CN116023622A - Thermoplastic polyurethane board and preparation method thereof - Google Patents

Abstract

The application relates to a thermoplastic polyurethane board and a preparation method thereof. The thermoplastic polyurethane board comprises the following raw materials in percentage by mass: 60-65% of isocyanate; 10-15% polytetrahydrofuran ether glycol; 20-25% of small molecule diol; 1% of ultraviolet absorber. The preparation method comprises the following steps: weighing raw materials; heating polytetrahydrofuran ether glycol in vacuum; mixing part of micromolecular diol, an ultraviolet absorbent and dehydrated polytetrahydrofuran ether glycol, heating and stirring to obtain a reactant; adding isocyanate into the reactant, heating and stirring to obtain a first material; heating the other part of small molecular diol to obtain a second material; mixing the first material and the second material under vacuum condition, and stirring to obtain a casting material; pouring the pouring material into a mould, and curing at a high temperature in stages to obtain the thermoplastic polyurethane board. The thermoplastic polyurethane board prepared by the method has excellent ageing resistance.

Description

Thermoplastic polyurethane board and preparation method thereof

Technical Field

The application relates to a PC board, in particular to a thermoplastic polyurethane board and a preparation method thereof.

Background

PC board is also called acid ester board, weak acid resistant is prepared by using polycarbonate as main component and adopting coextrusion technology, but the existing PC board has poor ageing resistance, and in order to prolong the service life, an extra ultraviolet-resistant coating is required. Therefore, it is urgently required to design a PC board with good ageing resistance.

Disclosure of Invention

In order to solve the problems in the prior art, embodiments of the present application provide a thermoplastic polyurethane board and a preparation method thereof. The specific technical scheme is as follows:

in a first aspect, a thermoplastic polyurethane board is provided, and the preparation raw materials of the thermoplastic polyurethane board comprise the following components in percentage by mass: 60-65% of isocyanate; 10-15% polytetrahydrofuran ether glycol; 20-25% of small molecule diol; 1% of ultraviolet absorber.

In a first possible implementation of the first aspect, the isocyanate includes at least one of isocyanate, p-phenylene diisocyanate, isophorone diisocyanate, and 1, 5-naphthalene diisocyanate.

In a second possible implementation of the first aspect, the polytetrahydrofuran ether glycol has a molecular weight of 250-3000.

In a third possible implementation manner of the first aspect, the small molecule diol includes at least one of ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 3-butanediol, and 1, 5-pentanediol.

In a fourth possible implementation of the first aspect, the ultraviolet absorber comprises at least one of UV-329, UV-328 and UV-1130.

In a second aspect, a method for preparing a thermoplastic polyurethane board is provided, comprising the steps of:

(a) Weighing the raw material of the thermoplastic polyurethane board according to any one of the first aspects;

(b) Heating polytetrahydrofuran ether glycol in vacuum to make the mass fraction of water in polytetrahydrofuran ether glycol be less than or equal to 0.05%;

(c) Mixing part of micromolecular diol, an ultraviolet absorbent and dehydrated polytetrahydrofuran ether glycol, heating and stirring to obtain a reactant;

(d) Adding isocyanate into the reactant, heating and stirring to obtain a first material;

(e) Heating the other part of small molecular diol to obtain a second material;

(f) Mixing the first material and the second material under vacuum condition, and stirring to obtain a casting material;

(g) Pouring the pouring material into a mould, and curing at a high temperature in stages to obtain the thermoplastic polyurethane board.

In a first possible implementation of the second aspect, in step (b), polytetrahydrofuran ether glycol is added to a three-neck flask equipped with a stirrer, thermometer, heated to 100-110 ℃, and dehydrated under vacuum for 2-3h.

In a second possible implementation manner of the second aspect, in the step (c), a part of the small molecule diol, the ultraviolet absorber and the dehydrated polytetrahydrofuran ether diol are added into a wide-neck flask, and stirred using an emulsifying and dispersing machine, and the oil bath is heated to 110 ℃.

In a third possible implementation manner of the second aspect, in the step (d) and the step (e), the heating and stirring temperature is 110 ℃, and the stirring time is 2-3h.

In a fourth possible implementation manner of the second aspect, in the step (g), at the time of the stage high temperature curing, the stage curing is performed in such a manner that the heating is performed at 115 ℃, the heat is kept for 2 hours, the heating is performed at 145 ℃, the heat is kept for 2 hours, and the heating is performed at 160 ℃ and the heat is kept for 26 hours.

Compared with the prior art, the application has the advantages that:

according to the thermoplastic polyurethane board and the preparation method thereof, the prepared thermoplastic polyurethane board has excellent ageing resistance under the condition of having the performance of the existing polyurethane board, so that an extra ultraviolet-proof coating is not required, and the production cost and the working procedures are reduced.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute an undue limitation to the application. In the drawings:

FIG. 1 is a flow chart of the steps of a method of preparing a thermoplastic polyurethane board in accordance with one embodiment of the present application.

Detailed Description

The acid ester plate is prepared by adopting a coextrusion technology by taking polycarbonate as a main component, but has poor ageing resistance, and an additional ultraviolet-resistant coating is usually required.

The thermoplastic polyurethane board prepared by the method has excellent ageing resistance under the condition of having the performance of the existing polyurethane board, so that an extra ultraviolet-proof coating is not required, and the production cost and the working procedures are reduced.

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

Examples

Weighing the following preparation raw materials of the thermoplastic polyurethane board: 62% by mass of isocyanate (HMDI), 15% by mass of polytetrahydrofuran ether glycol, 22% by mass of small molecule glycol and 1% by mass of UV-328.

