TWI701231B - Compound and process for preparing the same - Google Patents

Abstract

A compound and a process for preparing the compound are provided. The compound is represented by the formula (1):

in formula (I), X₁ and X₂ represent a group represented by the formula (1-1) or formula (1-2),

in formula (1-1), R¹ represents C1-C5 alkyl group, m represents an integer of 1 to 10, wherein when m is 2 or more, a plurality of R¹ may be the same or different, n represents an integer of 1 to 6, q represents an integer of 1 to 3, * respectively represent a linkage bond,

in formula (1-2), R² represents C1-C5 alkyl group or alkoxy carbonyl group, R³ and R⁴ respectively represents hydrogen atom or C1-C5 alkyl group, p represents an integer of 0 to 10, * respectively represent a linkage bond, and Y₁ and Y₂ represent C1-C4 alkylene group.

Description

Compound and its preparation method

This disclosure is about a compound and its preparation method.

Self-healing paint is a kind of paint. Its characteristic is that after a certain external force (such as light or heat) is applied to the paint film, the paint itself can produce a self-recovering function, so that the film can be flattened or even damaged. Heal the scars of the coating film. Since the coating film is required to "flow" or "rebound" to repair the damage after being affected by external forces, the resin system of the coating film needs a certain degree of flexibility.

Disulfide bonds exist in amino acids in nature and play important functions in organisms. Due to its unique bonding method, the disulfide bond has been proven to undergo self-oxidation-reduction reactions to cause the exchange of disulfide bond functional groups between two molecules with disulfide bonds. Therefore, the introduction of disulfide bonds in the coating system can provide coating flexibility and make the coating have self-healing properties. In addition, hydrogen bonds are also considered to be functional groups that can provide self-healing properties.

However, in the existing polyurethane coating system, only attempts to introduce disulfide bonds in the chain extender to provide coating self-healing properties, but the chain extender cannot directly participate in the hardening reaction of the coating. Therefore, there is still a need to continue to develop compounds that have self-healing properties and can directly participate in the hardening reaction of coatings to facilitate application.

Based on the above, the present disclosure provides a compound whose structure has two isocyanate groups which can be used as a hardener and can provide self-healing properties.

式（1） 式（1）中， X₁ 及X₂ 表示式（1-1）或式（1-2）所示的基，

式（1-1） 式（1-1）中， R¹ 表示碳數為1至5的烷基， m表示0至10的整數，當m為2以上的情況下，多個R¹ 可相同亦可不同， n表示1至6的整數， q表示1至3的整數， *分別表示連接鍵，

式（1-2） 式（1-2）中， R² 表示碳數為1至5的烷基或烷氧羰基（alkoxy carbonyl group）， R³ 及R⁴ 各自獨立表示氫原子或碳數為1至5的烷基， p表示0至10的整數，當p為2以上的情況下，多個R³ 可相同亦可不同，多個R⁴ 可相同亦可不同， *分別表示連接鍵， Y₁ 及Y₂ 表示碳數為1至4的伸烷基。One aspect of the present disclosure relates to a compound having the structure shown in the following formula (1):

Formula (1) In formula (1), X ₁ and X ₂ represent groups represented by formula (1-1) or formula (1-2),

Formula (1-1) In formula (1-1), R ¹ represents an alkyl group having a carbon number of 1 to 5, and m represents an integer of 0 to 10. When m is 2 or more, multiple R ¹ may be the same It may be different, n represents an integer from 1 to 6, q represents an integer from 1 to 3, * represents a connecting bond, respectively,

Formula (1-2) In formula (1-2), R ² represents an alkyl group having 1 to 5 carbon atoms or an alkoxy carbonyl group, and R ³ and R ⁴ each independently represent a hydrogen atom or a carbon number of An alkyl group of 1 to 5, p represents an integer of 0 to 10. When p is 2 or more, multiple R ³ may be the same or different, multiple R ⁴ may be the same or different, * each represents a bonding bond, Y ₁ and Y ₂ represent an alkylene group having 1 to 4 carbon atoms.

或

，*分別表示連接鍵。In an embodiment of the present disclosure, the above X ₁ and X ₂ represent

or

, * Respectively indicate the connection key.

In an embodiment of the present disclosure, the aforementioned Y ₁ and Y ₂ represent a methylene group or an ethylene group.

