Table of Contents
Reviewed and updated by ICD - Week 37/2026
PP plastic number 5 (resin code 5) is Polypropylene - one of the safest, most widely used thermoplastics in food packaging, medical devices, and industrial applications worldwide.
What does plastic number 5 mean?
The number 5 stamped on plastic products (inside the recycling arrows symbol) is the Resin Identification Code (RIC) assigned by ASTM International. Each number identifies the polymer type:
| Code | Polymer | Common uses |
|---|---|---|
| 1 | PET | Water bottles, food containers |
| 2 | HDPE | Milk jugs, cleaning product bottles |
| 3 | PVC | Pipes, window frames |
| 4 | LDPE | Plastic bags, film wrap |
| 5 | PP (Polypropylene) | Food containers, medical, pallets |
| 6 | PS | Disposable cups, foam packaging |
| 7 | Other | Mixed/multi-layer plastics, PC, ABS |
Is PP plastic number 5 safe?
PP (resin code 5) is widely considered one of the safest plastics for food contact and everyday use. Key safety facts:
- No BPA: PP does not contain Bisphenol A (BPA) - a plasticizer found in polycarbonate (code 7) that has raised health concerns. PP is BPA-free by nature.
- Low leaching: PP has very low migration of chemical compounds into food or beverages under normal use conditions.
- High-temperature stability: PP remains stable up to 82-100 degrees C continuously, making it safe for microwave food containers (when rated) and hot dishwasher cycles.
- FDA and EU food contact approved: Virgin PP grades are approved for direct food contact under FDA 21 CFR and EU Regulation 10/2011.
Important caveat: Safety depends on using products as intended. Avoid using PP containers for alcohol-based liquids (some grades can leach additives), and do not reuse single-use PP containers beyond their design life.
Properties of PP (number 5) plastic
| Property | Value |
|---|---|
| Density | 0.89-0.91 g/cm3 |
| Melting point (Tm) | 160-168 degrees C (homopolymer) |
| HDT (heat deflection temperature) | 100-115 degrees C |
| Continuous service limit | Up to 82 degrees C |
| Chemical resistance | Excellent - acids, alkalis, solvents |
| Tensile strength | 30-40 MPa |
| Food contact approved | Yes (FDA 21 CFR, EU 10/2011) |
| Recyclability | Yes (code 5 - growing infrastructure) |
PP number 5 applications
- Food packaging: Microwave-safe containers, yogurt cups, deli containers, bottle caps
- Medical: Syringes, IV bags, autoclave-safe instrument trays
- Industrial: Plastic pallets, crates, bins, returnable packaging
- Consumer goods: Storage boxes, furniture, reusable cups
- Automotive: Bumpers, dashboards, under-hood components
Is plastic number 5 recyclable?
Yes - PP (code 5) is recyclable. The recycling infrastructure for PP has historically been less developed than PET (code 1) or HDPE (code 2), but has grown significantly in recent years. In Vietnam, PP is increasingly collected and recycled by industrial recyclers, particularly thick-wall PP items like pallets, crates, and automotive parts. Thin-film PP (yogurt lids, etc.) is harder to recycle through curbside programs.
For industrial PP products like pallets, end-of-life recycling is straightforward - old PP pallets are ground and reprocessed into lower-grade products such as drainage pipes, automotive components, or recycled content pallets.
PP number 5 vs other safe plastics
| Plastic | Code | BPA free | Food safe | Microwave safe |
|---|---|---|---|---|
| PP (Polypropylene) | 5 | Yes | Yes | Yes (when rated) |
| HDPE | 2 | Yes | Yes | Generally not |
| LDPE | 4 | Yes | Yes | No |
| PET | 1 | Yes | Yes | No |
| PVC | 3 | Varies | Limited | No |
| PS | 6 | Yes | Limited | No |
| PC (code 7) | 7 | No - contains BPA | Phasing out | Avoid |
Frequently Asked Questions
1. What does the number 5 on plastic mean?
The number 5 is the Resin Identification Code for Polypropylene (PP). It identifies the polymer type to facilitate sorting for recycling. PP is one of the safest plastics for food contact and is approved by FDA and EU food safety authorities.
2. Can I put number 5 plastic in the microwave?
PP (code 5) is the most commonly used plastic for microwave-safe food containers. However, check that the specific product is labeled “microwave safe” - not all PP items are designed for microwave use, especially thin-wall or decorative items.
3. Is PP number 5 better than PET number 1?
Both are safe for food contact. PP has better heat resistance (up to 100+ degrees C) and is the preferred choice when microwave use or high-temperature filling is required. PET has better optical clarity and is preferred for cold beverage bottles.
Contact ICD Vietnam - PP plastic pallets and packaging
Hotline 24/7: 0983 797 186 | 090 345 9186 | 090 5859 186
Zalo: icdvietnam | Email: sales@icdvietnam.com.vn
References
- ASTM D7611 - Standard Practice for Coding Plastic Manufactured Articles for Resin Identification
- FDA 21 CFR 177.1520 - Olefin polymers (PP food contact regulations)
- EU Regulation 10/2011 - Plastic materials and articles intended to contact food
PP Plastic Pros and Cons: Industrial Buyer’s Summary
For procurement and warehouse teams comparing plastic materials, the decision often comes down to a straightforward trade-off between heat tolerance and low-temperature flexibility. PP (polypropylene, resin code 5) stands out as the lightest common plastic at a density of 0.90-0.91 g/cm3 and withstands continuous use up to 130-171 degrees C, but it becomes brittle below 0 degrees C and degrades under prolonged UV exposure without additives. The table below covers the most-asked advantages and disadvantages side by side.
| Advantages | Disadvantages |
|---|---|
| Lightest common plastic: 0.90-0.91 g/cm3 - lowers transport weight per unit | Brittle below 0 degrees C - not suitable for frozen storage without cold-grade grades |
| Heat resistant to 130-171 degrees C - survives autoclave sterilisation and hot-fill lines | UV degradation - outdoor use requires UV-stabiliser additives, raising cost |
| Excellent chemical resistance - withstands acids, alkalis and most industrial solvents | Lower clarity than PET - semi-opaque appearance limits see-through packaging applications |
| BPA-free by chemistry - no bisphenol A in the polymer structure | Higher thermal expansion than metals - dimensional changes under temperature swings in precision applications |
| Recyclable (code 5) and increasingly accepted at kerb-side and industrial collection points | Harder to bond with adhesives than ABS or PET - requires flame or plasma pre-treatment for reliable joints |
In industrial material handling, PP’s strength-to-weight ratio and chemical resistance make it the standard resin for reusable containers and PP and HDPE plastic pallets used in warehouse racking and export logistics. PP crates and industrial plastic crates can also tolerate washdown with cleaning agents that would degrade PET or HIPS alternatives. Where cold-chain storage is involved, buyers should specify cold-grade PP or switch to HDPE, which retains impact resistance down to -40 degrees C.
Reference
Safety of plastic resin code 5 (Polypropylene) - British Plastics Federation (BPF).
