Light colored modified isocyanate mixture and preparation method thereof

Abstract

Disclosed is a light colored modified isocyanate mixture and a preparation method thereof. The method comprises the following steps: a) reacting isocyanate groups of a raw material isocyanate under the action of a phospholenecatalyst, and finally obtaining a modified isocyanate reaction solution containing carbodiimide and/or uretonimine derivatives; and b) adding a compounded terminator of a halosilane organic and a sulfonic anhydride to the reaction solution obtained in step a so as to terminate the reaction of carbodiimidization. The modified isocyanate prepared by the method has the characteristics of a liquid state at room temperature, being stable in storage at room temperature and high temperature, and low color number.

Claims

1. A preparation method of a light colored modified isocyanate mixture, the method includes the following steps: a) subjecting the isocyanate group of a raw material isocyanate to carbodiimidization under the action of a phosphorus heterocyclic catalyst to obtain a reaction solution of modified isocyanate containing carbodiimide and/or uretonimine derivatives; b) adding a compounded terminator to the reaction solution obtained in step a) to terminate the carbodiimidization; the compounded terminator is a compound of a halosilane organic and a sulfonic anhydride substance.

2. The preparation method according to claim 1, wherein, the reaction of step a) is carried out at a temperature of 40° C.-210° C.

3. The preparation method according to claim 1, wherein, the halosilane organic has a chemical formula of the following formula (I):
R.sub.1X.sub.3Si or R.sub.1R.sub.2X.sub.2Si or R.sub.1R.sub.2R.sub.3X.sub.1Si   (I) in the molecular formula (I), R.sub.1, R.sub.2 and R.sub.3 independently represent aliphatic, aromatic, araliphatic, cycloaliphatic groups optionally containing heteroatoms, wherein R.sub.1, R.sub.2 and R.sub.3 can be the same or different; and two groups of R.sub.1, R.sub.2 and R.sub.3 can be connected to each other to form a ring structure; X represents the halogen element selected from the group consisting of fluorine, chlorine, bromine and iodine.

4. The preparation method according to claim 1, wherein, the sulfonic anhydride substance has the following structural formula (II): ##STR00002## in the structural formula (II), R.sub.4 and R.sub.5 independently represent aliphatic, aromatic, araliphatic, or cycloaliphatic groups optionally contain heteroatoms and/or other functional groups, wherein R.sub.4 and R.sub.5 can be the same or different, the two groups R.sub.4 and R.sub.5 are optionally connected to each other to form a ring structure.

5. The preparation method according to claim 1, wherein, the compounded terminator is a compound of diphenyldifluorosilane and p-toluenesulfonic anhydride.

6. The preparation method according to claim 1, wherein, the temperature condition of adding the compounded terminator to terminate the carbodiimidation of step b) is 40-70° C.

7. The preparation method according to claim 1, wherein, the amount of compounded terminator is based on the weight of the raw material isocyanate, the amount of halosilane organic is 50-2000 ppm; the amount of sulfonic anhydride substance is 10-200 ppm.

8. The preparation method according to claim 1, wherein, the catalyst used for preparing the isocyanate containing carbodiimide and/or uretonimine derivatives is a phospholene catalyst and/or a phospholene oxide, the amount of the catalyst is 0.1-10 ppm, relative to the weight of the raw material isocyanate.

9. The preparation method according to claim 1, wherein, the raw material isocyanate is one or more selected from the group consisting of aromatic, araliphatic, aliphatic, and cycloaliphatic diisocyanates.

10. The preparation method according to claim 1, wherein, when the reaction time of the carbodiimidation reaches 10 min-24 h, the compounded terminator is added to terminate the reaction.

11. The preparation method according to claim 3, wherein, in the molecular formula (I), R.sub.1, R.sub.2 and R.sub.3 independently represent C1-C10 hydrocarbyl, C6-C15 aromatic, C7-C15 araliphatic, or C3-C12 cycloaliphatic groups optionally containing heteroatoms.

12. The preparation method according to claim 11, wherein in the molecular formula (I), R.sub.1, R.sub.2 and R.sub.3 independently represent phenyl, tolyl, ethylphenyl, phenmethyl or phenyethyl optionally containing heteroatoms.

13. The preparation method according to claim 3, wherein, the halosilane organic is selected from the group consisting of diphenyldifluorosilane, diphenyldichlorosilane, tritylfluorosilane, tert-butyltrichlorosilane and combinations thereof.

