High-temperature-resistant film and preparation method thereof

Abstract

The invention is applicable to the field of high-temperature-resistant materials, and discloses a high-temperature-resistant film and a preparation method thereof.The high-temperature-resistant film comprises trihydroxy polyoxypropylene ether, polytetramethyl ether glycol, polypropylene carbonate glycol, polyisocyanate and a chain extender; the high-temperature-resistant film and the preparation method thereof disclosed by the invention show remarkable advantages in the aspects of mechanical properties, heat resistance, aging resistance, light transmission and the like. According to the preparation method, the three polyols are subjected to mutual synergistic reaction to form an interpenetrating network, the mechanical property of a finished product is enhanced, specifically, the trihydroxy polyoxypropylene ether serves as the trifunctional polyols, molecular chain segments are flexible, a large number of branched chains can be formed in a cross-linked network, and the mechanical strength and toughness of the membrane material are effectively enhanced. Meanwhile, the molecular chain of the polytetramethyl ether glycol and the side group structure of the polypropylene carbonate glycol supplement each other, and through the formation of an interpenetrating network, the impact resistance and the fatigue resistance of the film are greatly improved, so that the film has excellent performance when facing various stress challenges.

Description

Technical Field

[0001] The present application relates to the field of high temperature resistant materials, and in particular to a high temperature resistant film and a preparation method thereof. Background Art

[0002] With the continuous development of industrial technology and the increasing expansion of application fields, the importance of high temperature resistant materials in many fields has become increasingly prominent. Especially in optical instruments, protective products and special environmental applications that require high temperature resistance, the performance requirements of high temperature resistant films are more stringent. However, the high temperature resistant transparent film formulas currently widely used in the market have obvious deficiencies in many aspects. These deficiencies are mainly reflected in insufficient aging resistance, low transmittance and poor impact resistance. Specifically, many existing formulas are prone to yellowing under high temperature and long-term ultraviolet irradiation conditions, which seriously affects the appearance and service life of the product. At the same time, its transmittance and energy absorption rate are often difficult to meet the design requirements, limiting its application in high-end fields. Summary of the invention

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a high temperature resistant film, which comprises the following components calculated by weight:

[0004]

[0005] More specifically, in the above technical solution, the trihydroxy polyoxypropylene ether, polytetramethyl ether diol and polypropylene carbonate diol are a polyol mixture, and the total weight of the polyisocyanate is 50%-80% of the total weight of the other components in the high temperature resistant film.

[0006] More specifically, in the above technical solution, the polyisocyanate comprises the following components, calculated by weight: 20-30 parts of polycaprolactone and 90-110 parts of isophorone diisocyanate.

[0007] More specifically, in the above technical solution, the polyisocyanate further comprises the following components calculated by weight: 0.5-1 part of ultraviolet absorber.

[0008] More specifically, in the above technical solution, the method for preparing the polyisocyanate comprises: heating the mixture of the polycaprolactone and the ultraviolet absorber to 100-120°C, removing water in vacuo, cooling to 75-85°C, adding the isophorone diisocyanate, and reacting at a constant temperature until the hydroxyl value reaches 27-31 mgKOH / g.

[0009] More specifically, in the above technical solution, the high temperature resistant membrane further comprises the following components calculated by weight: 0.4-3 parts of catalyst.

[0010] More specifically, in the above technical solution, the high temperature resistant film further comprises the following components calculated by weight: 1-5 parts of a surfactant.

[0011] More specifically, in the above technical solution, the high temperature resistant film further comprises the following components calculated by weight: 0.1-2 parts of light stabilizer.

[0012] The present application also proposes a method for preparing a high temperature resistant film, comprising mixing the raw material components of any of the above-mentioned high temperature resistant films in proportion, coating the mixed raw materials on a substrate, and drying the substrate.

