In the bottled water industry, the choice of packaging materials directly affects the safety, cost-effectiveness and environmental performance of the product. Bottle-grade polyester chips are currently the mainstream material for bottled water packaging in the world, accounting for more than 80% of the market share. So why does the bottled water industry generally choose bottle-grade PET instead of other plastics (such as PP, HDPE, etc.) or glass?
Safety of polyester chips
Strict food-grade certification requirements to ensure drinking water safety
Bottled water is in direct contact with drinking water, so the packaging materials must comply with food contact material regulations such as FDA, EFSA, GB 4806.7, etc. Bottle-grade PET strictly controls the following indicators during the manufacturing process:
Low acetaldehyde content (< 1 ppm). Acetaldehyde affects the taste of water, and bottle-grade PET reduces its release by optimizing the polymerization process.
No plasticizer (such as BPA). Unlike PC plastics, PET does not contain bisphenol A and will not pollute the water quality.
The heavy metal content meets the standard (lead, cadmium, etc. < 0.1 ppm) to avoid the dissolution of harmful substances during long-term storage.
Long-term stability test
Bottle-grade PET needs to pass long-term immersion experiments to ensure that no harmful components are released during the shelf life. In contrast, some recycled plastics require additional processing to meet food-grade standards.
Physical properties of polyester chips
Lightweight (90% lighter than glass)
A 500ml PET bottle weighs only 10-15 grams, while a glass bottle usually weighs more than 200 grams.
Lightweight greatly reduces transportation costs and is particularly suitable for large-scale distribution.
High transparency (transmittance>90%)
The transparency of bottle-grade PET is close to that of glass, and consumers can directly see the water quality and enhance their purchasing confidence.
In contrast, HDPE is translucent and PP has low transparency.
Excellent mechanical strength
Drop resistance. PET bottles are not easy to break in a drop test from a height of 1.5 meters, while glass bottles are fragile.
Pressure resistance. Carbonated beverage bottles need to withstand 3-6 bar air pressure, and the polymer chain structure of bottle-grade PET can effectively resist expansion.
Production cost and processing efficiency advantages
Low raw material cost (compared to glass and metal)
The price of raw materials (PTA+MEG) for petroleum-based PET is stable, and the cost can be controlled after large-scale production.
The manufacturing energy consumption of glass bottles is high (requires a 1400℃ furnace), while the PET injection-blow molding process only requires 200-280℃.
High-speed production efficiency
Injection and blow molding are integrated. Modern production lines can produce 50,000 PET bottles per hour (such as Krones blow molding machines).
Glass bottles are slow to produce (about 2,000 per hour) and have high mold costs.
Design flexibility
PET bottles can quickly adjust their shapes through molds to meet brand differentiation needs.
Glass bottle modification requires re-molding, which has a long cycle and high cost.
Environmental protection and recyclability
High recycling rate
PET is one of the plastics with the most complete recycling system, and recycled PET (rPET) can be re-made into bottles or textile fibers.
The EU Single-Use Plastics Directive (SUP Directive, 2019/904) stipulates that “Member States shall ensure that PET bottles contain at least 25% recycled plastic by 2025 and 30% by 2030.”
Carbon footprint is lower than glass and aluminum cans
Research shows that the carbon emissions of a 500ml PET bottle are 82g CO₂, while that of a glass bottle is 345g CO₂.
Lightweighting further reduces carbon emissions in the transportation process.
Breakthrough in chemical recycling technology
Depolymerization technology can restore waste PET bottles to PTA and MEG monomers, achieving a “closed loop”.
Bio-based PET is partially made of sugarcane raw materials, reducing dependence on oil.
Commonly used water bottle grade polyester chips brands and models
| Brands | Models | Properties | Applications |
| Indorama Ventures | IV-84 | Viscosity: 0.84dl/g, low acetaldehyde (<0.5ppm) | carbonated beverages bottles |
| DAK Americas | Traytuf® 1006 | High transparency, light transmittance >91% | carbonated beverages bottles |
| Far Eastern | FENC® BG-802 | Rapid crystallization, suitable for high-speed bottle blowing | Drinking water bottles |
| Lotte | Lotte® BP-801 | Ultra-high IV value (0.86dl/g), strong pressure resistance | Drinking water bottles |
| Hengli | HL-801 | Low color difference, b value <1.5 | Drinking water bottles |
| Wankai | WK-801/WK-811 | Ultra-low acetaldehyde (<0.3ppm) | Drinking water bottles |
| JADE | CZ-302 | Low content of acetaldehyde | Drinking water bottles |
| China Resources | CR-8816 | / | Drinking water bottles |
| China Resources | CR-8828 | / | carbonated beverages bottles |