A cyclodextrin composition and its use

Abstract

The present application relates to isocyanate compounds, and particularly relates to a cyclodextrin composition used as a storage stabilizer for isocyanate compounds, which comprises cyclodextrin and avobenzone. The cyclodextrin composition of an embodiment of the present application, used as a storage stabilizer for isocyanate compounds, can keep isocyanate compounds from yellowing after long-time storage, and improves the storage stability of isocyanate compounds.

Description

Technical Field

[0001] This invention relates to isocyanate compounds, and more particularly to a cyclodextrin composition that can improve the storage stability of isocyanates. Background Technology

[0002] Isocyanates are typically prepared by reacting amines with phosgene after a condensation reaction to produce polyamines. Based on their chemical structure, isocyanates can be classified into aromatic isocyanates and aliphatic isocyanates. The production process of diisocyanates is relatively complex and generates color-causing substances at the ppm level, such as aldehydes, ketones, chlorinated compounds, and nitrogen-containing substances. These substances cause yellowing of diisocyanate products during storage due to prolonged exposure to light and time, resulting in a yellow color that affects their usability. Summary of the Invention

[0003] To overcome at least one of the defects of the prior art, in a first aspect, one embodiment of the present invention provides a cyclodextrin composition comprising cyclodextrin and avobenzone.

[0004] Secondly, one embodiment of the present invention provides the application of the above-described cyclodextrin composition as a stabilizer for isocyanate compounds.

[0005] Thirdly, one embodiment of the present invention provides an isocyanate composition comprising the above-described cyclodextrin composition and isocyanate compounds.

[0006] The cyclodextrin composition of one embodiment of the present invention is used as a storage stabilizer for isocyanate compounds, which enables isocyanate compounds to remain free from yellowing after long-term storage, thereby improving the storage stability of isocyanate compounds. Detailed Implementation

[0007] Typical embodiments embodying the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the description herein is for illustrative purposes only and not intended to limit the present invention.

[0008] One embodiment of the present invention provides a cyclodextrin composition comprising cyclodextrin and avobenzone.

[0009] In one embodiment, the mass ratio of cyclodextrin to avobenzone is (0.1–10.0):10, and may further be (1–3):3, for example 0.3:3, 0.5:3, 1:3, 1.2:3, 1.5:3, 1.8:3, 2:3, 2.2:3, 2.5:3, 2.8:3, 3:3.

[0010] In one embodiment, the avobenzone (4-tert-butyl-4-methoxydibenzoylmethane, abbreviated as AVB) used in the cyclodextrin composition is an existing compound obtained by ester condensation reaction of p-methoxyacetophenone and p-tert-butylbenzoate, and its structural formula is as follows:

[0011]

[0012] In one embodiment, cyclodextrin (CD) is a class of organic compounds that are cyclic oligosaccharides formed from amylose by the action of cyclodextrin glucosyltransferase produced by Bacillus, typically containing 6 to 12 D-glucan units. Cyclodextrins containing 6, 7, and 8 glucose units are referred to as α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin, respectively.

[0013] In one embodiment, the cyclodextrin used in the cyclodextrin composition includes one, two, or three of α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin, and the structural formulas of α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin are as follows:

[0014]

[0015]

[0016] In one embodiment of the cyclodextrin composition of the present invention, the cyclodextrin has the property of being hydrophilic on the outer edge and hydrophobic on the inner cavity, which can form cavities within the molecule and form stable inclusion complexes with avobenzone through non-covalent bonds, thereby enhancing the photostability of avobenzone. Mixing isocyanate compounds with the cyclodextrin composition can prevent ultraviolet light from contacting the isocyanate groups, thus preventing the isocyanate compounds from yellowing over a longer period and improving their storage stability.

[0017] One embodiment of the present invention provides the application of the above-described cyclodextrin composition as a stabilizer (or anti-yellowing agent) for isocyanate compounds.

[0018] One embodiment of the present invention provides an isocyanate composition comprising the above-described cyclodextrin composition and isocyanate compounds.