式（1-a）

式（1-b）。In an embodiment of the present disclosure, the above-mentioned compound is a compound represented by formula (1-a) or a compound represented by formula (1-b),

Formula (1-a)

Formula (1-b).

式（2） 式（2）中， X表示式（1-1）或式（1-2）所示的基，

式（1-1） 式（1-1）中， R¹ 表示碳數為1至5的烷基， m表示0至10的整數，當m為2以上的情況下，多個R¹ 可相同亦可不同， n表示1至6的整數， q表示1至3的整數， *分別表示連接鍵，

式（1-2） 式（1-2）中， R² 表示碳數為1至5的烷基或烷氧羰基， R³ 及R⁴ 各自獨立表示氫原子或碳數為1至5的烷基， p表示0至10的整數，當p為2以上的情況下，多個R³ 可相同亦可不同，多個R⁴ 可相同亦可不同， *分別表示連接鍵，

式（3） 式（3）中，Y₁ 及Y₂ 表示碳數為1至4的伸烷基。Another aspect of the present disclosure relates to a method for preparing a compound, which is to make a diisocyanate compound represented by formula (2) and a diisocyanate compound represented by formula (3) in the presence of a dialkyl substituted amine solvent and a catalyst The disulfide compound is subjected to a decarbonation condensation reaction, wherein the catalyst is an organic magnesium salt, an organic calcium salt or a combination thereof.

Formula (2) In formula (2), X represents the group represented by formula (1-1) or formula (1-2),

Formula (1-1) In formula (1-1), R ¹ represents an alkyl group having a carbon number of 1 to 5, and m represents an integer of 0 to 10. When m is 2 or more, multiple R ¹ may be the same It may be different, n represents an integer from 1 to 6, q represents an integer from 1 to 3, * represents a connecting bond, respectively,

Formula (1-2) In formula (1-2), R ² represents an alkyl group having 1 to 5 carbons or an alkoxycarbonyl group, and R ³ and R ⁴ each independently represent a hydrogen atom or an alkane having 1 to 5 carbons. The base, p represents an integer from 0 to 10. When p is 2 or more, multiple R ³ may be the same or different, multiple R ⁴ may be the same or different, * each represents a bonding bond,

Formula (3) In formula (3), Y ₁ and Y ₂ represent an alkylene group having 1 to 4 carbon atoms.

In an embodiment of the present disclosure, the above-mentioned dialkyl substituted amide solvents are dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), and N- N-methylpyrrolidone (NMP) or a combination thereof.

In an embodiment of the present disclosure, compared to the total amount of the diisocyanate compound represented by the formula (2) and the disulfide compound represented by the formula (3) being 100 parts by weight, the content of the catalyst It is 0.05 to 0.1 parts by weight.

In an embodiment of the present disclosure, the diisocyanate compound represented by the above formula (2) is Isophorone diisocyanate (IPDI), L-Lysine Diisocyanate (L-Lysine Diisocyanate) Or a combination.

In an embodiment of the present disclosure, the disulfide compound represented by formula (3) above is 2,2'-dithiodiacetic acid (2,2'-dithiodiacetic acid), 3,3'-dithiodiacetic acid Dipropionic acid (3,3'-dithiodipropionic acid) or a combination thereof.

In an embodiment of the present disclosure, in the presence of a catalyst, the reaction temperature of the aforementioned decarbonation condensation reaction is 60°C to 120°C.

The compound provided in the present disclosure has two cyanate groups and can be used as a hardener, has a disulfide bond and can exchange between molecules to provide self-repairing properties, and has an amide bond that can form hydrogen bonds to enhance self-repair. characteristic. At the same time, the structure of the compound disclosed in the present disclosure does not contain aromatic rings, which can avoid product yellowing, so it can be widely used in the formulation of various resins or coatings, while providing self-healing properties. In addition, the compound disclosed in the present disclosure can be stored more stably at room temperature, and can provide both hardening and self-healing properties, which is very suitable for industrial applications.

The decarbonation condensation reaction provided by the present disclosure uses a diisocyanate compound with an asymmetric structure to react with a disulfide compound with two carboxyl groups, so the two carboxyl groups on the disulfide compound can selectively react with only one of them. The isocyanate groups react. At the same time, the disulfide compound with two carboxyl groups as shown in formula (3) used in the decarbonation condensation reaction of the present disclosure is easy to store and transport, and is very suitable for industrial mass production.

