CN114163967B

CN114163967B - Double-component pouring sealant and preparation method and application thereof

Info

Publication number: CN114163967B
Application number: CN202210051172.6A
Authority: CN
Inventors: 区炜; 刘保华; 艾娇艳; 宋丽娜
Original assignee: Guangdong University of Technology
Current assignee: Guangdong University of Technology
Priority date: 2022-01-17
Filing date: 2022-01-17
Publication date: 2023-07-18
Anticipated expiration: 2042-01-17
Also published as: CN114163967A

Abstract

The application belongs to the technical field of pouring sealants, and particularly relates to a two-component pouring sealant, and a preparation method and application thereof. The application provides a bicomponent pouring sealant soaks in weak alkaline solution such as ethanolamine, and the hydrone in the solution can adsorb on the pouring sealant molecular chain, takes place hydrolysis reaction with the ester group on the pouring sealant molecular chain, generates the short molecular chain, and the short molecular chain continues to hydrolyze into the micromolecule chain to make the bicomponent pouring sealant lose intensity, can remove, and, the pouring sealant that removes can degrade through the compost, can not cause environmental pollution, thereby solve electronic components in the prior art and can't maintain, retrieve after the pouring sealant, cause environmental pollution's technical problem easily.

Description

Double-component pouring sealant and preparation method and application thereof

Technical Field

The application belongs to the technical field of pouring sealants, and particularly relates to a two-component pouring sealant, and a preparation method and application thereof.

Background

The pouring sealant is used for bonding and sealing electronic components, and achieves the effects of dust prevention, moisture prevention, shock resistance, corrosion resistance and the like, and the current common pouring sealants comprise epoxy pouring sealants, organic silicon pouring sealants and polyurethane pouring sealants; the polyurethane contains a unique soft and hard segment phase separation structure, so that after the polyurethane pouring sealant is poured and sealed, the colloid part has good elasticity, wear resistance and impact resistance, the operation of the component in a severe environment can be ensured, and the stability and the service life of the component are improved.

However, when the electronic components after the polyurethane pouring sealant have local problems, the currently used pouring sealant cannot be degraded, so that the electronic components lose maintenance value and can only be discarded, huge waste is caused, and meanwhile, the pouring sealant cannot be degraded after the electronic components are discarded, so that environmental pollution is easily caused.

Disclosure of Invention

In view of the above, the application provides a two-component pouring sealant, a preparation method and application thereof, wherein the two-component pouring sealant is stable in the use process after pouring electronic components, and the contained PPC can be degraded into small molecular compounds in a weakly alkaline environment and can be degraded through composting, so that the technical problems that the electronic components in the prior art cannot be maintained and recovered after pouring the electronic components are easily polluted are solved.

The first aspect of the application provides a two-component pouring sealant, which comprises a component A and a component B;

the component A comprises polypropylene carbonate polyol, diisocyanate, an organic metal catalyst and an anti-aging agent;

the component B comprises a chain extension crosslinking agent, a catalyst, a defoaming agent and an ultraviolet absorber.

Preferably, the polypropylene carbonate polyol comprises 2 or more PPCs having a molecular weight of 500 to 3000 g/mol.

PPC is referred to herein as a polypropylene carbonate polyol.

Preferably, the A component comprises, in parts by mass:

100 parts of polypropylene carbonate polyol;

20-60 parts of diisocyanate;

0.01 to 0.1 part of organic metal catalyst;

0.1-5 parts of anti-aging agent;

the component B comprises the following components:

1-15 parts of chain extension cross-linking agent;

0.01 to 0.1 portion of cross-linking agent;

0.1-1 part of defoaming agent;

0.1 to 1 part of ultraviolet absorber.

Preferably, the diisocyanate comprises one or more of toluene diisocyanate, diphenylmethane diisocyanate, liquefied diphenylmethane diisocyanate, polymeric isocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and hydrogenated diphenylmethane diisocyanate.

Preferably, the organometallic catalyst comprises one or more of stannous octoate, stannous iso-octoate, dibutyltin dilaurate and organobismuth.

