PP vs. PE vs. PET: Key Differences, Melting Points, and Best Applications for Plastic Bottles & Containers

Choosing the right plastic material for your product packaging is not just about cost – it directly impacts product safety, shelf life, compliance with international regulations, and even recyclability. For businesses sourcing plastic bottles, jars, or caps, understanding the differences between PP, PE (HDPE & LDPE), and PET is essential.

Below we break down the four most common plastic materials used in rigid packaging, including their identification codes, physical properties, melting points, suitable contents, and storage conditions.

1. PP (Polypropylene) – The Heat-Resistant Champion
Recycling Code: ♻️ 5

Melting Point: 160 – 170°C

Softening Point: 100 – 130°C

Density: 0.89 – 0.92 g/cm³ (floats on water)

Appearance & Feel: Translucent to opaque, waxy surface, rigid but not brittle.

Best For:

Microwaveable containers

Baby bottles and drinking cups

Yogurt cups, syrup bottles, medicine bottles

Hot-fill applications (up to 100°C)

Key Advantages: Excellent heat resistance, chemical inertness (no plasticizers needed), safe for food contact.

Limitations: Prolonged UV exposure causes degradation.

Storage Conditions: Store indoors, away from direct sunlight and high-temperature sources.

✅ Ideal for: Hot liquids, microwave use, and products requiring sterilization.

2. HDPE (High-Density Polyethylene) – The Strong & Rigid Workhorse
Recycling Code: ♻️ 2

Melting Point: 120 – 135°C

Density: 0.94 – 0.96 g/cm³

Appearance & Feel: Hard, tough, good impact strength, usually opaque.

Best For:

Detergent bottles, shampoo bottles

Milk jugs, juice containers

Industrial chemical containers

Large water storage tanks

Key Advantages: High strength-to-density ratio, excellent chemical resistance (acids, alkalis, salts).

Limitations: Not recommended for repeated hot-fill above 100°C; may leach over long-term use.

Storage Conditions: Dry, clean indoor environment, keep away from heat sources (≥1m distance), protect from UV.

✅ Ideal for: Non-food liquids, cleaning products, bulk storage, and outdoor use (with UV stabilization).

3. LDPE (Low-Density Polyethylene) – The Flexible Film Expert
Recycling Code: ♻️ 4

Melting Point: 105 – 115°C

Softening Point: 120 – 125°C

Density: 0.91 – 0.93 g/cm³

Appearance & Feel: Very soft, flexible, translucent, can be easily squeezed.

Best For:

Squeezable bottles (e.g., honey, condiments)

Plastic wrap (cling film)

Food storage bags

Bottle caps and liners

Key Advantages: Excellent flexibility, good moisture barrier, low-cost.

Limitations: Poor heat resistance (do not microwave), softer surface prone to scratching.

Storage Conditions: Cool, dry, well-ventilated area; avoid direct sunlight and open flames.

✅ Ideal for: Squeeze applications, disposable films, and lids.

4. PET (Polyethylene Terephthalate) – The Clear & Lightweight Standard
Recycling Code: ♻️ 1

Melting Point: ~245°C

Density: ~1.4 g/cm³ (sinks in water)

Appearance & Feel: Crystal clear, hard, glass-like surface.

Best For:

Water bottles, carbonated soft drink bottles

Edible oil bottles

Cosmetic jars and containers

Polyester fibers

Key Advantages: High clarity, lightweight, excellent gas barrier (keeps CO₂ in and O₂ out).

Limitations: Poor heat resistance (deforms at ~70°C); cannot be reused repeatedly; not suitable for hot liquids or alcohol.

Storage Conditions: Store at room temperature, avoid heat above 50°C; do not refill with hot water.

⚠️ Important Safety Note: PET bottles are designed for single-use or limited reuse. Do not use them to store hot water, oil, or alcoholic beverages for extended periods.

What Should You Store in Each Material?
PP: Hot soup, microwave meals, yogurt, syrups, medical products.

HDPE: Shampoo, detergents, bleach, milk, juice, industrial chemicals.

LDPE: Honey, ketchup, mustard (squeezable), frozen food bags.

PET: Still/sparkling water, carbonated drinks, edible oils, cosmetics (non-hot fill).

Compliance & Safety Reminder for Exporters
When exporting plastic bottles to Europe, the US, or other regulated markets, always ensure:

Your material is food-grade (FDA or EU 10/2011 compliant).

Recycled content (e.g., rPET, rHDPE) meets local regulations (e.g., EU PPWR requirements effective August 12, 2026).

Labels and inks are free from restricted PFAS and heavy metals.

Containers are clearly marked with the correct recycling code.