GL-75 Plastic Foam Sheet Extruder
【a brief introdction】
Foam plastic has the advantages of light weight, heat insulation, buffering, insulation, anticorrosion, and low price, so it has been widely used in daily necessities, packaging, industry, agriculture, transportation, military industry, and aerospace industry. China ’s foam has been used since the 1990s. The development of plastics is very rapid. The main varieties are polyurethane (PU) flexible and rigid foams, polystyrene (PS) foams and polyethylene (PE) foams. However, polyurethane foam has isocyanate residues that are harmful to the human body during foaming.
Plastic foam sheet extruder (pictured)
Foam plastic has the advantages of light weight, heat insulation, buffering, insulation, anticorrosion, and low price, so it has been widely used in daily necessities, packaging, industry, agriculture, transportation, military industry, and aerospace industry. China ’s foam has been used since the 1990s. The development of plastics is very rapid. The main varieties are polyurethane (PU) flexible and rigid foams, polystyrene (PS) foams and polyethylene (PE) foams. However, polyurethane foam has isocyanate residues that are harmful to the human body during the foaming process, and the foaming material cannot be recycled. In the process of polystyrene (PS) foaming, chlorofluorocarbons or butane are usually used, which has an adverse impact on the environment, the product is difficult to degrade, and it is easy to form "white pollution". Environmental protection organizations have decided to stop using PS foamed products. . Cross-linked polyethylene foam has low rigidity and a high use temperature of 80 ° C.
Compared with the above three kinds of foam plastics, polypropylene foam materials have many advantages:
1) Polypropylene (PP) has better rigidity than polyethylene (PE). The flexural modulus of PP is about 1.52Gpa, PE is only 207Mpa, and chemical resistance is similar to PE.
2) The glass transition temperature of polypropylene is lower than room temperature, the impact resistance is better than PS, and compared with the difficult recycling of PS foam, polypropylene foam is an environmentally friendly material.
3) Polypropylene has high heat distortion temperature and can be used in some high temperature fields. Foamed polypropylene can generally withstand high temperatures of 130 ° C, which is much higher than the high use temperature of polyethylene foam, which is 80 ° C. The closed cell structure does not affect its thermal conductivity due to moisture, so it can be used as a thermal insulation material.
4) Good low temperature characteristics: The products show good performance even at -30 ℃.
5) Energy absorption: Because PP foamed products have good energy absorption characteristics, they have excellent compression energy absorption performance. Widely used in automotive bumper energy processing systems and other anti-collision energy-absorbing components.
6) Dimension and shape recovery stability: PP foamed products will quickly return to their original shape after repeated continuous impacts and flexural deformation without permanent deformation.
7) Light weight and can be used repeatedly: The density of PP foam products can reach a very low level, so it can greatly reduce weight. At the same time, PP foam products have good flexibility, can be used repeatedly, and are not easily broken; Decomposed, the product does not contain toxic and harmful ingredients to the human body, burning does not produce toxic substances.
8) Has good surface protection and sound insulation performance: PP foamed products are semi-rigid formed, with moderate hardness and softness, will not scratch or bump the objects in contact with them, and have good surface protection.
Polypropylene resin has the characteristics of light weight, rich source of raw materials, superior performance-price ratio, excellent heat resistance, chemical resistance, and easy recycling. It is a universal thermoplastic resin with fast output growth in the world. Become a large-volume resin variety. However, the applications are mainly woven products and agricultural films. The PP resin industry faces the problems of a single consumption structure, weak demand and low product grades. All resin manufacturers are actively adjusting their production ideas, developing and producing special materials that are marketable, high quality, and high added value, so that PP has greater application value and economic benefits. Among them, the research and development of polypropylene foam has also become a hot spot in recent years. Although polypropylene foam products have good performance and application prospects, the development of polypropylene foam is very difficult. At present, there is no relevant and industrializable product in China. Core technologies. At present, some developed countries are vigorously developing and using green packaging materials as an alternative to expanded polystyrene.
Plastic foam sheet extruder (pictured)
PP foam materials for automotive parts have become increasingly important in recent years. In addition to high heat resistance, high impact energy absorption capacity, good resilience and thermoformability, PP foam is also an important factor for recycling. This makes it possible to implement the scheme of completely manufacturing parts using PP. For example, in the instrument panel, GMT or talc reinforced PP is used to manufacture the bracket, PP foam is used as a soft elastic intermediate layer, and a soft sealing film is used as the skin. With this solution, after the car is scrapped, the plastic parts of the car can be reused for lower-level products such as wheel arch linings after being disassembled, washed, and re-pelletized. However, due to the high cost and complicated process, this process is limited. All these problems will be solved if the foamed PP with smooth surface is made by thermoforming and bonded with the injection-molded PP or ABS base layer. Extruded PP foam sheet can be used in the production of water barriers or sound insulation panels for automobile doors, rear engine compartments for luxury cars. Rigid PP foam board reinforced with glass felt can be used to produce car engine covers, load-bearing floors and spare tire covers. Due to its good thermal weldability, foamed PP can be used as roof panels for automobiles; due to its hot workability, cross-linked foamed PP will be further used in components such as control boxes and shock-proof panels. Foamed PP sheet and inner layer materials such as PP and ABS, surface materials such as PVC are bonded by adhesive or heating. After vacuum forming, carpet support materials, sun visors, sound insulation panels, door linings and luggage racks can be made. Foamed PP can also manufacture steering wheels, luggage compartment linings, and barriers to air-conditioning steam, side guards, door inner panels, energy-absorbing protective pads, cushions, headrests, tool boxes, and more. In these areas where higher operating temperatures are required, foamed PP has advantages over foamed PE, because the latter can only be used at temperatures below 80 ° C. Due to the high heat resistance of PP, it is widely used abroad to replace the PS foam sheet where the heat resistance cannot meet the requirements, such as insulation materials for 90 ° C to 120 ° C heat carrier cycle batteries, engine rooms and workshops. Insulation materials, heat insulation jackets for heaters, and places in the car that must be insulated, such as sun visors, insulation panels on instruments, and places where the temperature between two doors is likely to rise. In short, foamed PP can be used in all parts where heat resistance is encountered when using PE foam.