Table of Contents
Reviewed and updated by ICD - Week 42/2026
PP and HDPE are the two dominant materials for industrial plastic products - from pallets and crates to pipes and containers. Both are polyolefins with excellent chemical resistance, but they have distinct differences that make each better suited to specific applications.
PP vs HDPE: key differences at a glance
| Property | PP (Polypropylene) | HDPE (High-Density Polyethylene) |
|---|---|---|
| Density | 0.89-0.91 g/cm3 (lighter) | 0.93-0.97 g/cm3 |
| Melting point | 160-168 degrees C | 120-135 degrees C |
| Continuous service limit | Up to 100 degrees C | Up to 82 degrees C |
| Cold temperature limit | Down to -20 degrees C (standard)* | Down to -40 degrees C |
| Tensile strength | 30-40 MPa | 20-37 MPa |
| Flexural modulus (stiffness) | 1,000-1,600 MPa | 800-1,600 MPa |
| Impact resistance (standard) | Moderate (brittle at low temp) | Good (ductile to -40 degrees C) |
| Chemical resistance | Excellent | Excellent |
| UV resistance (unmodified) | Poor - requires UV stabilizer | Poor - requires UV stabilizer |
| Resin code | 5 | 2 |
| Food contact approval | Yes (FDA, EU 10/2011) | Yes (FDA, EU 10/2011) |
*PP impact copolymer grades perform to -30 degrees C. Standard homopolymer PP becomes brittle below -20 degrees C.
Where PP wins over HDPE
- Higher heat resistance: PP’s melting point of 160 degrees C and continuous service limit of ~100 degrees C make it suitable for hot-fill applications, autoclave sterilization, and warm industrial environments where HDPE would deform.
- Better fatigue resistance: PP has superior resistance to repeated flexing and cyclic loading - ideal for integral hinges and living hinge applications (like lid hinges on containers).
- Lower density: At 0.89-0.91 g/cm3, PP is lighter than HDPE (0.93-0.97 g/cm3), advantageous where weight matters.
- Higher rigidity at comparable thickness: PP’s flexural modulus is generally higher, giving stiffer parts for the same wall thickness.
Where HDPE wins over PP
- Cold temperature performance: HDPE remains ductile and impact-resistant to -40 degrees C, while standard PP becomes brittle below -20 degrees C. For cold chain and frozen storage applications, HDPE is the preferred choice.
- ESCR (Environmental Stress Crack Resistance): High-MW HDPE grades have outstanding ESCR - resistance to cracking under combined stress and chemical exposure. Critical for chemical containers and fuel tanks.
- Processing for very large parts: HDPE blow moulding grades are well-established for large hollow containers (1000L IBC tanks, 200L drums), where PP is less common.
- Lower raw material cost: HDPE is typically slightly less expensive than PP, though this varies with crude oil markets.
PP vs HDPE for plastic pallets
Both PP and HDPE are used for industrial plastic pallets. The choice depends on the specific application:
| Application scenario | Better choice | Reason |
|---|---|---|
| General ambient warehouse (20-40 degrees C) | Either - cost decides | Both perform well in this range |
| Cold chain / frozen storage (-20 to 0 degrees C) | HDPE | Maintains ductility to -40 degrees C |
| Hot environments / near ovens (60-100 degrees C) | PP | Higher continuous service limit |
| Food manufacturing (wash-down, sterilization) | PP | Autoclave-compatible, higher heat |
| Chemical plant (acid / alkali exposure) | HDPE (HMW grade) | Superior ESCR for chemical environments |
| Export pallet (weight-sensitive shipping) | PP | Lighter density saves freight cost |
ICD Vietnam distributes both PP and HDPE plastic pallets to match specific customer requirements. Contact us to discuss which material is optimal for your logistics environment.
Similarities between PP and HDPE
- Both are polyolefins - non-toxic, odourless, chemically inert
- Both are approved for direct food contact under FDA and EU regulations
- Both have excellent resistance to acids, alkalis, and common solvents
- Both are thermally recyclable (codes 5 and 2 respectively)
- Both require UV stabilizer additives for long-term outdoor applications
- Both are among the highest-volume commodity plastics globally
Frequently Asked Questions
1. Is PP or HDPE stronger?
PP has higher tensile strength (30-40 MPa vs 20-37 MPa for HDPE) and higher stiffness. However, HDPE has better impact resistance at low temperatures and better ESCR. “Stronger” depends on which failure mode matters for your application.
2. Can PP replace HDPE?
In many applications yes - they overlap significantly. PP cannot replace HDPE where extreme cold (-40 degrees C) or high ESCR is required. HDPE cannot replace PP where temperatures exceed 80-82 degrees C continuously.
3. Which is more recyclable - PP or HDPE?
Both are recyclable. HDPE (code 2) currently has more established recycling infrastructure in most markets. PP (code 5) recycling is growing rapidly. For large industrial items like pallets and crates, both are routinely recycled by specialist processors.
Contact ICD Vietnam - PP and HDPE pallets, crates, and industrial packaging
Hotline 24/7: 0983 797 186 | 090 345 9186 | 090 5859 186
Zalo: icdvietnam | Email: sales@icdvietnam.com.vn
References
- Wikipedia: Polypropylene
- Wikipedia: High-density polyethylene
- ICD Vietnam technical team - material selection data from 200+ industrial deployments, 2014-2026
PP vs HDPE: Decision Guide for Procurement Teams
Procurement teams often ask which resin to specify when sourcing plastic pallets or industrial containers. The answer depends on four operational criteria - weight sensitivity, temperature exposure, cold-environment impact, and chemical contact. PP and HDPE overlap on price and food safety, but diverge significantly on the properties that matter most in warehouse and logistics settings.
| Criteria | PP Wins | HDPE Wins | Typical ICD Product |
|---|---|---|---|
| Weight sensitivity | Yes - density 0.90 g/cm3, lightest structural plastic | No - density 0.95 g/cm3, heavier per unit | PP pallet - medium-duty, light-to-medium loads |
| Temperature resistance | Yes - continuous use to 165 degrees C | Moderate - safe to 120 degrees C continuous | PP pallet - autoclave or high-heat environments |
| Impact in cold | No - becomes brittle below 0 degrees C | Yes - retains toughness in cold chain and freezer | HDPE pallet - cold storage, refrigerated transport |
| Chemical contact | Yes - excellent resistance to acids, alkalis, solvents | Good, but narrower chemical range than PP | PP pallet - chemical plants, fertiliser, food processing |
For most general warehouse and export applications operating above 0 degrees C, PP pallets offer the better weight-to-strength ratio and lower unit weight per trip. HDPE pallets are the correct choice when loads must survive freezer corridors or repeated high-impact drops.
ICD Vietnam supplies both resin types across its plastic pallet range - contact the team at 0983 797 186 to match the right specification to your application.
Reference
Material property comparison between PP and HDPE plastic - Society of Plastics Engineers (SPE).