In order to make the above-mentioned features and advantages of the present disclosure more obvious and understandable, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

式（1）。 式（1）中， X₁ 及X₂ 表示式（1-1）或式（1-2）所示的基，

式（1-1） 式（1-1）中， R¹ 表示碳數為1至5的烷基，較佳為甲基或乙基， m表示0至10的整數，當m為2以上的情況下，多個R¹ 可相同亦可不同， n表示1至6的整數， q表示1至3的整數，較佳為2的整數， *分別表示連接鍵，其中於立體阻礙較大的碳上的連接鍵較佳為鍵結至異氰酸基，於立體阻礙較小的碳上的連接鍵較佳為鍵結至醯胺鍵，

式（1-2） 式（1-2）中， R² 表示碳數為1至5的烷基或烷氧羰基， R³ 及R⁴ 各自獨立表示氫原子或碳數為1至5的烷基， p表示0至10的整數，較佳為1至8的整數，更佳為2至6的整數；當p為2以上的情況下，多個R³ 可相同亦可不同，多個R⁴ 可相同亦可不同， *分別表示連接鍵，其中於立體阻礙較大的碳上的連接鍵較佳為鍵結至異氰酸基，於立體阻礙較小的碳上的連接鍵較佳為鍵結至醯胺鍵， Y₁ 及Y₂ 表示碳數為1至4的伸烷基，較佳為亞甲基或伸乙基。The present disclosure provides a compound that can be used as a hardener. The compound has a structure represented by the following formula (1):

Formula 1). In formula (1), X ₁ and X ₂ represent groups represented by formula (1-1) or formula (1-2),

Formula (1-1) In formula (1-1), R ¹ represents an alkyl group having 1 to 5 carbon atoms, preferably methyl or ethyl, m represents an integer from 0 to 10, when m is 2 or more In the case, a plurality of R ¹ may be the same or different, n represents an integer from 1 to 6, q represents an integer from 1 to 3, preferably an integer of 2, *respectively represents a linking bond, in which the sterically hindered carbon The connecting bond on is preferably bonded to a cyanate group, and the connecting bond on the carbon with less steric hindrance is preferably bonded to an amide bond,

Formula (1-2) In formula (1-2), R ² represents an alkyl group having 1 to 5 carbons or an alkoxycarbonyl group, and R ³ and R ⁴ each independently represent a hydrogen atom or an alkane having 1 to 5 carbons. Base, p represents an integer from 0 to 10, preferably an integer from 1 to 8, more preferably an integer from 2 to 6; when p is 2 or more, multiple R ³ may be the same or different, and multiple R ⁴ can be the same or different, *respectively represents the linkage, wherein the linkage on the carbon with larger steric hindrance is preferably bonded to the cyanate group, and the linkage on the carbon with lower steric hindrance is preferably Bonded to an amide bond, Y ₁ and Y ₂ represent an alkylene group having 1 to 4 carbon atoms, preferably a methylene group or an ethylene group.

In this context, the alkyl group having 1 to 5 carbon atoms may be methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, second butyl, tertiary butyl, n-pentyl , Isoamyl, etc., but not limited to this.

Here, the alkoxycarbonyl group may be ethoxycarbonyl, propoxycarbonyl, n-butoxycarbonyl, tertiary butoxycarbonyl, etc., but is not limited thereto.

In this article, the order of the size of the "stereo hindrance" of carbon is basically tertiary carbon>secondary carbon>primary carbon. It should be noted that there are exceptions such as: the opposite of the primary carbon to the bonding bond (*) The presence of secondary carbon or tertiary carbon on one side of the carbon may increase the steric hindrance of the primary carbon. Furthermore, the order of the size of carbon "stereo hindrance" can be presumed to be tertiary carbon>primary carbon where there is a secondary carbon or tertiary carbon on the opposite side of the bond (*)>secondary carbon>primary carbon .

In this article, "primary carbon" refers to a carbon atom with one carbon atom attached, "secondary carbon" refers to a carbon atom with two carbon atoms attached, and "tertiary carbon" refers to a carbon with three carbon atoms attached. atom.

