阅读说明：本技术 一种植物油基聚氨酯薄膜及其制备 (Vegetable oil-based polyurethane film and preparation thereof ) 是由 江贵长 林健伟 王旭辉 于 2020-11-25 设计创作，主要内容包括：一种植物油基聚氨酯薄膜及其制备。所述制备方法包括以下步骤：以环氧大豆油、聚乙二醇、浓硫酸制备羟基化环氧大豆油；按照一定的比例,将二异氰酸酯和羟基化环氧大豆油,并添加催化剂,使用油浴加热,在氮气保护氛围下,制备植物油基聚氨酯,并使用聚四氟乙烯板进行流延成膜。本发明中的聚氨酯薄膜具有良好的疏水性、韧性和延展性,同时使用植物油基原料克服了材料难以降解等困难。(A vegetable oil-based polyurethane film and its preparation are provided. The preparation method comprises the following steps: preparing hydroxylated epoxidized soybean oil from epoxidized soybean oil, polyethylene glycol and concentrated sulfuric acid; according to a certain proportion, diisocyanate and hydroxylated epoxidized soybean oil are added with a catalyst, heated by an oil bath, under the protection of nitrogen, vegetable oil-based polyurethane is prepared, and a polytetrafluoroethylene plate is used for tape casting to form a film. The polyurethane film has good hydrophobicity, toughness and ductility, and simultaneously, the difficulties that the material is difficult to degrade and the like are overcome by using the vegetable oil-based raw material.)

1. A vegetable oil-based polyurethane film, comprising the steps of:

(1) preparation of hydroxylated epoxy vegetable oil: adopting a 250ml round bottom three-neck flask which is respectively connected with a mechanical stirrer, a condenser and a nitrogen inlet and outlet as a hydroxylation reaction container, adding polyethylene glycol, epoxy vegetable oil and a catalyst according to a certain proportion for reaction, and heating in an oil bath in the whole reaction process;

(2) preparation of vegetable oil-based polyurethane film: adding hydroxylated epoxy vegetable oil, diisocyanate and a catalyst into a reactor according to a certain proportion, reacting in an oil bath at 70-90 ℃ for 15-30min, pouring into a beaker, adding an organic solvent for dissolving, pouring the dissolved solution onto a tetrafluoroethylene plate, and putting into a 30-70 ℃ oven to dry the solvent, thus obtaining the vegetable oil-based polyurethane film.

2. The vegetable oil-based polyurethane film according to claim 1, wherein the reaction is terminated by adding a proper amount of sodium carbonate solution after heating in step (1), and further comprising a separation and purification step.

3. The vegetable oil-based polyurethane film according to claim 1, wherein in the step (1), the film is heated to 100-120 ℃ and the reaction time is 2-3 h.

4. The vegetable oil-based polyurethane film according to claim 1, wherein the epoxidized vegetable oil of step (1) is epoxidized soybean oil.

5. The vegetable oil-based polyurethane film as claimed in claim 1, wherein the polyethylene glycol of step (1) is one of polyethylene glycol 200, polyethylene glycol 400 and polyethylene glycol 600.

6. The vegetable oil-based polyurethane film as claimed in claim 1, wherein the molar ratio of the polyethylene glycol to the epoxidized vegetable oil in the step (1) is 1.6: 1 to 3: 1.

7. The vegetable oil-based polyurethane film as claimed in claim 1, wherein the catalyst in step (1) is concentrated sulfuric acid, and the amount of the concentrated sulfuric acid is 0.3-0.5% of the total weight of the hydroxylated epoxy vegetable oil.

8. The vegetable oil-based polyurethane film according to claim 1, wherein the diisocyanate in step (2) is isophorone diisocyanate and the amount of the isophorone diisocyanate is 30-39.15% of the total mass of the film-forming material.

9. The vegetable oil-based polyurethane film as claimed in claim 1, wherein the amount of the hydroxylated epoxy vegetable oil used in the step (2) is 60.68-69.83% of the total mass of the film-forming material.

10. The vegetable oil-based polyurethane film as claimed in claim 1, wherein the catalyst in step (2) is dibutyltin dilaurate in an amount of 0.13-0.17% by mass of the total mass of the film forming material; the organic solvent in the step (2) is N, N-dimethylformamide, and a proper amount of organic solvent can be added when the viscosity is too high in the reaction process; the reaction process of the step (1) and the step (2) must be carried out in a nitrogen environment.

