Ultrasonic compression molding apparatus and molding method for preparing polymer surface microstructure

Abstract

The application belongs to the technical field of polymer surface microstructure, and particularly relates to an ultrasonic plastic pressing forming device and a forming method for preparing a polymer surface microstructure. The ultrasonic plastic pressing forming device comprises an ultrasonic mechanism and a die mechanism. The ultrasonic mechanism comprises a driving member and an ultrasonic punch. The driving member is connected with the ultrasonic punch to drive the ultrasonic punch to vibrate ultrasonically. The die mechanism comprises a top die and a die plate assembly. The ultrasonic punch and the die plate assembly are respectively located at opposite sides of the top die. The die plate assembly is provided with a die plate cavity. The top die is provided with a punching hole for accommodating the ultrasonic punch and a communication hole for communicating the punching hole and the die plate cavity. The communication hole is located between the punching hole and the die plate cavity. The diameter of the punching hole is greater than the diameter of the communication hole, so that a step surface is formed between the punching hole and the communication hole. The step surface is provided with a raw material groove for accommodating polymer master batches. The ultrasonic plastic pressing forming device is beneficial to large-scale, low-cost and high-quality preparation of polymer surface microstructures with multiple levels and high aspect ratios.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of polymer surface microstructure, and particularly relates to an ultrasonic plastic pressing forming device and a forming method for preparing a polymer surface microstructure. BACKGROUND

[0002] The polymer surface microstructure has excellent optical and biological properties and is widely used in the fields of optoelectronic engineering, biomedical engineering, micro-electro-mechanical system, energy and environmental protection, etc. The polymer surface microstructure parts bring great challenges to large-scale processing and manufacturing due to the requirements of small structure size and high precision. The ultrasonic imprinting and ultrasonic plasticizing micro-injection molding are ideal methods for manufacturing the polymer surface microstructure parts, which rapidly plasticize the polymer by using ultrasonic vibration, and the equipment is simple, the forming time is short, and the cost is low.

[0003] For the ultrasonic imprinting, the microstructure of the template is easily deformed or even damaged due to the severe friction between the polymer master batch or polymer substrate and the microstructure of the template under ultrasonic vibration, and the template is limited to high-strength and high-hardness materials. For the ultrasonic micro-imprinting of polymer powder, the melting of the upper powder blocks the transmission of ultrasonic vibration, so that the lower powder cannot be melted, and therefore, the microstructure with high aspect ratio cannot be formed. For the ultrasonic plasticizing micro-injection molding, the ultrasonic vibration is mainly used to replace the heat source and screw in the micro-injection molding process to plasticize the polymer, and the role of ultrasonic vibration is not fully played, and the filling capacity of the melt to the nanoscale micro-pores is insufficient. Therefore, the forming quality of the polymer surface microstructure prepared by the above methods is not high, and especially, the nanoscale polymer surface microstructure with high aspect ratio cannot be prepared in high quality. SUMMARY

[0004] The purpose of the embodiments of the application is to provide an ultrasonic plastic pressing forming device and a forming method for preparing a polymer surface microstructure, which can solve the problem of low forming quality of the polymer surface microstructure in the related art.

[0005] The technical scheme adopted by the embodiments of the application is as follows:

[0006] In a first aspect, an ultrasonic plastic pressing forming device suitable for preparing a polymer surface microstructure is provided, which comprises an ultrasonic mechanism and a die mechanism. The ultrasonic mechanism comprises a driving member and an ultrasonic punch, and the driving member is connected with the ultrasonic punch to drive the ultrasonic punch to vibrate ultrasonically. The die mechanism comprises an upper die and a template assembly, and the ultrasonic punch and the template assembly are respectively located at opposite sides of the upper die. The template assembly is provided with a template cavity. The upper die is provided with a pressing hole for accommodating the ultrasonic punch and a communication hole for communicating the pressing hole and the template cavity, and the communication hole is located between the pressing hole and the template cavity. The diameter of the pressing hole is greater than the diameter of the communication hole, so that a step surface is formed between the pressing hole and the communication hole, and the step surface is provided with a raw material groove for accommodating a polymer master batch.

[0007] Optionally, the raw material groove is annularly arranged at the outer circumferential side of the communication hole.

[0008] Optionally, the groove depth of the raw material groove is in the range of 0.1mm-0.5mm.

[0009] Optionally, the projection of the ultrasonic punch on a plane perpendicular to the axis of the stamping hole covers the projection of the template cavity on the plane perpendicular to the axis of the stamping hole.

[0010] Optionally, the template assembly comprises a bottom die and at least one template, each template being located between the top die and the bottom die, each template being provided with a through hole, and the through holes of each template collectively forming the template cavity; the through hole of the template adjacent to the top die is in communication with the communication hole, and the bottom die is used to seal the through hole of the template adjacent to the bottom die.

[0011] Optionally, the number of templates is multiple, and the top die, the multiple templates and the bottom die are sequentially and closely connected.

[0012] In a second aspect, a forming method for preparing a polymer surface microstructure is provided, which uses the ultrasonic plastic pressing forming device described above, and comprises the following steps:

[0013] Loading: placing the polymer master batch in the raw material groove;

[0014] Starting ultrasonic vibration: inserting the ultrasonic punch into the stamping hole, and then starting the driving member to drive the ultrasonic punch to ultrasonically vibrate and extrude the polymer master batch, so that the polymer master batch is plasticized and melted to form a polymer melt; and under the ultrasonic vibration and pressing of the ultrasonic punch, the polymer melt flows into the template cavity through the communication hole;

[0015] Stopping ultrasonic vibration: after the template cavity is filled to a preset state, stopping the ultrasonic vibration of the ultrasonic punch.