式（I）

式（II） 式（I）及式（II）中，*分別表示連接鍵。In the exemplary embodiment of the present disclosure, X ₁ and X ₂ are groups represented by the following formula (I) or groups represented by the formula (II),

Formula (I)

Formula (II) In formula (I) and formula (II), * represents a connecting bond, respectively.

When X ₁ and X ₂ are groups represented by the formula (I), since the side of the primary carbon opposite to the bonding bond (*) is a tertiary carbon, the steric hindrance of the primary carbon increases, so in the formula In (I), the linkage (*) on the primary carbon is bonded to the cyanate group, and the linkage (*) on the secondary carbon is bonded to the amide bond.

When X ₁ and X ₂ are groups represented by formula (II), since the side of the primary carbon opposite to the bonding bond (*) is also the primary carbon, the primary carbon of the bonding bond (*) The three-dimensional obstacle will not increase. Therefore, in formula (II), the linkage (*) on the primary carbon is bonded to the cyanate group, and the linkage (*) on the secondary carbon is bonded to the amide bond.

式（1-a）

式（1-b）。More specifically, in the exemplary embodiments of the present disclosure, specific examples of the compound represented by formula (1) include formula (1-a) and formula (1-b), but are not limited thereto.

Formula (1-a)

Formula (1-b).

The compound provided by the present disclosure has two cyanate groups and can be used as a hardener, has a disulfide bond and can exchange between molecules to provide self-repairing properties, and has an amide bond that can form hydrogen bonds to enhance self-repair. effect. At the same time, the structure of the compound disclosed in the present disclosure does not contain aromatic rings, which can avoid yellowing of the product, so it can be used in the formulation of various resins or coatings and provide self-repairing properties. In addition, the disclosed compound can be stored more stably at room temperature, and can provide both hardening and self-repair properties at the same time, which is very suitable for industrial applications. Preparation method of compound represented by formula ( 1 )

式（2） 式（2）中， X表示式（1-1）或式（1-2）所示的基，

式（1-1） 式（1-1）中， R¹ 表示碳數為1至5的烷基， m表示0至10的整數，當m為2以上的情況下，多個R¹ 可相同亦可不同， n表示1至6的整數， q表示1至3的整數， *分別表示連接鍵，

式（1-2） 式（1-2）中， R² 表示碳數為1至5的烷基或烷氧羰基， R³ 及R⁴ 各自獨立表示氫原子或碳數為1至5的烷基， p表示0至10的整數，當p為2以上的情況下，多個R³ 可相同亦可不同，多個R⁴ 可相同亦可不同， *分別表示連接鍵，

式（3） 式（3）中，Y₁ 及Y₂ 表示碳數為1至4的伸烷基，較佳為亞甲基或伸乙基。The method for preparing the compound of the exemplary embodiment of the present disclosure includes the following steps: in the presence of a dialkyl-substituted amine solvent and a catalyst, the diisocyanate compound represented by formula (2) is combined with formula (3) The disulfide compound shown undergoes decarbonation condensation reaction,

Formula (2) In formula (2), X represents the group represented by formula (1-1) or formula (1-2),

Formula (1-1) In formula (1-1), R ¹ represents an alkyl group having a carbon number of 1 to 5, and m represents an integer of 0 to 10. When m is 2 or more, multiple R ¹ may be the same It may be different, n represents an integer from 1 to 6, q represents an integer from 1 to 3, * represents a connecting bond, respectively,

Formula (1-2) In formula (1-2), R ² represents an alkyl group having 1 to 5 carbons or an alkoxycarbonyl group, and R ³ and R ⁴ each independently represent a hydrogen atom or an alkane having 1 to 5 carbons. The base, p represents an integer from 0 to 10. When p is 2 or more, multiple R ³ may be the same or different, multiple R ⁴ may be the same or different, * each represents a bonding bond,

Formula (3) In the formula (3), Y ₁ and Y ₂ represent an alkylene group having 1 to 4 carbon atoms, preferably methylene or ethylene.

Basically, the description of X in formula (2) is the same as that of X ₁ and X ₂ in formula (1), and will not be repeated here.

