Product Overview & Key Features
This product is manufactured by Formosa Plastics (Formosa), belonging to the TAIRIREX® series, and the material category is general-purpose polystyrene GPPS (General Purpose Polystyrene). GP535H is a high-flow transparent polystyrene resin, and the raw material is natural transparent pellets. This grade has a relatively high melt flow rate, featuring stable light transmittance, rigidity, and good dimensional stability, and is resistant to various non-polar chemicals at room temperature. The raw material is suitable for conventional thermoplastic molding processes, primarily using injection molding processing methods, which can meet the high-speed production demands of thin-walled parts. Core Features: High flow, high transparency, low internal stress tendency, excellent rigidity, and easy coloring.
Technical Specifications
Physical Properties
| Property | Test Value | Test Unit | Test Standard |
| Density (23 ℃) | 1.04 | g/cm³ | ASTM D792 / ISO 1183 |
| Melt Volume-Flow Rate (200 ℃, 5 kg) | 2.5 | g/10min | ASTM D1238 / ISO 1133 |
| Mold Shrinkage, Parallel (3.2 mm) | 0.40 – 0.70 | % | ASTM D955 |
Mechanical Properties
| Property | Test Value | Test Unit | Test Standard |
| Tensile Modulus (23 ℃) | 3250 | MPa | ASTM D638 / ISO 527-2 |
| Tensile Strength (23 ℃) | 49 | MPa | ASTM D638 / ISO 527-2 |
| Tensile Strain at Break (23 ℃) | 2.4 | % | ASTM D638 / ISO 527-2 |
| Flexural Modulus (23 ℃) | 2650 | MPa | ASTM D790 / ISO 178 |
| Flexural Strength (23 ℃) | 84 | MPa | ASTM D790 / ISO 178 |
| Charpy Unnotched Impact Strength (23 ℃) | 17 | J/m | ASTM D256 |
Thermal Properties
| Property | Test Value | Test Unit | Test Standard |
| Heat Deflection Temperature (1.8 MPa, Unannealed) | 88 | ℃ | ISO 75-2/A / ASTM D648 |
| Vicat Softening Temperature (B50 / 50 N) | 106 | ℃ | ISO 306 / ASTM D1525 |
| Flammability, All Colors (1.5 mm) | HB | — | UL 94 |
Other Properties
| Property | Test Value | Test Unit | Test Standard |
| Residual Monomer | <500 | ppm | — |
Disclaimer: The technical specifications for Formosa TAIRIREX® GP535H presented herein are derived from data issued by Formosa or certified third-party testing institutions. While we have made every effort to ensure the accuracy of the information provided, we assume no liability for any consequences arising from the use of TAIRIREX® GP535H based on these data. Given the variables involved in processing conditions, we strongly recommend conducting thorough trials of TAIRIREX® GP535H under your specific operational environment prior to final material selection.
Applications & Processing Guidelines
Applicable Application Scenarios
Daily-use transparent plastic products, disposable food containers, stationery products, transparent housings, lighting accessories, cosmetic inner packaging, thin-walled injection molded small parts, and transparent toy components.
Processing Guidelines
- Raw Material Drying: GPPS has low moisture absorption. Short-term storage in normal environments may not require drying; products with high appearance requirements are recommended to be dried at 70–80 ℃ for 2–3 hours to avoid silver streaks and bubble defects caused by moisture.
- Molding Temperature Range: Barrel temperature 190 ℃ ~ 230 ℃; mold temperature recommended at 40–60 ℃.
- This grade features excellent fluidity. When producing thin-walled products, injection pressure and injection speed can be appropriately reduced to minimize internal stress and lower the risk of subsequent cracking.
- Shutdown Cleaning: General-purpose GPPS raw material can be used to clean the barrel. Direct co-machine switching with PVC raw materials is not recommended.
Logistics, Packaging & Compliance
- Standard Packaging: 25 kg/bag, moisture-proof woven lined plastic bag packaging
- Hazard Classification: General non-hazardous chemical raw material, not classified as dangerous goods under the United Nations, supporting regular container load sharing (LCL) and full container load (FCL) sea and land transportation.
- Document Support: COA factory quality inspection report, TDS technical data sheet, and MSDS safety datasheet can be provided synchronously.
- Compliance Certifications: The product meets restricted substance requirements related to RoHS and REACH, and is suitable for shipment to European and American markets.
- Delivery Lead Time: Regular stock items can be arranged for short-term dispatch; futures orders are confirmed through negotiation based on Formosa’s production scheduling plan.
FAQs
Q1: TAIRIREX® GP535H GPPS is prone to silver streaks when producing transparent products. How can this be improved?
A: Silver streaks mostly originate from raw material moisture, poor venting, or internal stress. Batches with high appearance requirements are recommended to be dried in advance; optimize the mold venting structure; reasonably control the injection speed to avoid shear overheating.
Q2: How to select and distinguish between GP535H and the same series GP5250?
A: GP535H has higher fluidity and is preferentially used for thin-walled, high-speed injection molded products; GP5250 has medium fluidity and is suitable for thick-walled parts requiring higher impact resistance. Selection and sample testing can be conducted based on part wall thickness and production line efficiency.
Q3: Can GPPS GP535H directly contact food?
A: This grade possesses basic food contact qualification credentials. Specific compliance needs to be verified in combination with target regional market regulations (FDA/national standards). It is recommended to request the official food contact statement and complete terminal finished product compliance testing.
Q4: Can this raw material be blended and modified with HIPS?
A: GPPS and HIPS possess good compatibility and can be blended to adjust rigidity and toughness; the blending ratio and processing temperature need to be determined through sample testing to finalize product performance.
