阅读说明：本技术 一种橘皮精油基聚酰胺活性单体及其制备方法 (Orange peel essential oil based polyamide active monomer and preparation method thereof ) 是由 李守海 刘芮同 李梅 丁海阳 许利娜 姚娜 杨小华 张燕 于 2020-12-18 设计创作，主要内容包括：一种橘皮精油基聚酰胺活性单体及其制备方法,将一定量的橘皮精油与不饱和酸或酸酐反应得到橘皮精油基不饱和酸或酸酐共聚物；然后将制得的橘皮精油基不饱和酸或酸酐共聚物与小分子多胺进行酰胺化反应,得到橘皮精油基聚酰胺活性单体。本专利制备的橘皮精油基聚酰胺活性单体可作为环氧树脂的聚酰胺固化剂,相比传统的聚酰胺固化剂挥发性小、几乎无毒,提高了与环氧树脂固化反应时的反应活性,固化后的树脂具有较好的力学强度和热稳定性能。橘皮精油基聚酰胺活性单体的制备原料来源丰富,价格低廉,同时也属于天然环保的可再生资源。本发明的制备工艺路线简单,反应温和,应用前景广阔。(An orange peel essential oil based polyamide active monomer and a preparation method thereof are disclosed, wherein a certain amount of orange peel essential oil reacts with unsaturated acid or anhydride to obtain an orange peel essential oil based unsaturated acid or anhydride copolymer; and then carrying out amidation reaction on the prepared orange peel essential oil based unsaturated acid or anhydride copolymer and micromolecular polyamine to obtain the orange peel essential oil based polyamide active monomer. The orange peel essential oil based polyamide active monomer prepared by the patent can be used as a polyamide curing agent of epoxy resin, is small in volatility and almost non-toxic compared with a traditional polyamide curing agent, improves the reactivity during the curing reaction with the epoxy resin, and the cured resin has better mechanical strength and thermal stability. The orange peel essential oil based polyamide active monomer is rich in raw material source and low in price, and belongs to a natural environment-friendly renewable resource. The preparation process has the advantages of simple route, mild reaction and wide application prospect.)

1. A preparation method of an orange peel essential oil based polyamide active monomer is characterized by comprising the following steps: the first step is as follows: adding unsaturated acid or anhydride into a reactor, heating to 45-70 ℃, dropwise adding orange peel essential oil, wherein the molar ratio of the orange peel essential oil to the unsaturated acid or anhydride is (1.2-2.0): 1, adding a catalyst accounting for 0.056-0.6% of the total mass of reactants, heating to 170-190 ℃, maintaining the temperature, reacting for 2-2.5 hours, cooling to 80-100 ℃, and carrying out reduced pressure distillation to remove unreacted orange peel essential oil, unsaturated acid and other byproducts, thereby obtaining an intermediate product, namely an orange peel essential oil-based unsaturated acid or anhydride copolymer; the second step is that: adding the orange peel essential oil-based unsaturated acid or anhydride copolymer prepared in the first step into a reactor, heating to 50-60 ℃, and reacting at N₂And (2) adding polyamine dropwise under the atmosphere, wherein the molar ratio of carbonyl of the orange peel essential oil based unsaturated acid or anhydride copolymer to the polyamine is 1 (1.2-1.4), after the dropwise addition is finished, heating to 140-150 ℃, refluxing and maintaining for 2-2.5 h, then heating to 190-210 ℃, maintaining for 2h, carrying out reduced pressure distillation for 0.5-1 h under 0.67-1.33 kPa, stopping heating after no free micromolecule amine is evaporated, and cooling to room temperature to obtain the orange peel essential oil based polyamide active monomer.

2. The method for preparing orange peel essential oil based polyamide active monomer according to claim 1, wherein the unsaturated acid or anhydride is crotonic acid, maleic anhydride or trans-maleic anhydride.

3. The method for preparing orange peel essential oil based polyamide active monomer according to claim 1, wherein the catalyst is iodine or phosphoric acid.

4. The method for preparing orange peel essential oil based polyamide active monomer according to claim 1, wherein the selected polyamine is ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine or diethylaminopropylamine.

5. Orange peel essential oil based polyamide reactive monomer obtainable by the process according to any one of claims 1 to 4.

Technical Field

The invention belongs to the technical field of polyamide active monomers, and particularly relates to an orange peel essential oil based polyamide active monomer and a preparation method thereof.

Background

The epoxy resin as a thermosetting resin has excellent electrical insulation, heat resistance, adhesion and other properties, can obtain good processability and operability after being cured by a curing agent, and is widely applied to the fields of chemical metallurgy, buildings, medical composite materials and the like. Polyamide resins are often used as curing agents for epoxy resins, and a common synthetic process for polyamide resins is to react a linoleic acid dimer, a eleostearic acid dimer, etc. with aliphatic polyamines such as ethylenediamine, diethylenetriamine, triethylenetetramine, etc., and the obtained polyamide is generally an amber viscous liquid. The epoxy resin solidified by polyamide as the curing agent has the characteristics of high crosslinking density, good heat resistance and the like.