[0013] To be more specific, in the above technical solution, the stirring speed is 25-35r / min, the stirring temperature is 25-35°C; the drying temperature is: 100°C in the front section, 130°C in the middle section, and 130°C in the rear section.

[0014] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0015] 1. This application uses trihydroxy polyoxypropylene ether, polytetramethyl ether glycol and polypropylene carbonate glycol as polyol mixtures, which form a unique three-dimensional interpenetrating network structure through complex cross-linking. This structure not only enhances the overall toughness and elasticity of the membrane material, but also significantly improves the mechanical strength and impact resistance, so that the high-temperature resistant membrane can still maintain excellent mechanical performance under high temperature and complex stress environments.

[0016] 2. The reaction of polypropylene carbonate diol and isophorone diisocyanate introduces a rigid group, which effectively improves the heat resistance of the product, so that the high-temperature resistant film can still maintain stable performance under high temperature environment, thereby improving the product's yellowing resistance at high temperature.

[0017] 3. Isophorone diisocyanate (IPDI) has a unique irregular structure, which reduces light scattering and improves the light transmittance of the film. Combined with the flexibility of polycaprolactone, the high temperature resistant film prepared in this application has excellent yellowing resistance while maintaining high light transmittance, and can remain clear and transparent even under long-term light conditions. DETAILED DESCRIPTION

[0018] The following will be combined with the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0020] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the phrase "in some embodiments" appearing in different places in this specification does not necessarily refer to the same embodiment, but means "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0021] The materials and reagents in this application can be purchased from the market.

[0022] The present application provides a high temperature resistant film, which comprises the following components calculated by weight:

[0023]

[0024] Trihydroxy polyoxypropylene ether, polytetramethyl ether glycol and polypropylene carbonate glycol can work together to form an interpenetrating network after reaction, thus enhancing the mechanical properties of the finished product. During the reaction, the three polyols, trihydroxy polyoxypropylene ether, polytetramethyl ether glycol and polypropylene carbonate glycol, form a unique three-dimensional interpenetrating network structure through complex cross-linking. This structure enhances the overall toughness and elasticity of the membrane material, allowing the finished product to maintain excellent impact resistance under high temperature and complex stress environments.

[0025] The trihydroxy polyoxypropylene ether (CAS Number: 25791-96-2) is a trifunctional polyol with a molecular weight of 100-2500. It acts as a cross-linking point in the network and links the isocyanate chains while giving the finished product viscoelasticity at the use temperature. The small molecular weight enables it to form a large number of side chains in the cross-linking network, which can effectively convert mechanical energy into internal energy when the finished product is impacted.

[0026] The polytetramethyl ether glycol (CAS Number: 25190-06-1) is one or more of PTMG1000, PTMG1800 and PTMG2000 produced by Formosa Plastics Corporation. The molecular chain of polytetramethyl ether glycol is flexible and can provide good elasticity.

[0027] The polypropylene carbonate diol (CAS Number: 25511-85-7) is a difunctional polyol with a molecular weight of 1000-4000. The polypropylene carbonate diol molecular chain has multiple side groups and strong cohesion, which can improve the mechanical strength of the product. At the same time, the polypropylene carbonate diol reacts with isophorone diisocyanate to introduce a rigid group to effectively improve the heat resistance of the product, thereby improving the yellowing resistance of the finished product at high temperatures.

[0028] The chain extender is selected from one or more of 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol and triethanolamine produced by Xinjiang Meike Chemical Co., Ltd.

[0029] After the introduction of these chain extenders, the structure of the polyurethane molecular chain is further optimized, the thermal motion between chain segments is reduced, and the glass transition temperature (Tg) of the material is increased, thereby significantly enhancing the stability of the film in high temperature environments.

