Preparation method of high-thermal-stability polymer micro-nano structure

Abstract

The application discloses a preparation method of a high-thermal-stability high-molecular micro-nano structure, which comprises the following steps: preparing a solution by taking polyethylene oxide as raw material and toluene as solvent; preparing a polyethylene oxide ultrathin film sample by adopting a spin coating method; firstly, performing melt isothermal crystallization on the polyethylene oxide ultrathin film sample under a nitrogen protection atmosphere, wherein the crystallization temperature is T c1 , and the crystallization time is t c1 ; and then, further increasing the crystallization temperature to T c2 , continuing crystallization for t c2 ; and the micro-nano structure constructed by the method has high thermal stability, the thermal stability of the polymer ultrathin film is controlled from the nanometer scale, and the application of the polymer ultrathin film in the fields of sensors, thermal etching, drug release and the like is widened.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of polymer processing, and relates to a preparation method of high-thermal-stability polymer micro-nano structure. BACKGROUND

[0002] Polymer thin films are applied in various fields of modern science and technology, such as liquid crystal display, photoetching, data storage, sensor, anti-reflection coating and drug release. In the polymer thin film system, due to the influence of space limitation and interface effect, the crystallization morphology structure is quite different from that of the bulk. The preparation of high-thermal-stability micro-nano structure helps to improve the thermal stability of the thin film and widen the application range of the polymer thin film in various fields.

[0003] Polyethylene oxide, also known as polyethylene oxide, is abbreviated as PEO, and its structural formula is (CH2CH2O) n PEO is a green degradable linear polymer with good crystallinity, thermoplasticity and water solubility.

[0004] The polyethylene oxide thin film is first crystallized at low temperature and then further crystallized at high temperature to form lamellar micro-nano structure with a “self-constrained” structure. The thinner lamellar structure formed at low temperature is in an “overheated state” under the protection of the thicker lamellar structure formed at high temperature, and therefore has high thermal stability. SUMMARY

[0005] The application provides a preparation method of high-thermal-stability polymer micro-nano structure. The method first prepares a thin film by spin coating a polyethylene oxide solution. The polyethylene oxide ultrathin film sample is first subjected to melt isothermal crystallization under a nitrogen protective atmosphere, the crystallization temperature is T c1 , the crystallization time is t c1 , the crystallization temperature is further increased to T c2 , and the crystallization is continued for t c2 , to obtain lamellar micro-nano structure with a “self-constrained” structure. The thermal stability of the polymer ultrathin film is regulated at the nanoscale, and the application of the polymer ultrathin film in the fields of sensor, thermal etching and drug release is widened.

[0006] The technical scheme of the application is as follows: a preparation method of high-thermal-stability polymer micro-nano structure, characterized by comprising the following steps:

[0007] Step 1: surface treatment is performed on a silicon wafer;

[0008] Step 2: polyethylene oxide raw materials are weighed, and a solution is prepared by using toluene as a solvent;

[0009] Step 3: the solution is placed on a hot stage and heated until the solute is fully dissolved;

[0010] Step 4: using the treated silicon wafer as a substrate, a thin film is prepared by spin coating with a spin coater;

[0011] Step 5: the prepared polyethylene oxide thin film sample is placed on an atomic force microscope hot stage together with the substrate silicon wafer, melt isothermal crystallization and further temperature crystallization are carried out under a nitrogen protective atmosphere, the crystallization temperature of the melt isothermal crystallization is Tc1, the crystallization time is tc1, and the further temperature crystallization is further increased to T c2 , the crystallization time is t c2 , and a high-thermal-stability polymer micro-nano structure is obtained.

[0012] Further, in step 1, the surface treatment of the silicon wafer is ultraviolet ozone treatment for 40 min.

[0013] Further, in step 2, the polyethylene oxide has a number average molecular weight of 20 kg / mol, and the prepared solution has a mass fraction of 0.35%.

[0014] Further, in step 3, the prepared solution is heated in a hot stage at 70 DEG C for 30 min to fully dissolve the solute.

[0015] Further, in step 4, the spin film conditions of the spin coater are: spin coating at 3000 rpm for 30 s.