[0016] Demolding: after the polymer melt is cooled and formed into a polymer surface microstructure, the polymer surface microstructure is taken out.

[0017] Optionally, in the step of loading, the raw material groove is annularly arranged at the outer circumferential side of the communication hole, and the polymer master batch is uniformly loaded in the raw material groove, so that the polymer master batch is uniformly annularly arranged at the outer circumferential side of the communication hole.

[0018] Optionally, in the step of stopping ultrasonic vibration, after stopping the ultrasonic vibration of the ultrasonic punch, the ultrasonic punch is pressed against the polymer melt and gives the polymer melt a preset pressure.

[0019] Optionally, the vibration frequency of the ultrasonic punch is greater than 20kHz.

[0020] The ultrasonic plastic compression molding device and the molding method for preparing polymer surface microstructure provided by the application have at least one of the following technical effects: in the preparation process of the polymer microstructure, the polymer master batch is melted in the raw material groove, so that the polymer master batch is prevented from rubbing against the template cavity violently, the damage to the template assembly is reduced, the template assembly is conducive to repeated use, and the template assembly can also use materials with lower strength and hardness, thereby reducing the manufacturing cost of the ultrasonic plastic compression molding device; the ultrasonic punch and the template assembly are located on opposite sides of the top die, so that the polymer melt can also be subjected to the ultrasonic vibration of the ultrasonic punch, thereby reducing the viscosity of the polymer melt, and the template cavity of the template can also have a certain surface temperature, the flowability and filling capacity of the polymer melt are improved, the polymer melt can flow into the microstructure with smaller size and deeper depth in the template cavity, and the molding quality of the polymer surface microstructure is further improved; meanwhile, under the continuous action of ultrasonic vibration, the residual air in the polymer melt is beneficial to be removed, the formation of air bubbles is reduced, and the molding quality of the polymer surface microstructure is further improved; the ultrasonic plastic compression molding device has simple structure, low manufacturing cost and good molding quality, and is conducive to realizing large-scale, low-cost and high-quality preparation of polymer surface microstructures with multiple levels and high aspect ratio.

[0021] The above description is only a summary of the technical solutions of the application. In order to more clearly understand the technical means of the application, the application can be implemented according to the content of the specification, and in order to make the above and other purposes, characteristics and advantages of the application more obvious and easy to understand, the following specific embodiments of the application are described. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0023] Figure 1 The cross-sectional view of the ultrasonic plastic compression molding device provided by an embodiment of the application loaded with polymer master batch.

[0024] Figure 2 For Figure 1 The structural schematic view of the ultrasonic plastic compression molding device hiding the ultrasonic device.

[0025] Figure 3 The principle schematic view of preparing polymer surface microstructure by using the ultrasonic plastic compression molding device provided by another embodiment of the application.

[0026] Figure 4A schematic diagram of a principle of preparing a polymer surface microstructure by using an ultrasonic plastic compression forming device is provided for another embodiment of the present application.

[0027] Figure 5 A schematic diagram of a principle of preparing a polymer surface microstructure by using an ultrasonic plastic compression forming device is provided for another embodiment of the present application.

[0028] Figure 6 A schematic diagram of a principle of preparing a polymer surface microstructure by using an ultrasonic plastic compression forming device is provided for another embodiment of the present application.

[0029] In the drawings, various elements are labeled the same as follows:

[0030] 100, ultrasonic plastic compression forming device; 110, ultrasonic mechanism; 111, driving member; 1111, ultrasonic generator; 1112, ultrasonic transducer; 112, ultrasonic punch; 120, mold mechanism; 121, top mold; 1211, stamping hole; 1212, communication hole; 1213, stepped surface; 1214, raw material groove; 122, mold plate assembly; 1221, bottom mold; 1222, mold plate; 12221, first-level mold plate; 1222, second-level mold plate; 12223, third-level mold plate; 1223, mold plate cavity; 12231, through hole; 130, powder particles; 200, polymer surface microstructure; 300, polymer master batch; DETAILED DESCRIPTION

[0031] In order to make the technical problems to be solved by the present application, technical solutions and beneficial effects clearer, the following will be further described in detail in combination with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not intended to limit the present application. Figures 1-6 The specific embodiments described herein are only used to explain the present application, and are not intended to limit the present application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application; the terms "include" and "have" and any variations thereof used herein are intended to cover a non-exclusive inclusion.

[0033] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features.

[0034] Reference to“an embodiment” herein means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase“in an embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. It is expressly understood that any of the embodiments described herein can be incorporated in a variety of embodiments of the application.

[0035] In the description of the embodiments of the application, the term“and / or” only means an association relationship of the associated objects, which can mean that there are three relationships, for example, A and / or B, which can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character“ / ” herein generally means that the front and rear associated objects are in an“or” relationship.

[0036] In the description of the embodiments of the application, the term“a plurality of” means two or more (including two), and similarly, “a plurality of groups” means two or more groups (including two groups), and “a plurality of pieces” means two or more pieces (including two pieces). The meaning of“several” is one or more, unless otherwise explicitly specified.

[0037] In the description of the embodiments of the application, the technical terms“center”,“longitudinal”,“transverse”,“length”,“width”,“thickness”,“upper”,“lower”,“front”,“rear”,“left”,“right”,“vertical”,“horizontal”,“top”,“bottom”,“inner”,“outer”,“clockwise”,“counterclockwise”,“axial”,“radial”,“circumferential” and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the embodiments of the application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the application.

[0038] In the description of the embodiments of the application, unless otherwise explicitly specified and limited, the technical terms“mounting”,“connection”,“connection”,“fixing” and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the application can be understood according to the specific circumstances.

[0039] In the description of the embodiments of this application, unless otherwise expressly specified and limited, when an element is referred to as "fixed to" or "set on" another element, it may be directly on or indirectly on the other element. When an element is referred to as "connected to" another element, it may be directly connected to or indirectly connected to the other element.

