Novel slow-gelation fast-curing polyurethane material

Abstract

The invention relates to a novel slow-gelation fast-curing polyurethane material, which is prepared from the following components in parts by mass: 52 to 58 parts of aromatic diisocyanate, 85 to 100 parts of polyether polyol, 0.1 to 0.3 part of composite catalyst and 0.3 to 0.6 part of cross-linking agent, the composite catalyst is formed by compounding a tertiary amine catalyst and an organic tin catalyst according to a mass ratio of 7: 5. According to the invention, the catalyst compounded by the tertiary amine catalyst and the organic tin catalyst in a specific proportion is introduced in the polyurethane synthesis process, so that the reaction has the advantage of controllable catalytic effect. The activity at the early stage of reaction is low, so that the gelation time is effectively prolonged, a mold can be fully filled with feed liquid, the injection molding period of a large and complex panoramic sunroof is well met, and the yield is improved; meanwhile, the curing speed in the later reaction period is high, and the production efficiency of products can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane materials, in particular to a novel slow-gelling and fast-curing polyurethane material. Background Art

[0002] With the rapid development of the automobile manufacturing industry, customers have higher and higher requirements for the appearance, performance, and comfort of automobiles. At present, the sunroof, an important component of automobiles, is basically developing towards large-sized, complex panoramic sunroof assembly products and new energy vehicle panoramic skylight assembly products, and its molding process is PU injection molding edging. However, due to the fast reaction speed of existing injection molding PU materials, its gel time can basically only reach 5-7s, which cannot meet the filling cycle of large products. There are often problems such as product shortage or glass breakage caused by injection molding pressure, which affects the production quality of large products; at the same time, its complete curing time takes more than 40s, which affects the production efficiency of the product.

[0003] In view of this, the present invention is proposed. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a novel slow-gelling and fast-curing polyurethane material.

[0005] The technical solution adopted by the present invention is:

[0006] The present invention provides a novel slow-gelling fast-curing polyurethane material, comprising:

[0007] 52-58 parts of aromatic diisocyanate, 85-100 parts of polyether polyol, 0.1-0.3 parts of composite catalyst, 0.3-0.6 parts of cross-linking agent;

[0008] The composite catalyst is formed by compounding a tertiary amine catalyst and an organic tin catalyst in a mass ratio of 7:5.

[0009] The invention proposes a novel slow-gelling and fast-curing polyurethane material, which has the advantage of controllable catalytic effect by introducing a catalyst compounded with a tertiary amine catalyst and an organic tin catalyst in a specific ratio during the polyurethane synthesis process. The low activity in the early stage of the reaction effectively prolongs the gel time, allowing the liquid to fully fill the mold, well meeting the injection molding cycle of large and complex panoramic sunroofs and improving the yield rate; at the same time, the fast curing speed in the later stage of the reaction can improve the production efficiency of the product.

[0010] Preferably, the tertiary amine catalyst is N,N-dimethylcyclohexylamine.

[0011] Preferably, the organotin catalyst is dimethyl tin glycolate.

[0012] Preferably, the aromatic diisocyanate is diphenylmethane diisocyanate.

[0013] Preferably, the polyether polyol is polyoxypropylene polyether polyol or polytetramethylene glycol polyether polyol.

[0014] Preferably, the cross-linking agent is an amine cross-linking agent or an alcohol cross-linking agent.

[0015] Preferably, it also includes, by mass:

[0016] 1-3 parts of antioxidant, 0.3-0.5 parts of flame retardant, 1-3 parts of light stabilizer, 0.5-1 parts of colorant. DETAILED DESCRIPTION

[0017] In order to better understand the above technical scheme, exemplary embodiments of the present invention will be described in more detail below. It should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a clearer and more thorough understanding of the present invention, and to be able to fully convey the scope of the present invention to those skilled in the art.

[0018] The embodiment of the present invention provides a novel slow-gelling fast-curing polyurethane material, comprising:

[0019] 52-58 parts of aromatic diisocyanate, 85-100 parts of polyether polyol, 0.1-0.3 parts of composite catalyst, 0.3-0.6 parts of cross-linking agent;

[0020] The composite catalyst is formed by mixing a tertiary amine catalyst and an organic tin catalyst in a mass ratio of 7:5.