The common polyamide curing agent at present has long curing time, high toxicity and low reaction activity, and the resin cured product is easy to have yellowing and chalking phenomena under the photooxidation action of outdoor light and atmosphere. In addition, common aliphatic amines such as ethylenediamine, diethylenetriamine, triethylenetetramine, diethylaminopropylamine and the like are volatile and irritant, and are harmful to human bodies after long-term use, and a series of synthetic reactions are required to be carried out on small-molecular active amines to modify the small-molecular active amines so as to reduce the irritation of the small-molecular active amines. Meanwhile, with the increasing exhaustion of petroleum resources and the increasing severity of environmental pollution, the search for high-quality, cheap and renewable petroleum substitutes becomes a hotspot and development trend in the field of scientific research in the world nowadays.

The orange peel essential oil is an environment-friendly natural product extracted from orange peel, has the advantages of rich source, no toxicity, environmental protection, pleasant aroma and the like, and is widely applied to the industries of chemical industry, agriculture, food, cosmetics and the like. The orange peel essential oil contains a large amount of unsaturated double bonds, and can perform chemical reactions such as hydrogenation, oxidation, isomerization, sulfation, sulfonation, polymerization, pyrolysis and the like. The orange peel essential oil can be used as a substitute of a toxic solvent, for example, the orange peel essential oil can replace dimethylbenzene to be used for natural resin and synthetic resin, and can also be used as various coatings, paint products, diluents or additives, so that the content of toxic and harmful substances in the orange peel essential oil can be greatly reduced, and the requirement of environmental protection is met. The novel orange peel essential oil based polyamide has important significance in developing orange peel essential oil based polyamide active monomers capable of being used as epoxy resin curing agents by utilizing the natural and environment-friendly characteristics of orange peel essential oil at present when a sustainable development road is emphasized.

Disclosure of Invention

The technical problem to be solved is as follows: the invention provides an orange peel essential oil based polyamide active monomer and a preparation method thereof. Compared with the traditional amine curing agent, the product of the invention has small volatility and almost no toxicity, improves the reaction activity during the curing reaction with the epoxy resin, and the cured resin has better mechanical strength and thermal property. The orange peel essential oil based polyamide active monomer is rich in raw material source and low in price, and belongs to a natural environment-friendly renewable resource. The preparation process has the advantages of simple route, mild reaction and certain utilization value.

The technical scheme is as follows: a preparation method of an orange peel essential oil based polyamide active monomer comprises the following steps: the first step is as follows: adding unsaturated acid or anhydride into a reactor, heating to 45-70 ℃, dropwise adding orange peel essential oil, wherein the molar ratio of the orange peel essential oil to the unsaturated acid or anhydride is (1.2-2.0): 1, adding a catalyst accounting for 0.056-0.6% of the total mass of reactants, and adding a catalyst accounting for 0.056-0.6% of the total mass of the reactantsHeating to 170-190 ℃, maintaining the temperature, reacting for 2-2.5 h, cooling to 80-100 ℃, and distilling under reduced pressure to remove unreacted orange peel essential oil, unsaturated acid and other byproducts to obtain an intermediate orange peel essential oil-based unsaturated acid or anhydride copolymer; the second step is that: adding the orange peel essential oil-based unsaturated acid or anhydride copolymer prepared in the first step into a reactor, heating to 50-60 ℃, and reacting at N₂And (2) adding polyamine dropwise under the atmosphere, wherein the molar ratio of carbonyl of the orange peel essential oil based unsaturated acid or anhydride copolymer to the polyamine is 1 (1.2-1.4), after the dropwise addition is finished, heating to 140-150 ℃, refluxing and maintaining for 2-2.5 h, then heating to 190-210 ℃, maintaining for 2h, carrying out reduced pressure distillation for 0.5-1 h under 0.67-1.33 kPa, stopping heating after no free micromolecule amine is evaporated, and cooling to room temperature to obtain the orange peel essential oil based polyamide active monomer.

The unsaturated acid or anhydride is crotonic acid, maleic anhydride or trans-maleic anhydride.

The catalyst is iodine or phosphoric acid.

The polyamine is ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine or diethylaminopropylamine.

The orange peel essential oil based polyamide active monomer prepared by the preparation method.