[0040] like Figures 1-2 As shown, in one embodiment of this application, an ultrasonic compression molding apparatus 100 is provided, which is suitable for preparing polymer surface microstructures 200.

[0041] The ultrasonic compression molding apparatus 100 of this application will be described below with reference to some embodiments.

[0042] The ultrasonic compression molding apparatus 100 includes an ultrasonic mechanism 110 and a mold mechanism 120.

[0043] The ultrasonic mechanism 110 includes a drive member 111 and an ultrasonic punch 112. The drive member 111 is connected to the ultrasonic punch 112 to drive the ultrasonic punch 112 to vibrate ultrasonically. It is understood that the drive member 111 can drive the ultrasonic punch 112 to vibrate ultrasonically. In one embodiment, the drive member 111 includes an ultrasonic generator 1111 and an ultrasonic transducer 1112. The ultrasonic transducer 1112 is connected between the ultrasonic generator 1111 and the ultrasonic punch 112, converting the electrical power generated by the ultrasonic generator 1111 into ultrasonic kinetic energy, thereby driving the ultrasonic punch 112 to vibrate ultrasonically. Of course, in other embodiments, the drive member 111 can also be other components capable of driving the ultrasonic punch 112 to vibrate ultrasonically.

[0044] The mold mechanism 120 includes a top mold 121 and a template assembly 122. The ultrasonic punch 112 and the template assembly 122 are located on opposite sides of the top mold 121. The template assembly 122 is provided with a template cavity 1223. It can be understood that the ultrasonic punch 112 is located on one side of the top mold 121, and the template assembly 122 is located on the side of the top mold 121 opposite to the ultrasonic punch 112. For example, the ultrasonic punch 112 is located on the upper side of the top mold 121, and the template assembly 122 is located on the lower side of the top mold 121. The template assembly 122 has a template cavity 1223, so that after the polymer melt flows into the template cavity 1223 and cools and solidifies, a polymer surface microstructure 200 can be obtained. In some embodiments, the cavity wall of the template cavity 1223 can be provided with protrusions or depressions, and powder particles 130 can be placed in the template cavity 1223 to prepare polymer surface microstructures 200 with complex shapes. The specific design depends on the actual shape of the microstructure and is not limited here.

[0045] The top die 121 is provided with a stamping hole 1211 for accommodating the ultrasonic punch 112 and a communication hole 1212 for communicating the stamping hole 1211 and the die cavity 1223, and the communication hole 1212 is located between the stamping hole 1211 and the die cavity 1223; it can be understood that the stamping hole 1211 is used to accommodate the ultrasonic punch 112, the communication hole 1212 is used to communicate the stamping hole 1211 and the die cavity 1223, and the communication hole 1212 is located between the stamping hole 1211 and the die assembly 122, so that the polymer melt in the stamping hole 1211 can flow into the die cavity 1223 through the communication hole 1212.

[0046] The aperture D1 of the stamping hole 1211 is larger than the aperture D2 of the communication hole 1212, so that a stepped surface 1213 is formed between the stamping hole 1211 and the communication hole 1212, and the stepped surface 1213 is provided with a raw material groove 1214 for accommodating the polymer master batch 300; it can be understood that the aperture D1 of the stamping hole 1211 is larger than the aperture D2 of the communication hole 1212, so that the stamping hole 1211 and the communication hole 1212 form a stepped hole structure, the surface located between the stamping hole 1211 and the communication hole 1212 and located on the side of the communication hole 1212 forms the stepped surface 1213, the stepped surface 1213 is recessed towards the die assembly 122 to form the raw material groove 1214, and the raw material groove 1214 is used to accommodate the polymer master batch 300.

[0047] The polymer master batch 300 can be a granular material of thermoplastic polymer, and the material of the polymer master batch 300 can be but is not limited to polyvinyl chloride, polyethylene, and polypropylene.

[0048] The ultrasonic plastic compression molding device 100 of the embodiment of the application is used, the polymer master batch 300 is first placed in the raw material groove 1214; then, the driving member 111 is started, the driving member 111 drives the ultrasonic punch 112 to ultrasonically vibrate in the stamping hole 1211 and press on the polymer master batch 300, so that the polymer master batch 300 is plasticized and melted to form a polymer melt; and under the ultrasonic vibration and pressing of the ultrasonic punch 112, the polymer melt flows to the communication hole 1212, and then flows into the die cavity 1223 through the flow hole 12231; after the polymer melt flows into the die cavity 1223 to a predetermined state; the ultrasonic vibration of the ultrasonic punch 112 is turned off; finally, after the polymer melt is cooled and formed, the polymer surface microstructure 200 is formed, and finally the polymer surface microstructure 200 is taken out, that is, the preparation of the polymer surface microstructure 200 is completed.

[0049] In the preparation process of the polymer microstructure, the polymer master batch 300 is melted in the raw material groove 1214, so as to avoid the severe friction between the polymer master batch 300 and the template cavity 1223, reduce the damage of the template assembly 122, facilitate the repeated use of the template assembly 122, and the template assembly 122 can also use a material with lower strength and hardness, thereby reducing the manufacturing cost of the ultrasonic plastic compression molding device 100; the ultrasonic punch 112 and the template assembly 122 are located on opposite sides of the top die 121, so that the polymer melt can also be subjected to the ultrasonic vibration of the ultrasonic punch 112, thereby reducing the viscosity of the polymer melt, and the template cavity 1223 of the template 1222 can also have a certain surface temperature, improving the flowability and filling capacity of the polymer melt, so that the polymer melt can flow into the microstructure with smaller size and deeper depth in the template cavity 1223, further improving the molding quality of the polymer surface microstructure 200; at the same time, under the continuous action of ultrasonic vibration, it is beneficial to remove the air remaining in the polymer melt and reduce the formation of air bubbles, further improving the molding quality of the polymer surface microstructure 200; the ultrasonic plastic compression molding device 100 has simple structure, low manufacturing cost and good molding quality, and is beneficial to realize large-scale, low-cost and high-quality preparation of polymer surface microstructures 200 with multiple levels and high aspect ratio.

