Key points of plastic modification formula

1. Selection of resin

The selected target resin has the closest performance to the target to be modified, and the determination of the target resin will make the target selection more deterministic.

2. Selection of additives

Different types of auxiliaries have different target performance, the auxiliaries added to the system can fully its expected function, and reach the target specified indicators.

3. Mix well

Uniform mixing is the basic requirement of plastic formulation modification, and it also requires uniform distribution of additives in the formation of resin.

4. Selection of formula

The processability of the formula is that the modified plastic formula has the processability, which is to meet the requirements of the molding plastic modification and the molding of the product.

Common methods of plastic modification

1. Add modification

Add small molecule inorganic matter or organic matter; Polymer addition

2. Modification of morphology and structure

This method is mainly modified for the resin shape and structure of the plastic itself. The usual method is to change the crystal state of plastics, crosslinking, copolymerization, grafting and so on.

3. Composite modification

Composite modification of plastics refers to the method of combining two or more layers of films, sheets and other materials together to form a multilayer film, sheet and other materials by adhesive or hot melt. The composite modification of plastics is actually the extremity of the plastic blend modification method, and can also be regarded as a special plastic blend modification.

4. Surface modification

Plastic surface modification refers to a kind of modification method that changes the surface properties of plastic products by physical or chemical methods. The purpose of plastic surface modification can be mainly divided into two categories: one is the modification of direct application, and the other is the modification of indirect application.

Guangzhou OTEM Engineering Plastics Co., Ltd. has more than 20 years of plastic modification production and manufacturing experience, with more than 2,000 square meters of physical processing factory, but also has CNC, vulcanization machine, spark machine and other professional production equipment, as well as a professional design team can bring customers satisfactory products and services.

General production process of modified plastics

1. Raw material preparation

First of all, we need to prepare raw materials, including plastic resins, toners and additives. According to different requirements and product specifications, different raw materials and auxiliary materials are selected for mixing.

2. Mixing and processing

The selected plastic resin and additives are mixed in the mixing equipment, so that the raw materials and color powder, additives, etc., are fully mixed and uniform;

3. Extrusion processing

Through the twin-screw extruder, the mixed resin material is melted, extruded into strips, cooled and cut into uniform plastic particles with the granulator;

4. Homogenize

The finished plastic particles are homogenized and mixed in the homogenizing barrel to make the same batch of materials, properties and colors uniform;

5. Inspection and packaging

In the production process, in order to ensure the stability of the material, it is necessary to test the one-time energy and color every 2 hours; It is then packaged and labeled for easy storage and transportation.

Causes of broken strips during processing of modified plastics

1, the head pressure is too high (including die blockage, too much filter, too low head temperature, etc.), resulting in increased backflow and increased carbonization, carbonization is taken out to the material bar, under the action of traction, resulting in broken bar;

2. Extruder local overheating, resulting in increased carbonization, carbonization is taken out to the bar, under the action of traction, resulting in broken bar;

3. The screw shear is too strong, causing the local carbonization of the material to increase, and the carbonized material is taken out to the material strip, causing the broken strip under the action of traction;

4. Long service life of the machine, wear of the screw and barrel, increase the gap, increase the backflow, increase the carbonization of the cylinder wall, with the extension of extrusion time, the carbonization is gradually taken out to the bar, under the action of traction, resulting in broken bar;

5. Vacuum or natural exhaust port (including gasket and dead Angle here) is not cleaned for a long time, the existing carbonized matter is taken to the material strip, under the action of traction, resulting in broken strip;

6. The head die (including the discharge port and the dead Angle inside the head) is not cleaned up, and the mouth die contains carbonized substances or impurities which are brought to the material strip, causing the broken strip under the action of traction;

7. The time interval for replacing the filter screen is too long, the filter screen is blocked, and the material cannot come out, resulting in broken strips.