阅读说明：本技术 一种聚脲预聚体的合成方法及其应用 (Synthetic method and application of polyurea prepolymer ) 是由 李斌仁 鲁晓东 许超平 陈林生 熊东路 肖增钧 徐涛 龙绪俭 于 2020-12-02 设计创作，主要内容包括：本发明涉及聚脲的合成技术领域,更具体地,本发明涉及一种聚脲预聚体的合成方法及其应用。本发明提供一种聚脲预聚体的合成方法,通过控制聚脲预聚体的亚胺基的结构,及和亚胺基相连的功能基团的结构,相比于常用的胺类预聚体,和异氰酸酯反应时具有更高的施工有效期。本发明制备得到的聚脲预聚体,通过一元胺、甲基丙烯酸酯和二元醇等常规的反应原料,可制备得到具有优良力学性能的产品,且相比于天冬聚脲,在具有相似或者更好施工有效期的产品,可降低成本。本发明提供的合成方法简单,具有高的产率,便于大批量生产。(The invention relates to the technical field of synthesis of polyurea, and particularly relates to a synthesis method and application of a polyurea prepolymer. Compared with the common amine prepolymer, the synthesis method of the polyurea prepolymer has higher construction validity period when reacting with isocyanate by controlling the structure of the imino group of the polyurea prepolymer and the structure of the functional group connected with the imino group. The polyurea prepolymer prepared by the invention can be prepared into products with excellent mechanical properties by using conventional reaction raw materials such as monoamine, methacrylate, dihydric alcohol and the like, and compared with the asparagus polyurea, the cost can be reduced when the products have similar or better construction validity. The synthesis method provided by the invention is simple, has high yield and is convenient for mass production.)

1. A synthesis method of a polyurea prepolymer is characterized in that the structural formula of the polyurea prepolymer is shown as formula (1):

R₁one or more selected from linear alkyl, cycloalkyl and alkyl ether;

R₂one or more selected from linear alkyl, cycloalkyl and aryl.

2. The method of synthesizing the polyurea prepolymer of claim 1, wherein R is₁The number of carbon atoms is less than 20.

3. The method of synthesizing the polyurea prepolymer of claim 1, wherein R is₂The number of carbon atoms is less than 10.

4. The synthesis method of the polyurea prepolymer according to any one of claims 1 to 3, wherein the polyurea prepolymer is prepared from binary methacrylate and monoamine;

the structural formula of the binary methacrylate is shown as the formula (2):

the structural formula of the monoamine is R₂-NH₂。

5. The method for synthesizing the polyurea prepolymer according to claim 4, wherein the molar ratio of the binary methacrylate to the monoamine is 1: (2.2-2.5).

6. The method for synthesizing the polyurea prepolymer according to claim 4, wherein the preparation method of the polyurea prepolymer comprises the following steps:

and (3) dropwise adding monoamine into binary methacrylate, reacting at 50-80 ℃, and then carrying out reduced pressure distillation to obtain the polyurea prepolymer.

7. The method for synthesizing the polyurea prepolymer according to claim 4, wherein the binary methacrylate is prepared from methacrylate and dihydric alcohol;

the structural formula of the methacrylate is shown as the formula (3):

r is alkyl;

the structural formula of the dihydric alcohol is HO-R₁-OH。

8. The method for synthesizing the polyurea prepolymer according to claim 7, wherein the molar ratio of the glycol to the methacrylate is 1: (4-6).

9. The method for synthesizing the polyurea prepolymer according to claim 7, wherein the method for preparing the binary methacrylate comprises the following steps:

mixing dihydric alcohol, methacrylate, a catalyst and a polymerization inhibitor, reacting at 100-130 ℃, and distilling under reduced pressure to obtain the binary methacrylate.

10. The application of the synthesis method of the polyurea prepolymer according to any one of claims 1 to 9, which is used for the synthesis of macromolecules.