Referring to fig. 1, a flowchart of steps of a method for preparing a thermoplastic polyurethane board according to an embodiment of the present application is shown. The thermoplastic polyurethane board is prepared according to the above-mentioned weighed raw materials, and the preparation method S of the thermoplastic polyurethane board comprises the following steps S1 to S6. Wherein:

in step S1, the polytetrahydrofuran ether glycol is heated in vacuum so that the mass fraction of water in the polytetrahydrofuran ether glycol is less than or equal to 0.05 percent. Specifically, polytetrahydrofuran ether glycol is added into a three-neck flask with a stirrer and a thermometer, heated to 100-110 ℃, and dehydrated for 2-3 hours under vacuum, so that the mass fraction of water in the material is not higher than 0.05%.

In the step S2, part of micromolecular diol, an ultraviolet absorbent and dehydrated polytetrahydrofuran ether glycol are mixed, heated and stirred to obtain a reactant. Specifically, a part of the small molecular diol, the ultraviolet absorber UV-328 and the dehydrated polytetrahydrofuran ether glycol are added into a wide-mouth flask, and stirred by using an emulsifying and dispersing machine, and heated to 110 ℃ by an oil bath.

In step S3, isocyanate is added to the reactant, heated and stirred to obtain a first material. Specifically, the metered isocyanate is slowly added into the wide-mouth flask (reactant), and the mixture is heated and stirred at 110 ℃ for 2-3 hours to react, so that the preparation of the first material is completed after the theoretical NCO content is reached.

In step S4, another part of the small molecular diol is heated to obtain a second material. Specifically, the remaining small molecular diol was heated and stirred at 110 ℃ to obtain a second material.

In step S5, the first material and the second material are mixed under vacuum, and stirred, to obtain a casting material. Specifically, the first material and the second material are respectively placed in a vacuum container, the vacuum container is vacuumized, then the first material and the second material are mixed, and the casting material is obtained after the mixture is stirred until the mixture is clarified.

In the step S6, pouring the pouring material into a mould, and curing at a high temperature in stages to obtain the thermoplastic polyurethane board. Specifically, the prepared castable is poured into a flat plate-shaped mold, and is subjected to stage solidification according to the mode of heating 115 ℃, preserving heat for 2 hours, heating 145 ℃, preserving heat for 2 hours, heating 160 ℃ and preserving heat for 26 hours, and then cooling and demolding to obtain the thermoplastic polyurethane plate.

The properties of the thermoplastic polyurethane sheet prepared above were tested and the test data were as follows:

1. tensile strength: 76.27MPa;

2. elongation at break: 209.21%;

3. and (3) radiation resistance test: haze <1% after 4 weeks.

From the above test, the thermoplastic polyurethane board prepared in this embodiment not only has better tensile strength and elongation at break, but also has excellent aging resistance.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The embodiments of the present application have been described above with reference to the accompanying drawings, but the present application is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many forms may be made by those of ordinary skill in the art without departing from the spirit of the present application and the scope of the claims, which are also within the protection of the present application.

Claims (10)

1. The thermoplastic polyurethane board is characterized by comprising the following raw materials in percentage by mass:

60-65% of isocyanate;

10-15% polytetrahydrofuran ether glycol;

20-25% of small molecule diol;

1% of ultraviolet absorber.

2. The thermoplastic polyurethane board of claim 1, wherein the isocyanate comprises at least one of isocyanate, terephthal-diisocyanate, isophorone diisocyanate, and 1, 5-naphthalene diisocyanate.

3. The thermoplastic polyurethane slab of claim 1, wherein the polytetrahydrofuran ether glycol has a molecular weight of 250 to 3000.

4. The thermoplastic polyurethane board of claim 1, wherein the small molecule diol comprises at least one of ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 3-butanediol, and 1, 5-pentanediol.

5. The thermoplastic polyurethane board of claim 1, wherein the ultraviolet absorber comprises at least one of UV-329, UV-328 and UV-1130.

6. The preparation method of the thermoplastic polyurethane board is characterized by comprising the following steps of:

(a) Weighing raw materials according to any one of the above claims 1 to 5;

(b) Heating the polytetrahydrofuran ether glycol in vacuum to ensure that the mass fraction of water in the polytetrahydrofuran ether glycol is less than or equal to 0.05%;

(c) Mixing part of the micromolecular diol, the ultraviolet absorbent and the dehydrated polytetrahydrofuran ether glycol, heating and stirring to obtain a reactant;

(d) Adding the isocyanate into a reactant, heating and stirring to obtain a first material;

(e) Heating another part of the small molecular diol to obtain a second material;

(f) Mixing the first material and the second material under vacuum, and stirring to obtain a casting material;

(g) And pouring the pouring material into a mould, and curing at a stage of high temperature to obtain the thermoplastic polyurethane board.

7. The method for producing a thermoplastic polyurethane slab according to claim 6, wherein in the step (b), the polytetrahydrofuran ether glycol is added to a three-necked flask equipped with a stirrer and a thermometer, heated to 100 to 110℃and dehydrated under vacuum for 2 to 3 hours.

8. The method for producing a thermoplastic polyurethane slab according to claim 6, wherein in the step (c), a part of the small molecular diol, the ultraviolet absorber and the dehydrated polytetrahydrofuran ether glycol are added to a wide-neck flask, and stirred by using an emulsifying and dispersing machine, and heated in an oil bath at 110 ℃.

9. The method of producing a thermoplastic polyurethane slab according to claim 6, wherein in said step (d) and said step (e), the heating and stirring temperature is 110℃and the stirring time is 2 to 3 hours.

10. The method for producing a thermoplastic polyurethane slab according to claim 6, wherein in the step (g), the step (c) is performed by heating at 115℃for 2 hours, heating at 145℃for 2 hours, and heating at 160℃for 26 hours.

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