[0019] In one embodiment, the isocyanate compound includes one or more of aliphatic isocyanates, alicyclic isocyanates, aromatic isocyanates, and derivatives of the above isocyanates, wherein the isocyanate derivatives all contain an isocyanate group. Further, the aliphatic or alicyclic isocyanate may contain 8 to 36 carbon atoms; for example, the number of carbon atoms in the aliphatic or alicyclic isocyanate may be 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, or 35. The aromatic isocyanate may contain 7 to 20 carbon atoms; for example, the number of carbon atoms in the aromatic isocyanate may be 8, 10, 12, 14, 15, 16, or 18.

[0020] In one embodiment, the isocyanate compound includes one or more of diisocyanate and diisocyanate derivatives, wherein the diisocyanate derivatives contain isocyanate groups; the diisocyanate derivatives include urethane of diisocyanate, carbodiimide-modified diisocyanate (e.g., carbodiimide-modified MDI), and isocyanate prepolymers, wherein the isocyanate prepolymers are obtained by reacting diisocyanate with a polyol having active hydrogen (e.g., polyether polyol), and the isocyanate prepolymers contain isocyanate groups.

[0021] In one embodiment, the diisocyanate includes one or more of diphenylmethane diisocyanate (MDI), toluene diisocyanate (TDI), and hexamethylene diisocyanate (HDI).

[0022] In one embodiment, the mass ratio of the cyclodextrin composition to the isocyanate compound can be (0.004–1.0):100, more preferably (0.004–0.02):100, for example 0.005:100, 0.006:100, 0.007:100, 0.01:100, 0.012:100, 0.015:100, 0.016:100, 0.017:100, 0.018:100, 0.05:100, 0.1:100, 0.2:100, 0.5:100, or 0.8:100.

[0023] The cyclodextrin composition of one embodiment of the present invention is used as a storage stabilizer for isocyanate compounds, which enables the isocyanate compounds to retain their colorless or light-colored transparent properties after long-term storage, inhibits yellowing, improves the storage stability of isocyanate compounds, and enhances the quality of isocyanate compound products.

[0024] The cyclodextrin composition of one embodiment of the present invention is used as a storage stabilizer for isocyanate compounds, which can prolong the yellowing time of isocyanates and their compositions (or derivatives), thereby prolonging their storage period in air and reducing the impact of yellowing on the quality of isocyanate products during use and processing.

[0025] The application of the cyclodextrin composition according to one embodiment of the present invention will be further described below with reference to the embodiments. The raw materials and test methods involved in each embodiment and comparative example are as follows:

[0026] 1. Raw materials

[0027] MDI-50: A product of Wanhua Chemical Group Co., Ltd.

[0028] MDI-100: A product of Wanhua Chemical Group Co., Ltd.

[0029] Carbodiimide-modified MDI: Brand name CDMDI-100L, product of Wanhua Chemical Group Co., Ltd.

[0030] Polyether polyol: Grade C2020, a product of Wanhua Chemical Group Co., Ltd.

[0031] HDI: A product of Wanhua Chemical Group Co., Ltd.

[0032] TDI-80: A product of Wanhua Chemical Group Co., Ltd.

[0033] Avobenzone: a Maclean reagent product;

[0034] Cyclodextrin: Maclean's reagent product.

[0035] 2. Testing Methods

[0036] - The NCO content was determined according to the People's Republic of China Chemical Industry Standard "Determination Method of Isocyanate Group Content in Polyurethane Prepolymers or Intermediate Products".

[0037] Example 1-1

[0038] 0.02 g of α-cyclodextrin and 0.03 g of avobenzone were added to 1000 g of MDI50 and stirred evenly. 300 g of the mixture was weighed into a 500 mL glass bottle, sealed and stored in a constant temperature oven at 45 °C. The appearance color of the mixture was observed every 12 hours to obtain the time when the system began to turn yellow. The results are shown in Table 1.