Has the advantages that: (1) compared with the traditional amine curing agent, the orange peel essential oil based polyamide active monomer prepared by the invention utilizes orange peel essential oil which has rich sources and low price, belongs to natural and environment-friendly renewable resources, and gets rid of dependence on petrochemical resources to a certain extent. (2) Compared with the traditional amine curing agent, the orange peel essential oil based polyamide curing agent is introduced, has small volatility and almost no toxicity, can improve the reaction activity during the curing reaction with epoxy resin, and the cured resin has better mechanical strength and thermal property. (3) The preparation process has the advantages of simple route, mild reaction, stable property of the prepared product and certain utilization value.

Drawings

FIG. 1 is an infrared spectrum of an orange peel essential oil based polyamide reactive monomer of example 2, using an orange peel essential oil based maleic anhydride copolymer and diethylenetriamineThe polyamide obtained is at 3288 and 1119cm^-1Respectively shows an N-H characteristic absorption peak of aliphatic polyamine and a C-N stretching vibration absorption peak of aliphatic amine, 1651 and 1556cm^-1And a secondary amide association state C = O stretching vibration absorption peak and a secondary amide association state N-H in-plane bending vibration absorption peak are respectively shown, which indicates that the orange peel essential oil based polyamide active monomer is successfully prepared.

Detailed Description

The invention is further illustrated by the following examples:

example 1

Adding crotonic acid into a reactor with a stirring device, heating to 70 deg.C to make crotonic acid in molten state, adding pericarpium Citri Tangerinae essential oil dropwise at molar ratio of pericarpium Citri Tangerinae essential oil to crotonic acid of 2:1, and adding I with total mass of 0.056%₂Heating to 180 ℃, keeping the temperature at 180 ℃ for reaction for 2h, cooling to 100 ℃, and carrying out reduced pressure distillation to remove unreacted orange peel essential oil, crotonic acid and a small amount of other byproducts, thereby obtaining the orange peel essential oil crotonic acid copolymer. Adding the copolymer of the essential oil of orange peel and the crotonic acid into a reactor, heating to 60 ℃, and keeping the temperature at N₂And (2) dropwise adding ethylenediamine under the environment, wherein the molar ratio of carbonyl in the orange peel essential oil butenoic acid copolymer to the amino of ethylenediamine is 1:1.2, after dropwise adding, heating to 150 ℃, refluxing and maintaining for 2h, then heating to 200 ℃, maintaining for 2h, then carrying out reduced pressure distillation for 1h under 0.67kPa, stopping heating after no free amine is distilled out, and cooling to room temperature to obtain the orange peel essential oil based polyamide active monomer.

Example 2

Adding maleic anhydride into a reactor with a stirring device, heating to 60 ℃ to enable the maleic anhydride to be in a molten state, dropwise adding orange peel essential oil, wherein the molar ratio of the orange peel essential oil to the maleic anhydride is 1.5:1, adding phosphoric acid with the total mass of 0.06%, heating to 180 ℃, maintaining the temperature at 180 ℃ for reaction for 2 hours, then cooling to 100 ℃, adding powdery calcium hydroxide with the total mass of 0.06%, reacting for 10 minutes, and then carrying out reduced pressure distillation to remove unreacted orange peel essential oil, maleic anhydride and a small amount of other byproducts, thus obtaining the orange peel essential oil maleic anhydride copolymer. Adding the orange peel essential oil maleic anhydride copolymer into a reactor, heating to 60 ℃, and keeping the temperature at N₂Drip under the environmentAdding diethylenetriamine, wherein the molar ratio of carbonyl in the orange peel essential oil maleic anhydride copolymer to amino in diethylenetriamine is 1:1.4, heating to 140 ℃ after dropwise adding is finished, refluxing and keeping for 2h, then heating to 200 ℃ for 2h, carrying out reduced pressure distillation for 1h under 1.33kPa, stopping heating after no free amine is evaporated, and cooling to room temperature to obtain the orange peel essential oil based polyamide active monomer.

Example 3

Adding trans-butenedioic anhydride into a reactor with a stirring device, heating to 60 ℃, enabling the trans-butenedioic anhydride to be in a molten state, dropwise adding orange peel essential oil, wherein the molar ratio of the orange peel essential oil to the trans-butenedioic anhydride is 1.5:1, adding phosphoric acid with the total mass of 0.06%, heating to 180 ℃, maintaining the temperature at 180 ℃, reacting for 2.5 hours, cooling to 80 ℃, adding powdery calcium hydroxide with the total mass of 0.06%, reacting for 10 minutes, and performing reduced pressure distillation to remove unreacted orange peel essential oil, the trans-butenedioic anhydride and a small amount of other byproducts, thereby obtaining the trans-butenedioic anhydride copolymer of the orange peel essential oil. Adding the orange peel essential oil trans-butenedioic anhydride copolymer into a reactor, heating to 50 ℃, and reacting at N₂Dropwise adding triethylene tetramine under the environment, wherein the molar ratio of carbonyl in the orange peel essential oil trans-butenedioic anhydride copolymer to amino in the triethylene tetramine is 1:1.2, heating to 140 ℃ after dropwise adding, refluxing and keeping for 2.5h, then heating to 190 ℃, keeping for 2h, then carrying out reduced pressure distillation for 1h under 1.33kPa, stopping heating after no free amine is evaporated, and cooling to room temperature to obtain the orange peel essential oil based polyamide active monomer.

