阅读说明：本技术 一种新型聚氨酯包装材料薄膜及其制备 (Novel polyurethane packaging material film and preparation thereof ) 是由 江贵长 纵宇浩 王旭辉 于 2020-12-23 设计创作，主要内容包括：本发明公开了一种新型聚氨酯包装材料薄膜及其制备,所述聚氨酯包装材料的合成使用以下原料：六亚甲基二异氰酸酯、聚碳酸酯二元醇、二甘醇和二月桂酸二丁基锡；其制备方法为使用油浴加热,在氮气保护氛围下,六亚甲基二异氰酸酯与聚碳酸酯二元醇反应生成预聚体,然后加入扩链剂二甘醇进行扩链反应,在催化剂二月桂酸二丁基锡的作用下最终合成聚氨酯材料,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材料,配方合理,且制备得聚氨酯材料成本较低,其延展性良好,且力学性能及表面疏水性能优良。(The invention discloses a novel polyurethane packaging material film and a preparation method thereof, wherein the polyurethane packaging material is synthesized by using the following raw materials: hexamethylene diisocyanate, polycarbonate diol, diethylene glycol and dibutyltin dilaurate; the preparation method comprises the steps of heating by using an oil bath, reacting hexamethylene diisocyanate with polycarbonate diol to generate a prepolymer under the protection of nitrogen, adding a chain extender diethylene glycol to perform a chain extension reaction, finally synthesizing a polyurethane material under the action of a catalyst dibutyltin dilaurate, and performing tape casting to form a film by using a polytetrafluoroethylene plate. The polyurethane film material disclosed by the invention is reasonable in formula, and the prepared polyurethane material is low in cost, good in ductility, excellent in mechanical property and surface hydrophobic property.)

1. A novel polyurethane packaging material film comprises the following components in percentage by mass:

diisocyanate: 20.4 to 28.7 percent of the total weight of the mixture,

polyester polyol: 75.6 to 67.4 percent of the total weight of the mixture,

chain extender: 4 to 3.9 percent of the total weight of the mixture,

catalyst: 0.05 percent to 0.1 percent,

film-forming solution: 90.2 to 94.4 percent.

2. A novel polyurethane packaging material film according to claim 1, characterized in that: the diisocyanate selected is hexamethylene diisocyanate.

3. A novel polyurethane packaging material film according to claim 1, characterized in that: the polyester polyol selected was a polycarbonate diol having a molecular weight of 2000.

4. A novel polyurethane packaging material film according to claim 1, characterized in that: the small molecule chain extender selected is diethylene glycol.

5. A novel polyurethane packaging material film according to claim 1, characterized in that: the catalyst chosen was dibutyltin dilaurate.

6. A novel polyurethane packaging material film according to claim 1, characterized in that: the film forming solvent selected was N, N-dimethylformamide.

7. A novel polyurethane packaging material film according to claim 1, characterized in that: the reaction process must be carried out under a nitrogen atmosphere.

8. A preparation method of a novel polyurethane packaging material film is characterized by comprising the following steps:

(1) pretreatment of raw materials

Placing polyester polyol and a chain extender in a vacuum drying oven to be dried for 24 hours at the temperature of 80 ℃, and placing diisocyanate in a refrigerator at the temperature of-3-0 ℃ for low-temperature sealed storage;

(2) prepolymerization stage

Heating an oil bath kettle to about 60 ℃, adding polyester polyol with water removed in advance into a three-neck flask filled with nitrogen, a condenser pipe and a mechanical stirring paddle, adding diisocyanate stored at a low temperature when the temperature rises to about 90 ℃, reacting for 2 hours at the temperature, and adding a catalyst when the reaction is carried out for 1.5 hours;

(3) chain extension stage

After the reaction is carried out for 2 hours, adding a chain extender at the temperature, continuing the chain extension reaction, and if the viscosity in the reaction process is higher, adding a small amount of solvent to reduce the viscosity, and carrying out the reaction for about 8 hours to obtain the novel polyurethane;

(4) stage of film formation

The polyurethane product was dissolved in a solvent, poured onto a tetrafluoroethylene plate, the solvent was volatilized at 60 ℃, and dried in a vacuum oven to a constant weight, thereby obtaining a polyurethane film.

Technical Field

The invention relates to a novel polyurethane packaging material film and a preparation method thereof, in particular to a novel polyurethane packaging material film with excellent water resistance and mechanical properties and a preparation method thereof.