[0039] Examples 1-2

[0040] This embodiment uses essentially the same raw materials and processes as Example 1-1, the only difference being that β-cyclodextrin of the same mass is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0041] Examples 1-3

[0042] This embodiment uses essentially the same raw materials and processes as Example 1-1, the only difference being that γ-cyclodextrin of the same mass is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0043] Example 2-1

[0044] 0.02 g of α-cyclodextrin and 0.03 g of avobenzone were added to 1000 g of MDI100 and stirred evenly. 300 g of the mixture was weighed using a 500 mL beaker, sealed and stored in a constant temperature oven at 45 °C. The appearance color of the mixture was observed every 12 hours to obtain the time when the system began to turn yellow. The results are shown in Table 1.

[0045] Example 2-2

[0046] This embodiment uses essentially the same raw materials and processes as Example 2-1, the only difference being that the same mass of β-cyclodextrin is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0047] Example 2-3

[0048] This embodiment uses essentially the same raw materials and processes as Example 2-1, the only difference being that γ-cyclodextrin of the same mass is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0049] Example 3-1

[0050] This embodiment uses essentially the same raw materials and processes as Example 2-1, the only difference being that the same mass of HDI is used instead of MDI100. The test results regarding the time it takes for the system to begin yellowing are shown in Table 1.

[0051] Example 3-2

[0052] This embodiment uses essentially the same raw materials and processes as Example 3-1, the only difference being that β-cyclodextrin of the same mass is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0053] Example 3-3

[0054] This embodiment uses essentially the same raw materials and processes as Example 3-1, the only difference being that γ-cyclodextrin of the same mass is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0055] Example 4-1

[0056] This embodiment uses essentially the same raw materials and processes as Example 2-1, the only difference being that CDMDI-100L of the same quality is used instead of MDI100. The test results regarding the time it takes for the system to begin yellowing are shown in Table 1.

[0057] Example 4-2

[0058] This embodiment uses essentially the same raw materials and processes as Example 4-1, the only difference being that the same mass of β-cyclodextrin is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0059] Example 4-3

[0060] This embodiment uses essentially the same raw materials and processes as Example 4-1, the only difference being that the same mass of γ-cyclodextrin is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0061] Example 5-1

[0062] A urethane prepolymer was prepared by reacting TDI-80 with polyether polyol C2020. The specific process was as follows: 442g of TDI-80 was added to a four-necked flask and kept at a constant temperature of 55°C in an oil bath. When the material temperature reached 50°C, 558g of polyether polyol C2020 was added to the flask, mechanical stirring was started, and the material temperature was raised to 80°C through the oil bath. The reaction was carried out at this temperature for 3 hours. The product was a prepolymer with an isocyanate group (-NCO) content of 18.98wt%.

[0063] Weigh 300g of prepolymer using a 500mL beaker, add 0.02g of α-cyclodextrin and 0.03g of avobenzone to the prepolymer, stir the mixture evenly, seal and store in a constant temperature oven at 45℃, observe the appearance color of the mixture every 12 hours to obtain the time when the system begins to yellow, and the results are shown in Table 1.

[0064] Example 5-2

[0065] This embodiment uses essentially the same raw materials and processes as Example 5-1, the only difference being that β-cyclodextrin of the same mass is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0066] Example 5-3

[0067] This embodiment uses essentially the same raw materials and processes as Example 5-1, the only difference being that γ-cyclodextrin of the same mass is used instead of α-cyclodextrin. The test results regarding the time to the onset of yellowing are shown in Table 1.

[0068] Example 6

[0069] 0.01 g of β-cyclodextrin and 0.03 g of avobenzone were added to 1000 g of MDI 50 and stirred evenly. 300 g of the mixture was weighed into a 500 mL glass bottle, sealed and stored in a constant temperature oven at 45 °C. The appearance color of the mixture was observed every 12 hours to obtain the time when the system began to turn yellow. The results are shown in Table 1.

[0070] Example 7

[0071] 0.03 g of β-cyclodextrin and 0.03 g of avobenzone were added to 1000 g of MDI 50 and stirred evenly. 300 g of the mixture was weighed into a 500 mL glass bottle, sealed and stored in a constant temperature oven at 45 °C. The appearance color of the mixture was observed every 12 hours to obtain the time when the system began to turn yellow. The results are shown in Table 1.