Technical Field

The invention relates to the field of high polymer materials, in particular to a vegetable oil-based polyurethane film and a preparation method thereof.

Background

With the increasingly wide application of polymer films in the field of packaging, the requirements on the film performance are more strict, and compared with the single performance of other films, the polyurethane has good comprehensive performance. Polyurethane is a new organic polymer material, and polyurethane is called as 'fifth plastic' in the field of polymer materials, and is widely applied to various fields of national economy due to excellent performance. The application field of the product relates to light industry, chemical industry, electronics, textile, medical treatment, building materials, automobiles, national defense, aerospace, aviation and the like. Polyurethane products are also growing in china. Compared with other polymer films, the polyurethane film has excellent tension, toughness, ageing resistance, wear resistance, impact resistance and the like. The processing technology is simple, and the cost can be reduced. Polyurethanes are generally synthesized by polyaddition polymerization of polyols and diisocyanates. Hydroxyl-terminated polyester and hydroxyl-terminated polyether for synthesizing polyurethane in the prior art are mainly from petrochemical resource routes, and petrochemical resources are easy to be in short supply, so that the adoption of bio-based polyol to replace polyester and polyether polyol is a hot point of research.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a novel polyurethane film with high performance and exquisite appearance. Through comparative research on the existing polyurethane synthetic materials, the vegetable oil-based polyurethane film with good mechanical property, exquisite appearance and good hydrophobicity is prepared, and meanwhile, the method for preparing the film is provided.

The purpose of the invention is realized by the following scheme:

a vegetable oil-based polyurethane film comprising the steps of:

(1) preparation of hydroxylated epoxy vegetable oil: adopting a 250ml round bottom three-neck flask which is respectively connected with a mechanical stirrer, a condenser and a nitrogen inlet and outlet as a hydroxylation reaction container, adding polyethylene glycol, epoxy vegetable oil and a catalyst according to a certain proportion for reaction, and heating in an oil bath in the whole reaction process;

(2) preparation of vegetable oil-based polyurethane film: adding hydroxylated epoxy vegetable oil, diisocyanate and a catalyst into a reactor according to a certain proportion, reacting in an oil bath at 70-90 ℃ for 15-30min, pouring into a beaker, adding an organic solvent for dissolving, pouring the dissolved solution onto a tetrafluoroethylene plate, putting the tetrafluoroethylene plate into a 30-70 ℃ oven, and drying the solvent to obtain the vegetable oil-based polyurethane film.

Heating the mixture in the step (1), adding a proper amount of sodium carbonate solution to terminate the reaction, and further comprising a separation and purification step, wherein the separation and purification step comprises the following steps: and cooling the mixture to room temperature, extracting unreacted polyethylene glycol with deionized water, separating the solution, drying the organic layer to remove water, and performing rotary evaporation to obtain the yellowish viscous liquid hydroxylated epoxy vegetable oil.

In the step (1), the temperature is heated to 100-120 ℃, and the reaction time is 2-3 h.

The epoxidized vegetable oil in the step (1) is epoxidized soybean oil.

The polyethylene glycol in the step (1) is one of polyethylene glycol 200, polyethylene glycol 400 and polyethylene glycol 600.

The molar ratio of the polyethylene glycol to the epoxy vegetable oil in the step (1) is 1.6: 1-3: 1.

The catalyst in the step (1) is concentrated sulfuric acid, and the dosage of the concentrated sulfuric acid is 0.3-0.5% of the total weight of the hydroxylated epoxy vegetable oil in the reaction.

The diisocyanate in the step (2) is isophorone diisocyanate, and the usage amount of the diisocyanate is 30-39.16% of the total mass of the film forming material.

The dosage of the hydroxylated epoxy vegetable oil in the step (2) is 60.68-69.83% of the total mass of the film-forming material.

In the step (2), the catalyst is dibutyltin dilaurate, and the dosage of the catalyst is 0.13-0.17% of the total mass of the film forming substance.

The organic solvent in the step (2) is N, N-dimethylformamide, and a proper amount of organic solvent can be added when the viscosity is too high in the reaction process.

The reaction process of the step (1) and the step (2) must be carried out in a nitrogen environment.

The invention has the advantages and positive effects that:

(1) opens up a new application field for natural materials, improves the use value of the natural materials, and greatly relieves the pressure of petrochemical industry.

(2) The polyurethane film prepared by the invention has good aesthetic property.