Technical Field

The invention relates to the technical field of synthesis of polyurea, and particularly relates to a synthesis method and application of a polyurea prepolymer.

Background

Polyurea is a high polymer consisting of isocyanate and amino compounds. The polyurea coating has excellent mechanical property, has outstanding wear resistance, impact resistance, corrosion resistance, medium resistance, thermal stability and the like, is applied to the fields of corrosion resistance, water resistance, wear resistance, damping, protection, shock resistance and the like, has high construction efficiency, can reach millimeter level by one-time spraying, and greatly saves labor cost.

Although the performance of spray polyurea is widely appreciated, the application of the spray polyurea is limited to a certain extent by the characteristic of quick curing, the gel time of the early-used polyurea coating is only several seconds to ten seconds, the spray polyurea coating is not sufficiently wetted with a substrate, the required special spray equipment is complex, the price is high, the stability is not good, the maintenance is serious, and the application life of the polyurea is prolonged by researching an amino compound because the polyurea is obtained by reacting isocyanate and the amino compound.

At present, polyaspartic ester resin is proposed on the market as an amino compound component, an active hydrogen group in polyaspartic ester is a secondary amine group, and the reaction activity of polyaspartic ester polyurea is further reduced due to the steric hindrance effect of a proximal group, so that the reaction speed of polyaspartic ester polyurea is greatly reduced, the construction validity period is prolonged to a certain extent on the premise of ensuring the basic performance, but the raw material cost is generally higher. Therefore, it is necessary to provide a polyurea with low cost, long construction period and excellent performance and a synthesis method thereof.

Disclosure of Invention

In order to solve the above problems, the first aspect of the present invention provides a method for synthesizing a polyurea prepolymer, wherein the structural formula of the polyurea prepolymer is represented by formula (1):

R₁one or more selected from linear alkyl, cycloalkyl and alkyl ether;

R₂one or more selected from linear alkyl, cycloalkyl and aryl.

As a preferred embodiment of the present invention, R₁The number of carbon atoms is less than 20.

As a preferred embodiment of the present invention, R₂The number of carbon atoms is less than 10.

As a preferred technical scheme, the polyurea prepolymer is prepared from binary methacrylate and monoamine;

the structural formula of the binary methacrylate is shown as the formula (2):

the structural formula of the monoamine is R₂-NH₂。

In a preferred embodiment of the present invention, the molar ratio of the dimethacrylate to the monoamine is 1: (2.2-2.5).

As a preferred technical scheme, the preparation method of the polyurea prepolymer comprises the following steps:

and (3) dropwise adding monoamine into binary methacrylate, reacting at 50-80 ℃, and then carrying out reduced pressure distillation to obtain the polyurea prepolymer.

As a preferred technical scheme, the binary methacrylate is prepared from methacrylate and dihydric alcohol;

the structural formula of the methacrylate is shown as the formula (3):

r is alkyl;

the structural formula of the dihydric alcohol is HO-R₁-OH。

In a preferred embodiment of the present invention, the molar ratio of the diol to the methacrylate is 1: (4-6).

As a preferable technical scheme, the preparation method of the binary methacrylate comprises the following steps:

mixing dihydric alcohol, methacrylate, a catalyst and a polymerization inhibitor, reacting at 100-130 ℃, and distilling under reduced pressure to obtain the binary methacrylate.

The second aspect of the invention provides application of the synthesis method of the polyurea prepolymer to the synthesis of macromolecules.

Compared with the prior art, the invention has the following beneficial effects:

(1) compared with the common amine prepolymer, the synthesis method of the polyurea prepolymer has higher construction validity period when reacting with isocyanate by controlling the structure of the imino group of the polyurea prepolymer and the structure of the functional group connected with the imino group.

(2) The polyurea prepolymer prepared by the invention can be prepared into products with excellent mechanical properties by using conventional reaction raw materials such as monoamine, methacrylate, dihydric alcohol and the like, and compared with the asparagus polyurea, the cost can be reduced when the products have similar or better construction validity.