In the exemplary embodiment of the present disclosure, the diisocyanate compound represented by formula (2) may be Isophorone diisocyanate (IPDI), L-Lysine Diisocyanate (L-Lysine Diisocyanate) Or similar. Since the diisocyanate compound represented by formula (2) has an asymmetric structure and the reactivity of the two isocyanate groups is different, when reacting with the disulfide compound represented by formula (3), the equivalent weight and reaction conditions can be used The control allows the synthesis to proceed in one step and avoids undesirable side reactions. At the same time, the diisocyanate compound represented by formula (2) does not have an aromatic ring structure, so yellowing of the product can be avoided.

In an exemplary embodiment of the present disclosure, the disulfide compound represented by formula (3) may be 2,2'-dithiodiacetic acid (2,2'-dithiodiacetic acid), 3,3'-dithiodiacetic acid Dipropionic acid (3,3'-dithiodipropionic acid) or similar. 3,3'-dithiodipropionic acid (3,3'-dithiodipropionic acid) is a commercially available industrial grade product, easy to obtain, it is a solid, easy to transport, odorless, and soluble in dialkyl substituted amine solvents And it is transparent and colorless, especially suitable for industrial production.

Not all solvents can be used in the decarbonation condensation reaction of the present disclosure. The structure of the solvent needs to contain nitrogen atoms to assist the dissolution of the disulfide compound represented by formula (3), and the nitrogen atom of the solvent cannot contain active hydrogen, otherwise The solvent itself reacts with the diisocyanate compound represented by formula (2). Dialkyl-substituted amine solvents are solvents that meet the above conditions.

式（4） 式（4）中，R⁵ 及R⁶ 各自獨立地為甲基、乙基或丙基，R⁷ 為氫原子、甲基、乙基或丙基，R⁶ 及R⁷ 可連同其連接之碳與氮一起形成環。In the exemplary embodiment of the present disclosure, the dialkyl-substituted amine-based solvent refers to the compound represented by formula (4):

Formula (4) In formula (4), R ⁵ and R ⁶ are each independently a methyl group, an ethyl group or a propyl group, R ⁷ is a hydrogen atom, a methyl group, an ethyl group, or a propyl group, and R ⁶ and R ⁷ may be combined The connected carbon and nitrogen together form a ring.

For example, the dialkyl substituted amide solvent can be dimethylformamide (Dimethylformamide, DMF), N,N-dimethylacetamide (Dimethylacetamide, DMAC), N,N-diethyl ethyl amide Amide, N,N-dipropylacetamide, N-methylpyrrolidone (NMP) or a combination thereof, but not limited thereto. In particular, N,N-Dimethylacetamide (DMAC) has low toxicity, is environmentally friendly and has low cost, and is particularly suitable for the present disclosure.

In the exemplary embodiment of the present disclosure, the decarbonation condensation reaction is carried out in the presence of a catalyst. In addition to accelerating the reaction rate, the catalyst can also increase the selectivity of the reaction, enable the reactants to undergo decarbonation condensation reaction, and reduce the occurrence of other side reactions (for example, the self-cyclization reaction of the diisocyanate compound represented by formula (2)).

In the exemplary embodiment of the present disclosure, the applicable catalyst may be an organic metal salt, such as an organic magnesium salt, an organic calcium salt, or a combination thereof. The catalyst is preferably Magnesium stearate, Magnesium octoate, Calcium stearate, Calcium octoate, Calcium isooctanoate, or a combination thereof, but is not limited thereto.

When a catalyst is used in the decarbonation condensation reaction, the reaction time can be significantly shortened and the selectivity of the reaction can be improved, and when an organic magnesium salt or organic calcium salt is used as a catalyst, the reaction can be significantly shortened compared to the case of no catalyst. Time to complete. It is worth noting that the catalysts often used in traditional polyurethane coating systems (for example, organotin such as dibutyltin dilaurate, organozinc or organic bismuth such as zinc octoate) cannot be catalyzed in the decarbonation condensation reaction of the present disclosure. effect.

In the exemplary embodiment of the present disclosure, compared to the total amount of the diisocyanate compound represented by formula (2) and the disulfide compound represented by formula (3) being 100 parts by weight, the usage amount of the catalyst is preferably 0.05 ~0.1 parts by weight. When the amount of the catalyst used is greater than 0.1 parts by weight, the reaction rate is too fast and it is not conducive to control, which is not suitable for industrial applications.