14. The preparation method according to claim 4, wherein, in the structural formula (II), R.sub.4 and R.sub.5 independently represent C1-C10 hydrocarbyl, C6-C15 aromatic, C7-C15 araliphatic, or C3-C12 cycloaliphatic groups optionally contain heteroatoms and/or other functional groups.

15. The preparation method according to claim 14, wherein, in the structural formula (II), R.sub.4 and R.sub.5 independently represent phenyl, tolyl, ethylphenyl, phenmethyl, phenethyl, cyclopropyl, cyclobutyl, cyclohexyl or cyclopentyl optionally containing heteroatoms and/or other functional groups.

16. The preparation method according to claim 4, wherein, the sulfonic anhydride substance is selected from the group consisting of p-toluenesulfonic anhydride, methanesulfonic anhydride, ethylsulfonic anhydride, trifluoromethanesulfonic anhydride and combinations thereof.

17. The preparation method according to claim 7, wherein, the amount of compounded terminator is based on the weight of the raw material isocyanate, the amount of halosilane organic is 100-600 ppm; the amount of sulfonic anhydride substance is 10-100 ppm.

18. The preparation method according to claim 7, wherein, the compounding mass ratio of the halosilane organic and the sulfonic anhydride substance is 2-6:1.

19. The preparation method according to claim 8, wherein, the amount of the catalyst is 0.2-2 ppm relative to the weight of the raw material isocyanate.

20. The preparation method according to claim 9, wherein, the raw material isocyanate is diphenylmethane diisocyanate.

Description

EMBODIMENTS

(1) The present invention is further illustrated by the following examples, but the scope of the present invention is not limited to the following examples.

(2) The raw material: diphenylmethane diisocyanate, wherein the diphenylmethane diisocyanate contains 97-100 wt % 4,4-isomer, 0-1 wt % 2,2-isomer, and 0.5-1.8 wt % 2,4-isomer, the content of NCO is 33.6 wt %.

(3) The catalyst is: a solution of 1-methyl-3-methyl-3-phospholene-1-oxide or 1-phenyl-3-methyl-3-phospholene-1-oxide, using dichloromethane as the solvent, and the concentration of catalyst was 1% relative to the mass of the solvent dichloromethane; both the catalyst and the solvent were purchased and available from Sinopharm.

(4) Diphenyldifluorosilane, purity 96%, color number 10 #, from Suzhou Yake Technology Co., Ltd.

(5) Tritylfluorosilane, purity 96%, available from Sinopharm.

(6) P-toluenesulfonic anhydride, purity 95%, available from Sinopharm.

(7) Trifluoromethanesulfonic anhydride, purity 98%, available from Sinopharm.

(8) Trimethylsilyltrifluoromethanesulfonate, purity 95%, available from Sinopharm.

(9) Dibutyl phosphate, purity 98%, available from Sinopharm.

Comparative Example 1

(10) 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of phospholene (i.e., a solution of 1-phenyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.5 ppm (0.025 g) was added, after mixing, the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 200 g diphenylmethane diisocyanate was further added, and 200 ppm (0.1 g) of terminator diphenyldifluorosilane was added, the temperature was rapidly reduced to 60° C., after stirring the mixture for 30 minutes, 200 g diphenylmethane diisocyanate was further added again, then the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. The test results of the final product are shown in tables 1-2.

(11) This comparative example can also be carried out according to the following steps: 500 g diphenylmethane diisocyanate was heated to about 50° C. while stirring under the protection of N.sub.2, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene with a catalyst amount of 0.025 g was added, after mixing the mixture was quickly heated to 200° C., and 400 g diphenylmethane diisocyanate was further added after reacting for 90 minutes, and after the temperature was rapidly cooled to 60° C., 0.1 g terminator diphenyldifluorosilane was added, and the mixture was stirred for 30 minutes and then heated to 70-80° C., and stirred for 120 minutes to obtain the final product. There is no significant change in the properties of this product relative to the properties of the product prepared according to the aforementioned steps.

Example 1

(12) 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene (i.e., a solution of 1-phenyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.5 ppm (0.025 g) was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 200 g diphenylmethane diisocyanate was further added, then 200 ppm (0.1 g) of terminator diphenyldifluorosilane and 50 ppm (0.025 g) of terminator p-toluenesulfonic anhydride were added, the temperature was rapidly cooled to 60° C., after stirring the mixture for 30 minutes, 200 g diphenylmethane diisocyanate was further added again, and the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. The test results of the final product are shown in tables 1-2.