[0016] Further, in step 4, the specific process of melt isothermal crystallization is: the polyethylene oxide ultra-thin film is heated at a heating rate of 7 DEG C / min~10 DEG C / min from 25 DEG C to 62.7 DEG C, kept at 62.7 DEG C for 1 min, then cooled at a cooling rate of 7 DEG C / min~10 DEG C / min from 62.7 DEG C to 59 DEG C, and isothermally crystallized at 59 DEG C for 120 min.

[0017] Further, in step 4, the specific process of further temperature crystallization is: further increasing the temperature to 61 DEG C, and crystallizing at 61 DEG C for 30~120 min.

[0018] Further, in step 4, the thermal stability of the polyethylene oxide micro-nano structure is compared and judged by melting, and the lamellar morphology evolution during melting is characterized by atomic force microscopy.

[0019] Further, the melting process is to continue to increase the temperature of the hot stage to 62.5 DEG C.

[0020] The beneficial effects of the present application are:

[0021] The application provides a preparation method of high-thermal-stability polymer micro-nano structure, which controls the thermal stability of a polymer ultrathin film from a nanometer scale, and widens the application of the polymer ultrathin film in the fields of sensors, thermal etching, drug release and the like.

[0022] In order to make the above and other objects, features and advantages of the present application more apparent, the following will give a detailed description of preferred embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description are only some of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0024] Figure 1 Figure 1 is a height map of morphological evolution during in-situ melting of the lamellae with the isothermal crystallization in Example 1.

[0025] Figure 2 Figure 2 is a height map of morphological evolution during in-situ melting of the lamellae with the “self-constrained” structure in Example 2.

[0026] Figure 3 Figure 3 is a height map of morphological evolution during in-situ melting of the lamellae with the “self-constrained” structure in Example 3.

[0027] Figure 4 Figure 4 is a height map of morphological evolution during in-situ melting of the lamellae with the “self-constrained” structure in Example 4. IMPLEMENTATION

[0028] The following examples are used to illustrate the present application, but not to limit the protection scope of the present application. It should be understood that each step recorded in the method implementation of the present application can be executed in different order. In addition, the method implementation can include additional steps or omit the steps shown, and if not specifically indicated, the technical means used in the examples is the conventional means familiar to those skilled in the art.

[0029] In the embodiments of the present application, the silicon wafer is P100 type silicon wafer from Zhejiang Lijing Optoelectronics Technology Co., Ltd., the ultraviolet oxidation lamp is 30W double U type sterilization ultraviolet lamp from Hangtian Hongda, the hot stage is JF-956s type, the glue spreading machine is KW-4A type glue spreading machine from Chinese Academy of Sciences Microelectronics Institute, and the polyethylene oxide is purchased from Sigma-Aldrich Company in the United States.

[0030] In the embodiments of the present application, the judgment and comparison of the thermal stability of the micro-nano structure is realized by placing it on a hot stage for melting, and then performing morphology characterization by an atomic force microscope. Embodiment

[0031] A preparation method of a high-thermal-stability polymer micro-nano structure, steps are as follows:

[0032] Step 1: surface treatment of a silicon wafer: a P100 type silicon wafer with a size of 1 cm x 1 cm is oxidized by ozone generated by ultraviolet light irradiation for 40 min.

[0033] Step 2: a polyethylene oxide with a number average molecular weight of 20 kg / mol is selected as a raw material, and toluene is used as a solvent to prepare a solution with a mass fraction of 0.35%.

[0034] Step 3: the blended solution is placed in a hot stage at 70°C and heated for 30 min until the solute is completely dissolved.

[0035] Step 4: using a spin coater, the surface-treated silicon wafer is used as a substrate, and the speed is rotated at 3000 revolutions per second for 30 seconds to prepare a thin film, and a polyethylene oxide thin film with a thickness of about 10 nm is obtained.

[0036] Step 5: the prepared polyethylene oxide thin film sample is placed on an atomic force hot stage, and isothermal crystallization is carried out under a nitrogen protective atmosphere, and the specific temperature program is as follows: under a nitrogen protective atmosphere, the polyethylene oxide ultra-thin film is heated from 25°C to 62.7°C at a heating rate of 7°C / min to 10°C / min, and then cooled from 62.7°C to 59°C at a cooling rate of 7°C / min to 10°C / min, and then isothermally crystallized at 59°C for 120 min.

