阅读说明：本技术 一种核壳结构聚苯乙烯泡沫吸波球及其制备方法 (Polystyrene foam wave-absorbing ball with core-shell structure and preparation method thereof ) 是由 王军耀 于 2021-06-10 设计创作，主要内容包括：本申请涉及新材料制备技术领域,具体涉及一种核壳结构聚苯乙烯泡沫吸波球及其制备方法,旨在解决现有工艺难以实现包裹层厚度的均匀性,制备出来的吸波球成型难度大,吸收一致性差的问题,其技术要点在于：该核壳结构聚苯乙烯泡沫吸波球包括吸波球和均匀包覆在其表面的一层吸波阻燃介质,所述吸波球包括通过共发泡制得的吸波砂、聚苯乙烯原料粒子,所述吸波阻燃介质包括固体分散剂、导电剂及阻燃剂。本发明中吸波球可以应用于制造硬质泡沫角锥形吸波材料、水泥基吸波材料及其他填充型吸波材料,由于形成了均匀的核壳结构,吸收效率高,阻燃性能优异。(The application relates to the technical field of new material preparation, in particular to a polystyrene foam wave-absorbing ball with a core-shell structure and a preparation method thereof, aiming at solving the problems that the existing process is difficult to realize the uniformity of the thickness of a coating layer, the prepared wave-absorbing ball is high in forming difficulty and poor in absorption consistency, and the technical key points are as follows: the wave-absorbing polystyrene foam wave-absorbing ball with the core-shell structure comprises a wave-absorbing ball and a layer of wave-absorbing flame-retardant medium uniformly coated on the surface of the wave-absorbing ball, wherein the wave-absorbing ball comprises wave-absorbing sand and polystyrene raw material particles prepared through co-foaming, and the wave-absorbing flame-retardant medium comprises a solid dispersing agent, a conductive agent and a flame retardant. The wave-absorbing ball can be applied to manufacturing hard foam pyramid wave-absorbing materials, cement-based wave-absorbing materials and other filling type wave-absorbing materials, and has high absorption efficiency and excellent flame retardant property due to the formation of a uniform core-shell structure.)

1. The polystyrene foam wave-absorbing ball with the core-shell structure is characterized by comprising a wave-absorbing ball and a layer of wave-absorbing flame-retardant medium uniformly coated on the surface of the wave-absorbing ball, wherein the wave-absorbing ball comprises wave-absorbing sand and polystyrene raw material particles which are prepared through co-foaming, and the wave-absorbing flame-retardant medium comprises a solid dispersing agent, a conductive agent and a flame retardant.

2. The polystyrene foam wave-absorbing ball with the core-shell structure of claim 1, wherein the wave-absorbing sand is a composite of an absorbent, a flame retardant and a polymer matrix, the primary particle size is 0.5-1mm, and the melting point is 70-80 ℃.

3. The polystyrene foam wave-absorbing ball with the core-shell structure of claim 1, wherein the high-dispersion matrix is chlorinated paraffin; the absorbent is at least one of high-conductivity carbon black, nano graphite or iron-silicon-aluminum powder; the flame retardant is at least one of expanded graphite, ammonium polyphosphate, pentaerythritol or aluminum hydroxide.

4. The polystyrene foam wave-absorbing ball with the core-shell structure of claim 3, wherein the wave-absorbing sand consists of the following components in percentage by weight:

45-55% of chlorinated paraffin, 15-20% of high-conductivity carbon black, 4-8% of ammonium polyphosphate, 4-8% of expanded graphite and 8-10% of aluminum hydroxide.

5. A preparation method of a polystyrene foam wave-absorbing ball with a core-shell structure is characterized in that the polystyrene foam wave-absorbing ball with the core-shell structure based on any one of claims 1 to 4 comprises the following steps:

firstly, manufacturing wave-absorbing sand for co-foaming;

secondly, putting the wave-absorbing sand and the polystyrene raw material particles into a foaming machine for co-foaming;

thirdly, obtaining the wave absorbing ball by hot air and fluidized bed drying;

and fourthly, coating a layer of wave-absorbing flame-retardant medium on the surface of the wave-absorbing ball to obtain the polystyrene foam wave-absorbing ball with the core-shell structure.

6. The preparation method of the polystyrene foam wave-absorbing ball with the core-shell structure according to claim 5, wherein the concrete process of the first step is as follows: firstly, melting a polymer matrix in an internal mixer, and then adding a flame retardant and a wave absorbing agent into the internal mixer for mixing; the total mixing time is 1-2 hours, the mixing temperature is set to 90-100 ℃, and the mixing speed is 20-30 revolutions per minute.