式（1-a）反應流程 2

式（1-b）For example, the decarbonation condensation reaction of the present disclosure can be the preparation of the compound represented by formula (1-a) in Reaction Scheme 1 or the preparation of the compound represented by formula (1-b) in Reaction Scheme 2. Reaction scheme 1

Formula (1-a) reaction process 2

Formula (1-b)

In the exemplary embodiment of the present disclosure, in the presence of a catalyst, the reaction temperature of the decarbonation condensation reaction is 60°C to 120°C, preferably 70°C to 110°C, more preferably 70°C to 100°C. When the reaction temperature exceeds 120°C, the reaction is too fast and difficult to control, resulting in side reactions, so the product is prone to yellowing. When the reaction temperature is lower than 60°C, the reaction energy is insufficient and the desired product and yield cannot be obtained.

In the exemplary embodiment of the present disclosure, the decarbonation condensation reaction refers to reacting the diisocyanate compound represented by formula (2) and the isocyanate group with the carboxyl group (-COOH) of the disulfide compound represented by formula (3) An amide bond is formed, and CO ₂ is removed at the same time during the reaction. The product is a diisocyanate with a disulfide bond and an amide bond in the structure. That is to say, by the preparation method of the compound disclosed in the present disclosure, a compound with disulfide bond, amide bond and isocyanate group can be formed in one step. <Example> An example of preparing a compound having the structure represented by formula ( 1 )

Hereinafter, Examples 1 to 4 and Comparative Example 1 to Comparative Example 5 for preparing the compound having the structure represented by formula (1) are described.

The compounds corresponding to the abbreviations in the following examples are described below. DTDPA: 3,3'-dithiodipropionic acid IPDI: isophorone diisocyanate DMF: dimethylformamide DMAC: N,N-dimethylacetamide DBTDL: dibutyltin dilaurate DBA: two Butylamine

Method for measuring the concentration of cyanate groups in the preparation method

In the method for preparing the compound of the present disclosure, one of the cyanate groups in the diisocyanate in the reactant will react with two carboxyl groups on the disulfide compound. Therefore, as the reaction progresses, the concentration of cyanic acid groups in the reaction will decrease. Therefore, in this disclosure, the degree of completion of the reaction is determined by measuring the change in the concentration of the cyanic acid group in the reaction. The measurement method is to first titrate a mixed solution of 519 mg of DBA, 2 ml of DMAC, and 1 drop of bromophenol blue indicator with 1N hydrochloric acid to obtain the purity of DBA, and then use DBA as the excess reagent and the cyanic acid group in the reaction solution Reaction and back titration of the unreacted amine groups of DBA with 1N hydrochloric acid to inversely deduce the weight percent concentration of the cyanic acid groups in the reaction solution. Such calibration can calculate the weight percent concentration of the cyanic acid group based on the sample sampled in the example. When the concentration of the cyanic acid group in the reaction reaches ±5% of the theoretical value of the concentration of the cyanic acid group when the reaction is completed, the reaction is judged to be complete. That is, if the theoretical value of the concentration of the cyanic acid group at the completion of the reaction is 11.75%, when the concentration of the cyanic acid group in the reaction is measured to be below 12.34%, the reaction is determined to be complete and the reaction is terminated. The above calibration method can also be used to determine the purity of the IPDI used in the reaction. After calibration, the purity of the IPDI used in the reaction was 97.23%.

Instance 1

式（1-a）Add 4.2 g (20 mmol) of DTDPA, 5.7 g (65 mmol) of dry DMAC, and 14 mg of calcium stearate to a double-necked flask with a condenser, and then heat to 100°C in an oil bath. Then 10.1 g (44 mmol) of IPDI (purity 97.23%) was added to the double-necked flask at once, and the reaction was carried out at 100°C. In this reaction mixture, the only reaction that can produce gas is the decarbonation reaction of isocyanate groups and carboxyl groups (-COOH). Therefore, the generation and number of bubbles can be used to determine whether the reaction is proceeding in the desired direction. During the reaction, the inlet of the double-neck flask was sealed with a rubber stopper, and the opening of the condenser was filled with a rubber stopper drilled with small holes, so that the carbon dioxide gas generated during the reaction could be discharged and the pressure balance in the reaction flask was maintained. After the reaction is completed, the compound represented by formula (1-a) is obtained.