[0021] The inventor found that when the mass ratio of the tertiary amine catalyst and the organotin catalyst in the composite catalyst is 7:5, the gel speed and the curing speed of the reaction can be coordinated without adjusting or optimizing the overall formula and process of the polyurethane material, so as to achieve the effect of long gel time in the early stage of the material mixing reaction and fast curing speed in the later stage, which well meets the requirements of large and complex products and adapts to the process of the glass hemming industrial production line. If the mass ratio of the tertiary amine catalyst and the organotin catalyst is greater than 7:5, that is, when the amount of the tertiary amine catalyst is too much, although the curing speed in the later stage of the reaction can be improved, the gel time of the reaction after the material mixing will be greatly shortened, and the operation time is too short, which is not conducive to the production quality of the product; if the mass ratio of the tertiary amine catalyst and the organotin catalyst is less than 7:5, that is, when the amount of the organotin catalyst is too much, although the gel time in the early stage of the reaction can be extended, the curing speed in the later stage of the material mixing reaction will be greatly reduced, which is not conducive to the production efficiency of the product. Therefore, the mass ratio of the tertiary amine catalyst and the organotin catalyst is 7:5 as the best.

[0022] In a preferred embodiment of the present invention, the tertiary amine catalyst is N,N-dimethylcyclohexylamine.

[0023] In a preferred embodiment of the present invention, the organotin catalyst is dimethyltin glycolate.

[0024] In the present invention, N,N-dimethylcyclohexylamine is selected as a tertiary amine catalyst and dimethyltin glycolate is selected as an organic tin catalyst. They are compounded in a specific ratio and applied to the injection molding and edge wrapping process of polyurethane materials. The gel time of the mixed liquid in the early stage of the reaction can reach more than 10 seconds, and the curing speed in the later stage is fast, and the coagulation time of the whole reaction is as low as 30 seconds.

[0025] In a preferred embodiment of the present invention, the aromatic diisocyanate is diphenylmethane diisocyanate. In the present invention, for example, diphenylmethane diisocyanate may be 4,4-diphenylmethane diisocyanate, etc., without particular limitation.

[0026] In a preferred embodiment of the present invention, the polyether polyol is polyoxypropylene polyether polyol or polytetrahydrofuran polyether polyol. In the present invention, the functionality of the polyether polyol is preferably 2-4 and the average molecular weight is 1000-2000.

[0027] In a preferred embodiment of the present invention, the crosslinking agent is an amine crosslinking agent or an alcohol crosslinking agent. In the present invention, for example, the amine crosslinking agent can be any one of 3,3'-dichloro-4,4-diaminodiphenylmethane, diethyltoluenediamine, 3,5-dimethylthiotoluenediamine, etc., without special restrictions; the alcohol crosslinking agent can be any one of 1,4-butanediol, 1,6-hexanediol, ethylene glycol, 1,3-propylene glycol, without special restrictions.

[0028] In a preferred embodiment of the present invention, it also includes, by mass:

[0029] 1-3 parts of antioxidant, 0.3-0.5 parts of flame retardant, 1-3 parts of light stabilizer, 0.5-1 parts of colorant.

[0030] In the present invention, for example, the antioxidant may be antioxidant 1010, etc., the flame retardant may be tris(2-chloroethyl)phosphate, etc., and the colorant may be carbon black, etc., without particular limitation.

[0031] In addition, the present invention has no particular limitation on the preparation method of the novel slow-gelling, fast-curing polyurethane material. For example, the method may be as follows: aromatic diisocyanate is used as component B, and the remaining raw materials are used as component A, which are placed in respective raw material tanks of respective molding machines, and the raw material temperature is set to 35-50°C, the injection pressure is set to 140-160 bar, and the mold temperature is set to 90-120°C. After the materials are pressed and mixed, they are injected into the mold for reaction curing and molding.

[0032] Example 1

[0033] A novel slow-gel fast-curing polyurethane material, comprising, by weight:

[0034] 56 parts of 4,4-diphenylmethane diisocyanate, 100 parts of polypropylene glycol, 0.12 parts of composite catalyst, 0.5 parts of 1,4-butanediol, 1 part of antioxidant 1010, 0.4 parts of tris(2-chloroethyl)phosphate, 1 part of light stabilizer, and 0.6 parts of carbon black;

[0035] The composite catalyst is formed by mixing N,N-dimethylcyclohexylamine and dimethyltin glycolate in a mass ratio of 7:5.