[0072] Comparative Example 1

[0073] Weigh 300g of MDI-50 into a 500mL glass bottle, seal it, and store it in an oven at 45℃. Observe the appearance and color of the product every 12 hours to obtain the time when the system begins to yellow. See Table 1 for the test results regarding the time when the system begins to yellow.

[0074] Comparative Example 2

[0075] Weigh 300g of MDI-100 into a 500mL glass bottle, seal it, and store it in a constant temperature oven at 45℃. Observe the appearance color of the mixture every 12 hours to obtain the time when the system begins to turn yellow. The results are shown in Table 1.

[0076] Comparative Example 3

[0077] Weigh 300g of HDI in a 500mL beaker and store it in an oven at 45℃. Observe the appearance color of the product every 12 hours to obtain the time when the system begins to turn yellow. The results are shown in Table 1.

[0078] Comparative Example 4

[0079] Weigh 300g of CDMDI-100L in a 500mL beaker and store it in an oven at 45℃. Observe the appearance color of the product every 12 hours to obtain the time when the system begins to yellow. The results are shown in Table 1.

[0080] Comparative Example 5

[0081] A urethane prepolymer was prepared by reacting TDI-80 with polyether polyol C2020. The specific process was as follows: 442g of TDI-80 was added to a four-necked flask and kept at a constant temperature of 55°C in an oil bath. When the material temperature reached 50°C, 558g of polyether polyol C2020 was added to the flask, mechanical stirring was started, and the material temperature was raised to 80°C through the oil bath. The reaction was carried out at this temperature for 3 hours. The product was a prepolymer with an isocyanate group (-NCO) content of 18.98wt%.

[0082] Weigh 300g of the prepolymer into a 500mL glass bottle, seal it, and store it in an oven at 45℃. Observe the appearance color every 12 hours to obtain the time when the system begins to yellow. The results are shown in Table 1.

[0083] Comparative Example 6

[0084] Add 0.03g of avobenzone to 1000g of MDI50 and stir well. Weigh 300g of the mixture into a 500mL glass bottle, seal it and store it in a constant temperature oven at 45℃. Observe the appearance color of the mixture every 12 hours to obtain the time when the system begins to turn yellow. The results are shown in Table 1.

[0085] Comparative Example 7

[0086] 0.03 g of UV absorber UV-1 (N-(ethoxycarbonylphenyl)-N'-methyl-N'-phenylformamidin) was added to 1000 g of MDI 50 and stirred until homogeneous. 300 g of the mixture was weighed into a 500 mL glass bottle, sealed, and stored in a constant temperature oven at 45 °C. The appearance color of the mixture was observed every 12 hours to obtain the time when the system began to yellow. The results are shown in Table 1.

[0087] Comparative Example 8

[0088] 0.03 g of UV absorber R-455 (2-hydroxy-2-methyl-1-phenyl-1-propanone) was added to 1000 g of MDI50 and stirred evenly. 300 g of the mixture was weighed into a 500 mL glass bottle, sealed and stored in a constant temperature oven at 45 °C. The appearance color of the mixture was observed every 12 hours to obtain the time when the system began to yellow. The results are shown in Table 1.

[0089] Comparative Example 9

[0090] 0.02 g of α-cyclodextrin and 0.03 g of UV absorber UV-1 (N-(ethoxycarbonylphenyl)-N'-methyl-N'-phenylformamidin) were added to 1000 g of MDI50 and stirred evenly. 300 g of the mixture was weighed into a 500 mL glass bottle, sealed, and stored in a constant temperature oven at 45 °C. The appearance color of the mixture was observed every 12 hours to obtain the time when the system began to yellow. The results are shown in Table 1.

[0091] Table 1. Types of stabilizers and yellowing results for each example and comparative example.

[0092]

[0093] As shown in Table 1, compared to Comparative Examples 1 to 5, Examples 1-1 to 5-3, by adding cyclodextrin and avobenzone to the isocyanate compounds, extended their shelf life in air and reduced the risk of yellowing during use and processing. Furthermore, the combination of β-cyclodextrin and avobenzone exhibited even better anti-yellowing effects.

