Case Studies

Plastic Pallet Raw Materials

Raw material options
 
Polypropylene (PP) is in many respects similar to high-density polyethylene. However, instead of forming a long polymer chain made up of repeating –CH2-components, the polypropylene molecule has a series of CH3 groups that hang off the main carbon backbone. PPs are considered isotactic PPs, with the CH3 groups oriented on one side of the carbon backbone. This orientation creates a greater degree of cystallinity, making PP stiffer and more resistant to creep (the tendency to flow under stress) compared to PE.
The nominal pore size for PP ranges from 80 to 150 micrometers. PP is highly resistant to most acids and alkalis and is resistant to most organic solvents below 80°C (176°F). When not stressed, PP may be used at temperatures ranging from 93°C to 149°C (200°F to 300°F). Further, PP can normally be subjected to steam sterilization.
 
Minimum working temperature: +4°C
 
In general products made of PP are more rigid and more brittle than products  made from HDPE.
 
 
High-Density Polyethylene (HDPE)
With a linear molecular structure of repeating –CH2-CH2-units, PE is a semi-crystalline polymer. In general, PE is considered a strong, lightweight thermoplastic with very good chemical resistance. Further, the polymer elongates before breaking, which enhances the toughness of porous parts made from PE. Products made from standard polyethylene grades typically have pore size diameters ranging from 7 to 150 micrometers. However, these nominal values can be increased to 300 micrometers with special blends.

Polyethylene is resistant to concentrated acids, alkalis and many organic solvents. Most polyethylene grades are suitable for use in continuous service at temperatures up to 82°C (180°F) and intermittently at 116°C (240°F). If not stressed, PE grades are stable at 100°C (212°F) in continuous service applications.  HDPE can be subjected to steam sterilization.
 
Minimum working temperature: -60°C
 
In general products made of HDPE are less rigid and less brittle than products made from PP.
 
Simax's standard plastic pallets are made from 100% recycled post-consumer raw material, reinforced with structural foam technology for extra strength yet lighter weight, giving improved load-bearing capacity and value-for-money.