PS-Chi Mei PH-88S
PS-Chi Mei PH-88S (POLYREX® PH-88S) is a premium extrusion-grade high-impact polystyrene (HIPS) manufactured by Chi Mei Corporation, specifically optimized for sheet extrusion, thermoforming, and specialized molding of high-toughness containers. Featuring a low melt flow index of 2.6 g/10 min and a flexural modulus of 1,400 MPa, this grade is the industry standard for environmental stress-crack resistant (ESCR) refrigerator liners and disposable food packaging. Jucheng Precision, under ISO 9001 and IATF 16949 quality frameworks, specializes in molding PH-88S to secure uniform wall thickness. Utilizing our 25+ in-house five-axis CNC machines, we engineer robust, balanced tooling to handle its melt orientation and 0.4%-0.7% shrinkage.
POLYREX PH-88S Extrusion & Impact Properties
POLYREX® PH-88S is a high-performance extrusion-grade HIPS resin engineered by Chi Mei Corporation, designed to deliver high melt strength, heat resistance, and structural durability:
| Material Attribute | POLYREX PH-88S Nominal Value | Molding & Sheet Processing Advantage |
|---|---|---|
| Melt Strength | MFR 2.6 g/10 min (200°C x 5kg) | Low melt index delivers outstanding melt strength, preventing sheet sagging or tearing during progressive deep-draw thermoforming processes. |
| Impact Performance | Notched Izod 13 kJ/m² | Features high rubber-modified impact toughness, ensuring complete dynamic load resistance even in low-temperature refrigeration environments. |
| Thermal Softening | Vicat Softening Temperature 100°C | High-heat formulation resists sagging and thermal deformation, making it highly compatible with hot food-contact packaging. |
Specialized Process Adaptability for POLYREX PH-88S
With low melt fluidity and high structural elasticity, POLYREX PH-88S is highly optimized for robust packaging extrusion and specialized molding:
| Processing Method | Molding Compatibility & Process Setup Details |
|---|---|
| Sheet Extrusion & Thermoforming | Excellent. The primary process for PH-88S. Provides highly consistent, crack-free sheet extrusion for vacuum-formed refrigerator inner liners. |
| Extrusion-Compression Molding | Excellent. Ideal for dynamic, heavy-duty industrial containers, structural plastic trays, and disposable food cups. |
| Blow Molding | Good. Its high melt strength prevents parison sagging, supporting uniform wall thickness distribution in large hollow containers. |
PS-Chi Mei POLYREX PH-88S Tooling & Orientation Management Guide
Because POLYREX PH-88S is an extrusion-grade resin with high melt viscosity, managing material orientation and thermal shrinkage is critical during fabrication:
- Managing High Viscosity Flow: With an MFR of 2.6, this grade is viscous. Standard molding runners and gates must be designed with generous, rounded geometries to minimize shear stress and avoid premature material freeze-off.
- Optimizing Melt Orientation: High melt viscosity can cause high orientation stress along the flow path, leading to directional weakness. Jucheng’s tooling division uses 5-axis CNC machines to cut balanced core inserts, optimizing material delivery.
- Melt & Die Temperature Controls: Processing melt temperatures are kept between 190°C and 230°C (374°F to 446°F). Die and mold temperatures are managed tightly at 40°C to 60°C (104°F–140°F) using pressurized oil controllers to prevent rapid surface cooling and secure structural toughness.
- Low & Predictable Shrinkage: Like standard HIPS, PH-88S features a low, uniform shrinkage rate of 0.4% to 0.7%, allowing us to machine precise, tight-tolerance core cavities to secure exact end-part geometry.
Key Application Fields for PS-Chi Mei POLYREX PH-88S
- Appliance & Refrigerator Components: Deep-draw thermoformed refrigerator door liners, freezer drawers, structural inner panels, and dynamic tray accessories.
- Disposable Food Packaging: High-impact thermoformed yogurt cups, disposable drinking cups, food storage containers, and low-temperature storage trays.
- Industrial & Structural Sheets: Extruded high-impact plastic plates, protective structural covers, heavy-duty logistics bins, and dynamic separation boards.
Properties
| Density | 1.05 g/cm³ |
| Melt Mass-Flow Rate (MFR) (200°C/5.0kg) | 2.6 g/10 min |
| Tensile Strength at Yield | 28.0 MPa |
| Tensile Strength at Break | 24.0 MPa |
| Tensile Elongation at Break | 55 % |
| Flexural Strength | 34.0 MPa |
| Flexural Modulus | 1,400 MPa |
| Izod Impact Strength (Notched, 23°C) | 13 kJ/m² |
| Izod Impact Strength (Notched, -30°C) | 8.0 kJ/m² |
| Vicat Softening Point | 100 °C |
| Linear Mold Shrinkage | 0.40 - 0.70 % |
| Flammability Rating | UL 94 HB - |
| Maximum Part Size | 1000 x 800 mm |
| Minimum Part Size | 1 x 1 mm |