Plastic powder, ultrafine plastic powder, resin powder Plastic is a synthetic polymer compound, also known as polymer or macromolecule, also commonly known as plastic or resin, which can change shape freely. It is a material made by synthesizing or condensing monomer raw materials, composed of synthetic resin and fillers, plasticizers, stabilizers, lubricants, colorants and other additives.

Plastic powder

Plastic are generally divided into two types: thermoplastic and thermosetting. Thermoplastic means that the material will soften after heating, and will harden into the shape we need after cooling, and can be softened and formed repeatedly. Thermosetting will condense into a certain shape after heating, and reheating to a certain degree will destroy the internal structure of the molecule, releasing one or more elements and detaching them to become other synthetic bodies.

Source

Some plastic can be directly obtained in powder form by crystallization in the synthesis process, but most of them are about 300um rubber powder. Some plastic can also be obtained by spray granulation. About 300um rubber powder.

Plastic powder obtained by crushing process can be achieved by most plastic. Some plastic can be obtained into 200um fine powder by friction, impact, tearing, etc. of crusher at room temperature, such as plastic with relatively high glass transition temperature. However, the heat generated by most plastic during the crushing process is enough to melt them and re-bond them together, which brings difficulties to crushing. If you need to get finer plastic powder, it will be very difficult.

Crushing plastic by low-temperature crushing method can meet our requirements.

Feasibility of low-temperature crushing:

Reducing the plastic to below its brittle temperature by cold casting, while ensuring that there is enough cold casting during the crushing process to take away the heat generated during its splitting process to meet the crushing requirements. Plastic crushed by impact method in low-temperature deep-cold crushing environment are now the trend of high quality requirements.

Requirements

Fineness requirements

We generally express the powder fineness in mesh number, which is a unit of length and the size of the mesh aperture of the sieve. It indicates the number of equal parts within one inch, but the diameter of the sieve wire needs to be deducted.

1 micron----------12500 mesh

1.3 micron--------8000 mesh

2 micron----------6250 mesh

2.6 micron--------5000 mesh

5 micron----------2500 mesh

6.5 micron--------2000 mesh

10 micron---------1250 mesh

15 micron---------80 0 mesh

20 microns---------625 mesh

33 microns---------425 mesh

37 microns---------400 mesh

44 microns---------325 mesh

74 microns---------200 mesh

149 microns--------100 mesh

350 microns--------45 mesh

Coarse powder, medium powder, fine powder and ultrafine powder are used in different requirements. In plastic powder particles, coarse powder refers to powder of 5~60 mesh, and medium powder refers to powder of 60~160 mesh. Fine powder is 160 mesh to 300 mesh, and above 300 mesh belongs to ultrafine powder. However, according to the degree of easy crushing of different raw materials, the classification of coarse, medium, fine and ultrafine is different. For some compounds such as calcium carbonate, 300 mesh can only be regarded as coarse powder.

Ultrafine and uniformly sized plastic powder overcomes the shortcomings of other powder particles, the uniformity of the coating surface, and the superiority of light transmission and reflection performance, so ultrafine powder particles are becoming more and more widely used in subsequent applications.

Shape requirements

We have shape requirements for powder particles in different production processes. We usually say that tear-type powder belongs to long strips or tadpole shapes. Its light transmission and light reflection performance will lead to uneven color. Spraying on metal or other surfaces will cause unevenness, and uneven adhesion after high-temperature baking.

The powder produced by impact can be described as a stone shape, that is, there is no obvious difference between the longest end and the shortest end. This kind of powder particles can pass through the spray gun nozzle evenly, reduce the blockage of the spray gun nozzle, have a high degree of atomization, and a uniform spray surface, but coarse powder particles will affect the uniformity of the spray surface, and at the same time affect the reflection and light transmission performance, thereby affecting the appearance and adhesion.

Through the shaping of powder particles, we can get round particles like yellow sand, that is, the stone-shaped particles are rounded by shaping technology, or the water chestnuts are melted into the whole particles by temperature. This kind of powder particles are reflective, transparent and uniform. They are the future of plastic powder application.

Particle size distribution

Particle size distribution generally refers to the distribution of powder size. The narrower the distribution of plastic powder, the better the effect in subsequent production. On the contrary, the wider the distribution, the worse the effect.

How to process

1. After heating and extrusion, plastic particles are made;

2. Then through the heating of the injection molding machine, it is formed in the plastic mold to become a finished product;

3. There are also manufacturers, and some plastic powders will be directly made into finished products through injection molding machines and molds. (For example, PVC)

Application

1. Kitchen utensils: kitchen steel frame anti-corrosion coating, kitchen appliance anti-corrosion coating, non-stick pan, etc. PA, TPEF, etc.

2. Chemical anti-corrosion coating: chemical vessel anti-corrosion, chemical pipeline anti-corrosion. PA, PE, TPEF, PP, etc.

3. Hot melt adhesive powder: EVA, TPU, PA, PES, PE, etc.

4. Transfer printing: PP, PE and other composites.

5. Laser sintering rapid prototyping: PC, PA and other composites.

6. Military coating.

Plastic Industry Video