阅读说明：本技术 一种高温作用下制备pmma内部微通道的方法 (Method for preparing PMMA (polymethyl methacrylate) internal micro-channel under high-temperature action ) 是由 张俐楠 陆凯 黄阿龙 刘红英 吴立群 王洪成 于 2021-06-16 设计创作，主要内容包括：本发明公开了一种高温作用下制备PMMA内部微通道的方法,其按如下步骤进行：步骤一：确定阵列微孔的基本参数,后采用纳米微针在PMMA表面打出微孔；步骤二：将打好微孔的常态下PMMA放置于高温环境中,在高温下将PMMA加热到熔融态,高温加热的温度为150-200℃；熔融态的PMMA在表面能的驱动下向着能量最小的方向运动,表面微孔愈合,形成内部微通道。本发明从能量角度出发,实现制备性能完善的聚合物PMMA内部微通道结构,为聚合物内部微通道的制备提供新的方案。(The invention discloses a method for preparing a PMMA internal micro-channel under the action of high temperature, which comprises the following steps: the method comprises the following steps: determining basic parameters of the array micropores, and then punching the micropores on the PMMA surface by adopting nano microneedles; step two: placing PMMA with perforated micropores in a high-temperature environment in a normal state, and heating the PMMA to a molten state at a high temperature of 150-; the molten PMMA moves towards the direction with the minimum energy under the driving of the surface energy, and the surface micropores are healed to form the internal microchannels. The invention realizes the preparation of the internal micro-channel structure of the polymer PMMA with perfect performance from the energy perspective, and provides a new scheme for the preparation of the internal micro-channel of the polymer.)

1. A method for preparing PMMA internal micro-channel under the action of high temperature is characterized by comprising the following steps:

the method comprises the following steps: determining basic parameters of the array micropores, and then punching the micropores on the PMMA surface by adopting nano microneedles;

step two: placing PMMA with punched micropores in a high-temperature environment in a normal state, and heating the PMMA to a molten state at a high temperature of 150-200 ℃; the molten PMMA moves towards the direction with the minimum energy under the driving of the surface energy, and the surface micropores are healed to form the internal microchannels.

2. The process for preparing PMMA internal micro-channels under the action of high temperature according to claim 1, wherein,

in the first step, the depth H of the cylindrical holes of the micro-holes of the array, the diameter D of the holes and the distance Ds between the holes are determined according to the requirement of forming the PMMA micro-channels.

3. The process for preparing PMMA internal micro-channels under the action of high temperature according to claim 2,

the size of the cylindrical holes is kept consistent and is uniformly distributed on the PMMA surface.

4. The process for preparing PMMA internal micro-channels under the action of high temperature according to claim 1, wherein,

in the first step, nanometer micro-needles are adopted to punch regularly arranged micro-holes with high depth-to-width ratio on the surface of PMMA.

5. The process for preparing PMMA internal micro-channels under the action of high temperature according to claim 1, wherein,

in the first step, nanometer micro-needles are adopted to punch micropores which are irregularly arranged on the surface of PMMA.

6. Process for the preparation of PMMA internal micro-channels at elevated temperature according to any of the claims 1 to 5,

the PMMA is cuboid.

7. Process for the preparation of PMMA internal micro-channels at elevated temperature according to any of the claims 1 to 5,

the cross-section of the microchannel is circular or elliptical.

Technical Field

The invention belongs to the technical field of micro-nano manufacturing, and particularly relates to a method for preparing a micro-channel in a PMMA polymer under the action of high temperature.

Background

At present, the processing technology of the internal microstructure of the polymer is increasingly researched, the application of the internal microchannel of the polymer is quite extensive, and the most important application is that the microfluidic chip is internally provided with the microchannel with tiny and complex size. At present, PMMA is used as a material for preparing the microfluidic chip. The method for manufacturing the polymer internal microchannel of the microfluidic chip is many, and the most widely used method is the hot press molding method, and in addition, some methods such as injection molding, laser ablation and the like are available. At present, the mature hot press molding method is not formed on a piece of polymer base material, but two parts of polymers of a substrate and a template are firstly made, then two PMMA plates are connected by using a bonding mode to finally form an internal micro-channel, and the preparation of the final micro-fluidic chip is realized. The bonding method for the polymer mainly comprises thermal bonding, ultrasonic bonding, laser bonding, adhesive bonding and the like, wherein the most widely applied method is thermal bonding, and the microfluidic chip can be obtained by aligning a substrate and a cover plate, heating and pressurizing for a period of time, and cooling. The method is simple to operate, only pressure and temperature need to be adjusted during bonding, but the temperature of the polymer needs to be kept near the glass transition temperature, although bonding is easier as the temperature is higher, the high temperature is likely to deform the polymer microchannel, and the low temperature is likely to cause the result of insufficient bonding strength.

Disclosure of Invention

Aiming at the problems in the prior art, the invention explores the forming rule of the PMMA in a molten state driven by the surface energy from the perspective of energy, so as to prepare an internal micro-channel on a PMMA material, and provides a method for preparing the internal micro-channel of the PMMA polymer under the action of high temperature.