(3) The synthesis method provided by the invention is simple, has high yield and is convenient for mass production.

Detailed Description

The disclosure may be understood more readily by reference to the following detailed description of preferred embodiments of the invention and the examples included therein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control.

The term "prepared from …" as used herein is synonymous with "comprising". The terms "comprises," "comprising," "includes," "including," "has," "having," "contains," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

The conjunction "consisting of …" excludes any unspecified elements, steps or components. If used in a claim, the phrase is intended to claim as closed, meaning that it does not contain materials other than those described, except for the conventional impurities associated therewith. When the phrase "consisting of …" appears in a clause of the subject matter of the claims rather than immediately after the subject matter, it defines only the elements described in the clause; other elements are not excluded from the claims as a whole.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.

The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. "optional" or "any" means that the subsequently described event or events may or may not occur, and that the description includes instances where the event occurs and instances where it does not.

Approximating language, as used herein throughout the specification and claims, is intended to modify a quantity, such that the invention is not limited to the specific quantity, but includes portions that are literally received for modification without substantial change in the basic function to which the invention is related. Accordingly, the use of "about" to modify a numerical value means that the invention is not limited to the precise value. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. In the present description and claims, range limitations may be combined and/or interchanged, including all sub-ranges contained therein if not otherwise stated.

In addition, the indefinite articles "a" and "an" preceding an element or component of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be read to include one or at least one, and the singular form of an element or component also includes the plural unless the stated number clearly indicates that the singular form is intended.

The present invention is illustrated by the following specific embodiments, but is not limited to the specific examples given below.

The invention provides a synthesis method of a polyurea prepolymer, wherein the structural formula of the polyurea prepolymer is shown as the formula (1):

in one embodiment, R₁One or more selected from the group consisting of a straight chain alkyl group, a cycloalkyl group, an alkyl ether group, and examples of the straight chain alkyl group include, but are not limited to, methyl group, ethyl group, dodecyl group, and octadecyl group; examples of cycloalkyl groups include, but are not limited to, cyclohexyl, 2-methylcyclohexyl, 4' -dicyclohexyl, cyclopentyl; examples of alkyl ether groups include, but are not limited to, - (CH)₂CH₂O)_n-、-(CH₃CHCH₂O)_m-, n and m are integers. In a preferred embodiment, R₁The number of carbon atoms is less than 20.

In one embodiment, R₂One or more selected from linear alkyl, cycloalkyl and aryl as linear alkaneExamples of radicals, including but not limited to, methyl, ethyl, octyl; examples of cycloalkyl groups include, but are not limited to, cyclohexyl, 2-methylcyclohexyl, cyclopentyl; examples of aryl groups include, but are not limited to, phenyl, methylphenyl, ethylphenyl. In a preferred embodiment, R₂The number of carbon atoms is less than 10.

Applicants have found that by controlling R on both sides of an imino group₁And R₂The structure of (2) can regulate steric hindrance and electronic structure around imine group, so that the construction effective period of the prepolymer prepared by the invention can be prolonged, and excellent performance can be obtained, mainly because of proper R₁And R₂Provides certain steric hindrance, reduces the electron cloud density and the like of an imine group through the action of electron absorption and the like, thereby reducing the reaction activity, promoting the completion of crosslinking by isothermal and reaction with isocyanate and ensuring the R with a certain chain length₁And R₂The structure is favorable for the increase of the external force resistance of the cured polymer, thereby obtaining good performance, and compared with the asparagus polyurea resin, the material cost is greatly reduced.