[0050] It should be noted that the ultrasonic vibration of the ultrasonic punch 112 is mainly axial vibration along the stamping hole 1211 to press the polymer master batch 300 to melt; the stamping hole 1211 and the ultrasonic punch 112 are matched in shape, and the hole diameter D1 of the stamping hole 1211 is slightly larger than the outer diameter D3 of the ultrasonic punch 112, so that the ultrasonic punch 112 can ultrasonically vibrate along the axis of the stamping hole 1211 (see the direction indicated by the arrow A in Figure 1 The shapes of the stamping hole 1211 and the communication hole 1212 can be various, such as circular, elliptical, etc., and the specific shape is determined according to the shape of the polymer and the shape of the ultrasonic punch 112, which is not limited here.

[0051] In the preparation process of the polymer surface microstructure 200, the polymer melt flows into the template cavity 1223 to a predetermined state, which can mean that the polymer melt completely fills the template cavity 1223, or that there is a certain distance between the polymer melt in the template cavity 1223 and the communication hole 1212. Among them, in the case that the polymer melt completely fills the template cavity 1223, the template cavity 1223 can have polymer melt, while the communication hole 1212 does not have polymer melt; the template cavity 1223 can have polymer melt, and the communication hole 1212 has polymer melt; the template cavity 1223 can have polymer melt, and the communication hole 1212, the stamping hole 1211 and the raw material groove 1214 all have polymer melt; wherein the polymer material in the communication hole 1212, the stamping hole 1211 and the raw material groove 1214 is fixed to form the base of the polymer surface microstructure 200 after the polymer melt is cooled and formed; wherein the depth of the communication hole 1212 can be changed to adjust the height of the base to meet different use requirements.

[0052] In another embodiment of the present application, in combination with Figure 2 As shown in the figure, the raw material groove 1214 is annularly arranged on the outer peripheral side of the communication hole 1212.

[0053] It can be understood that the raw material groove 1214 is an annular structure, which is annularly arranged on the outer peripheral side of the communication hole 1212.

[0054] By adopting the technical scheme of this embodiment, the raw material groove 1214 is annularly arranged on the outer peripheral side of the communication hole 1212, so that when the polymer master batch 300 is uniformly placed in the raw material groove 1214, the polymer master batch 300 can be uniformly distributed on the outer peripheral side of the communication hole 1212, and after the polymer master batch 300 is melted, the polymer melt can flow into the template cavity 1223 uniformly from the four sides of the communication hole 1212, which is beneficial to reduce the filling dead angle of the template cavity 1223 and improve the forming quality of the polymer surface microstructure 200.

[0055] In one embodiment, the stamping hole 1211 and the communication hole 1212 are coaxially arranged, so that the stepped surface 1213 is annularly arranged on the communication hole 1212, thereby facilitating the processing and manufacturing of the raw material groove 1214 annularly arranged on the outer peripheral side of the communication hole 1212, and in addition, the overall structure is regular, which is also beneficial to processing and manufacturing.

[0056] In another embodiment of the present application, in combination with Figure 1 As shown in the figure, the depth of the raw material groove 1214 is 0.1mm-0.5mm.

[0057] By adopting the technical solution of this embodiment, the depth range of the raw material tank 1214 is set between 0.1mm and 0.5mm. The depth H of the raw material tank 1214 is set reasonably, so that the polymer masterbatch 300 can be stably located in the raw material tank 1214 and melted by the ultrasonic vibration of the ultrasonic punch 112. This also helps to improve the utilization rate of the polymer masterbatch 300 and reduce the manufacturing cost. It also avoids the polymer masterbatch 300 from moving into the template cavity 1223 before melting due to the depth H of the raw material tank 1214 being too small, and it also avoids the polymer melt from accumulating too much in the raw material tank 1214 and causing material waste due to the depth H of the raw material tank 1214 being too large.

[0058] In one embodiment, the depth H of the raw material tank 1214 may be, but is not limited to, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, or 0.5mm.

[0059] In one embodiment, the hole depth of the punch hole 1211 is about 3 mm, and the groove depth H of the raw material groove 1214 is about 0.3 mm. With this setting, the size of the mold mechanism 120 is reasonable, which is beneficial for processing the polymer surface microstructure 200.

[0060] In another embodiment of this application, combined with Figure 1 As shown, the projection of the ultrasonic punch 112 onto the plane perpendicular to the axis of the punching hole 1211 covers the projection of the template cavity 1223 onto the plane perpendicular to the axis of the punching hole 1211.

[0061] By adopting the technical solution of this embodiment, the polymer melt in the template cavity 1223 is located within the coverage range of the ultrasonic vibration of the ultrasonic punch 112 in the axial direction of the punching hole 1211. Under the direct pressure of the ultrasonic punch 112, the polymer melt can better fill the small and deep microstructures in the template cavity 1223, further improving the molding quality of the polymer surface microstructure 200. In addition, the role of ultrasonic vibration is fully utilized to better reduce the viscosity of the polymer melt, while making the microporous structure of the template 1222 have a better surface temperature, better improving the melt flowability and filling capacity, effectively improving the molding quality of the polymer surface microstructure 200, and making it more conducive to the preparation of multi-level and high aspect ratio polymer surface microstructures 200.