(13) This example can also be performed according to the following steps:

(14) 500 g of diphenylmethane diisocyanate was heated to about 50° C. while stirring under the protection of N.sub.2, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene with a catalyst amount of 0.025 g was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 400 g diphenylmethane diisocyanate was further added, the temperature was rapidly cooled to 60° C., 0.1 g terminator diphenyldifluorosilane and 0.025 g terminator p-toluenesulfonic anhydride were added, and the mixture was stirred for 30 minutes and then heated to 70-80° C., and stirred for 120 minutes to obtain the final product. There is no significant change in the properties of this product relative to the properties of the product prepared according to the aforementioned steps.

Example 2

(15) 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene (as a solution of 1-phenyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.5 ppm (0.025 g) was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 200 g diphenylmethane diisocyanate was further added, then 200 ppm (0.1 g) of terminator diphenyldichlorosilane and 50 ppm (0.025 g) of terminator trifluoromethylsulfonic anhydride were added, the temperature was rapidly cooled to 60° C., after stirring the mixture for 30 minutes, then 200 g diphenylmethane diisocyanate was further added again, and the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. The test results of the final product are shown in tables 1-2.

(16) This example can also be performed according to the following steps:

(17) 500 g diphenylmethane diisocyanate was heated to about 50° C. while stirring under the protection of N.sub.2, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene with a catalyst amount of 0.025 g was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 400 g diphenylmethane diisocyanate was further added, the temperature was rapidly cooled to 60° C., 0.1 g terminator diphenyldichlorosilane and 0.025 g terminator trifluoromethylsulfonic anhydride were added, and the mixture was stirred for 30 minutes and then heated to 70-80° C., and stirred for 120 minutes to obtain the final product. There is no significant change in the properties of this product relative to the properties of the product prepared according to the aforementioned steps.

Example 3

(18) 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-methyl-3-methyl-3-phospholene-1-oxide (i.e., a solution of 1-methyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 1 ppm (0.05 g) was added, after mixing the mixture was quickly heated to 120° C., and after reacting for 200 minutes, 200 g diphenylmethane diisocyanate was further added, then 200 ppm (0.1 g) of terminator tritylfluorosilane and 50 ppm (0.025 g) of terminator p-toluenesulfonic anhydride were added, the temperature was rapidly cooled to 60° C., after stirring the mixture for 30 minutes, then 200 g diphenylmethane diisocyanate was further added again, and the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. The test results of the final product are shown in tables 1-2.

(19) This example can also be performed according to the following steps: 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene-1-oxide (i.e., a solution of 1-phenyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.05 g was added, after mixing the mixture was quickly heated to 120° C., and after reacting for 200 minutes, 400 g diphenylmethane diisocyanate was further added, the temperature was rapidly cooled to 60° C., 0.1 g terminator tritylfluorosilane and 0.025 g terminator p-toluenesulfonic anhydride were added, after stirring the mixture for 30 minutes, the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. There is no significant change in the properties of this product relative to the properties of the product prepared according to the aforementioned steps.

Example 4

(20) 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-methyl-3-methyl-3-phospholene-1-oxide (as a solution of 1-methyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.5 ppm (0.025 g) was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 200 g diphenylmethane diisocyanate was further added, then 100 ppm (0.05 g) of terminator diphenyldifluorosilane and 20 ppm (0.01 g) of terminator trifluoromethylsulfonic anhydride were added, the temperature was rapidly cooled to 60° C., after stirring the mixture for 30 minutes, then 200 g diphenylmethane diisocyanate was further added again, then the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. The test results of the final product are shown in tables 1-2.

(21) This example can also be performed according to the following steps: 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene-1-oxide (a solution of 1-phenyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.025 g was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 400 g diphenylmethane diisocyanate was further added, the temperature was rapidly cooled to 60° C., 0.05 g terminator diphenyldifluorosilane and 0.01 g terminator trifluoromethylsulfonic anhydride were added, after stirring the mixture for 30 minutes, the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. There is no significant change in the properties of this product relative to the properties of the product prepared according to the aforementioned steps.