[0037] Step 6: the thermal stability is compared and judged by melting, and the temperature of the hot stage is further increased to 62.5°C, and the morphology evolution during the melting process is in-situ characterized by atomic force microscopy. Embodiment

[0038] A preparation method of a high-thermal-stability polymer micro-nano structure, steps are as follows:

[0039] Step 1: surface treatment of a silicon wafer: a P100 type silicon wafer with a size of 1 cm x 1 cm is oxidized by ozone generated by ultraviolet light irradiation for 40 min.

[0040] Step 2: a polyethylene oxide with a number average molecular weight of 20 kg / mol is selected as a raw material, and toluene is used as a solvent to prepare a solution with a mass fraction of 0.35%.

[0041] Step 3: the blended solution is placed in a hot stage at 70°C and heated for 30 min until the solute is completely dissolved.

[0042] Step 4: The surface-treated silicon wafer was used as a substrate, and a film was prepared by rotating the spin coater at 3000 rpm for 30 seconds to obtain a polyethylene oxide film with a thickness of about 10 nm.

[0043] Step 5: The prepared polyethylene oxide film sample was placed on an atomic force thermal stage and subjected to melt crystallization under a nitrogen protective atmosphere. The specific temperature program was as follows: under a nitrogen protective atmosphere, the polyethylene oxide ultra-thin film was heated from 25°C to 62.7°C at a heating rate of 7°C / min to 10°C / min, kept at 62.7°C for 1 min, then cooled from 62.7°C to 59°C at a cooling rate of 7°C / min to 10°C / min, and crystallized at 59°C for 120 min; further increased the temperature to 61°C, and crystallized at 61°C for 30 min.

[0044] Step 6: The thermal stability was compared and judged by melting, and the temperature of the thermal stage was further increased to 62.5°C, and the morphology evolution during melting was in-situ characterized by atomic force microscopy. Embodiment

[0045] A method for preparing a high-thermal-stability polymer micro-nano structure, comprising the following steps:

[0046] Step 1: Surface treatment of silicon wafer: a P100 type silicon wafer with a size of 1 cm x 1 cm was oxidized by ozone generated by ultraviolet light for 40 min.

[0047] Step 2: Polyethylene oxide with a number average molecular weight of 20 kg / mol was selected as the raw material, and toluene was used as the solvent to prepare a solution with a mass fraction of 0.35%.

[0048] Step 3: The blended solution was heated in a thermal stage at 70°C for 30 min until the solute was completely dissolved.

[0049] Step 4: The surface-treated silicon wafer was used as a substrate, and a film was prepared by rotating the spin coater at 3000 rpm for 30 seconds to obtain a polyethylene oxide film with a thickness of about 10 nm.

[0050] Step 5: The prepared polyethylene oxide film sample was placed on an atomic force thermal stage and subjected to melt crystallization under a nitrogen protective atmosphere. The specific temperature program was as follows: under a nitrogen protective atmosphere, the polyethylene oxide ultra-thin film was heated from 25°C to 62.7°C at a heating rate of 7°C / min to 10°C / min, kept at 62.7°C for 1 min, then cooled from 62.7°C to 59°C at a cooling rate of 7°C / min to 10°C / min, and crystallized at 59°C for 120 min; further increased the temperature to 61°C, and crystallized at 61°C for 30 min.

[0051] Step 6: The thermal stability is compared and judged by melting, and the temperature of the hot stage is continuously increased to 62.5℃, and the morphology evolution in the melting process is in-situ characterized by an atomic force microscope. Embodiment

[0052] A preparation method of a high-thermal-stability polymer micro-nano structure, steps are as follows:

[0053] Step 1: Surface treatment of a silicon wafer: a P100 type silicon wafer with a size of 1cm*1cm is oxidized for 40min by using ozone generated by ultraviolet light irradiation.

[0054] Step 2: A polyethylene oxide with a number average molecular weight of 20kg / mol is selected as a raw material, and toluene is used as a solvent to prepare a solution with a mass fraction of 0.35%.

[0055] Step 3: The blended solution is placed in a hot stage at 70℃ and heated for 30min until the solute is completely dissolved.

