Expanded polypropylene (EPP) foams have been gaining in popularity and in application as a structural material in hobbyist radio control model aircraft. Unlike expanded polystyrene foam (EPS) which is friable and breaks easily on impact, EPP foam is able to absorb kinetic impacts very well without breaking, retains its original shape, and exhibits memory form characteristics which allow it to return to its original shape in a short amount of time. In consequence, a radio-control model whose wings and fuselage are constructed from EPP foam is extremely resilient, and able to absorb impacts that would result in complete destruction of models made from lighter traditional materials, such as balsa or even EPS foams. EPP models, when covered with inexpensive fibre glass impregnated self-adhesive tapes, often exhibit much increased mechanical strength, in conjunction with a lightness and surface finish that rival those of models of the aforementioned types. EPP is also chemically highly inert, permitting the use of a wide variety of different adhesives. EPP can be heat molded, and surfaces can be easily finished with the use of cutting tools and abrasive papers. The principal areas of model making in which EPP has found great acceptance are the fields of:
In the field of slope soaring, EPP has found greatest favor and use, as it permits the construction of radio-controlled model gliders of great strength and maneuverability. In consequence, the disciplines of slope combat (the active process of friendly competitors attempting to knock each other’s planes out of the air by direct contact) and slope pylon racing have become commonplace, in direct consequence of the strength characteristics of the material EPP.
When the cathedral on Tenerife, La Laguna Cathedral, was repaired in 2002–2014, it turned out that the vaults and dome were in a rather bad condition. Therefore, these parts of the building were demolished, and replaced by constructions in polypropylene. This was reported as the first time this material was used in this scale in buildings.
The remarkable characteristic of EPP material is that it not only has excellent performance, but also can be recycled and reused. In normal conditions, recycling EPP methods include the following:
Defoaming treatment or incinerator combustion. EPP material is safety and environmental protection. If complex other non-renewable material of different textures, such as XPE+ EPP or car roof with complexed IXPE and EPP material, it will be not separated. In this case, it will only adopt defoaming treatment or incinerator combustion.
Defoaming recycling granulation. EPP is a kind of non crosslinking material. Throughout the defoaming recycling granulation, the PP material can use normally. To the EPP that complexed the other same texture material, such as TPO+EPP and TPO+PP+EPP, it can adopt this case to deal with. Using this granulation method will not harm to the environment.
Don’t change the geometrical state of the EPP foaming material recycling methods. Compared with ordinary PP materials, the value of foamed EPP material is more expensive. If adopts the granulation method, it will be uneconomical. Specifically, this case has the following advantages:
Make full use of valuable resources. Now, EPP foam particle material is also dependent on imports, the price is expensive. Adopting defoaming treatment or incinerator combustion means a lot of waste. Recycling EPP material can maximize the value of its use.
Save a lot of energy. Recycling the EPP that cannot change its physical state, it will save much electric energy and manual work.
Greatly improve the economic benefits of EPP manufacturing enterprises. Both can save costs and will not cause pollution to the environment.
Compared with 100% of the new materials, the performance of the recycled EPP inevitably has certain difference, so the proportion of its incorporation to less than 10% is appropriate, so as to ensure the performance of the use of products. For EPP components directly subjected to impact loading, the incorporation of recycled EPP reduction particles is generally not allowed. Normally, EPP components in car, such as luggage subplate, foot rest, tool cabinet and so on, in case of without affecting the appearance and performance, the usage amount of the EPP recycling granule can suitably mix according to the recommended proportion.
Now we use the EPP Compactor to manage as the first step of recycling EPP material,it can reduce the size of the foam EPP into blocks to make the material easy to transport. Now most of the customer sell the material to other country to recycle the material into pellets.
Our EPP compactor first crusher the EPP box into 50mm size small pieces and then fall down to a strong screw , after that the extruder will extrude the material into a sharp mold to make the material into blocks ,it can reach 300kg/cubic meter.Also you can use the hot melting machine to recycle the EPP material , the same as the normal compactor ,the material will be crushed first and then into a heated barrel ,then extrude with the screw into bloks.the density can reacy 600kg/cubic meter.
Then you can easily to transport to another place ,increase the efficiency of transportation ,and it can also increase the capacity in the next step of recycling.