Preferably, the anti-aging agent comprises 2, 6-di-t-butyl-4-methylphenol and/or pentaerythritol tetrakis [ beta- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate ].

Preferably, the chain-extending crosslinking agent comprises one or more of ethylene glycol, butanediol, diethylene glycol, dipropylene glycol, 1, 6-hexanediol, 1, 3-propanediol, 1, 2-propanediol, trimethylolpropane, 1, 4-hydroxymethyl cyclohexane, trimethylpentanediol, di-n-butylamine, ethylenediamine, trimethylhexamethylenediamine, tetraethylenepentamine, diethylenetriamine and isophorone diamine.

Preferably, the crosslinking agent comprises trimethylolpropane.

Preferably, the ultraviolet absorber comprises 2-hydroxy-4-n-octoxybenzophenone and/or 2-hydroxy-4-methoxybenzophenone.

Preferably, the defoamer comprises a silicone-based defoamer.

The second aspect of the application provides a preparation method of the two-component pouring sealant, wherein the preparation method of the component A comprises the following steps: reacting the dehydrated polypropylene carbonate polyol with organic metal catalyst, diisocyanate and an anti-aging agent at 75-85 ℃ in nitrogen atmosphere to obtain a component A;

the preparation method of the component B comprises the following steps: and (3) reacting the chain extension crosslinking agent, the defoaming agent and the ultraviolet absorber at 75-85 ℃ to obtain the component B.

The third aspect of the application provides application of the pouring sealant in the field of electronic components.

The pouring sealant provided by the application has the characteristics of easy removal and easy degradation, so that the maintenance and recovery of electronic components can be realized, and the pouring sealant can be widely applied to the fields of various electronic components.

In summary, the application provides a two-component pouring sealant, and a preparation method and application thereof; the double-component pouring sealant comprises a component A and a component B, wherein the component A comprises polypropylene carbonate polyol, diisocyanate, an organic metal catalyst and an anti-aging agent, and the component B comprises a chain extension crosslinking agent, a catalyst, a defoaming agent and an ultraviolet absorber; when the double-component pouring sealant is used, firstly, the component A and the component B are mixed and stirred according to a certain proportion, then, the components are quickly poured into the electronic component, and finally, the electronic component is cured to realize the pouring of the electronic component, when the electronic component has a local problem, the pouring sealant is soaked in weak alkaline solution such as ethanolamine and the like, water molecules in the solution can be adsorbed onto a molecular chain of the pouring sealant and undergo hydrolysis reaction with ester groups on the molecular chain of the pouring sealant to generate a short molecular chain, the short molecular chain is continuously hydrolyzed into a small molecular chain, so that the double-component pouring sealant loses strength and can be removed, the maintenance and the recovery of the electronic component are realized, and the removed pouring sealant can be degraded through compost without causing environmental pollution.

Drawings

In order to more clearly illustrate the embodiments of the invention or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the invention, and that other drawings can be obtained from these drawings without inventive faculty for a person skilled in the art.

Fig. 1 is a degradation schematic diagram of a two-component pouring sealant according to an embodiment of the present application.

Detailed Description

The application provides a two-component pouring sealant, a preparation method and application thereof, wherein the two-component pouring sealant is stable in the use process after pouring electronic components, the contained PPC can be degraded into micromolecular compounds in a weak alkaline environment, and after the pouring sealant is abandoned, the pouring sealant can be degraded through composting, so that the technical problems that the electronic components in the prior art cannot be maintained and recovered after pouring the electronic components are easily polluted are solved.

The following description of the technical solutions in the embodiments of the present application will be clear and complete, and it is obvious that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

Among them, the reagents and raw materials used in the following examples are all commercially available or homemade.

Example 1

The embodiment 1 of the application provides a preparation method of a first two-component pouring sealant, which comprises the steps of preparing an A component and preparing a B component.