Polyurea prepolymer

In one embodiment, the polyurea prepolymer is prepared from binary methacrylate and monoamine;

the structural formula of the binary methacrylate is shown as the formula (2):

the structural formula of the monoamine is R₂-NH₂。

Preferably, the molar ratio of the binary methacrylate to the monoamine according to the invention is 1: (2.2 to 2.5) and there may be mentioned, for example, 1: 2.2, 1: 2.25, 1: 2.3, 1: 2.35, 1: 2.4, 1: 2.45, 1: 2.5.

the polyurea prepolymer can be prepared by the reaction of the amino group of the monoamine and the unsaturated double bond in the binary methacrylate, the reaction of the binary methacrylate is promoted to be complete by adding excessive monoamine, wherein the reaction end point can be detected by gas chromatography, the reaction time is about 7 hours generally, after the reaction is finished, unreacted raw materials can be removed by reduced pressure distillation, and the yield can reach more than 85 percent. More preferably, the preparation method of the polyurea prepolymer of the invention comprises the following steps:

and (3) dropwise adding monoamine into binary methacrylate, reacting at 50-80 ℃, and then carrying out reduced pressure distillation to obtain the polyurea prepolymer.

Further preferably, the preparation method of the polyurea prepolymer comprises the following steps:

and (3) dropwise adding monoamine into binary methacrylate, reacting at 50-80 ℃, and then carrying out reduced pressure distillation to obtain the polyurea prepolymer.

The amine and unsaturated double bond generally need basic catalyst for catalysis, and the basic catalyst is also added in the process of preparing the binary methacrylate, so the catalyst can be added or not added in the reaction process of the binary methacrylate and the monoamine. Still more preferably, the preparation method of the polyurea prepolymer of the invention comprises the following steps:

and (3) dropwise adding monoamine into a mixture of binary methacrylate and the first catalyst, reacting at 50-80 ℃, and then carrying out reduced pressure distillation to obtain the polyurea prepolymer.

In the present invention, although the catalyst is not particularly limited, dibutyltin oxide and K are exemplified₂CO₃Basic catalysts such as Amberlyst15 and sodium hydroxide; in one embodiment, the first catalyst accounts for 0 to 5 wt% of the binary methacrylate.

Binary methacrylate

In one embodiment, the binary methacrylate of the present invention is prepared from a methacrylate and a glycol;

the structural formula of the methacrylate is shown as the formula (3):

r is alkyl;

the structural formula of the dihydric alcohol is HO-R₁-OH。

In view of raw material cost and reactivity considerations, applicants have found that it is possible to select a methacrylate of suitable chain length, in one embodiment, R is an alkyl group; preferred are C1-C5 alkyl groups, more preferred are C1 alkyl groups.

In order to complete the reaction of the diols, the applicants have found that it is necessary to use an excess of methacrylate. Preferably, the molar ratio of the diol and the methacrylate in the present invention is 1: (4 to 6), there may be mentioned, 1: 4. 1: 4.5, 1: 5. 1: 5.5, 1: 6.

the applicant finds that the binary methacrylate is obtained by reacting two hydroxyl groups of dihydric alcohol with an ester group of methacrylate under the action of a catalyst to perform ester exchange, attaching two methacrylates to the dihydric alcohol, monitoring the completion of the reaction by gas chromatography, and removing unreacted raw materials by reduced pressure distillation after the reaction is completed. More preferably, the method for preparing the binary methacrylate of the present invention comprises:

mixing dihydric alcohol, methacrylate, a catalyst and a polymerization inhibitor, reacting at 100-130 ℃, and distilling under reduced pressure to obtain the binary methacrylate.

Examples of catalysts include, but are not limited to, dibutyltin oxide, K₂CO₃Amberlyst 15. In one embodiment, the catalyst is 2 to 5 wt% of the glycol.

Examples of polymerization inhibitors include, but are not limited to, p-hydroxyanisole, hydroquinone, copper sulfate pentahydrate, cuprous chloride, p-tert-butylphenol, p-tert-butylcatechol. In one embodiment, the polymerization inhibitor accounts for 1 to 3 wt% of the glycol.

Further preferably, the preparation method of the binary methacrylate comprises the following steps:

mixing dihydric alcohol, methacrylate, a catalyst and a polymerization inhibitor, introducing air, reacting at 100-130 ℃, and distilling under reduced pressure to obtain the binary methacrylate.