Formula (1-a)

Figure 1 shows the (a) product, (b) solvent DMAC, (c) reactant IPDI, and (d) reaction of Example 1 obtained by using an infrared spectrometer (model FT-IR ALPHA II, Bruker Technology Co., Ltd.) Infrared spectrum of DTDPA.

First refer to the spectrum of (a) product and (d) reactant DTDPA. In the spectrum of product (a), the C=O strong absorption peak (1686 cm ^-1 ) from the carboxylic acid group of DTDPA completely disappeared after the reaction, showing The C=O absorption peak of carboxylic acid has completely reacted.

Secondly, (b) the strong absorption peak of the amino group C=O of the solvent DMAC appeared at 1631 cm ^-1 , which was close to the strong absorption peak of 1627 cm ^-1 in the product (a). Since the two reactants IPDI and DTDPA undergo the decarbonation reaction to form a new amide bond, the C=O absorption of the formed amide will coincide with the C=O absorption peak of the solvent DMAC, so the spectrum of the reaction product is only A strong absorption peak was observed at 1627 cm ^-1 .

In the spectrum of (c) IPDI, the absorption at 2243 cm ^-1 is a typical NCO group, while in the spectrum of (a) the product has the same strong absorption peak at 2252 cm ^-1 , which shows that the product still contains available for hardening The reacted NCO group is present.

In the spectrum of the product (a), a broad absorption peak appears at 3304 cm ^-1 , which represents the formation of an amide bond after the reaction. The absorption peak at 3304 cm ^-1 represents the NH absorption peak on the amido group, indicating that the reactants DTDPA and IPDI undergo decarbonization reaction as expected to form a new amido bond, so a new NH absorption peak appears in the IR spectrum.

Combining the comparison of infrared spectroscopy, the foaming condition of CO ₂ bubbles during the reaction, and the determination of the isocyanate group concentration can effectively prove that under the reaction conditions of Example 1, the reactants DTDPA and IPDI produce cost under the action of the catalyst. Invented the compound represented by formula (1-a).

Instance 2 :

Example 2 has the same experimental procedure as Example 1, except that 14 mg of magnesium stearate is used instead of calcium stearate.

Instance 3

Example 3 has the same experimental procedure as Example 2, except that the dosage of magnesium stearate is changed to 7 mg.

Instance 4

The experimental procedure of Example 4 is the same as that of Example 2, except that the reaction temperature is changed from 100°C to 70°C.

Comparative example 1

The experimental procedure of Comparative Example 1 is the same as that of Example 1, except that calcium stearate is not added as a catalyst.

Comparative example 2

The experimental procedure of Comparative Example 2 is the same as that of Example 1, except that 14 mg of DBTDL is substituted for calcium stearate.

Comparative example 3

The experimental procedure of Comparative Example 3 is the same as that of Example 1, except that 14 mg of zinc octoate is used instead of calcium stearate.

Comparative example 4

The experimental procedure of Comparative Example 4 is the same as that of Comparative Example 1, except that the reaction temperature is changed from 100°C to 60°C.

Comparative example 5

The experimental procedure of Comparative Example 5 is the same as that of Comparative Example 1, except that the reaction temperature is changed from 100°C to 70°C.

The reaction conditions and reaction time of Examples 1 to 4 and Comparative Examples 1 to 5 are summarized in Table 1 below. Table 1

As mentioned above, the carbon dioxide removal reaction is to determine whether the reaction is complete by measuring the concentration of the cyanic acid group in the reaction. However, there are many possible side reactions under the given reaction conditions, and these side reactions will cause the concentration of cyanic acid groups to decrease. Therefore, it is necessary to observe whether carbon dioxide gas is produced during the reaction at the same time to determine whether the reaction is proceeding toward the desired product.