(1) Preparation of component A

According to the mass parts, 60 parts of polypropylene carbonate with the molecular weight of 1000g/mol and 40 parts of polypropylene carbonate with the molecular weight of 2000g/mol are dehydrated in vacuum for 2-3 hours at the temperature of 110-120 ℃, then cooled to 60-70 ℃, 0.08 part of organic metal catalyst stannous octoate is added, 25 parts of isophorone diisocyanate is added and gradually heated to 75-85 ℃ for reaction within 30min, nitrogen protection is introduced in the reaction process, the NCO% value is tested, when the NCO% value reaches a set value, the reaction is stopped, and an anti-aging agent 2, 6-di-tert-butyl-4-methylphenol is added, so that the component A is obtained, and the set value is within the range of 5% -15%.

(2) Preparation of component B

3 parts of chain extender butanediol, 0.1 part of crosslinking agent trimethylolpropane and a reaction kettle are added into the reaction kettle to be stirred and mixed, preheated to 50-80 ℃, 0.1 part of organosilicon defoamer and 0.2 part of ultraviolet absorbent catalyst 2-hydroxy-4-n-octoxybenzophenone are added into the reaction kettle to be uniformly stirred and defoamed, and the component B is obtained.

Example 2

The embodiment 2 of the application provides a preparation method of a second two-component pouring sealant, which comprises the steps of preparing an A component and preparing a B component.

The difference with example 1 is that the preparation raw materials of the component A and the component B are as follows:

example 3

The embodiment 3 of the application provides a preparation method of a third two-component pouring sealant, which comprises the steps of preparing an A component and preparing a B component.

The difference from example 1 is that the preparation raw materials of the A component and the B component are:

raw materials	A component
		Polypropylene carbonate polyol (mn=2000)	60
Polypropylene carbonate polyol (mn=3000)	40
		Toluene diisocyanate (MDI)	20
Catalyst (stannous octoate)	0.08
		Anti-aging agent (2, 6-di-tert-butyl-4-methylphenol)	0.1

		Raw materials	Component B
Chain extender (butanediol)	3
		Crosslinking agent (trihydroxy)Methyl propane)	0.5
Defoaming agent BYK-A530	0.1
		Ultraviolet absorber (2-hydroxy-4-n-octoxybenzophenone)	0.2
The mass mixing ratio of the component A and the component B	100:15

Example 4

The embodiment 4 of the application provides a preparation method of a fourth two-component pouring sealant, which comprises the steps of preparing an A component and preparing a B component.

raw materials	A component
		Polypropylene carbonate polyol (mn=2000)	60
Polypropylene carbonate polyol (mn=3000)	40
		Toluene diisocyanate (MDI)	20
Catalyst (stannous octoate)	0.08
		Anti-aging agent (2, 6-di-tert-butyl-4-methylphenol)	0.15

		Raw materials	Component B
Chain extender (dipropylene glycol)	3
		Crosslinking agent (trimethylolpropane)	0.5
Defoaming agent BYK-392	0.1
		Ultraviolet absorbent (2-hydroxy-4-methoxybenzophenone)	0.2
The mass mixing ratio of the component A and the component B	100:10

Comparative example 1

Comparative example 1 of the present application provides a fifth method for preparing a two-component pouring sealant, comprising the preparation of component a and the preparation of component B.

comparative example 2

Comparative example 2 of the present application provides a sixth method for preparing a two-component pouring sealant, comprising the preparation of component a and the preparation of component B.

raw materials	A component
		Polytetrahydrofuran (mn=3000)	40
Isophorone diisocyanate (IPDI)	25
		Catalyst (stannous octoate)	0.08
Anti-aging agent (2, 6-di-tert-butyl-4-methylphenol)	0.15

Raw materials	Component B
		Chain extender (dipropylene glycol)	3
Crosslinking agent (trimethylolpropane)	0.5
		Defoaming agent BYK-088	0.1
Ultraviolet absorbent (2-hydroxy-4-methoxybenzophenone)	0.2
		The mass mixing ratio of the component A and the component B	100:12

Example 5

This example 5 is a performance test of the pouring sealant prepared in examples 1-2 and comparative examples 1-2, and the test procedure includes: the pouring sealant prepared in the examples 1-2 and the comparative examples 1-2 is firstly mixed and stirred for 3min according to the mass ratio, then is quickly poured into a mould preheated at 60 ℃, is sequentially cured at 60 ℃ for 24h and at 100 ℃ for 24h to obtain a spline, and then the hardness, the strength and the degradation removal performance of the spline are sequentially tested, and the results are shown in the table 1:

TABLE 1

In Table 1, the degradation agents were diethanolamine and triethanolamine, and the solvents were tetrahydrofuran, ethyl acetate, butyl acetate, and the like.