7. The preparation method of the polystyrene foam absorbing ball with the core-shell structure as claimed in claim 6, wherein the polystyrene foam absorbing ball is granulated by a granulator after the materials are mixed and cooled, and the polystyrene foam absorbing ball is sieved by a 20-mesh sieve during granulation.

8. The preparation method of the polystyrene foam wave-absorbing ball with the core-shell structure according to claim 5, wherein the specific process of the second step is as follows: the mass ratio of the polystyrene raw material particles to the wave-absorbing sand is 100: 15-25 ℃, the foaming temperature is 90 +/-5 ℃, and the foaming time is at least 10-15 minutes.

Technical Field

The application relates to the technical field of new material preparation, in particular to a polystyrene foam wave-absorbing ball with a core-shell structure and a preparation method thereof.

Background

With the improvement of the technological level, wave-absorbing materials applied to the electric wave darkroom industry in China are more and more in types, but the general development direction is superior in electrical performance, high cleanliness, certain power capacity and durability. Based on these trends, a great number of cube-corner absorbing materials, including polystyrene and polypropylene rigid foams, using rigid foams as base materials are adopted by foreign darkroom suppliers. Due to the disadvantages of complex foaming process, low flame-retardant grade, high cost and the like of polypropylene materials, few manufacturers are adopted, and polystyrene rigid foam materials are widely adopted, such as TDK in Japan, Comtest in the Netherlands and ETS in the United states.

At present, domestic manufacturers generally adopt a dispersion wrapping method, for example, in Nanjing Lopu 201310340537.8 patent, a coating wrapping process with styrene-acrylic emulsion as a film-forming agent is adopted, in Dalian Dongxin 201610947347.6 patent, pure acrylic emulsion is adopted as a wrapped matrix emulsion, the processes of the two are the same, and both adopt a process of foaming firstly and wrapping secondly, so that the uniformity of the thickness of the wrapping layer is difficult to realize, and the wave-absorbing ball prepared by the process has high molding difficulty and poor absorption consistency.

Disclosure of Invention

The application mainly aims to provide a polystyrene foam wave-absorbing ball with a core-shell structure and a preparation method thereof, and aims to solve the problems that the uniformity of the thickness of a wrapping layer is difficult to realize, the prepared wave-absorbing ball is difficult to form, and the absorption consistency is poor in the prior art.

The technical purpose of the application is realized by the following technical scheme:

the polystyrene foam wave-absorbing ball with the core-shell structure comprises a wave-absorbing ball and a layer of wave-absorbing flame-retardant medium uniformly coated on the surface of the wave-absorbing ball, wherein the wave-absorbing ball comprises wave-absorbing sand and polystyrene raw material particles prepared through co-foaming, and the wave-absorbing flame-retardant medium comprises a solid dispersing agent, a conductive agent and a flame retardant.

Optionally, the wave-absorbing sand is a composite of an absorbent, a flame retardant and a polymer matrix, the primary particle size is 0.5-1mm, and the melting point is 70-80 ℃.

Optionally, the high dispersion matrix is a chlorinated paraffin; the absorbent is at least one of high-conductivity carbon black, nano graphite or iron-silicon-aluminum powder; the flame retardant is at least one of expanded graphite, ammonium polyphosphate, pentaerythritol or aluminum hydroxide.

Optionally, the wave-absorbing sand comprises the following components in percentage by weight:

45-55% of chlorinated paraffin, 15-20% of high-conductivity carbon black, 4-8% of ammonium polyphosphate, 4-8% of expanded graphite and 8-10% of aluminum hydroxide.

The preparation method of the polystyrene foam wave-absorbing ball with the core-shell structure comprises the following steps:

firstly, manufacturing wave-absorbing sand for co-foaming;

secondly, putting the wave-absorbing sand and the polystyrene raw material particles into a foaming machine for co-foaming;

thirdly, obtaining the wave absorbing ball by hot air and fluidized bed drying;

and fourthly, coating a layer of wave-absorbing flame-retardant medium on the surface of the wave-absorbing ball to obtain the polystyrene foam wave-absorbing ball with the core-shell structure.

Optionally, the specific process of the first step is as follows: firstly, melting a polymer matrix in an internal mixer, and then adding a flame retardant and a wave absorbing agent into the internal mixer for mixing; the total mixing time is 1-2 hours, the mixing temperature is set to 90-100 ℃, and the mixing speed is 20-30 revolutions per minute.

Optionally, after the mixing is finished, discharging and cooling, granulating by using a granulator, and sieving by using a 20-mesh sieve during granulation.