[0036] Comparative Examples 1-7

[0037] The difference between Comparative Examples 1-7 and Example 1 is that the mass ratios of N,N-dimethylcyclohexylamine and dimethyltin glycolate in the composite catalyst are different, namely 7:2, 7:3, 7:4, 7:6, 7:7, 7:8, and 7:9, respectively. The other steps remain unchanged.

[0038] Comparative Example 8

[0039] The difference between this comparative example and Example 1 is that the type of composite catalyst is different, and triethylenediamine and dimethyltin dilaurate are compounded instead. The other steps remain unchanged.

[0040] Comparative Example 9

[0041] The difference between this comparative example and Example 1 is that the type of composite catalyst is different, and triethylenediamine and dioctyltin didodecylthioate are used instead. The other steps remain unchanged.

[0042] The polyurethane materials prepared in Example 1 and Comparative Examples 1-9 were tested for performance, and the results are recorded in Tables 1-3.

[0043] Test method:

[0044] (1) Reaction time: The time required for the mixture to change from a liquid state to a viscous flow state after components A and B are mixed according to the above preparation method.

[0045] (2) Setting time: The time required for the mixture to change from liquid to solid and completely solidify after components A and B are mixed according to the above preparation method.

[0046] (3) Mechanical properties test: Test according to national standards.

[0047] Table 1 Reaction time and coagulation time test results of Example 1 and Comparative Examples 1-7

[0048]

[0049] Table 2 Reaction time and coagulation time test results of Example 1 and Comparative Examples 8-9

[0050] Type of composite catalyst (mass ratio of tertiary amine to organotin = 7:5) Reaction time / s Solidification time / s Example 1 N,N-Dimethylcyclohexylamine and dimethyltin glycolate 10.5 30 Comparative Example 8 Triethylenediamine and dimethyltin dilaurate 8 35 Comparative Example 9 Triethylenediamine and dioctyltin didodecylthioate 7 37

[0051] Table 3 Mechanical properties test results of Example 1

[0052]

[0053]

[0054] As shown in Table 1, when the mass ratio of N, N-dimethylcyclohexylamine and dimethyltin glycolate in the composite catalyst is 7:5, the early reaction time of the polyurethane material of Example 1 of the present invention can reach more than 10s, and the gel time is slightly extended on this basis, which can be about 11s, and the complete solidification time only takes 30s, which is much lower than the 40s of the prior art, and can meet the production process requirements of large-scale products. Compared with Comparative Examples 1-7, the polyurethane materials prepared by using catalysts compounded with other mass ratios cannot coordinate the gel time in the early stage of the reaction and the curing speed in the later stage of the reaction. As can be seen from Table 2, compared with Comparative Examples 8 and Comparative Examples 9, the polyurethane materials prepared by using catalysts compounded with other types of tertiary amine catalysts and organic tin catalysts can only reach 7-8s in the early reaction time of the polyurethane material, and the operating time is less, and the complete solidification time takes at least 35-37s, which is closer to the 40s of the prior art, and there is no obvious improvement, and it still cannot meet the production process requirements of large-size products. It can be seen from Table 3 that the novel slow-gelling fast-curing polyurethane material of the present invention also has good mechanical properties.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A novel slow-gelling fast-curing polyurethane material, comprising, by mass: 52-58 parts of aromatic diisocyanate, 85-100 parts of polyether polyol, 0.1-0.3 parts of composite catalyst, 0.3-0.6 parts of cross-linking agent; The composite catalyst is formed by compounding a tertiary amine catalyst and an organic tin catalyst in a mass ratio of 7:

5.

2. The novel slow gel fast curing polyurethane material according to claim 1, characterized in that: The tertiary amine catalyst is N,N-dimethylcyclohexylamine.

3. The novel slow gel fast curing polyurethane material according to claim 1, characterized in that: The organotin catalyst is dimethyl tin glycolate.

4. The novel slow gel fast curing polyurethane material according to claim 1, characterized in that: The aromatic diisocyanate is diphenylmethane diisocyanate.

5. The novel slow gel fast curing polyurethane material according to claim 1, characterized in that: The polyether polyol is polyoxypropylene polyether polyol or polytetramethylene ether polyol.

6. The novel slow gel fast curing polyurethane material according to claim 1, characterized in that: The cross-linking agent is an amine cross-linking agent or an alcohol cross-linking agent.

7. The novel slow gel fast curing polyurethane material according to claim 1, characterized in that: Also included by mass: 1-3 parts of antioxidant, 0.3-0.5 parts of flame retardant, 1-3 parts of light stabilizer, 0.5-1 parts of colorant.

Images