GPPS, or General Purpose Polystyrene, is a type of polystyrene plastic that is widely used in various applications due to its low cost, ease of processing, and good optical properties. It is a rigid, transparent thermoplastic material that is commonly used for packaging, disposable cutlery, and other consumer products.
GPPS GRADES
| GRADE | PRODUCER | MFR (gr/10 min) | VICAT SOFTENING POINT (°C) | DATASHEET |
|---|---|---|---|---|
| GPPS 1028 | MASHREGH ZAMIN | 2.4 | 102 | download |
| GPPS 1038 | MASHREGH ZAMIN | 3.1 | 101 | download |
| GPPS 1034 | MASHREGH ZAMIN | 3.1 | 90 | download |
| GPPS 1084 | MASHREGH ZAMIN | 8 | 91 | download |
| GPPS 1233 | MASHREGH ZAMIN | 23 | 85 | download |
| GPPS 1047 | MASHREGH ZAMIN | 4.2 | 100 | download |
| GPPS 1077 | MASHREGH ZAMIN | 7 | 100 | download |
| GPPS 1067 | MASHREGH ZAMIN | 5.5 | 100 | download |
| GPPS 1115 | MASHREGH ZAMIN | 11 | 91 | download |
| GPPS 1144 | MASHREGH ZAMIN | 14 | 92 | download |
| GPPS 1160 | TABRIZ | 2.5 | 105 | download |
| GPPS 1460 | TABRIZ | 6.5 | 103 | download |
| GPPS 1540 | TABRIZ | 11 | 91 | download |
| G 1161 | TAKHTE JAMSHID | 4 | 104 | download |
| G 1551 | TAKHTE JAMSHID | 9 | 98 | download |
| MP08 | MOHEB | 11 | 105 | download |
What is gpps ?
| Composition | Made from styrene monomers |
|---|---|
| Properties |
Clear, hard, and brittle; can be solid or foamed
|
|
Temperature behavior
|
Solid at room temperature, flows above 100°C (glass transition temperature)
|
|
Usage
|
Protective packaging, containers, cutlery, modeling, and more
|
|
Environmental impact
|
Not biodegradable; accumulates in environments, especially in waterways |
gpps General specifications
| GPPS Properties | |
|---|---|
| Property | Value |
| Density | 1.04 - 1.07 g/cm³ (grams per cubic centimeter) |
| Water Absorption | Low (0.03 - 0.1%) |
| Transparency | Transparent to translucent |
| Mechanical Properties | |
| Tensile Strength | 35 - 60 MPa (megapascals) |
| Elongation at Break | 1.5 - 4% |
| Flexural Strength | 70 - 100 MPa (megapascals) |
| Izod Impact Strength (Notched) | 1.5 - 3 J/m (joules per meter) |
| Rockwell Hardness | R85 - R115 |
| Thermal Properties | |
| Melting Point | 180-260°C (degrees Celsius) |
| Heat Deflection Temperature (HDT) | 75 - 95°C (degrees Celsius) |
| Coefficient of Linear Thermal Expansion | 6 - 8 × 10⁻⁵ K⁻¹ (per Kelvin) |
| Vicat Softening Temperature | 90 - 105°C (degrees Celsius) |
| Electrical Properties | |
| Dielectric Strength | 15 - 30 kV/mm (kilovolts per millimeter) |
| Surface Resistivity | 10¹⁴ - 10¹⁶ Ω/sq (ohm per square) |
| Volume Resistivity | 10¹⁵ - 10¹⁸ Ω·cm (ohm-centimeter) |
| Optical Properties | |
| Refractive Index | 1.59 - 1.60 |
| Light Transmission | 88 - 92% (for 3 mm thickness) |
| Chemical Properties | |
| Resistance | Resistant to acids, alkalis, and aqueous solutions Susceptible to organic solvents, oils, and fats |
| Processing Properties | |
| Processability | Good flow properties Suitable for injection molding, extrusion, and thermoforming |
It’s important to note that the specific values of these properties may vary depending on the grade, additives, and processing conditions of the GPPS material.
Key Properties of GPPS
- High transparency and clarity, making it suitable for applications requiring visibility
- Rigid and brittle with low-impact strength
- Excellent electrical insulation properties
- Lightweight and good dimensional stability
- Easy to process via injection molding, extrusion, and thermoforming
- Low cost compared to other plastics
GPPS Manufacturing Process
GPPS is produced through the polymerization of styrene monomers, typically using a suspension process. The resulting solid product is compressed into granules for further processing. It can be manufactured using various methods, including:
- Injection molding
- Extrusion
- Vacuum forming
- Thermoforming
The processing temperature range for GPPS is typically 190-230°C.
GPPS Common Applications
Packaging
- Food containers, trays, CD/DVD cases, disposable cups and plates
Household items
-
Picture frames, plastic cutlery, desk accessories.
Automotive
-
Interior trim pieces and dashboard panels
Consumer products
- Toys, cosmetic packs, costume jewelry
GPPS Advantages and Disadvantages
Advantages:
- Excellent transparency and aesthetics
- Cost-effective and easy to process
- Good electrical insulation and dimensional stability
Disadvantages:
- Brittle and low-impact strength
- Limited chemical resistance to certain solvents and oils
- Lower heat resistance compared to some other plastics
GPPS is a versatile and economical plastic widely used in various industries due to its transparency, processability, and cost-effectiveness, despite its limitations in impact strength and chemical resistance
Comparison to High Impact Polystyrene
While GPPS and HIPS share some similarities, they have distinct differences:
- GPPS is more transparent and has better clarity than HIPS
- HIPS has higher impact strength and better dimensional stability
- GPPS is more cost-effective than HIPS
- HIPS is naturally white with a matte finish, while GPPS is clear
GPPS is a versatile and economical plastic widely used in various industries due to its transparency, processability, and cost-effectiveness, despite its limitations in impact strength and chemical resistance
Conclusion
Polystyrene (General Purpose) GPPS is a rigid and transparent thermoplastic polymer that is highly versatile and easy to process. GPPS has excellent electrical insulation properties, is lightweight, and has good dimensional stability. It is commonly used in various applications such as packaging, household items, and office supplies.