阅读说明：本技术 一种植物油基耐寒增塑剂的制备方法及其应用 (Preparation method and application of plant oil-based cold-resistant plasticizer ) 是由 蒋平平 刘德开 聂志欣 代注顶 王涵颖 于 2020-07-10 设计创作，主要内容包括：一种植物油基耐寒增塑剂的制备方法及其应用,属于精细化学品合成、功能新材料助剂及塑料助剂应用领域。本发明使用油酸、1,4-环己烷二甲醇和过氧化氢为主要原料,通过酯化反应制备得到1,4-环己烷二甲醇二油酸酯,再通过环氧化反应得到植物油基耐寒增塑剂环氧1,4-环己烷二甲醇二油酸酯。本发明制备的环氧1,4-环己烷二甲醇二油酸酯增塑剂颜色浅,粘度低,与PVC的相容性好,与对苯二甲酸二(2-乙基已)酯(DOTP)相比,它应用在PVC中具有相似的拉伸性能,更优异的耐溶剂性、耐热性和耐寒性。(A preparation method and application of a vegetable oil-based cold-resistant plasticizer belong to the field of fine chemical synthesis, functional new material additives and plastic additive application. According to the invention, oleic acid, 1, 4-cyclohexanedimethanol and hydrogen peroxide are used as main raw materials, 1, 4-cyclohexanedimethanol dioleate is prepared through an esterification reaction, and then the vegetable oil-based cold-resistant plasticizer epoxy 1, 4-cyclohexanedimethanol dioleate is obtained through an epoxidation reaction. The epoxy 1, 4-cyclohexanedimethanol dioleate plasticizer prepared by the invention has light color, low viscosity and good compatibility with PVC, and compared with bis (2-ethyl hexyl) terephthalate (DOTP), the epoxy 1, 4-cyclohexanedimethanol dioleate plasticizer has similar tensile property, more excellent solvent resistance, heat resistance and cold resistance when being applied to PVC.)

1. A preparation method of a vegetable oil-based cold-resistant plasticizer is characterized by comprising the following steps: the epoxy 1, 4-cyclohexanedimethanol dioleate plasticizer is obtained by using oleic acid, 1, 4-cyclohexanedimethanol and hydrogen peroxide as main raw materials through two steps of reactions of esterification and epoxidation, and comprises the following specific steps:

(1) esterification reaction: adding oleic acid and 1, 4-cyclohexanedimethanol into a reactor, introducing nitrogen, and heating for reaction; adding the catalyst 1 when the temperature rises to a certain temperature, and then raising the temperature to continue the reaction; adding sodium hydroxide solution after the catalytic reaction is finished, and heating for reaction; centrifuging after the reaction is finished, taking supernate, washing the supernate to be neutral by using deionized water, and then removing residual water by vacuum distillation to obtain a product 1, 4-cyclohexanedimethanol dioleate;

(2) epoxidation reaction: adding the 1, 4-cyclohexanedimethanol dioleate prepared in the step (1) and a catalyst 2 into a reactor, gradually dropwise adding a mixture of formic acid and hydrogen peroxide, and heating for reaction; and (3) after the reaction is finished, washing the mixture to be neutral by using deionized water, and then removing residual water by vacuum distillation to obtain the final product, namely the plant oil-based cold-resistant plasticizer: epoxy 1, 4-cyclohexanedimethanol dioleate.

2. The preparation method of the vegetable oil-based cold-resistant plasticizer according to claim 1, which is characterized in that: the catalyst 1 in the esterification reaction in the step (1) is tetrabutyl titanate.

3. The preparation method of the vegetable oil-based cold-resistant plasticizer according to claim 1, which is characterized in that: in the esterification reaction in the step (1), 1, 4-cyclohexanedimethanol is used as a raw material: the mol ratio of the oleic acid is 1: 1-3; introducing nitrogen for 5-30 min before heating, wherein the mass of the catalyst 1 is 0.1-0.5% of the total mass of the raw materials, heating to 120-150 ℃, adding the catalyst 1, heating to 130-180 ℃, and continuing to react for 2-9 h; and adding 15-25% by mass of sodium hydroxide solution after the catalytic reaction is finished, heating to 30-70 ℃, and reacting for 0.1-3 h.

