The mixing of plastics is to use an effective means or equipment to process multi-component raw materials into more uniform and practical particles. This process needs to go through, raw material pretreatment, feeding, plasticization, mixing, dispersion and distribution, exhaust, molding, etc. Some raw materials may occur chemical or physical reactions in the process. For twin screw machine, it has friendly operability, applicability and versatility.
Plastic compounding can be traced back to the birth of celluloid in 1870.
In 1931, the German Farben Company industrialized production of polyvinyl chloride. The large-scale production and application of PVC has promoted the development of plastic compounding technology. Since the production process of soft polyvinyl chloride plastic products evolved from the rubber industry, the compounding of polyvinyl chloride plastics mostly uses rubber equipment.
In the early 1940s, the extrusion compounding method of polyvinyl chloride pellets began to be used. In 1948, the United States Monsanto (Monsanto) developed a dry blending method for polyvinyl chloride.
Since then, with the development of modification technologies such as plastic blending, filling, and reinforcement, the compounding technologies of a variety of general-purpose and engineering plastics have also developed day by day.
By the late 1970s, 60% of the world’s thermoplastics needed to be compounded before processing. At the same time, research and development of compounding equipment was also developed.
Depending on the form of the compound, the plastic compounding process is also different, but the process is similar, including:
①Measuring: accurate weighing of various raw materials and materials.
②Mixing: In the mixing equipment of different forms and structures, the various components are uniformly dispersed and mixed.
③Plastification: use internal mixer, open mill or plasticizing extruder (see plastic machinery) to melt and homogenize the mixed components.
④Separation: Eliminate volatile components, air and impurities brought in by the original material and materials.
⑤Pelletizing: If pellets need to be made, use various pelletizers to cut into pellets of a certain size and shape.
In plastic compounding, in addition to the compatibility of the formula and different components, the compounding process and the selection of equipment also play an important role in the quality of the compound. In order to design special compounding materials with precise processing characteristics to meet the requirements of diversified plastic processing and application, plastic compounding has evolved from a simple mixing operation to a complex and delicate process.
In recent years, the development of plastic compounding technology has been committed to improving production efficiency, improving the quality of compounding materials, reducing labor consumption, facilitating operation, and ensuring production safety and environmental sanitation. The plastic compounding process is becoming more continuous, airtight, large-scale, high-speed and automated. An automated professional plastic compounding plant controlled by computer programs has emerged.
In addition, the deepening of the research on the mixing mechanism and the selection of plastic additives and their action mechanism is promoting the advancement of plastic compounding technology and equipment.
Nanjing KY Chemical Machinery Co., Ltd. is committed to the design, production, manufacture and sales of twin-screw extruders, which are widely used in the fields of polyolefin, engineering plastics, color masterbatch, functional masterbatch, elastomer, biodegradation, wire and cable, reactive extrusion, desorption, ultra-high molecular weight polyethylene, lithium battery separator, etc. With the same process, KY can provide you with a perfect solution.
KEYA Twin Screw Extruder