[0094] Avobenzone, UV absorber UV-1, and UV absorber R-455 were added to the isocyanate compounds in Comparative Examples 6, 7, and 8, respectively. The results in Table 1 show that the yellowing time of these isocyanate compounds was later than that of Comparative Examples 1 to 5, but still significantly earlier than that of Examples 1-1 to 5-3. Comparative Example 8 used both cyclodextrin and UV absorber UV-1 as stabilizers. Although it enhanced the anti-yellowing effect compared to Comparative Example 7, the yellowing time was still significantly earlier than that of Examples 1-1 to 5-3.

[0095] In addition, Comparative Example 9 used a combination of α-cyclodextrin and UV absorber UV-1 as a storage stabilizer for isocyanate compounds. The results showed that although the yellowing time of the isocyanate compounds (after 60 h) was delayed compared with the yellowing time of Comparative Example 7 without the use of cyclodextrin, it was still significantly earlier than the yellowing time of Examples 1-1 to 5-3 (after at least 100 h).

[0096] Therefore, using cyclodextrin and avobenzone as a storage stabilizer for isocyanate compounds, compared with other UV absorbers or combinations of cyclodextrin and other UV absorbers, enables isocyanate compounds to remain free from yellowing after longer storage, thus improving the storage stability of isocyanate compounds.

[0097] Unless otherwise specified, the terms used in this invention have the meanings commonly understood by those skilled in the art.

[0098] The embodiments described in this invention are for illustrative purposes only and are not intended to limit the scope of protection of this invention. Those skilled in the art can make various other substitutions, changes and improvements within the scope of this invention. Therefore, this invention is not limited to the above embodiments, but is only defined by the claims.

Claims

1. Use of a cyclodextrin composition as a stabilizer for isocyanate-based compounds, characterized in that, The cyclodextrin composition comprises cyclodextrin and avobenzone, and the mass ratio of the cyclodextrin to the avobenzone is (0.1-10.0):

10.

2. Use according to claim 1, characterized in that, The cyclodextrin comprises one, two or three of α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin; and / or, The mass ratio of the cyclodextrin to the avobenzone is (1-3):

3.

3. An isocyanate composition, characterized in that, The cyclodextrin composition comprises cyclodextrin and avobenzone, and the mass ratio of the cyclodextrin to the avobenzone is (0.1-10.0):

10.

4. The composition of claim 3, wherein, The cyclodextrin comprises one, two or three of α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin; and / or, The mass ratio of the cyclodextrin to the avobenzone is (1-3):

3.

5. The composition of claim 3, wherein, The isocyanate compound comprises one or more of aliphatic isocyanate, alicyclic isocyanate, aromatic isocyanate and derivatives thereof, and the derivatives of the aliphatic isocyanate, the derivatives of the alicyclic isocyanate and the derivatives of the aromatic isocyanate all comprise isocyanate groups.

6. The composition of claim 5, wherein, The isocyanate compound comprises diisocyanate and derivatives of diisocyanate; and / or, The aliphatic isocyanate and / or the alicyclic isocyanate comprise 8-36 carbon atoms; and / or, The aromatic isocyanate comprises 7-20 carbon atoms.

7. The composition of claim 6, wherein, The diisocyanate comprises one or more of diphenylmethane diisocyanate, toluene diisocyanate and hexamethylene diisocyanate; and / or, The derivatives of the diisocyanate comprise urethane of the diisocyanate, carbodiimide-modified diisocyanate and isocyanate prepolymer obtained by reacting polyol with the diisocyanate, and the derivatives of the diisocyanate comprise isocyanate groups.

8. The composition of claim 3, wherein, The mass ratio of the cyclodextrin composition to the isocyanate compound is (0.004-1.0):

100.

9. The composition of claim 3, wherein, The mass ratio of the cyclodextrin composition to the isocyanate compound is (0.004-0.02):100.

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