Comparative Example 2

(22) 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene (i.e., a solution of 1-phenyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.5 ppm (0.025 g) was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 200 g diphenylmethane diisocyanate was further added, then 10 ppm (0.025 g) of terminator trimethylsilyl trifluoromethanesulfonate was added, the temperature was rapidly cooled to 60° C., after stirring the mixture for 30 minutes, then 200 g diphenylmethane diisocyanate was further added again, then the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. The test results of the final product are shown in tables 1-2.

(23) This comparative example can also be performed according to the following steps: 500 g diphenylmethane diisocyanate was heated to about 50° C. while stirring under the protection of N.sub.2, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene with a catalyst amount of 0.025 g was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 400 g diphenylmethane diisocyanate was further added, the temperature was rapidly cooled to 60° C., 0.025 g of terminator trimethylsilyl trifluoromethanesulfonate was added, and the mixture was stirred for 30 minutes and then heated to 70-80° C., and stirred for 120 minutes to obtain the final product. There is no significant change in the properties of this product relative to the properties of the product prepared according to the aforementioned steps.

Comparative Example 3

(24) 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene (i.e., a solution of 1-phenyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.5 ppm 0.025 g) was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 200 g diphenylmethane diisocyanate was further added, then 10 ppm (0.005 g) of terminator trimethylsilyl trifluoromethanesulfonate compounding with 200 ppm (0.1 g) of dibutyl phosphate was added, the temperature was rapidly cooled to 60° C., after stirring the mixture for 30 minutes, then 200 g diphenylmethane diisocyanate was further added again, then the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. The test results of the final product are shown in tables 1-2.

(25) This comparative example can also be performed according to the following steps: 500 g diphenylmethane diisocyanate was heated to about 50° C. while stirring under the protection of N.sub.2, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene with a catalyst amount of 0.025 g was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 400 g diphenylmethane diisocyanate was further added, the temperature was rapidly cooled to 60° C., 0.005 g terminator trimethylsilyl trifluoromethanesulfonate compounding with 0.1 g dibutyl phosphate was added, and the mixture was stirred for 30 minutes and then heated to 70-80° C., and stirred for 120 minutes to obtain the final product. There is no significant change in the properties of this product relative to the properties of the product prepared according to the aforementioned steps.

Comparative Example 4

(26) 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene (i.e., a solution of 1-phenyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.5 ppm (0.025 g) was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 200 g diphenylmethane diisocyanate was further added, then 50 ppm (0.025 g) of terminator p-toluenesulfonic anhydride was added, the temperature was rapidly cooled to 60° C., after stirring the mixture for 30 minutes, 200 g diphenylmethane diisocyanate was further added again, then the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. The test results of the final product are shown in tables 1-2.

(27) This comparative example can also be performed according to the following steps: 500 g diphenylmethane diisocyanate was heated to about 50° C. while stirring under the protection of N.sub.2, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene with a catalyst amount of 0.025 g was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 400 g diphenylmethane diisocyanate was further added, the temperature was rapidly cooled to 60° C., 0.025 g terminator p-toluenesulfonic anhydride was added, and the mixture was stirred for 30 minutes and then heated to 70-80° C., and stirred for 120 minutes to obtain the final product. There is no significant change in the properties of this product relative to the properties of the product prepared according to the aforementioned steps.

Comparative Example 5

(28) 500 g diphenylmethane diisocyanate was heated to about 50° C. under the protection of N.sub.2 while stirring, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene (i.e., a solution of 1-phenyl-3-methyl-3-phospholene-1-oxide) with a catalyst amount of 0.5 ppm (0.025 g) was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 200 g diphenylmethane diisocyanate was further added, then 50 ppm (0.025 g) of terminator methyl trifluoromethanesulfonate was added, the temperature was rapidly cooled to 60° C., after stirring the mixture for 30 minutes, 200 g diphenylmethane diisocyanate was further added again, then the temperature was raised to 70-80° C., and stirred for 120 min to obtain the final product. The test results of the final product are shown in tables 1-2.