4. The preparation method of the vegetable oil-based cold-resistant plasticizer according to claim 3, wherein the sodium hydroxide quality used for preparing the sodium hydroxide solution in the step (1) is calculated according to the acid value of the solution at the end of the catalytic reaction, and according to the following formula, m = 7.13 × 10^-4× AV × Q + Q × 25%, wherein m is the mass of NaOH, AV is the acid value of the solution at the end of the catalytic reaction, and Q is the addition amount of oleic acid.

5. The preparation method of the vegetable oil-based cold-resistant plasticizer according to claim 1, which is characterized in that: in the step (1), the vacuum degree of vacuum distillation is-0.1 MPa, and distillation is carried out for 0.5-2 h at the temperature of 60-80 ℃.

6. The preparation method of the vegetable oil-based cold-resistant plasticizer according to claim 1, which is characterized in that: in the epoxidation reaction in the step (2), the catalyst 2 is a strong acid type cation exchange resin.

7. The preparation method of the vegetable oil-based cold-resistant plasticizer according to claim 1, which is characterized in that: in the epoxidation reaction in the step (2), the mass fraction of the hydrogen peroxide solution is 30-50%, and the molar ratio of 1, 4-cyclohexanedimethanol dioleate to formic acid to hydrogen peroxide is 1: 1-3: 8-15, wherein the mass of the catalyst 2 is 3-10% of the total mass; and during heating reaction, the temperature is 40-80 ℃, and the reaction time is 4-8 h.

8. The preparation method of the vegetable oil-based cold-resistant plasticizer according to claim 1, which is characterized in that: in the step (2), the vacuum degree in vacuum distillation is-0.1 MPa, and the distillation is carried out for 0.5-2 h at the temperature of 60-80 ℃.

9. Use of a vegetable oil-based cold-resistant plasticizer prepared by the method of any one of claims 1 to 8, wherein: the prepared epoxy 1, 4-cyclohexanedimethanol dioleate is used as a main plasticizer or an auxiliary plasticizer to be applied to the preparation of PVC resin.

Technical Field

The invention relates to a preparation method and application of a plant oil-based cold-resistant plasticizer, belonging to the field of fine chemical synthesis, new functional material additives and plastic additive application.

Background

PVC is widely applied to various fields as an important engineering plastic. Due to the hard and brittle nature of pure PVC, a certain amount of plasticizer is often added to the PVC to lower the glass transition temperature and improve its processability. At present, common phthalate plasticizers are easy to migrate out of products, so that the common phthalate plasticizers are easy to threaten human health, are forbidden to be used in a plurality of fields by the European Union, and are gradually limited to be used in China at present. With the increasing strictness of environmental requirements, there is a need to find a sustainable environment-friendly plasticizer to replace the conventional phthalate plasticizer.

The currently commonly used plasticizer dioctyl phthalate (DOP) is usually used at the temperature of more than 0 ℃, and the commonly used cold-resistant plasticizers DOA and DOS can only be used as auxiliary plasticizers due to the defects of poor compatibility and easy migration with PVC, and can only be mixed with a main plasticizer such as DOP and the like for use, so that the application of the plasticizer dioctyl phthalate (DOP) is greatly limited. In winter, in alpine regions around the world, including large regions in China, the temperature is below 0 ℃, the requirements of the regions on plastic products are continuously increased, and in a low-temperature environment, the selection of the plasticizer is extremely limited, so that the development of the cold-resistant plasticizer has great practicability.

Oleic acid is a monounsaturated fatty acid, which is a vegetable oil-based raw material. Meanwhile, the plasticizer is mainly from the nature, is a renewable biomass raw material, is non-toxic and harmless to the human body, is used as a raw material of the plasticizer, and accords with the concept of environmental friendliness. In addition, the fatty chain of the oleic acid contains unsaturated double bonds, so that the modification of the oleic acid is possible. The structure of cold-resistant plasticizers is generally a linear structure, so oleic acid is an ideal raw material for preparing cold-resistant plasticizers.

Disclosure of Invention

The invention aims to overcome the defects, provides a preparation method and application of the plant oil-based cold-resistant plasticizer, develops the cold-resistant plasticizer with excellent performance, and is suitable for industrial production.