[0062] In another embodiment of this application, combined with Figure 1As shown in the figure, the template assembly 122 comprises a bottom die 1221 and at least one template 1222, each template 1222 is located between the top die 121 and the bottom die 1221, each template 1222 is provided with a through hole 12231, and the through holes 12231 of each template 1222 jointly form a template cavity 1223; the through hole 12231 of the template 1222 adjacent to the top die 121 is communicated with the communication hole 1212, and the bottom die 1221 is used for sealing the through hole 12231 of the template 1222 adjacent to the bottom die 1221.

[0063] It can be understood that, in the case that the number of templates 1222 is one, the template 1222 is located between the bottom die 1221 and the top die 121, the through hole 12231 provided on the template 1222 forms the template cavity 1223, the bottom plate seals the top opening of the through hole 12231, and the top opening of the through hole 12231 is communicated with the communication hole 1212; in the case that the number of templates 1222 is multiple, multiple templates 1222 are located between the bottom die 1221 and the top die 121, the through holes 12231 of the multiple templates 1222 are communicated with each other and form the template cavity 1223, and the bottom die 1221 seals the through hole 12231 of the template 1222 adjacent to the bottom plate, and the through hole 12231 of the template 1222 adjacent to the top die 121 is communicated with the communication hole 1212, so that the polymer melt flowing out of the communication hole 1212 can flow into the through hole 12231 to form, thereby obtaining the polymer surface microstructure 200. As an example, the bottom die 1221 can be a flat plate. The shape of the through hole 12231 can be various, for example: circular, square, oval, etc.; the shape of the through hole 12231 of the primary template 12221, the shape of the through hole 12231 of the secondary template 12222 and the shape of the through hole 12231 of the tertiary template 12223 can be the same or different.

[0064] By adopting the technical scheme of the embodiment, different polymer surface microstructures 200 can be obtained by changing the order of the templates 1222 or replacing different templates 1222, which is beneficial to improve the application range of the ultrasonic plastic compression molding device 100, and the through hole 12231 on the template 1222 is used to form the template cavity 1223, which has a simple structure and is simple and convenient to manufacture.

[0065] In an embodiment, the number of templates 1222 can be one, two or more than three, so that single-stage, two-stage and more than three-stage polymer surface microstructures 200 can be prepared respectively.

[0066] In another embodiment of the present application, in combination with Figure 1 and Figure 2 As shown in the figure, the number of templates 1222 is multiple, and the top die 121, the multiple templates 1222 and the bottom die 1221 are sequentially and closely connected.

[0067] It is understood that multiple templates 1222 are located between the top mold 121 and the bottom mold 1221, and the multiple templates 1222 are along the first direction (see...). Figure 1 The templates 1221 and 1222 are sequentially connected in the direction indicated by the middle arrow A. The first direction is the distribution direction of the top mold 121 and the bottom mold 1221. The template 1222 adjacent to the top mold 121 is connected to the top mold 121 in close contact, and the template 1222 adjacent to the bottom mold 1221 is connected to the bottom mold 1221 in close contact. For example, fasteners can be used to sequentially pass through the top mold 121, multiple templates 1222, and the bottom mold 1221, thereby locking the top mold 121, multiple templates 1222, and the bottom mold 1221 together in close contact. The fasteners can be bolts, screws, etc. The polymer melt can also gradually fill the through holes 12231 from the connecting holes 1212 along the first direction, thereby forming a multi-level polymer surface microstructure 200.

[0068] By adopting the technical solution of this embodiment, the top mold 121, multiple templates 1222 and bottom mold 1221 are assembled in close contact along the first direction to prevent the polymer melt from overflowing between adjacent parts.

[0069] In one embodiment, the template 1222 may be provided with one or more through holes 12231. For example, the template 1222 may be provided with two, three, four or more through holes 12231. The specific through holes 12231 may be set according to the shape of the polymer and is not limited here.

[0070] In one embodiment, in a first direction, one through hole 12231 of the preceding template 1222 is in relative communication with multiple through holes 12231 of the following template 1222. The specific configuration can be determined according to the shape of the polymer and is not limited here. As an example, one through hole 12231 of the preceding template 1222 is in relative communication with four through holes 12231 of the following template 1222.

[0071] In the embodiment, the number of the templates 1222 is three, and the three templates 1222 are sequentially divided into a first-level template 12221, a second-level template 12222, and a third-level template 12223 along the first direction; the first-level template 12221 is distributed with micrometer-scale through holes 12231; the through holes 12231 of the second-level template 12222 have a hole diameter much smaller than that of the through holes 12231 of the first-level template 12221; the third-level template 12223 is provided with larger through holes 12231, and the through holes 12231 of the third-level template 12223 are loaded with compacted powder particles 130, and the size of the powder particles 130 is much smaller than the hole diameter of the through holes 12231 of the second-level template 12222, so that after the polymer melt is filled between the through holes 12231 of the first-level template 12221, the through holes 12231 of the second-level template 12222, and the powder particles 130 of the third-level template 12223, a nanometer-scale multi-level polymer surface microstructure 200 with a high aspect ratio can be prepared with high quality.

[0072] In the embodiment, the first-level template 12221 is provided with nine through holes 12231, one of which is coaxially arranged with the communication hole 1212, and the other eight through holes 12231 are uniformly distributed on the side of the through hole 12231; and each through hole 12231 is oppositely and communicatively arranged with four arrayed through holes 12231 of the second-level template 12222. The through holes 12231 of the first-level template 12221 are circular holes, and the through holes 12231 of the second-level template 12222 are circular holes.