[0030] It is understood that in the present application, the amount of each component in the high temperature resistant film can be adjusted according to the above definition, for example:

[0031] The trihydroxy polyoxypropylene ether can be 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts or 80 parts, etc.;

[0032] The polytetramethyl ether glycol can be 5 parts, 8 parts, 12 parts, 18 parts or 23 parts, 25 parts or 29 parts, etc.;

[0033] The polypropylene carbonate diol can be 5 parts, 9 parts, 15 parts, 18 parts, 22 parts, 25 parts or 28 parts, etc.;

[0034] The polyisocyanate can be 4 parts, 5 parts, 6 parts, 7 parts or 8 parts, etc.;

[0035] The chain extender can be 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts or 9 parts, etc.

[0036] In some embodiments, the trihydroxy polyoxypropylene ether, polytetramethyl ether glycol and polypropylene carbonate glycol are a polyol mixture, and the total weight of the polyisocyanate is 50%-80% of the total weight of the other components in the high temperature resistant film.

[0037] By using trihydroxy polyoxypropylene ether, polytetramethyl ether glycol and polypropylene carbonate glycol as polyol mixtures and accurately controlling the proportion of polyisocyanate, sufficient cross-linking points can be formed to successfully prepare a high-performance high-temperature resistant film composition. While maintaining high light transmittance, the product also has excellent mechanical properties and heat and yellowing resistance, which can meet various demanding application requirements.

[0038] In some embodiments, the polyisocyanate comprises the following components, calculated by weight: 20-30 parts of polycaprolactone and 90-110 parts of isophorone diisocyanate.

[0039] Isophorone diisocyanate (IPD I) has a unique irregular structure, which makes it difficult for the polyurethane hard segment to form strong crystals, thereby reducing light scattering and improving the light transmittance of the film. At the same time, IPD I does not contain a benzene ring, which avoids the formation of a colored quinone structure due to oxidation of the benzene ring under light conditions, further ensuring the transparency stability of the film after long-term use.

[0040] Polycaprolactone (PCL), as a semi-crystalline polyester, has good flexibility and toughness. When combined with IPD I, it can effectively absorb and disperse external impact energy and enhance the impact resistance of the film.

[0041] In some embodiments, the polyisocyanate further comprises the following components, calculated by weight: 0.5-1 part of ultraviolet absorber.

[0042] Optionally, the ultraviolet absorber is one of 2,4-dihydroxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone and phenyl o-hydroxybenzoate.

[0043] The UV absorber can effectively absorb light energy in the UV band and release it by converting it into harmless heat energy or longer wavelength light waves, thereby greatly reducing the direct damage of UV rays to the polyurethane film. This means that even in long-term outdoor or high UV intensity environments, the high temperature resistant film composition can still maintain excellent physical properties and color stability, significantly extending its service life.

[0044] In some embodiments, the method for preparing the polyisocyanate comprises: heating the mixture of the polycaprolactone and the ultraviolet absorber to 100-120° C., removing water in vacuo, cooling to 75-85° C., adding the isophorone diisocyanate, and reacting at a constant temperature until the hydroxyl value reaches 27-31 mgKOH / g.

[0045] By heating the mixture of polycaprolactone and UV absorber to a precise temperature range of 100-120°C, this step ensures the full melting and mixing of the raw materials while avoiding unnecessary thermal degradation or side reactions caused by excessively high temperatures. Subsequently, the next step is carried out in a cooling range of 75-85°C. Such a temperature gradient treatment helps control the reaction rate and promotes uniform contact and reaction between the reactants, thereby improving the uniformity and stability of the final product.

[0046] Vacuum dehydration can effectively remove moisture from raw materials, preventing moisture from participating as a by-product in subsequent reactions, thereby affecting the quality and performance of the product.

[0047] In some embodiments, the high temperature resistant membrane further comprises the following components calculated by weight: 0.4-3 parts of a catalyst.

[0048] The catalyst is at least one of BCAT-E16, CUCAT-HAB, ZCAT-EZ19 and BCAT-E20CX produced by Guangzhou Yourun Synthetic Materials Co., Ltd.