(3) The polyurethane film prepared by the invention has good hydrophobicity.

(4) The polyurethane film prepared by the invention has good toughness and ductility.

Drawings

FIG. 1 is a flow chart of the method of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments, which are illustrative only and not limiting, and the scope of the present invention is not limited thereby.

Example 1

In this example, we performed experimental studies using the formulations in table 1:

TABLE 1 vegetable oil based polyurethane film formulations

(1) Preparation of hydroxylated epoxy vegetable oil: the method comprises the steps of adopting a 250ml round bottom three-necked flask which is respectively connected with a mechanical stirrer, a condenser and a nitrogen inlet and outlet as a hydroxylation reaction container, adding concentrated sulfuric acid which accounts for 0.5% of the total weight of the hydroxylation epoxy vegetable oil reaction according to the molar ratio of polyethylene glycol 600 to epoxy soybean oil of 1.66: 1, heating the mixture in 100 ℃ oil bath for 3 hours in the nitrogen environment in the whole reaction process, adding 10ml of 0.1mol/l sodium carbonate solution to terminate the reaction, cooling the mixture to room temperature, extracting unreacted polyethylene glycol with deionized water, separating the liquid, drying the organic layer to remove water, and performing rotary evaporation to obtain the light yellow viscous liquid hydroxylation epoxy vegetable oil.

(2) Preparation of vegetable oil-based polyurethane film: hydroxylated epoxy vegetable oil, isophorone diisocyanate, dibutyltin dilaurate were added to the reactor according to the formulation in Table 1, reacted in an oil bath at 80 ℃ and 5ml of N, N-dimethylformamide was added when a large amount of bubbles appeared.

(3) Film formation

Pouring the polyurethane prepolymer into a beaker, pouring N, N-dimethylformamide, dissolving the prepolymer by a solvent at 40 ℃ under magnetic stirring, pouring the dissolved product onto a polytetrafluoroethylene plate, and drying in a 50 ℃ oven to form a film.

(4) Performance testing

Mechanical properties

Test specimens were prepared according to ASTM D-882 test standards and the films were tested for tensile strength and elongation at break. The test results are shown in Table 6.

② water contact angle

Test bars were prepared according to GB/T30693-2014 test standards and the films were tested for water contact angle. The test results are shown in Table 6.

Example 2

In this example, we performed experimental studies using the formulations in table 2:

TABLE 2 vegetable oil based polyurethane film formulations

The other steps are the same as those in embodiment 1.

Performance testing

Mechanical properties

Test specimens were prepared according to ASTM D-882 test standards and the films were tested for tensile strength and elongation at break. The test results are shown in Table 6.

② water contact angle

Test bars were prepared according to GB/T30693-2014 test standards and the films were tested for water contact angle. The test results are shown in Table 6.

Example 3

In this example, we performed experimental studies using the formulations in table 3:

TABLE 3 vegetable oil based polyurethane film formulations

The other steps were the same as in examples 1 to 2.

Performance testing

Mechanical properties

Test specimens were prepared according to ASTM D-882 test standards and the films were tested for tensile strength and elongation at break. The test results are shown in Table 6.

② water contact angle

Test bars were prepared according to GB/T30693-2014 test standards and the films were tested for water contact angle. The test results are shown in Table 6.

Example 4

In this example, we performed experimental studies using the formulation in table 4:

TABLE 4 vegetable oil based polyurethane film formulations

The other steps are the same as in embodiments 1 to 3.

Performance testing

Mechanical properties

Test specimens were prepared according to ASTM D-882 test standards and the films were tested for tensile strength and elongation at break. The test results are shown in Table 6.

② water contact angle

Test bars were prepared according to GB/T30693-2014 test standards and the films were tested for water contact angle. The test results are shown in Table 6.

Example 5

In this example, we performed experimental studies using the formulation in table 5:

TABLE 5 vegetable oil based polyurethane film formulations

The other steps are the same as in embodiments 1 to 4.

Performance testing

Mechanical properties

Test specimens were prepared according to ASTM D-882 test standards and the films were tested for tensile strength and elongation at break. The test results are shown in Table 6.

② water contact angle

Test bars were prepared according to GB/T30693-2014 test standards and the films were tested for water contact angle. The test results are shown in Table 6.

TABLE 6 test results for finished products obtained in examples one to five

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the inventive concept, and these changes and modifications are all within the scope of the present invention.