The invention grasps the forming rule of PMMA from the energy point of view, when the polymer enters the melting state, the polymer can move under the action of the surface energy, and finally a stable internal micro-channel is formed, thereby preparing the internal micro-channel structure of the polymer PMMA.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method for preparing PMMA internal micro-channels under the action of high temperature comprises the following steps:

the method comprises the following steps: determining basic parameters of the array micropores, and then punching the micropores on the surface of the polymer PMMA by adopting nano microneedles.

Step two: placing the polymer PMMA with the micropores in a high-temperature environment in a normal state, and heating the PMMA to a molten state under high-temperature heating at the temperature of 150-200 ℃. The molten polymer PMMA moves towards the direction with the minimum energy under the driving of the surface energy, and the surface micropores are healed to form the internal microchannels.

Preferably, in step one, the depth H of the cylindrical holes of the micro-holes of the array, the diameter D of the holes and the distance Ds between the holes are determined according to the requirements of forming PMMA micro-channels.

Preferably, the size of the cylindrical holes is kept uniform and evenly distributed over the PMMA surface.

Preferably, in the step one, nano-micro-needles are used to punch regularly arranged micro-pores with high aspect ratio on the surface of PMMA. Further preferably, high aspect ratio means that the ratio of the depth to the diameter of the cylindrical bore is greater than 20: 1.

Preferably, in the first step, nano-micro needles are used to punch irregularly arranged micropores on the surface of the PMMA.

Preferably, the PMMA is in a cuboid shape.

Preferably, the cross-section of the microchannel is circular or elliptical.

Aiming at the problems of deformation, insufficient strength and the like of the micro-channel inside the polymer PMMA formed by hot pressing, the invention realizes the preparation of the micro-channel structure inside the polymer PMMA with perfect performance from the aspect of energy, and provides a new scheme for the preparation of the micro-channel inside the polymer.

Drawings

FIG. 1 is a schematic diagram of the movement of PMMA at high temperature under the action of surface energy.

FIG. 2 is a flow chart of PMMA internal micro-channel formation under the action of high temperature.

FIG. 3 is a flow chart of PMMA internal microchannel formation under an irregular array of micropores.

Detailed Description

In order to make the objects, features and advantages of the present invention comprehensible, specific embodiments accompanied with figures are described in detail below. It is to be noted, however, that the drawings are designed in a simplified form and are not to scale, but rather are for the purpose of providing a convenient and clear description of the embodiments of the invention.

Example 1

A method for preparing PMMA internal micro-channels under the action of high temperature comprises the following steps:

firstly, determining basic parameters of the array micropores, and considering the PMMA surface flow influence rule under the surface energy action trend.

As shown in fig. 2, a drilling operation is performed on the rectangular silicon polymer PMMA. The micro-nano needle is used for carrying out micro-hole punching operation, parameters such as the depth H of the cylindrical hole, the diameter D of the hole, the distance Ds between the holes and the like are determined for carrying out punching operation, and the parameters are adjusted to be very important, so that the result with larger difference can be obtained when the parameters are set to be different. When micro-nano needle punching operation is carried out, the sizes of the cylindrical holes are kept consistent and are uniformly distributed on the surface of the PMMA.

And secondly, placing the punched PMMA cuboid with the micro-cylinder array holes on a high-temperature heating platform, heating to the melting point of the material of 150 ℃, enabling the PMMA in a molten state to move towards the trend of minimum energy, and enabling the perforated polymer surface to start flowing and then opening the holes to heal to form an internal microstructure. The polymer is further heated because the holes are arranged with a larger aspect ratio and a smaller distance between adjacent holes, so that the internal structures are fused with each other, as shown in fig. 1, i.e., along the direction of the smallest surface energy, and finally, a most energy stable state is achieved, as shown in fig. 2.

Example 2

As shown in fig. 3, the present embodiment is different from embodiment 1 in that: when the method is used for preparing the PMMA internal micro-channel, the micro-holes which are irregularly arranged are prepared during punching, so that the irregular internal micro-channel can be prepared according to the method, and the types of PMMA internal microstructures are greatly enriched.

Compared with the prior art, the invention has the following advantages:

firstly, the PMMA which is planted and rooted in the invention and melted under the action of high temperature flows along with the surface energy in a gradient way, the melted PMMA realizes the surface healing of the surface micro-cylindrical hole under the action of the surface energy, and the internal structure moves and is molded. The idea that the surface energy of the polymer in a molten state after heating acts on the surface flow is applied to the preparation of the internal microchannels of the polymer.

Secondly, the method for manufacturing the regularly arranged polymer PMMA internal micro-channels is to prepare the internal micro-channels on one polymer substrate, so that the problems of indefinite shape, position deviation and the like caused by the hot-pressing bonding process of two polymers are avoided.

Third, regarding the preparation of the micro-channel inside the PMMA in the prior art, the micro-channel is obtained by puncturing two sheets of PMMA materials and then is combined into one, so that the prepared micro-channel is mostly a channel with a rectangular cross section. The final cross-section is circular or elliptical, and the use of internal microchannels with circular cross-section is preferred to microchannels with rectangular cross-section.

Fourthly, the method has a simple process, shortens the manufacturing time, facilitates the preparation of the micro-channel in the PMMA, and only needs to change the position of the micro cylindrical hole during punching and then heat and deform.

The foregoing is only a preferred embodiment of the invention. The present invention is not limited to the above embodiments, and from the disclosure of the present invention, there may be variations in the embodiments according to the ideas provided by the present invention, and these variations are also considered as the protection scope of the present invention.