In order to improve the efficiency of distillation and rectification, the applicant inserts a rectification column into a container of dihydric alcohol, methacrylate, a catalyst and a polymerization inhibitor, such as a bottle mouth of a four-necked bottle, arranges a reflux distributor above the rectification column, and arranges a filler inside the rectification column.

The second aspect of the present invention provides the use of the method for synthesizing a polyurea polymer as described above for the synthesis of polymers, and there may be mentioned polymers in which an amino group such as a polyurea polymer and a phenol resin participates in the reaction.

Examples

The present invention will be specifically described below by way of examples. It should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and that the insubstantial modifications and adaptations of the present invention by those skilled in the art based on the above disclosure are still within the scope of the present invention.

Example 1

The embodiment provides a synthesis method of a polyurea prepolymer, which comprises the following steps:

(1) respectively adding 24.8g of ethylene glycol, 240g of methyl methacrylate, 1.91g of dibutyltin oxide (catalyst) and 0.85g of p-hydroxyanisole (polymerization inhibitor) into a 500ml four-necked bottle, connecting a rectification column to one side of the four-necked bottle, mounting a reflux distributor on a column head, filling Raschig rings in the column, introducing air to the other side of the four-necked bottle, magnetically stirring at 105 ℃, reacting for about 6 hours, and detecting whether the reaction is finished by using gas chromatography; after the reaction is finished, removing unreacted raw materials by reduced pressure distillation to obtain a target product X₁。

(2) Fetch 73g X₁Slowly adding 52.2g of tert-butylamine into X1 in a 250ml four-necked bottle through a constant pressure funnel, mechanically stirring at 80 ℃, reacting for more than 7 days, determining the reaction end point through gas chromatography and amine value measurement, completing the reaction, removing unreacted raw materials through reduced pressure distillation to obtain a target product Y₁The yield thereof was found to be 92.3%.

Example 2

The embodiment provides a synthesis method of a polyurea prepolymer, which comprises the following steps:

(1) into a 500ml four-necked flask were charged 42.5g of ethylene glycol, 200g of methyl methacrylate and 2.02g K₂CO₃(catalyst) and 0.85g p-hydroxyanisole (inhibitor); introducing a rectification column on one side of a four-necked bottle, installing a reflux distributor on the head of the four-necked bottle, introducing air into the column by using a Raschig ring as a filler, magnetically stirring at 110 ℃, reacting for about 6 hours, and detecting whether the reaction is finished by using gas chromatography; after the reaction is finished, removing unreacted raw materials by reduced pressure distillation to obtain a target product X₂；

(2) Take 67.6g X₂In a 250ml four-necked bottle, 59.4g of 2-methylcyclohexylamine is slowly added into X2 through a constant pressure funnel in a dropwise manner, mechanical stirring is carried out at 80 ℃, the reaction lasts for more than 7 days, and the reaction end point is determined by gas chromatography and amine value measurement; after the reaction is finished, the unreacted raw materials are removed by reduced pressure distillation to obtain a target product Y₂(ii) a The yield thereof was found to be 96.6%.

Example 3

The embodiment provides a synthesis method of a polyurea prepolymer, which comprises the following steps:

(1) 80g of PEG200, 160g of methyl methacrylate and 2.52g K were added to a 500ml four-necked flask₂CO₃(catalyst) and 1.28g p-hydroxyanisole (inhibitor); introducing a rectification column on one side of a four-necked bottle, installing a reflux distributor on the head of the four-necked bottle, introducing air into the column by using a Raschig ring as a filler, magnetically stirring at 115 ℃ for about 6 hours, and detecting whether the reaction is finished by using gas chromatography; after the reaction is finished, removing unreacted raw materials by reduced pressure distillation to obtain a target product X₃；

(2) Take 78.3g X₃Slowly adding 46.9g of cyclohexylamine into X3 in a 250ml four-necked bottle through a constant pressure funnel, mechanically stirring at 80 ℃, reacting for more than 7 days, and determining the reaction end point through gas chromatography and amine value measurement; after the reaction is finished, the unreacted raw materials are removed by reduced pressure distillation to obtain a target product Y₃(ii) a The yield thereof was found to be 89.9%.