According to the results of Example 1 and Example 2, when calcium stearate or magnesium stearate is used as a catalyst for the reaction, violent foaming can be clearly observed at the beginning of the reaction, indicating that the reaction is proceeding toward the desired decarbonization. . And after the reaction is carried out for 1-3 hours, the concentration of cyanic acid groups can reach ±5% of the theoretical value. In particular, when magnesium stearate is used as a catalyst, the concentration of cyanic acid groups can reach ±5% of the theoretical value after 1 hour of reaction. Also referring to Example 3, even if the usage amount of magnesium stearate is reduced to half of the usage amount of Example 2, the reaction time is only 2 hours. In contrast, in Comparative Example 1 to Comparative Example 3, after 6 hours of reaction, the concentration of the cyanic acid group in the reaction reached ±5% of the theoretical value of the concentration of the cyanic acid group at the completion of the reaction. No obvious carbon dioxide bubbles were observed during the reaction process of Example 1 to Comparative Example 3, indicating that the reason for the decrease in the concentration of cyanic acid groups in Comparative Example 1 to Comparative Example 3 may not be entirely due to the desired decarbonization Reaction, but contains the results caused by the simultaneous occurrence of other side reactions. That is, without adding a catalyst or adding a common catalyst such as DBTDL or zinc octoate as a catalyst, it is difficult to obtain the compound represented by formula (1-a).

In addition, when the reaction temperature drops to 70° C., Example 4 using magnesium stearate as a catalyst can still complete the reaction in 2.5 hours, and a large amount of carbon dioxide bubbles can be observed at the beginning of the reaction. In contrast, when the reaction temperature dropped to 60°C and 70°C, Comparative Example 4 and Comparative Example 5 where no catalyst was added only a very small amount of bubbles were observed at the beginning of the reaction. At the same time, after the reaction proceeded for six hours, the isocyanide The concentration of acid groups is still not close to the theoretical value, indicating that the reaction temperature is insufficient and the lack of catalyst reduces the selectivity and reactivity of the decarbonation reaction at the same time, so the concentration of isocyanate groups decreases slowly. That is to say, adding organic calcium or organic magnesium as a catalyst in the reaction improves the selectivity and reactivity of the carbon dioxide removal reaction, and allows the carbon dioxide removal reaction to proceed at a lower temperature.

In summary, the present disclosure provides a compound that can provide self-healing properties and be used as a hardening agent. At the same time, the structure of the compound does not contain aromatic rings, which can prevent yellowing of the product. In addition, the preparation method provided by the present disclosure can quickly and highly selectively prepare the compound of the present disclosure by using a specific starting material and a specific catalyst.

Although this disclosure has been disclosed in the above embodiments, it is not intended to limit the disclosure. Anyone with ordinary knowledge in the relevant technical field can make some changes and modifications without departing from the spirit and scope of this disclosure. Therefore, The scope of protection of this disclosure shall be subject to those defined by the attached patent scope.

no.

Figure 1 shows the infrared spectra of the (a) product, (b) solvent DMAC, (c) reactant IPDI, and (d) reactant DTDPA of Example 1.

Claims (8)

A compound having the structure represented by the following formula (1):

In formula (1), X ₁ and X ₂ represent

* Represents a bonding bond, respectively, and Y ₁ and Y ₂ represent an alkylene group having 1 to 4 carbon atoms. The compound described in item 1 of the scope of patent application, wherein Y ₁ and Y ₂ represent methylene or ethylene. The compound described in item 1 of the scope of patent application, which is a compound represented by formula (1-a) or a compound represented by formula (1-b),

A method for preparing a compound, which involves subjecting a diisocyanate compound and a disulfide compound represented by formula (3) to a decarbonation condensation reaction in the presence of a dialkyl-substituted amine solvent and a catalyst, wherein the The diisocyanate compound is isophorone diisocyanate, L-lysine diisocyanate or a combination thereof, and the catalyst is an organic magnesium salt, an organic calcium salt or a combination thereof,

In the formula (3), Y ₁ and Y ₂ represent an alkylene group having 1 to 4 carbon atoms. The method for preparing the compound described in item 4 of the scope of patent application, wherein the dialkyl substituted amine solvent is dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone Or a combination. The method for preparing the compound described in item 4 of the scope of the patent application, wherein the total amount of the diisocyanate compound and the disulfide compound represented by the formula (3) is 100 parts by weight, and the content of the catalyst It is 0.05 to 0.1 parts by weight. The method for preparing the compound described in item 4 of the scope of patent application, wherein the disulfide compound represented by the formula (3) is 2,2'-dithiodiacetic acid, 3,3'-dithiodipropylene Acid or a combination thereof. The method for preparing the compound described in item 4 of the scope of patent application, wherein the reaction temperature of the decarbonation condensation reaction is 60°C to 120°C.

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