Example 4

Adding maleic anhydride into a reactor with a stirring device, heating to 60 ℃, dropwise adding orange peel essential oil, wherein the molar ratio of the orange peel essential oil to the maleic anhydride is 1.5:1, adding phosphoric acid accounting for 0.06% of the total mass, heating to 180 ℃, maintaining 180 ℃, reacting for 2 hours, cooling to 100 ℃, adding powdery calcium hydroxide accounting for 0.06% of the total mass, reacting for 10 minutes, and distilling under reduced pressure to remove unreacted orange peel essential oil, maleic anhydride and a small amount of other byproducts, thus obtaining the orange peel essential oil-maleic anhydride copolymer. Adding the orange peel essential oil maleic anhydride copolymer into a reactor, heating to 60 ℃, and keeping the temperature at N₂Dripping tetraethylenepentamine and orange peel essential oil under the environmentThe mol ratio of carbonyl in the maleic anhydride copolymer to amino in tetraethylenepentamine is 1:1.4, after the dripping is finished, the temperature is raised to 150 ℃, the reflux is carried out and the reflux is kept for 2 hours, then the temperature is raised to 210 ℃, the reduced pressure distillation is carried out for 1 hour under 1.33kPa after the reflux is kept for 2 hours, the heating is stopped after no free amine is distilled out, and the temperature is cooled to the room temperature, so that the orange peel essential oil based polyamide active monomer is obtained.

Example 5

Adding fumaric anhydride into a reactor with a stirring device, heating to 60 ℃, enabling the fumaric anhydride to be in a molten state, dropwise adding orange peel essential oil, enabling the molar ratio of the orange peel essential oil to the fumaric anhydride to be 1.5:1, adding phosphoric acid with the total mass of 0.06%, heating to 170 ℃, maintaining the temperature at 180 ℃, reacting for 2 hours, cooling to 100 ℃, adding powdery calcium hydroxide with the total mass of 0.06%, reacting for 10 minutes, and performing reduced pressure distillation to remove unreacted orange peel essential oil, the fumaric anhydride and a small amount of other byproducts, thereby obtaining the fumaric anhydride copolymer of the orange peel essential oil. Adding the orange peel essential oil fumaric anhydride copolymer into a reactor, heating to 60 ℃, and reacting at N₂Dropwise adding tetramethylethylenediamine under the environment, wherein the molar ratio of carbonyl in the orange peel essential oil fumaric anhydride copolymer to amino of the tetramethylethylenediamine is 1:1.2, heating to 150 ℃ after dropwise adding, refluxing and keeping for 2.5h, then heating to 210 ℃, keeping for 2h, carrying out reduced pressure distillation for 1h under 0.67kPa, stopping heating after no free amine is distilled out, and cooling to room temperature to obtain the orange peel essential oil based polyamide active monomer.

Comparative example:

experimental group 1: 67.9g of the orange peel essential oil based polyamide active monomer prepared in the example 2 is accurately weighed, then 100.0g E51 is added, after uniform mixing, the sample is poured into a mold, firstly the sample is placed for a few minutes to eliminate bubbles, then precured for 3h at the temperature of 45 ℃, and then cured for 8h at the temperature of 100 ℃.

Experimental group 2: 53.3g of the orange peel essential oil based polyamide active monomer prepared in the example 3 is accurately weighed, then 100.0g E51 is added, after uniform mixing, the sample is poured into a mold, firstly the sample is placed for a few minutes to eliminate bubbles, then precured for 3h at the temperature of 45 ℃, and then cured for 8h at the temperature of 100 ℃.

The mechanical properties of the two thermosetting materials were analyzed, and the measurement results are shown in table 1.

TABLE 1 random comparison of thermal curing Performance for each experimental group

Note: the tensile property of the cured sample strip is tested according to GB/T1040.3-2006, the hardness is tested according to a Shore hardness test method GB/T2411-2008, the gel content is measured by an acetone solvent Soxhlet extraction method (see a paper: Zhao Xueyi. Soxhlet extraction method for measuring the gel content [ J ] of the high oil-absorbing resin; Gansu environmental research and monitoring: 2001, No. 04), and the glass transition temperature is measured by a dynamic thermal mechanical analysis method (ASTM D7028-2007).