Example 4

The embodiment provides a synthesis method of a polyurea prepolymer, which comprises the following steps:

(1) into a 500ml four-necked flask were charged 4,4' -dihydroxybicyclohexane (75.6 g), methylmethacrylate (175 g), Amberlyst (2.4 g) 15 ion exchange resin (catalyst) and p-hydroxyanisole (polymerization inhibitor) (0.85 g), respectively; introducing a rectification column on one side of a four-necked bottle, installing a reflux distributor on the head of the four-necked bottle, introducing air into the column by using a Raschig ring as a filler, magnetically stirring at 120 ℃ for about 7 hours, and detecting whether the reaction is finished by using gas chromatography; after the reaction is finished, removing unreacted raw materials by reduced pressure distillation to obtain a target product X₄；

(2) Take 73.5g X₄Slowly dropping 52.2g of aniline into X4 through a constant pressure funnel in a 250ml four-necked bottle, mechanically stirring at 80 ℃, reacting for more than 7 days, and determining the reaction end point through gas chromatography and amine value measurement; after the reaction is finished, the unreacted raw materials are removed by reduced pressure distillation to obtain a target product Y₄(ii) a The yield thereof was found to be 86.8%.

Example 5

The embodiment provides a synthesis method of a polyurea prepolymer, which comprises the following steps:

(1) respectively adding 1g, 12-dodecanediol, 307.21g of propyl methacrylate, 1.91g of dibutyltin oxide (catalyst) and 0.85g of p-hydroxyanisole (polymerization inhibitor) into a 500ml four-necked bottle, connecting a rectification column to one side of the four-necked bottle, mounting a reflux distributor on a column head, introducing air to the other side of the four-necked bottle, magnetically stirring at 150 ℃, reacting for about 6 hours, and detecting whether the reaction is finished by gas chromatography; after the reaction was completed, it was removed by distillation under reduced pressureUnreacted raw materials to obtain a target product X₅。

(2) Fetch 73g X₅Slowly adding 52.2g of tert-butylamine into X1 in a 250ml four-necked bottle through a constant pressure funnel, mechanically stirring at 80 ℃, reacting for more than 7 days, determining the reaction end point through gas chromatography and amine value measurement, completing the reaction, removing unreacted raw materials through reduced pressure distillation to obtain a target product Y₅The yield thereof was found to be 81.1%.

Evaluation of Performance

Polyurea prepolymer Y provided in the example₁、Y₂、Y₃、Y₄、Y₅And a control group F420 (from Feiyang Jun research New Material Co., Ltd.) as a component B, mixing the component B with a component A-HDI tripolymer at a mixing ratio of 1:1.2, and mixing A, B to obtain polyurea A₁B₁、A₂B₂、A₃B₃、A₄B₄、A₅B₅、A₀B₀The measured properties are shown in table 1.

Table 1 performance characterization test

As can be seen from the test results in Table 1, the polyurea synthesized by the polyurea prepolymer prepared by the invention can obviously prolong the construction effective period, and the cost is greatly saved by synthesizing the polyurea prepolymer by using cheap and easily available raw materials on the premise of ensuring the basic performance.

The foregoing examples are merely illustrative and serve to explain some of the features of the method of the present invention. The appended claims are intended to claim as broad a scope as is contemplated, and the examples presented herein are merely illustrative of selected implementations in accordance with all possible combinations of examples. Accordingly, it is applicants' intention that the appended claims are not to be limited by the choice of examples illustrating features of the invention. Also, where numerical ranges are used in the claims, subranges therein are included, and variations in these ranges are also to be construed as possible being covered by the appended claims.