The technical scheme of the invention is that oleic acid, 1, 4-cyclohexanedimethanol and hydrogen peroxide are used as main raw materials, and the epoxy 1, 4-cyclohexanedimethanol dioleate plasticizer is obtained through two steps of reactions of esterification and epoxidation, and the preparation method of the vegetable oil-based cold-resistant plasticizer comprises the following specific steps:

(1) esterification reaction: adding oleic acid and 1, 4-cyclohexanedimethanol into a reactor, introducing nitrogen, and heating for reaction; adding the catalyst 1 when the temperature rises to a certain temperature, and then raising the temperature to continue the reaction; adding sodium hydroxide solution after the catalytic reaction is finished, and heating for reaction; centrifuging after the reaction is finished, taking supernate, washing the supernate to be neutral by using deionized water, and then removing residual water by vacuum distillation to obtain a product 1, 4-cyclohexanedimethanol dioleate;

(2) epoxidation reaction: adding the 1, 4-cyclohexanedimethanol dioleate prepared in the step (1) and a catalyst 2 into a reactor, gradually dropwise adding a mixture of formic acid and hydrogen peroxide, and heating for reaction; and (3) after the reaction is finished, washing the mixture to be neutral by using deionized water, and then removing residual water by vacuum distillation to obtain the final product, namely the plant oil-based cold-resistant plasticizer: epoxy 1, 4-cyclohexanedimethanol dioleate.

Further, the catalyst 1 in the esterification reaction in the step (1) is tetrabutyl titanate.

Further, in the esterification reaction in the step (1), the raw material 1, 4-cyclohexanedimethanol: the mol ratio of the oleic acid is 1: 1-3; introducing nitrogen for 5-30 min before heating, wherein the mass of the catalyst 1 is 0.1-0.5% of the total mass of the raw materials, heating to 120-150 ℃, adding the catalyst 1, heating to 130-180 ℃, and continuing to react for 2-9 h; and after the catalytic reaction is finished, 15 to 25 mass percent of sodium hydroxide solution is added, the mixture is heated to 30 to 70 ℃, and the reaction is carried out for 0.1 to 3 hours.

Further, the mass of sodium hydroxide in the step (1) is calculated according to the acid value of the solution after the reaction is finished according to the following formula, wherein m = 7.13 × 10^-4× AV × Q + Q × 25%, wherein m is the mass of NaOH, AV is the acid value of the solution at the end of the catalytic reaction, and Q is the addition amount of oleic acid.

Further, in the step (1), the vacuum degree of vacuum distillation is-0.1 MPa, and distillation is carried out for 0.5-2 h at the temperature of 60-80 ℃.

Further, in the epoxidation reaction in the step (2), the catalyst 2 is a strong acid type cation exchange resin.

Further, in the epoxidation reaction in the step (2), the mass fraction of the hydrogen peroxide solution is 30-50%, and the molar ratio of the 1, 4-cyclohexanedimethanol dioleate to the formic acid to the hydrogen peroxide is 1: 1-3: 8-15, wherein the mass of the catalyst 2 is 3-10% of the total mass; and during heating reaction, the temperature is 40-80 ℃, and the reaction time is 4-8 h.

Further, in the step (2), the vacuum degree in the vacuum distillation is-0.1 MPa, and the distillation is carried out for 0.5-2 h at the temperature of 60-80 ℃.

The application of the vegetable oil-based cold-resistant plasticizer prepared by the method is to apply the prepared epoxy 1, 4-cyclohexanedimethanol dioleate as a main plasticizer or an auxiliary plasticizer to the preparation of PVC resin.

The invention has the beneficial effects that: the epoxy 1, 4-cyclohexanedimethanol dioleate plasticizer prepared by the method is colorless and transparent in color, low in viscosity and good in compatibility with PVC, has excellent tensile property, solvent resistance, thermal stability and cold resistance compared with DOTP and DOA applied to PVC, and is suitable for industrial production. The novel environment-friendly cold-resistant plasticizer prepared by the invention is expected to replace the traditional phthalate plasticizer.

Drawings

FIG. 1 infra-red spectra of the starting materials and products of example 3; 1. oleic acid; 2. 1, 4-cyclohexanedimethanol dioleate; 3. epoxy 1, 4-cyclohexanedimethanol dioleate.

FIG. 2 graph of the thermogravimetry of three samples of application example 1; 1. plasticizing by DOA; 2. plasticizing by DOTP; 3. epoxy 1, 4-cyclohexanedimethanol dioleate.

FIG. 3 graph of migration behavior of three samples in different solvents using example 1; 1. plasticizing by DOTP; 2. plasticizing by DOA; 3. epoxy 1, 4-cyclohexanedimethanol dioleate.

FIG. 4 DMA plots of three samples using example 1; 1. plasticizing by DOTP; 2. plasticizing by DOA; 3. epoxy 1, 4-cyclohexanedimethanol dioleate.

Detailed Description