Optionally, the specific process of the second step is as follows: the mass ratio of the polystyrene raw material particles to the wave-absorbing sand is 100: 15-25 ℃, the foaming temperature is 90 +/-5 ℃, and the foaming time is at least 10-15 minutes.

Compared with the prior art, the invention has the following beneficial effects:

(1) the hard polystyrene foam wave-absorbing ball has an even core-shell structure, and is very favorable for later-stage molding.

(2) The core-shell structure which is uniformly wrapped is more beneficial to absorbing electromagnetic waves.

(3) Through the co-foaming process, the wave-absorbing sand can be directly wrapped on the pre-foaming particles during foaming, so that the process steps are simplified, and the efficiency is greatly improved.

Detailed Description

In order to make the technical solutions in the embodiments of the present application better understood, the technical solutions in the embodiments of the present application are clearly and completely described below, and it is obvious that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It is noted that the terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

These terms are used primarily to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation.

Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meaning of these terms in this application will be understood by those of ordinary skill in the art as appropriate.

In addition, the term "plurality" shall mean two as well as more than two.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail with reference to examples.

Example 1:

a polystyrene foam wave-absorbing ball with a core-shell structure comprises a wave-absorbing ball and a layer of wave-absorbing flame-retardant medium uniformly coated on the surface of the wave-absorbing ball, wherein the wave-absorbing ball comprises wave-absorbing sand and polystyrene raw material particles prepared through co-foaming, and the wave-absorbing flame-retardant medium comprises a solid dispersing agent, a conductive agent and a flame retardant. Wherein the wave-absorbing sand is a compound of an absorbent, a flame retardant and a polymer matrix, the primary particle size is 0.5-1mm, and the melting point is 70-80 ℃. Specifically, the high dispersion matrix is chlorinated paraffin; the absorbent is at least one of high-conductivity carbon black, nano graphite or iron-silicon-aluminum powder; the flame retardant is at least one of expanded graphite, ammonium polyphosphate, pentaerythritol or aluminum hydroxide.

In the embodiment of the invention, preferably, the wave-absorbing sand comprises the following components in percentage by weight:

55% of chlorinated paraffin, 20% of high-conductivity carbon black, 8% of ammonium polyphosphate, 7% of expanded graphite and 10% of aluminum hydroxide.

The prepared polystyrene foam wave-absorbing ball with the core-shell structure has uniform surface coating and good particle size consistency, is very suitable for a later-stage foam molding process, can be applied to manufacturing hard foam pyramid wave-absorbing materials, cement-based wave-absorbing materials and other filling type wave-absorbing materials, and has high absorption efficiency and excellent flame retardant property due to the formation of the uniform core-shell structure.

Example 2:

a preparation method of a polystyrene foam wave-absorbing ball with a core-shell structure comprises the following steps:

firstly, manufacturing wave-absorbing sand for co-foaming;

specifically, the chlorinated paraffin is melted in an internal mixer, and then the conductive agent high-conductivity carbon black, the flame retardant ammonium polyphosphate APP-2, the flame retardant expanded graphite and the flame retardant aluminum hydroxide are added into the internal mixer for mixing; the total mixing time is 1 hour, the mixing temperature is set to be 90 ℃, and the mixing rotating speed is 30 revolutions per minute; after mixing, discharging and cooling, granulating by using a granulator, and sieving by using a 20-mesh sieve during granulation;

secondly, putting the wave-absorbing sand and the polystyrene raw material particles into a foaming machine for co-foaming;

specifically, the mass ratio of the polystyrene raw material particles to the wave-absorbing sand is 100: 20, the foaming temperature is 90 ℃, and the foaming time is at least 10 minutes;

thirdly, obtaining the wave absorbing ball by hot air and fluidized bed drying;

and fourthly, coating a layer of wave-absorbing flame-retardant medium including a solid dispersing agent, a conductive agent and a flame retardant on the surface of the wave-absorbing ball to obtain the polystyrene foam wave-absorbing ball with the core-shell structure.

Through the co-foaming process, the wave-absorbing sand can be directly wrapped on the pre-foaming particles during foaming, so that the process steps are simplified, the efficiency is greatly improved, the prepared polystyrene foam wave-absorbing ball with the core-shell structure is uniform in surface wrapping, the particle size consistency is good, the polystyrene foam wave-absorbing ball is very suitable for the later-stage foam molding process, and can be applied to manufacturing hard foam pyramid wave-absorbing materials, cement-based wave-absorbing materials and other filling type wave-absorbing materials.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.