[0056] Step 4: A silicon wafer with surface treatment is used as a substrate, and a thin film is prepared by rotating the film at a speed of 3000rpm for 30s using a film applicator, and a polyethylene oxide thin film with a thickness of about 10nm is obtained.

[0057] Step 5: The prepared polyethylene oxide thin film sample is placed on an atomic force hot stage, and melting and crystallization are carried out under a nitrogen protective atmosphere, and the specific temperature program is as follows: the polyethylene oxide ultra-thin film is heated from 25℃ to 62.7℃ at a heating rate of 7℃ / min~10℃ / min under a nitrogen protective atmosphere, and then cooled from 62.7℃ to 59℃ at a cooling rate of 7℃ / min~10℃ / min, and then crystallized at 59℃ for 120min; further increase the temperature to 61℃, and crystallize at 61℃ for 120min.

[0058] Step 6: The thermal stability is compared and judged by melting, and the temperature of the hot stage is continuously increased to 62.5℃, and the morphology evolution in the melting process is in-situ characterized by an atomic force microscope.

[0059] Note that the above is only the preferred embodiment of the present application and the technical principle applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments herein, and those skilled in the art can make various obvious changes, re-adjustments and substitutions without departing from the scope of the present application. Therefore, although the present application has been described in more detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the appended claims.

Claims

1. A method for preparing a high thermal stability polymer micro-nanostructure, characterized in that: The method comprises the following steps: Step 1: Surface treatment of silicon wafer; Step 2: Weigh the polyethylene oxide raw material and prepare a solution using toluene as solvent; Step 3: Heat the solution on a hot plate until the solute is fully dissolved; Step 4: Using the treated silicon wafer as the substrate, a thin film is prepared by spin coating using a spin coater; Step 5: placing the prepared polyethylene oxide film sample together with the substrate silicon wafer on an atomic force microscope hot stage, and performing melt isothermal crystallization and further elevated temperature crystallization under a nitrogen atmosphere, wherein the crystallization temperature of the melt isothermal crystallization is Tc1 and the crystallization time is tc1; the further elevated temperature crystallization is to further increase the crystallization temperature to Tc2 on the basis of the melt isothermal crystallization, and the crystallization time is tc2, thereby obtaining a polymer micro-nanostructure with high thermal stability; In step 5, the specific process of melt isothermal crystallization is as follows: heating the polyethylene oxide ultra-thin film from 25°C to 62.7°C at a heating rate of 7°C / min to 10°C / min, keeping the temperature at 62.7°C for 1 minute, then cooling the temperature from 62.7°C to 59°C at a cooling rate of 7°C / min to 10°C / min, and isothermal crystallizing at 59°C for 120 minutes; In step 5, the specific process of further heating and crystallizing is: further raising the temperature to 61° C. and crystallizing at 61° C. for 30 to 120 minutes.

2. The method for preparing a high thermal stability polymer micro-nanostructure according to claim 1, characterized in that: In step 1, the surface of the silicon wafer is treated with ultraviolet ozone for 40 minutes.

3. The method for preparing a high thermal stability polymer micro-nanostructure according to claim 1, characterized in that: In step 2, the number average molecular weight of the polyethylene oxide is 20 kg / mol, and the mass fraction of the prepared solution is 0.35%.

4. The method for preparing a high thermal stability polymer micro-nanostructure according to claim 1, characterized in that: In step 3, the prepared solution is placed on a hot plate at 70° C. and heated for 30 minutes to fully dissolve the solute.

5. The method for preparing a high thermal stability polymer micro-nanostructure according to claim 1, characterized in that: In step 4, the spin coating condition of the spin coater is: spin coating at 3000 rpm for 30 seconds.

6. The method for preparing a high thermal stability polymer micro-nanostructure according to claim 1, characterized in that: In step 5, the thermal stability of the polyethylene oxide micro-nanostructure is compared and judged by a melting method, and the evolution of the lamellae morphology during the melting process is characterized by an atomic force microscope.

7. The method for preparing a high thermal stability polymer micro-nanostructure according to claim 6, characterized in that: The melting process is to continue to increase the temperature of the hot stage to 62.5°C.

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