[0049] In the composition formula of high temperature resistant film, these catalysts can help polyols and isocyanates and other raw materials react better through their unique catalytic effect to form a uniform interpenetrating network structure, thereby improving the mechanical properties, light transmittance and aging resistance of the product. At the same time, they can also promote the dispersion and dissolution of additives to a certain extent, ensuring that the components in the composition can be fully mixed and evenly exert synergistic effects.

[0050] In some embodiments, the high temperature resistant film further comprises the following components calculated by weight: 1-5 parts of a surfactant.

[0051] The surfactant is at least one of 10366, L3002 and L580 produced by MOMEN IT IVE.

[0052] Surfactants, with their excellent wetting and dispersing properties, can effectively improve the uniformity of raw materials during the mixing process, ensuring that the surface of the film is smoother and more delicate after coating. This not only improves the appearance quality of the film material, but also provides a good foundation for subsequent processing and use.

[0053] In some embodiments, the high temperature resistant film further comprises the following components calculated by weight: 0.1-2 parts of light stabilizer.

[0054] The light stabilizer is selected from one or more of YI STAB292, YI NOX235, YIPHOS2105 and YI STABUV-1 of Nanxiong Zhiyi Fine Chemical Co., Ltd. Preferably, the light stabilizer is a methylamine light stabilizer or a hindered amine light stabilizer.

[0055] The addition of light stabilizers, especially methylamine and hindered amine light stabilizers, can effectively absorb or reflect harmful light waves under long-term ultraviolet radiation, thereby greatly delaying the yellowing process of the material. This not only extends the service life of the high-temperature resistant film, but also ensures its aesthetics and functionality in outdoor or high-light environments.

[0056] The present application also proposes a method for preparing a high temperature resistant film, comprising mixing the raw material components of any of the above-mentioned high temperature resistant films in proportion, coating the mixed raw materials on a substrate, and drying the substrate.

[0057] In some embodiments, the stirring speed is 25-35 r / min, the stirring temperature is 25-35°C; the drying temperature is: 100°C in the front section, 130°C in the middle section, and 130°C in the back section.

[0058] The drying temperature design of 100℃ in the front section, 130℃ in the middle section, and 130℃ in the back section fully considers the curing requirements of raw materials at different stages. The low-temperature preheating in the front section helps the initial volatilization of the solvent, and the high temperature in the middle and back sections accelerates the completion of the chemical reaction and the curing of the film, ensuring the density and uniformity of the film structure. The staged heating method not only improves the drying efficiency, but also reduces defects such as cracking or deformation of the film layer caused by excessive temperature, ensuring the appearance quality and mechanical properties of the product.

[0059] The raw materials and equipment used in this application, unless otherwise specified, are all commonly used raw materials and equipment in the art; the methods used in this invention, unless otherwise specified, are all conventional methods in the art.

[0060] Unless otherwise specified, the meanings of the terms in this specification are the same as those generally understood by those skilled in the art. However, if there is any conflict, the definitions in this specification shall prevail.

[0061] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0062] It should be noted that the chain extenders, ultraviolet absorbers, catalysts, surfactants and light stabilizers in the present application can be selected and replaced by those skilled in the art according to the components disclosed in the present application or the components commonly used in the art. Only one of them is selected for example in the embodiments and comparative examples of the present application, and the present application will not elaborate on them here.

[0063] The preparation methods of the polyisocyanate in the embodiments and comparative examples are as follows: in the polyisocyanate, a mixture of 25.5 parts of polycaprolactone and 0.6 parts of 2,4-dihydroxybenzophenone, calculated by weight, is heated to 110° C., after vacuum removal of water, the temperature is lowered to 80° C., 100 parts of isophorone diisocyanate are added, and the mixture is reacted at a constant temperature until the hydroxyl value reaches 29 mgKOH / g.