[0073] In another embodiment of the present application, in combination with Figure 3 As shown in FIG. 8, a forming method for preparing a polymer surface microstructure 200 is provided, which uses the ultrasonic plastic pressing forming device 100 of the above-mentioned embodiments, and includes the following steps:

[0074] Charging: placing the polymer master batch 300 in the raw material groove 1214;

[0075] Starting ultrasonic vibration: inserting the ultrasonic punch 112 into the pressing hole 1211, and then starting the driving member 111 to drive the ultrasonic punch 112 to ultrasonically vibrate and press the polymer master batch 300, so that the polymer master batch 300 is plasticized and melted to form a polymer melt; and under the ultrasonic vibration and pressing of the ultrasonic punch 112, the polymer melt flows into the template cavity 1223 through the communication hole 1212;

[0076] Stopping ultrasonic vibration: after the template cavity 1223 is filled to a preset state, the ultrasonic vibration of the ultrasonic punch 112 is stopped.

[0077] Demolding: after the polymer melt is cooled and formed into the polymer surface microstructure 200, the polymer surface microstructure 200 is taken out.

[0078] The forming method for preparing the polymer surface microstructure 200 of the embodiment of the application first places the polymer master batch 300 into the raw material groove 1214; then, the driving member 111 is started, the ultrasonic punch 112 is driven to ultrasonically vibrate in the stamping hole 1211 and press on the polymer master batch 300, so that the polymer master batch 300 is plasticized and melted to form a polymer melt; and under the ultrasonic vibration and pressing of the ultrasonic punch 112, the polymer melt flows towards the communication hole 1212, and then flows into the template cavity 1223 through the flow hole 12231; the polymer melt is allowed to flow into the template cavity 1223 to a predetermined state; the ultrasonic vibration of the ultrasonic punch 112 is turned off; finally, the polymer melt is cooled and formed to form the polymer surface microstructure 200, and finally the polymer surface microstructure 200 is taken out, and the preparation of the polymer surface microstructure 200 is completed.

[0079] The forming method for preparing the polymer surface microstructure 200 of the embodiment of the application is simple in operation, is conducive to large-scale production, and the ultrasonic plastic pressing forming device 100 is simple in structure, low in cost and good in forming quality of the polymer microstructure, and is conducive to realizing large-scale, low-cost and high-quality preparation of the polymer surface microstructure 200 with multiple levels and high aspect ratio.

[0080] In another embodiment of the application, the ultrasonic plastic pressing forming device 100 is combined with the ultrasonic vibration and pressing device 110. Figure 2 As shown in the figure, the raw material groove 1214 is arranged on the outer periphery side of the communication hole 1212; in the loading step, the polymer master batch 300 is uniformly loaded in the raw material groove 1214, so that the polymer master batch 300 is uniformly arranged on the outer periphery side of the communication hole 1212.

[0081] By adopting the technical scheme of the embodiment, the polymer master batch 300 can be uniformly distributed on the outer periphery side of the communication hole 1212, and after the polymer master batch 300 is melted, the polymer melt can be uniformly flowed into the template cavity 1223 from the four sides of the communication hole 1212, which is conducive to reducing the filling dead angle of the template cavity 1223 and improving the forming quality of the polymer surface microstructure 200.

[0082] In another embodiment of the application, in the step of turning off the ultrasonic vibration, after the ultrasonic vibration of the ultrasonic punch 112 is turned off, the ultrasonic punch 112 is pressed against the polymer melt and gives the polymer melt a preset pressure.

[0083] The preset pressure can be set according to actual needs, which is not limited herein.

[0084] By adopting the technical scheme of the embodiment, after the ultrasonic punch 112 stops ultrasonic vibration, the ultrasonic punch 112 gives the polymer melt a certain pressure, so that the polymer melt is in a pressure-keeping state, and the polymer melt can also enter the microstructure with a smaller size and a deeper depth in the template cavity 1223, which is beneficial to the preparation of a polymer surface microstructure 200 with more levels and a high aspect ratio.

[0085] In another embodiment of the present application, the vibration frequency of the ultrasonic punch 112 is greater than 20 kHz.

[0086] By adopting the technical scheme of the embodiment, the vibration frequency of the ultrasonic punch 112 is greater than 20 kHz, which is beneficial to the rapid melting of the polymer master batch 300 and improves the production efficiency; and is also beneficial to improving the flowability and filling capacity of the polymer melt, which is beneficial to the preparation of a polymer surface microstructure 200 with more levels and a high aspect ratio.

[0087] In one embodiment, the polymer master batch 300 is arranged around the communication hole 1212 and is uniformly distributed, and the polymer master batch 300 and the template assembly 122 are arranged opposite to the acting surface of the ultrasonic punch 112, so that the ultrasonic plastic compression molding device 100 has the advantages of ultrasonic embossing and ultrasonic plasticization micro injection molding while avoiding or improving the defects existing in them. Compared with ultrasonic embossing, the violent friction between the polymer master batch 300 and the cavity wall of the template cavity 1223 is avoided, the damage of the template assembly 122 is reduced, the reuse of the template 1222 is facilitated, the material selection range of the template 1222 is expanded, and the manufacturing cost is reduced. Compared with ultrasonic plasticization micro injection molding, the polymer melt is always in the main ultrasonic vibration coverage range and is directly pressed by the ultrasonic punch 112, so that the polymer melt fills the mold cavity sufficiently, the effect of ultrasonic vibration is fully played, the viscosity of the polymer melt is reduced, the mold cavity has a certain surface temperature, the flowability and filling capacity of the melt are improved, and the continuous effect of ultrasonic vibration is beneficial to the removal of residual air in the polymer melt and the reduction of the formation of air bubbles, thereby improving the molding quality of the polymer microstructure. Therefore, the ultrasonic plastic compression molding device 100 and the molding method for preparing the polymer surface microstructure 200 provided in the embodiment of the present application can realize the filling and molding of the polymer melt in the multi-level template 1222, and can be used to prepare a polymer surface microstructure 200 with high quality, multiple levels, nanoscale and a high aspect ratio.