(29) This comparative example can also be performed according to the following steps: 500 g diphenylmethane diisocyanate was heated to about 50° C. while stirring under the protection of N.sub.2, and a high-efficiency catalyst solution of 1-phenyl-3-methyl-3-phospholene with a catalyst amount of 0.025 g was added, after mixing the mixture was quickly heated to 200° C., and after reacting for 90 minutes, 400 g diphenylmethane diisocyanate was further added, the temperature was rapidly cooled to 60° C., 0.025 g terminator methyl trifluoromethanesulfonate was added, and the mixture was stirred for 30 minutes and then heated to 70-80° C., and stirred for 120 minutes to obtain the final product. There is no significant change in the properties of this product relative to the properties of the product prepared according to the aforementioned steps.

(30) The comparison of each product in storage stability and color number is shown in tables 1-2.

(31) Wherein, the viscosity refers to the national standard GB/T 12009.3-2009 of the People Republic of China, polymethylene polyphenyl isocyanate, determination in the viscosity of the third part.

(32) The determination of NCO refers to the national standard GB/T 12009.4-2016 of the People Republic of China, aromatic isocyanates for the production of polyurethane, determination of the isocyanate content in the fourth part.

(33) The color number is determined by a color number instrument, and the color number instrument model is BYK-LCSIII.

(34) TABLE-US-00001 TABLE 1 Comparison table of each product in storage stability and color number viscosity initial after 8 h amount of viscosity degradation the of the at high terminator product viscosity stored at 30° C. (cp) temperature terminator PPM CP 1 month 2 months 6 months (80° C.) (cp) Comparative diphenyldifluorosilane 200  42 43 46 53 90 Example 1 Example 1 diphenyldifluorosilane/ 200/50 40 41 42 44 45 p-toluenesulfonic anhydride Example 2 diphenyldichlorosilane/ 200/50 41 43 44 47 46 trifluoromethanesulfonic anhydride Example 3 tritylfluorosilane/ 200/50 41 43 45 48 48 p-toluenesulfonic anhydride Example 4 diphenyldifluorosilane/ 100/20 42 43 47 49 48 trifluoromethanesulfonic anhydride Comparative trimethylsilyl 50 43 48 50 63 120 Example 2 trifluoromethanesulfonate Comparative trimethylsilyl  10/200 41 42 45 51 105 Example 3 trifluoromethanesulfonate/ dibutyl phosphate Comparative p-toluenesulfonic anhydride 50 43 52 73 112 180 Example 4 Comparative methyl 50 41 57 83 140 230 Example 5 trifluoromethanesulfonate

(35) TABLE-US-00002 TABLE 2 Comparison table of each product in storage stability and color number NCO % after 8 h Hasson color initial NCO degradation number of of the at high the product product NCO % stored at 30° C. temperature (color number) terminator % 1 month 2 months 6 months (80° C.) initial 2 months Comparative diphenyldifluorosilane 28.88 28.82 28.71 28.53 28.12 20 30 Example 1 Example 1 diphenyldifluorosilane/ 28.93 28.91 28.88 28.72 28.72 20 25 p-toluenesulfonic anhydride Example 2 diphenyldichlorosilane/ 28.87 28.85 28.78 28.68 28.65 30 35 trifluoromethanesulfonic anhydride Example 3 tritylfluorosilane/ 28.89 28.87 28.83 28.78 28.79 30 35 p-toluenesulfonic anhydride Example 4 diphenyldifluorosilane/ 28.87 28.81 28.79 28.74 28.75 30 35 trifluoromethanesulfonic anhydride Comparative trimethylsilyl 28.85 28.72 28.53 28.31 27.53 150 180 Example 2 trifluoromethanesulfonate Comparative trimethylsilyl 28.82 28.77 28.62 28.46 27.88 50 60 Example 3 trifluoromethanesulfonate/ dibutyl phosphate Comparative p-toluenesulfonic anhydride 28.91 28.21 28.03 27.24 26.56 40 70 Example 4 Comparative methyl 28.91 28.61 28.28 27.14 26.35 140 150 Example 5 trifluoromethanesulfonate

(36) Referring to Comparative Example 2, the modified isocyanate product has a high appearance color number and its high temperature stability is not ideal; the modified isocyanate products of Comparative Examples 3-5 have ideal storage stability at room temperature, but the stability is not ideal at high temperature, and NCO decreases significantly and viscosity increases greatly; it can be seen from Comparative Example 1 that by using of diphenyldifluorosilane alone, the stability at high temperature is poor; Examples 1-4 show that after compounding halosilane organic with p-toluenesulfonic anhydride, the stability is ideal at both room temperature and high temperature, and the color number is also lower than that in other examples.