[0064] The specific preparation methods of the high temperature resistant films in the embodiments and comparative examples are: according to the raw material formula, polyols and additives are added to the batching reactor in sequence, and the raw materials are mixed evenly; the mixed raw materials, namely P material and polyisocyanate, namely I material, are added to the storage tank in sequence, the temperature is set to 30°C, and the stirring speed of the batching reactor is 30r / min; the machine head needs to use a servo vacuum stirring head, the discharge rate is 50g / s, and the ratio of P material to I material is 100:70; the substrate is coated by a coating machine, the coating machine uses a comma scraper, and the thickness is set to 0.1MM; after coating, it is placed in an oven for drying, and the oven temperature is: 100°C for the front section, 130°C for the middle section, and 130°C for the rear section.

[0065] In the QACFT006-2023 test method in the embodiments and comparative examples:

[0066] Blank impact force peak: The impact energy loaded on the thin flexible material during the test, the maximum impact force peak, in N.

[0067] Impact force peak value: The maximum impact force peak value after the impact energy loaded on the thin flexible material during the test is buffered by the buffer material product, the unit is N.

[0068] Energy absorption rate: the ratio of the peak impact force absorbed by a thin flexible material to the peak impact force of a blank material, expressed in %.

[0069] Principle: Place the test sample on a smooth, burr-free 45# steel test anvil, use a steel ball of a certain mass and diameter to drop freely from a certain height onto the test sample, and the sensor under the anvil acquires data.

[0070] Test equipment and materials: 1. Steel ball: a stainless steel ball with a smooth surface, diameter (20±0.1) mm, weight (32.5±0.3) g. 2. Film impact tester: equipped with an automatic plotter to record the relationship between force and time. The tester is equipped with a 45# steel anvil, connected to an accelerometer, with a range of 10000g, a sensitivity of 0.05mV / g, and a frequency response of 1-10000Hz. 3. Thickness gauge: should comply with the relevant provisions of GB / T 6672.

[0071] Sample and conditioning environment: The sample thickness should be uniform and the surface should be flat. The sample should meet the requirements that the distance between each measuring point and the edge of the sample is not less than 15mm, the distance between each measuring point is not less than 15mm, and each sample should be measured at no less than 5 points.

[0072] Before testing, the prepared samples should be placed in a temperature condition that meets the reference standard environment in GB / T 2918 for at least 24 hours. Other temperatures may be selected for testing after negotiation between the two parties.

[0073] Test steps: Place the adjusted sample on the test anvil to ensure that the sample is flat and free of bubbles. Drop a steel ball from a high altitude onto the test sample to ensure that the steel ball falls to the center of the anvil.

[0074] After testing five points, observe the integrity of the material and record the maximum impact force peaks at five points of the specimen.

[0075] Example 1

[0076] A high temperature resistant film, calculated by weight, comprises the following components:

[0077] raw material Dosage Trihydroxy Polyoxypropylene Ether 83 Polytetramethyl ether glycol 10 Polypropylene carbonate glycol 7 Polyisocyanate 70 BCAT-E16 0.8 L3002 3 1,3-Butanediol 5 YIPHOS2105 2

[0078] Test results:

[0079]

[0080] Example 2

[0081] A high temperature resistant film, calculated by weight, comprises the following components:

[0082] raw material Dosage Trihydroxy Polyoxypropylene Ether 80 Polytetramethyl ether glycol 10 Polypropylene carbonate glycol 10 Polyisocyanate 70 BCAT-E16 0.8 L3002 3 1,3-Butanediol 5 YIPHOS2105 2

[0083] Test results:

[0084]

[0085] Example 3

[0086] A high temperature resistant film, calculated by weight, comprises the following components:

[0087] raw material Dosage Trihydroxy Polyoxypropylene Ether 75 Polytetramethyl ether glycol 10 Polypropylene carbonate glycol 15 Polyisocyanate 70 BCAT-E16 0.6 L3002 3 1,3-Butanediol 5 YIPHOS2105 2

