Polypropylene (plastic pallets)
Also called: PP, PP copolymer
Polypropylene (PP) is a plastic resin used for plastic pallets. It is stiffer than HDPE at room temperature, which helps rack performance, but homopolymer PP becomes brittle in the cold, so freezer pallets use PP copolymer.
In depth: Rackable plastic pallet: runners, reinforcement and racking ratings
PP is the second main resin for plastic pallets after HDPE. It comes as homopolymer and as copolymer (blended with a small amount of ethylene), which improves impact strength at low temperature.
PP vs HDPE
| Property | Polypropylene | HDPE |
|---|---|---|
| Stiffness (flexural modulus) | Higher | Lower |
| Cold impact | Poor as homopolymer; better as copolymer | Good |
| Heat | Tolerates higher temperatures | Softens sooner |
| Typical pallet | Rackable, some hygienic and high-temperature models | Nestable, stackable, freezer |
One buyer's guide quotes PP service from about +10 °F to +220 °F (−12 to 104 °C) and a 10 to 20% price premium for high-temperature or autoclave grades. Check each model's published range.
Why it matters
Because plastic pallets creep under sustained load, a stiffer resin reduces sag when a pallet spans rack beams. That is why several rackable models use PP copolymer. For freezer use, confirm the grade is a copolymer rated for the temperature, and check drop and fork-impact performance when cold. Like other plastics, PP pallets are exempt from ISPM 15.
On a spec sheet
Material (PP, PP copolymer, HDPE or blend), virgin or recycled, reinforcement, temperature range, and static, dynamic and rack ratings with the test standard and rack orientation.
Related
- GlossaryHDPE (high-density polyethylene)HDPE (high-density polyethylene) is the most common resin for plastic pallets. It stays tough at low temperatures, which suits freezers and cold chains, but it is less stiff than polypropylene, which matters for rack deflection.
- TypesRackable plastic pallet: runners, reinforcement and racking ratingsA rackable plastic pallet is designed to sit in open-beam racking with nothing underneath. It has runners (3, 5 or 6) or a perimeter or cruciform base, often with steel reinforcement. Racking ratings for 48 × 40 in models are typically about 1,500–4,400 lb, valid only at the tested span and orientation.
- TypesPlastic pallets: types, materials, load ratings and how to buy themA plastic pallet is a molded or fabricated pallet made from HDPE or polypropylene. Types range from light nestable pallets (about 14–30 lb) to reinforced rackable pallets (about 35–70 lb). They are washable, ISPM 15 exempt and long-lived, cost several times more than wood, and carry three separate load ratings.
- GuidesPlastic pallet buying guide: styles, resins, ratings and costChoose a plastic pallet by how it is handled and stored: nestable for cheap one-way use, stackable for floor stacking, rackable for open-beam racking. Compare static, dynamic and racking ratings only when the test standard and support match. New US prices run about $40–200 (2026 estimates).
- GlossaryInjection molding (plastic pallets)Injection molding forces molten plastic into a closed steel mold under high pressure. It produces most catalog plastic pallets with tight dimensions and fast cycles, but a new pallet mold only pays off at very high volumes.
More in Materials
- GlossaryBark (on pallet lumber)Bark is the outer layer of a tree trunk. ISPM 15 requires wood packaging to be made from debarked wood, allowing only small remnants: pieces under 3 cm wide of any length, or wider pieces with a surface area under 50 cm².
- GlossaryCant (pallet lumber)A cant is a log that has been sawn flat on two or four sides. In the pallet industry it usually means the low-grade center of a hardwood log, left after grade lumber is cut from the outside, which is resawn into pallet parts.
- GlossaryComposite block (pallet)A composite block is a pallet block made from wood chips, particles or fibers bonded with resin under heat and pressure. It does not split like solid wood and, as processed wood, is exempt from ISPM 15 on its own.
- GlossaryCorrugated fiberboard (pallets and slip sheets)Corrugated fiberboard is a board made of a fluted paper medium glued between flat paper liners. It is used for boxes, and in pallet work for corrugated paper pallets, slip sheets, tier sheets and pallet runners.
- GlossaryCut stock (pallet components)Cut stock is lumber already sawn to the finished thickness, width and length of pallet parts, such as 5/8 × 3-1/2 × 40 in deckboards, ready for nailing. It is also called pallet stock or shook.
- GlossaryDouglas-fir (pallet lumber)Douglas-fir is a dense, strong softwood from western North America, also grown in Europe. It is species class 11 (Douglas-fir–larch) in the Uniform Standard and PDS, and class 33 in the European species list.
Last reviewed 2026-09-24. 218 words.