Current status and development of plastic modification technology#plastic compounding extruder#compounding extruder machine#plastic pelletizing recycling machine

Modified materials appeared in the 1990s of this century, 30 years of development makes it has the advantages of replacing steel with plastic, copper, wood, plastic and light instead of heavy, etc., and is widely used in home appliances, automobiles, high-speed railways, subways, aerospace, ships, office equipment, communication equipment, machinery and construction, and other industry sectors.

National Bureau of Statistics data show that by 2020, China's modified plastics demand reached 22.5 million t. Among them, the proportion of home appliance application is as high as 34%, the proportion of automotive applications accounted for 19%, and other areas accounted for 47%. By the end of 2022, China's modified plastics output of 28.84 million t, the total output value will exceed 415.2 billion yuan, China's modified plastics gradually become the world's largest demand market and growth power source.

1. Plastic modification technology and characteristics

Plastic modification technology refers to the process of processing polymer resins into plastic products, through filling, reinforcing, blending and other physical modification methods, block copolymerisation, radiation cross-linking and other chemical modification methods, or foaming, stretching and composite and other modification methods, to obtain the desired new material technology. This technology greatly improves the properties of plastics such as flame retardant, thermal conductivity, mechanics, wear resistance, electromagnetic shielding and so on.

2. Key to plastic modification molding technology

In the modification molding process, the formulation design and preparation process are particularly critical.
Both can greatly avoid cross-linking or degradation, and improve the performance and quality of the products. At the same time, the use of non-destructive testing technology, the use of physical methods, on the basis of not destroying the body structure and performance of the body, the modified plastic internal and external structure detection and evaluation, to ensure the product quality, use safety, reliable performance, and then improve the production process, extend the product life.

2.1 drying process

The water and volatile low molecular compounds contained in plastic particles are prone to cross-linking or degradation in the process of high temperature molding, resulting in silver lines, bubbles and other defects, affecting the quality of the product, the need to preheat and dry the plastic.

The drying temperature, time, and the thickness of the material layer will affect the drying effect. In the actual production, the direct or indirect drying method should be determined according to the hydrophilic ability, melting point, dew point, humidity, thermal conductivity and production batch. The combination of these two methods is an effective method for drying.

2.2 Screw combination and feeding technique

In the modified plastic molding equipment,  the screw structure form is the core component of the molding. The molding cycle consists of process stages such as feeding, melting, mixing and exhaust. Material, formula, performance, forming process and process stage of different, need different screw structure and local structure combination form to meet, the need for systematic research and engineering practice verification.

2.3 Facking surface treatment technique

In the process of plastic modification, a variety of polar inorganic fillers should be added, but their compatibility with organic materials with little polarity is poor. The compatibility should be improved by modification methods such as powder coating, mechanical force and chemical coating, so as to obtain excellent performance products.

2.4 Color difference and dimension appearance control technology

Using computer and other scientific instruments and operator experience combined with the method of coloring agent color matching, detection of whiteness and black spots, the use of filter impurities technology to obtain colorful and rich excellent products.

3. Peroration

The vigorous development of modified plastics, for home appliances, automobile, aerospace, high-speed rail, ships, office equipment, electric tools, mechanical construction diversity of industry development to provide strong technical support, however, these industries also for modified plastic formula design development, modified molding process and equipment put forward higher technical requirements, therefore, plastic modified molding technology research to promote the development of the plastic industry development and transformation and upgrading has positive significance.