[0088] Test results:

[0089]

[0090] Comparative Example 1

[0091] A high temperature resistant film, calculated by weight, comprises the following components:

[0092] raw material Dosage Polytetramethyl ether glycol 50 Polypropylene carbonate glycol 50 Polyisocyanate 70 BCAT-E16 0.8 L3002 3 1,3-Butanediol 5 YIPHOS2105 2

[0093] Test results:

[0094]

[0095] Comparative Example 2 A high temperature resistant film, calculated by weight, comprises the following components:

[0096] raw material Dosage Trihydroxy Polyoxypropylene Ether 88 Polypropylene carbonate glycol 12 Polyisocyanate 70 BCAT-E16 0.8 L3002 3 1,3-Butanediol 5 YIPHOS2105 2

[0097] Test results:

[0098]

[0099] Comparative Example 3 A high temperature resistant film, calculated by weight, comprises the following components:

[0100] raw material Dosage Trihydroxy Polyoxypropylene Ether 88 Polytetramethyl ether glycol 12 Polyisocyanate 70 BCAT-E16 0.6 L3002 3 1,3-Butanediol 5 YIPHOS2105 2

[0101] Test results:

[0102] In the test results of Comparative Examples 1-3, the energy absorption rates are all lower than those of Examples 1-3. Comparative Examples 1-3 lack any one of trihydroxy polyoxypropylene ether, polytetramethyl ether glycol and polypropylene carbonate glycol, and the finished products fail to form the three-dimensional interpenetrating network in Examples 1-3. The molecular chains are mostly flexible long chains, and the intermolecular hindrance is small when impacted by external forces, and the molecular chains will slip and stretch. The lack of hindrance of the side chains results in poor energy absorption in the macroscopic performance.

[0103] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0104] The above-described embodiments only express several embodiments of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A high temperature resistant film, characterized in that: The high temperature resistant film comprises the following components calculated by weight:

2. The high temperature resistant film according to claim 1, characterized in that: The trihydroxy polyoxypropylene ether, polytetramethyl ether diol and polypropylene carbonate diol are a polyol mixture, and the total weight of the polyisocyanate is 50%-80% of the total weight of the other components in the high temperature resistant film.

3. The high temperature resistant film according to claim 2, characterized in that: The polyisocyanate comprises the following components calculated by weight: 20-30 parts of polycaprolactone and 90-110 parts of isophorone diisocyanate.

4. The high temperature resistant film according to claim 3, characterized in that: The polyisocyanate further comprises the following components by weight: 0.5-1 part of ultraviolet absorber.

5. The high temperature resistant film according to claim 4, characterized in that: The preparation method of the polyisocyanate comprises: heating the mixture of the polycaprolactone and the ultraviolet absorber to 100-120° C., removing water in vacuo, cooling to 75-85° C., adding the isophorone diisocyanate, and reacting at a constant temperature until the hydroxyl value reaches 27-31 mgKOH / g.

6. The high temperature resistant film according to claim 1, characterized in that: The high temperature resistant membrane further comprises the following components calculated by weight: 0.4-3 parts of catalyst.

7. The high temperature resistant film according to claim 1, characterized in that: The high temperature resistant film further comprises the following components calculated by weight: 1-5 parts of surfactant.

8. The high temperature resistant film according to claim 1, characterized in that: The high temperature resistant film further comprises the following components calculated by weight: 0.1-2 parts of light stabilizer.

9. A method for preparing a high temperature resistant film, characterized in that: The method comprises stirring and mixing the raw material components of the high temperature resistant film according to any one of claims 1 to 8 in proportion, coating the mixed raw materials on a substrate, and drying the substrate.

10. The method for preparing a high temperature resistant film according to claim 9, characterized in that: The stirring speed is 25-35r / min, the stirring temperature is 25-35℃; the drying temperature is: 100℃ in the front section, 130℃ in the middle section, and 130℃ in the back section.

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