[0088] In one embodiment, the polymer melt can be cooled and molded in a room temperature environment and under the pressure keeping of the ultrasonic punch 112, which is beneficial to reducing the manufacturing cost; of course, the polymer melt can also be cooled in an environment lower than room temperature, which is selected according to actual needs.

[0089] In one embodiment, in the demolding step, the template assembly 122 and the polymer surface microstructure 200 thereon can be removed to realize demolding.

[0090] In one embodiment, the ultrasonic mechanism 110 can be an automatic ultrasonic mechanism 110, and in the loading step, the process parameters such as the resonance frequency, the ultrasonic amplitude, the ultrasonic action pressure, the ultrasonic action time, and the pressure maintaining time can be set according to the production requirements.

[0091] The present application will be described below in combination with some embodiments.

[0092] Embodiment One

[0093] In this embodiment, in combination with Figures 1-2 As shown in FIG. 12B, the number of the templates 1222 is three, and the three templates 1222 are sequentially divided into a first-level template 12221, a second-level template 12222, and a third-level template 12223 along the first direction; the first-level template 12221 is distributed with micrometer-scale through holes 12231; the through holes 12231 of the second-level template 12222 have a hole diameter much smaller than that of the through holes 12231 of the first-level template 12221; the third-level template 12223 is provided with larger through holes 12231, and the third-level template 12223 is loaded with compacted powder particles 130 in the through holes 12231, and the size of the powder particles 130 is much smaller than the hole diameter of the through holes 12231 of the second-level template 12222, so that after the polymer melt is filled between the through holes 12231 of the first-level template 12221, the through holes 12231 of the second-level template 12222, and the powder particles 130 of the third-level template 12223, a nanometer-scale multi-level polymer surface microstructure 200 with a high aspect ratio can be prepared with high quality.

[0094] In this embodiment, the first-level template 12221 is provided with a plurality of through holes 12231, and the through holes 12231 of the first-level template 12221 are arranged in an array; the second-level template 12222 is provided with a plurality of through holes 12231, and the through holes 12231 of the second-level template 12222 are arranged in an array; the through holes 12231 of the first-level template 12221 are circular holes, and the through holes 12231 of the second-level template 12222 are circular holes.

[0095] Embodiment Two

[0096] The difference between this embodiment and Embodiment One is that, in combination with Figure 3 As shown in FIG. 12B, the number of the templates 1222 is three, and the three templates 1222 are sequentially divided into a first-level template 12221, a second-level template 12222, and a third-level template 12223 along the first direction; the first-level template 12221 is distributed with micrometer-scale through holes 12231; the second-level template 12222 is provided with a plurality of through holes 12231, and the through holes 12231 of the second-level template 12222 are arranged in an array; the through holes 12231 of the first-level template 12221 are circular holes, and the through holes 12231 of the second-level template 12222 are circular holes.

[0097] In this embodiment, the aperture of the through hole 12231 of the primary template 12221 is 50 pm, the center distance between the through hole 12231 on the outer side and the through hole 12231 on the inner side is 100 pm, and the thickness of the primary template 12221 is 0.2 mm of 304 stainless steel template. The polymer master granule 300 is selected as a polypropylene master granule, and the particle size is about 3*2.5*5 mm. 3 .

[0098] In this embodiment, 8 polypropylene master granules are uniformly distributed in the raw material tank 1214, and the resonance frequency, ultrasonic amplitude, ultrasonic action pressure, ultrasonic action time and pressure holding time are set to 20 kHz, 60 pm, 300 kPa, 0.3 s and 8 s respectively. Start ultrasonic vibration, the ultrasonic transducer 1112 converts the electric power generated by the ultrasonic wave generator into ultrasonic vibration of the ultrasonic punch 112 and extrudes the polypropylene master granule, so that the polypropylene master granule is plasticized and melted; under the vibration and pressing of the ultrasonic punch 112, the polypropylene melt flows to the through hole 12231 of the primary template 12221 and fills the through hole 12231 of the primary template 12221; stop ultrasonic action, and the polypropylene melt is cooled and formed under the pressure holding of the ultrasonic punch 112 in the room temperature environment. The demolding takes out the polypropylene surface single-stage array structure with a height of 0.2 mm, a diameter of about 50 pm and a pitch of 100 pm.

[0099] Example Three

[0100] The difference between this embodiment and example two is that a secondary template 12222 is added, that is, the number of templates 1222 is two, and the two templates 1222 are respectively a primary template 12221 and a secondary template 12222. Figure 4 As shown in the figure, a secondary template 12222 is added, that is, the number of templates 1222 is two, and the two templates 1222 are respectively a primary template 12221 and a secondary template 12222.

[0101] In this embodiment, the secondary template 12222 is an anodic aluminum oxide (AAO) template, the aperture of the through hole 12231 of the secondary template 12222 is 250 nm, the center distance between the two adjacent through holes 12231 of the secondary template 12222 is 450 nm, and the thickness of the secondary template 12222 is 50 pm.

[0102] In this embodiment, the same polypropylene master granule quantity and process parameters as in example two are used. After cooling and forming, the polypropylene workpiece is demolded, and then soaked in a 20%wt sodium hydroxide solution for about 10 min, and the secondary template 12222 embedded on the surface of the polypropylene workpiece is dissolved and removed, to obtain a secondary polypropylene surface microstructure with a nanowire array distributed on the upper end face of the microcylinder array.

[0103] Example Four

[0104] The difference between this embodiment and embodiment two is that the combination of the powder particles 130 in the tertiary template 12223 is changed. Figure 5 As shown in FIG. 2, one tertiary template 12223 is added, i.e., the number of templates 1222 is two, and the two templates 1222 are the primary template 12221 and the tertiary template 12223, respectively.