Background

Polyurethane is a general name for high molecular polymers containing an imido group (-NH-CO-O) in the molecular chain, and is abbreviated as PU (polyurethane). Usually prepared by reacting a polyisocyanate with a polyol-containing compound or polymer. The polyurethane film used as a packaging material is a thermoplastic polyurethane elastomer (abbreviated as TPU). The polyurethane elastomer is a high molecular synthetic material between rubber and plastic, and the main molecular chain is formed by inlaying and combining a flexible chain segment and a rigid chain segment. The structure of the polyurethane elastomer contains a large number of polar groups such as carbamate groups, ester urea groups and the like, the existence of the polar groups and the mutual action of the polar groups endow the polyurethane elastomer with a series of excellent performances, and the polyurethane film is rapidly developed due to the reasons of easy use, diversified functions and the like of film products and has wide and unique application in a plurality of fields.

Disclosure of Invention

The invention aims to solve the defects in the prior art, prepare a polyurethane film with good mechanical property and excellent hydrophobicity, and also provide a method for preparing the film.

The technical scheme adopted by the invention for solving the technical problem is as follows:

a novel polyurethane packaging material film comprises the following components in percentage by mass:

diisocyanate: 20.4 to 28.7 percent of the total weight of the mixture,

polyester polyol: 75.6 to 67.4 percent of the total weight of the mixture,

chain extender: 4 to 3.9 percent of the total weight of the mixture,

catalyst: 0.05 percent to 0.1 percent,

film-forming solution: 90.2 to 94.4 percent.

The preparation method of the novel polyurethane packaging material film comprises the following steps:

(1) pretreatment of raw materials

Placing polyester polyol and a chain extender in a vacuum drying oven to be dried for 24 hours at the temperature of 80 ℃, and placing diisocyanate in a refrigerator at the temperature of-3-0 ℃ for low-temperature sealed storage;

(2) prepolymerization stage

Heating an oil bath kettle to about 60 ℃, adding polyester polyol with water removed in advance into a three-neck flask filled with nitrogen, a condenser pipe and a mechanical stirring paddle, adding diisocyanate stored at a low temperature when the temperature rises to about 90 ℃, reacting for 2 hours at the temperature, and adding a catalyst when the reaction is carried out for 1.5 hours;

(3) chain extension stage

After the reaction is carried out for 2 hours, adding a chain extender at the temperature, continuing the chain extension reaction, and if the viscosity in the reaction process is higher, adding a small amount of solvent to reduce the viscosity, and carrying out the reaction for about 8 hours to obtain the novel polyurethane;

(4) stage of film formation

The polyurethane product was dissolved in a solvent, poured onto a tetrafluoroethylene plate, the solvent was volatilized at 60 ℃, and dried in a vacuum oven to a constant weight, thereby obtaining a polyurethane film.

Moreover, the polyester polyol is polycarbonate diol.

Further, the diisocyanate is hexamethylene diisocyanate.

And, the chain extender is diethylene glycol.

Further, the catalyst is dilaurate dibutyl butene.

Furthermore, the organic solvent is N, N-dimethylformamide.

The invention has the advantages and positive effects that:

(1) the polyurethane film prepared by the invention has good ductility and mechanical properties.

(2) The polyurethane film prepared by the invention has good hydrophobicity and attractive appearance.

(3) The polyurethane prepared by the invention does not contain aromatic isocyanate and has the characteristics of environmental protection and no harm.

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 polyurethane film formulations

(1) Pretreatment of raw materials

Placing polycarbonate dihydric alcohol and diethylene glycol in a vacuum drying oven to be dried for 24 hours at 80 ℃, and storing hexamethylene diisocyanate in a refrigerator at the temperature of-3-0 ℃ in a sealed manner at low temperature;

(2) prepolymerization stage

Heating an oil bath kettle to about 60 ℃, adding polycarbonate diol from which water is removed in advance into a three-neck flask filled with nitrogen, a condenser pipe and a mechanical stirring paddle, adding hexamethylene diisocyanate stored at a low temperature when the temperature of the polycarbonate diol rises to about 90 ℃, reacting for 2 hours at the temperature, and adding a catalyst when the reaction is carried out for 1.5 hours;

(3) chain extension stage

After the reaction is carried out for 2 hours, adding diglycol at the temperature, continuing the chain extension reaction, and if the viscosity in the reaction process is higher, adding a small amount of N, N-dimethylformamide to reduce the viscosity, and carrying out the reaction for about 8 hours to obtain the novel polyurethane;

(4) stage of film formation

The polyurethane product was dissolved in a solvent, poured onto a tetrafluoroethylene plate, the solvent was volatilized at 60 ℃, and dried in a vacuum oven to a constant weight, thereby obtaining a polyurethane film.

(5) 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 polyurethane film formulations

Other steps are the same as in the first embodiment.

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 polyurethane film formulations

Other steps are the same as in the first embodiment.

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 polyurethane film formulations

Other steps are the same as in the first embodiment.

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 polyurethane film formulations

Other steps are the same as in the first embodiment.

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.