As can be seen from table 1, compared with the pouring sealant prepared in comparative example 1, the pouring sealant provided in the embodiment of the present application can be degraded in a mixed solvent of diethanolamine and tetrahydrofuran, because the pouring sealant is soaked in a weak alkaline solution such as ethanolamine, water molecules in the solution can be adsorbed onto a molecular chain of the pouring sealant, and a hydrolysis reaction occurs between the water molecules and ester groups on the molecular chain of the pouring sealant, so as to generate a short molecular chain, and the short molecular chain is continuously hydrolyzed into a small molecular chain, thereby the strength of the two-component pouring sealant is lost, and the two-component pouring sealant can be removed; the degradation principle is shown in figure 1.

The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.

Claims

1. The double-component pouring sealant is characterized by comprising a component A and a component B;

the component A consists of polypropylene carbonate polyol, diisocyanate, an organic metal catalyst and an anti-aging agent;

the component B consists of a chain extension crosslinking agent, a catalyst, a defoaming agent and an ultraviolet absorber;

the polypropylene carbonate polyol comprises 2 or more than 2 PPCs with molecular weights of 500-3000 g/mol;

the component A consists of the following components in parts by mass:

100 parts of polypropylene carbonate polyol;

20-60 parts of diisocyanate;

0.01-0.1 parts of an organic metal catalyst;

0.1-5 parts of an anti-aging agent;

the component B consists of the following components:

1-15 parts of chain extension cross-linking agent;

0.01-0.1 part of cross-linking agent;

0.1-1 part of defoaming agent;

0.1-1 parts of ultraviolet absorber.

2. The two-component pouring sealant according to claim 1, wherein the diisocyanate comprises one or more of toluene diisocyanate, diphenylmethane diisocyanate, liquefied diphenylmethane diisocyanate, polymeric isocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and hydrogenated diphenylmethane diisocyanate.

3. The two-component pouring sealant according to claim 1, wherein the organometallic catalyst comprises one or more of stannous octoate, stannous iso-octoate, dibutyltin dilaurate, and organobismuth.

4. The two-component pouring sealant according to claim 1, wherein the anti-aging agent comprises 2, 6-di-t-butyl-4-methylphenol and/or pentaerythritol tetrakis [ beta- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate ].

5. The two-component pouring sealant according to claim 1, wherein the chain-extending cross-linking agent comprises one or more of ethylene glycol, butanediol, diethylene glycol, dipropylene glycol, 1, 6-hexanediol, 1, 3-propanediol, 1, 2-propanediol, trimethylolpropane, 1, 4-hydroxymethylcyclohexane, trimethylpentanediol, di-n-butylamine, ethylenediamine, trimethylhexamethylenediamine, tetraethylenepentamine, diethylenetriamine and isophorone diamine.

6. The two-component pouring sealant according to claim 1, wherein the ultraviolet absorber comprises 2-hydroxy-4-n-octoxybenzophenone and/or 2-hydroxy-4-methoxybenzophenone.

7. The method for preparing the two-component pouring sealant according to any one of claims 1 to 6, wherein the method for preparing the component A comprises the following steps: reacting the dehydrated polypropylene carbonate polyol with organic metal catalyst, diisocyanate and an anti-aging agent at 75-85 ℃ in a nitrogen atmosphere to obtain a component A;

8. The application of the two-component pouring sealant prepared by the preparation method of any one of claims 1-6 or the preparation method of claim 7 in the field of electronic components.