[0105] In this embodiment, the powder particles 130 in the tertiary template 12223 are BaTiO3 powder particles 130 with an average particle size of about 40 nm. The ultrasonic action time is set to 0.28 s, and other process parameters and the number of polypropylene master batches are the same as those in embodiment two. After cooling and forming, the polypropylene workpiece is removed, and then it is soaked in 3 mol of hydrochloric acid for about 2 hours to dissolve and remove the BaTiO3 powder particles 130 embedded in the polypropylene workpiece, thereby obtaining a secondary polypropylene surface microstructure with a mixed micro-hole and nano-hole on the upper end surface of the micro-cylinder array.

[0106] Embodiment five

[0107] The difference between this embodiment and embodiment one is that the combination of the powder particles 130 in the tertiary template 12223 is changed. Figure 6 As shown in FIG. 2, the through hole 12231 of the primary template 12221 is a square hole with a size of 1*1 mm 2 , and the center distance between the square hole on the outside and the square hole on the inside is 1.2 mm. The primary template 12221 is a 304 stainless steel template with a thickness of 0.3 mm. The pore size of the through hole 12231 of the secondary template 12222 is 100 μm. The center distance between adjacent two through holes 12231 is 150 μm. The secondary template 12222 is a 304 stainless steel template with a thickness of 0.2 mm. The powder particles 130 in the tertiary template 12223 are BaTiO3 powder particles with an average particle size of about 40 nm.

[0108] In this embodiment, the number of polypropylene master batches is 12, the ultrasonic action time is 0.35 s, and other process parameters are the same as those in embodiment two. After cooling and forming, the polypropylene workpiece is removed, and then it is soaked in 3 mol of hydrochloric acid for about 2 hours to dissolve and remove the BaTiO3 powder particles 130 embedded in the polypropylene workpiece, thereby obtaining a tertiary polypropylene surface microstructure with a combination of millimeter, micron and nanometer scales.

[0109] The above description of each embodiment tends to emphasize the differences between each embodiment, and the same or similar parts can be referred to each other. For the sake of brevity, the same or similar parts will not be described herein.

[0110] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some or all of the technical features can be replaced equivalently. Such modifications or replacements do not change the essence of the corresponding technical solutions, which should be covered in the scope of the claims and the specification of the present application. In particular, the technical features mentioned in each embodiment can be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An ultrasonic compression molding apparatus, suitable for preparing polymer surface microstructures, characterized in that, The ultrasonic compression molding device includes: An ultrasonic mechanism includes a drive unit and an ultrasonic punch, the drive unit being connected to the ultrasonic punch to drive the ultrasonic punch to ultrasonic vibration; and A mold mechanism includes a top mold and a template assembly, wherein the ultrasonic punch and the template assembly are located on opposite sides of the top mold, and the template assembly is provided with a template cavity; The top mold is provided with a punching hole for accommodating the ultrasonic punch and a connecting hole for connecting the punching hole and the template cavity, the connecting hole being located between the punching hole and the template cavity; Wherein, the diameter of the punching hole is larger than the diameter of the connecting hole, so that a stepped surface is formed between the punching hole and the connecting hole, and the stepped surface is provided with a raw material groove for accommodating polymer masterbatch; The raw material trough is arranged on the outer periphery of the connecting hole; The depth of the raw material tank ranges from 0.1mm to 0.5mm; The projection of the ultrasonic punch on a plane perpendicular to the axis of the punching hole overlaps the projection of the template cavity on a plane perpendicular to the axis of the punching hole.

2. The ultrasonic compression molding apparatus according to claim 1, characterized in that: The template assembly includes a bottom mold and at least one template, each template being located between the top mold and the bottom mold. Each template has a through hole, and the through holes of each template together form the template cavity. The through hole of the template adjacent to the top mold is connected to the connecting hole, and the bottom mold is used to seal the through hole of the template adjacent to the bottom mold.

3. The ultrasonic compression molding apparatus according to claim 2, characterized in that: The number of templates is multiple, and the top mold, multiple templates and bottom mold are connected in close sequence.

4. A molding method for preparing polymer surface microstructures, characterized in that, Using the ultrasonic compression molding apparatus according to any one of claims 1 to 3, the molding method for preparing polymer surface microstructures includes the following steps: Loading: Place the polymer masterbatch into the raw material tank; Initiating ultrasonic vibration: Insert the ultrasonic punch into the punching hole, then activate the drive to drive the ultrasonic punch to vibrate ultrasonically and squeeze the polymer masterbatch, so that the polymer masterbatch is plasticized and melted to form a polymer melt; and, under the ultrasonic vibration and pressing of the ultrasonic punch, the polymer melt flows into the template cavity through the connecting hole. Turn off ultrasonic vibration: After the template cavity is filled to the preset state, turn off the ultrasonic vibration of the ultrasonic punch; Demolding: After the polymer melt cools and solidifies to form polymer surface microstructures, the polymer surface microstructures are removed.

5. The molding method for preparing polymer surface microstructures according to claim 4, characterized in that: In the loading step, the raw material tank is arranged around the outer periphery of the connecting hole, and the polymer masterbatch is uniformly loaded into the raw material tank so that the polymer masterbatch is uniformly surrounding the outer periphery of the connecting hole.

6. The molding method for preparing polymer surface microstructures according to claim 4 or 5, characterized in that: In the step of shutting off ultrasonic vibration, after shutting off the ultrasonic vibration of the ultrasonic punch, the ultrasonic punch presses against the polymer melt and applies a preset pressure to the polymer melt.

7. The molding method for preparing polymer surface microstructures according to claim 4 or 5, characterized in that: The vibration frequency of the ultrasonic punch is greater than 20kHz.

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