sealant, and the problems of precipitation and the like are caused by the increase of the plasticizer. In addition, in order to improve the curing efficiency and realize good initial adhesion performance, the MS sealant mostly adopts tin catalysts, but due to the increasing environmental requirements of people, european union resolution 2009/425/EC of 2009 limited the use of organotin compounds. In 2017, in 8 months, Changchun passenger train factories release technical specifications of forbidden substances of SJTY-ZT-003 rail transit equipment products, and the specifications also put forward new requirements for developing modified silane sealants of non-tin catalytic systems, which gradually and strictly carry out management and control on the types and the use amounts of organic tin compounds in all materials of motor train unit products and meet environmental protection requirements.

Disclosure of Invention

Aiming at the defects existing in the prior art, the invention adopts a new process to synthesize the organic silicon polyether copolymer on the basis of the prior modified silane technology, and uses an organic silicon chain segment in synthetic resin to replace a plasticizer so as to improve the flexibility of the MS sealant and reduce the stress at definite elongation. The organic silicon polyether copolymer is synthesized by adopting a microwave radiation method, and the synthesis process overcomes the defects of long time, large catalyst consumption, high cost, environmental pollution, complex operation and the like of the traditional process; when the synthesized copolymer is used for preparing the sealant, the dispersion of the fumed silica in the synthesized copolymer is obviously superior to that of the traditional MS resin, and the transparent sealant with low stress at definite elongation can be prepared; meanwhile, the system adopts transparent titanium as a catalyst, so that the appearance is not yellow, the application field is wide, and the initial bonding is good.

The specific technical scheme is as follows:

one purpose of the invention is to disclose a synthetic method of alkoxy-terminated silicone polyether copolymer.

A method for synthesizing an alkoxy-terminated organic silicon polyether copolymer comprises the following steps:

(1) adding low-hydrogen silicone oil, double-end allyl polyether and vinyl trialkoxysilane into a container, and simultaneously adding a platinum catalyst;

(2) carrying out microwave treatment on the system obtained in the step (1);

(3) and (3) carrying out reduced pressure distillation on the system obtained in the step (2) to obtain the organic silicon polyether copolymer.

Further, in the step (1), the low hydrogen-containing silicone oil, the double-end allyl polyether and the vinyl trialkoxysilane are mixed according to the molar ratio of (2-5) to (1-3).

Furthermore, the mass ratio of the total amount of the low hydrogen-containing silicone oil, the double-end allyl polyether and the vinyl trialkoxysilane to the platinum catalyst is 100: 0.1-0.5.

Further, the microwave treatment in the step (2) has the parameters of 100-600W, the temperature of 60-100 ℃, and the reaction time of 1-2 h.

Further, the low-hydrogen silicone oil is lateral hydrogen silicone oil, and the silicon hydrogen content is 0.1-0.2 wt%; the structural formula is as follows:

wherein x is 10-20, y is 190-.

Further, the allyl content of the double-end allyl polyether is 0.82 wt% -1.64 wt%, and the structural formula is as follows:

wherein m is 160-330.

Further, the vinyl trialkoxysilane is vinyl trimethoxysilane or vinyl triethoxysilane.

Further, the platinum catalyst is a platinum (0) -divinyltetramethyldisiloxane complex or a platinum (0) -vinylamino complex.

Still further, the platinum (0) -divinyltetramethyldisiloxane complex or the platinum (0) -vinylamino complex had a platinum content of 1000-5000 ppm.

Further, the reaction equation of the alkoxy-terminated silicone polyether copolymer is as follows:

the beneficial effects of the above technical scheme are: the organic silicon polyether copolymer is synthesized by a microwave radiation method, and the synthesis process does not need a solvent, and overcomes the defects of long time, large catalyst consumption, high cost, environmental pollution, complex operation and the like of the traditional process.

The invention also discloses an alkoxy-terminated organic silicon polyether copolymer obtained by the synthesis method.

The invention also discloses the preparation of the sealant, and the alkoxy-terminated silicone polyether copolymer is used.

The preparation of the sealant comprises the following components in parts by weight:

the preparation of the sealant comprises the following steps:

adding 79-120 parts of alkoxy end-capped organic silicon polyether copolymer, 5-35 parts of fumed silica, 0.1-2 parts of light stabilizer and 0.1-2 parts of antioxidant into a reaction kettle in parts by weight, uniformly mixing, and heating to 120 ℃ for vacuum dehydration for 2 hours; adding 0.5-8 parts of water removing agent and 1-5 parts of coupling agent, uniformly mixing, adding 0.1-1.5 parts of catalyst, vacuumizing and mixing for 15min, filling nitrogen, relieving pressure, sealing and storing.

Further, the fumed silica is one or more of watt H18, cabot TS-610 and cabot TS-720.

Further, the light stabilizer is a BASF light stabilizer 770 or a BASF light stabilizer 326.

Further, the antioxidant is a basf antioxidant 1010 or a basf antioxidant 1076.

Further, the water removal agent is vinyl trimethoxy silane or hexamethyl disilazane.

Further, the coupling agent is an aminosilane coupling agent. Preferably one or two of the Maifang amino silane coupling agents A-1110, A-1120 and A-2120.

Further, the catalyst is a transparent titanium catalyst. Preferably H9000 from DuPont or KRTi-1 from Kery, Inc.

The invention has the following beneficial effects:

the organic silicon polyether copolymer is synthesized by a microwave radiation method, and the synthesis process does not need a solvent, and overcomes the defects of long time, large catalyst consumption, high cost, environmental pollution, complex operation and the like of the traditional process. When the synthetic resin is used for preparing the sealant, the dispersion of the fumed silica in the synthetic resin is obviously superior to that of the traditional MS resin, and the transparent sealant with the stress at 100 percent definite elongation can be prepared without adding a plasticizer; meanwhile, the system adopts transparent titanium as a catalyst, so that the appearance is not yellow, the application field is wide, and the initial bonding is good.

Detailed Description

The principles and features of this invention are described below in conjunction with examples, which are set forth to illustrate, but are not to be construed to limit the scope of the invention.

The hydrogen-containing silicone oil used in the following examples is lateral hydrogen-containing silicone oil, the silicon hydrogen content being 0.1 wt% to 0.2 wt%; the structural formula is as follows:

wherein x is 10-20, y is 190-.

The allyl-terminated polyethers used in the examples below, having an allyl content of 0.82 to 1.64 wt%, have the following structural formula:

wherein m is 160-330.