Polyethylene Terephthalate (PET) injection molding combines precision engineering with versatile material properties to create durable, lightweight plastic components.
Our team of experienced engineers specializes in PET injection molding for a wide range of applications. With state-of-the-art equipment and comprehensive material expertise, we deliver high-quality PET components that meet your exact specifications.
The most common form of polyethylene terephthalate used in injection molding. Features excellent clarity, good mechanical strength, and moderate chemical resistance. Ideal for general-purpose applications requiring transparency.
⚒ General PurposeGlycol-modified PET offering enhanced impact resistance, improved processability, and reduced crystallinity. PETG maintains excellent clarity while providing better toughness and easier processing than standard PET.
⚒ Enhanced ImpactPET formulations with glass fiber or other reinforcements for significantly improved mechanical properties. These grades offer higher strength, stiffness, and dimensional stability for engineering applications.
⚒ High PerformancePET (Polyethylene Terephthalate) is a versatile thermoplastic known for its strength, clarity, and chemical resistance. It comes mainly in amorphous PET (A-PET) for transparency and crystalline PET (C-PET) for heat resistance, making it ideal for packaging, containers, and industrial components.
Recycled polyethylene terephthalate offering sustainable manufacturing options
Modified PET with enhanced impact resistance for demanding applications
Formulated for enhanced thermal stability and mechanical properties
Specially formulated for food contact applications
Enhanced resistance to degradation from ultraviolet exposure
| Property | Value | Unit |
|---|---|---|
| Density | 1.38-1.41 | g/cm³ |
| Tensile Strength | 50-60 | MPa |
| Flexural Modulus | 2.5-3.0 | GPa |
| Elongation at Break | 120-200 | % |
| Heat Deflection Temperature | 70-80 | °C |
| Melting Point | 245-265 | °C |
| Mold Shrinkage | 0.2-0.6 | % |
Excellent clarity and transparency
High tensile strength (50-60 MPa)
Good chemical resistance to many solvents
Food-contact suitability confirmed for the exact grade and use
100% recyclable (resin identification code #1)
Excellent gas barrier properties
Good dimensional stability
Moisture sensitivity during processing
Requires thorough pre-drying (≤0.005% moisture) processing
Limited heat resistance (HDT ~70°C) processing
Susceptible to UV degradation without stabilizers processing
Moderate impact resistance (unmodified grades) processing
Crystallization can affect transparency processing
Higher processing temperatures than many plastics
PET injection molding requires specialized expertise to achieve optimal results. The process begins with properly dried PET resin that's precisely heated to its melting point before being injected into custom-designed molds under carefully controlled pressure and temperature conditions.
| Specification | Standard Tolerance | Precision Tolerance | Notes |
|---|---|---|---|
| Dimensional Accuracy | ±0.125 mm | ±0.05 mm | Dependent on part geometry and size |
| Wall Thickness | ±0.1 mm | ±0.05 mm | Minimum recommended: 0.5 mm |
| Draft Angle | 1° – 2° | 0.5° – 1° | Required for proper ejection |
| Surface Finish | SPI-C1 to D3 | SPI-A1 to B2 | Highly polishable for optical clarity |
| Gate Vestige | 0.05 – 0.1 mm | ≤0.025 mm | Hot runner systems minimize gate marks |
✅ Wall Thickness: Maintain uniform wall thickness (ideally 0.5-3.0 mm) to prevent warping and sink marks
✅ Draft Angles: Minimum 1° per side, preferably 1.5-2° for easier ejection
✅ Gate Design: Pin gates or hot runner systems preferred for cosmetic parts
✅ Radii and Fillets: Minimum 0.5 mm radius on all corners to reduce stress concentration
✅ Ribs and Bosses: Base thickness should be 60% of adjoining wall to prevent sink marks
✅ Texture: Allow additional draft for textured surfaces (1° per 0.025 mm depth)
✅ Drying Requirements: PET must be dried to moisture content below 0.005% (50 ppm) to prevent hydrolysis
✅ Drying Parameters: 4-6 hours at 160-180°C in a dehumidifying dryer
✅ Material Handling: Dried material should be processed within 1 hour or kept in sealed, dry containers
✅ Melt Temperature: 270-290°C (optimum around 280°C)
✅ Mold Temperature: 15-40°C for amorphous parts, 80-120°C for crystalline parts
✅ Injection Speed: Moderate to fast to prevent premature freezing
✅ Cooling Time: Sufficient to ensure dimensional stability (varies by wall thickness)
PET Injection Molding Applications
PET injection molding is widely used to produce strong, lightweight, and transparent parts. Common applications include packaging, medical, and precision components in consumer and industrial products.
Electronic device housings
Automotive interior components
Electrical insulators
Household appliance parts
Precision mechanical components
Laboratory equipment and test tubes
Medical device components
Pharmaceutical containers
Diagnostic equipment housings
Sterilizable medical tools
Beverage bottles and containers
Food packaging and trays
Cosmetic and personal care containers
Pharmaceutical packaging
Clamshell containers
Selected PET grades have documentation supporting specified food-contact uses. It's widely used for food and beverage packaging due to its excellent clarity, barrier properties, and safety profile. For food applications, virgin or food-grade recycled PET (rPET) should be used with appropriate processing conditions to maintain compliance with regulatory requirements.
The main differences are in processing and mechanical properties. PETG (glycol-modified PET) offers easier processing with less crystallization, better impact resistance, and improved clarity. Standard PET has higher temperature resistance, better chemical resistance, and greater stiffness. PETG is preferred for applications requiring high clarity and toughness, while standard PET is better for applications requiring thermal stability.
Moisture is critical in PET processing. Even small amounts (>0.005%) can cause hydrolytic degradation during melting, resulting in reduced molecular weight, decreased mechanical properties, and visual defects like streaks and bubbles. Proper drying (4-6 hours at 160-180°C) in a dehumidifying dryer is essential before processing PET to achieve optimal results.
PET offers several environmental advantages. It's 100% recyclable (resin identification code #1) and widely accepted in recycling programs globally. It has a lower carbon footprint compared to glass or metal alternatives due to its lightweight nature, reducing transportation emissions. Additionally, recycled PET (rPET) can be used in many applications, creating a circular economy opportunity while maintaining material properties.
PET can achieve a wide range of surface finishes, from high-gloss to matte textures. It's highly polishable, allowing for optical-quality surfaces (SPI-A1) when required. Textured surfaces can be created through mold texturing techniques. For transparent applications, proper mold temperature control and processing parameters are essential to prevent crystallization that could affect clarity.
Our technical team is ready to discuss your PET injection molding requirements.
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