What are the new technologies in rotational molding?

What are the new technologies in rotational molding?

The new technologies of roto-molding technology are mainly as follows:

Roto-molding foaming molding technology
Principle: During the roto-molding process, a foam structure is formed inside the product through specific foaming materials and processes to improve the thermal insulation, heat insulation, shock absorption and other properties of the product.
Advantages: Compared with traditional roto-molded products, foamed roto-molded products are lighter in weight while maintaining a certain strength, have better thermal insulation effect, can effectively reduce heat transfer, and are suitable for fields with high requirements for thermal insulation performance, such as refrigerators, hot water tanks, etc.
Application: The technology invented by Shinny Case Company of Japan uses polyethylene foam in the inner layer of the product and polyethylene or polypropylene in the outer layer. The foam is formed by pre-foaming masterbatch and can be used in refrigerators, floating facilities, sports equipment, etc.
Cross-linked polyethylene roto-molding technology
Principle: The linear polyethylene molecular chains are connected into a mesh structure through a cross-linking agent, thereby improving the performance of polyethylene.
Advantages: The toughness, rigidity, long-term use temperature and environmental stress cracking resistance of cross-linked polyethylene are greatly improved, and it has excellent impact resistance, which can broaden the application range of PE materials.
Application: It can be used to manufacture chemical solvent storage tanks, solar water heaters, electric water heaters, heat pump air conditioners, water heater tanks, chemical pipelines and engineering vehicle tanks, etc.
New resin rotational molding technology
Principle: Synthetic resin manufacturers continue to improve molecular design, catalyst formulations and production processes to develop new resins that are more suitable for rotational molding.
Advantages: For example, the two high-performance rotational molding grade HDPE resins GX5002 and GX5003 launched by Lyondell Basell have excellent low-temperature impact resistance and environmental stress cracking resistance, as well as good creep resistance. The melt fluidity and rigidity are well balanced, and thin-walled products can be manufactured, reducing the weight of products, with a wider processing window and a shorter processing cycle.
Application: Mainly used in tool boxes, storage tanks, hollow containers, bulk liquid intermediate storage tanks, furniture, toys and sports equipment, etc.
Automation technology of rotational molding equipment
Principle: Automatic feeding, heating, cooling, demolding and other operations in the rotational molding process are realized through an automated control system.
Advantages: Improve production efficiency, reduce production costs, shorten roto-molding time, increase output and product design freedom, reduce polymer internal stress, and improve product size and stability.
Application: The fully automatic electric heating roto-molding technology launched by Persico s.p.a. in Italy can produce products such as water tanks, fire extinguisher boxes, rowing boats, toys, roofs and pallets.
In-film pressurization and cooling technology
Principle: During a certain period of the heating and cooling stages, the mold is inflated for pressurization, or the in-film cooling technology is used to reduce the heating and cooling time.
Advantages: It can shorten the processing cycle, reduce bubbles in the product, improve the toughness of the product, reduce the temperature gradient between the inner and outer walls of the mold and the plastic product, and reduce the warping caused by the difference in the crystal structure of the product caused by the temperature difference.
Application: It can be used in the production of roto-molded products with high requirements for product size accuracy and surface quality, such as some large industrial containers, automotive parts, etc.
Infrared microwave heating technology
Principle: Use the characteristics of infrared and microwaves to heat the mold and plastic raw materials to improve heating efficiency and uniformity.
Advantages: Compared with traditional heating methods, infrared microwave heating technology can heat molds and plastic raw materials more quickly and evenly, thereby improving the efficiency and quality of rotational molding and reducing energy consumption.
Application: Suitable for the production of various rotational molded products, especially some complex-shaped products that require high heating uniformity.