Texin — PS material injection molding products you can trust

If you need clear, dimensionally stable plastic parts, polystyrene is often the right choice — but only when molded to tight standards. At Texin we make PS material injection molding products every day, and we know what matters to both buyers and makers: surface quality, repeatable shrinkage, thermal limits and avoiding stress-related cracking. Below is a straightforward, practical guide drawn from real production data (numbers we use on the shop floor), written from the perspective of people who actually run molds.

Quick snapshot of PS we work with

• Common grades we mold: GPPS (high transparency), HIPS (impact‑modified), EPS (foamed).
• Key numbers you’ll want to keep in mind: Tg ≈ 80–90°C (softening near 80°C); long‑term use typically under ~70°C; amorphous density ≈ 1.04–1.06 g/cm3; typical molded shrinkage ≈ 0.4–0.7%. Thermal decomposition generally >300°C.

Why these details matter for PS material injection molding products

• Appearance: GPPS can deliver very high light transmission (≈90%+), but surface finish is sensitive to mold temperature and fill speed.
• Strength vs. clarity: GPPS is stiff and clear but brittle; HIPS trades some clarity for much better impact resistance.
• Dimensional control: shrinkage around 0.4–0.7% means mold design and temperature control directly affect final tolerances.

Common buyer & producer questions — and straight answers

Q: Can I use PS parts with hot liquids or in hot environments?
A: Not recommended above ~70°C for long service. PS softens around 80°C (Tg ~80–90°C), so repeated exposure to higher temperatures risks distortion or loss of mechanical performance.

Q: My parts must be transparent and glossy — what processing steps help?
A: Fast, well‑controlled filling and a mold temperature in the 40–50°C range give you good surface gloss and minimize flow marks. We also run melt/barrel temperatures in the 180–215°C band (nozzle typically 10–20°C lower) and prefer higher injection speeds for clear parts.

Q: Do I need to dry PS pellets before molding?
A: PS absorbs very little moisture (≈0.01–0.03%). Normally no drying is needed. If pellets were stored poorly, dry at 70–80°C for 2–4 hours (some applications use 80°C for 2–3 hours) — but in most production runs we skip drying.

Q: How do I avoid warpage and stress cracking in PS parts?
A: PS develops residual stress if cooled too quickly. Remedies: moderate to higher mold/ melt temperatures, slower or controlled cooling, select higher‑flow grades or add flow aids, and design gates and wall thicknesses to reduce abrupt cooling differences. These steps substantially reduce internal stress and risk of cracking.

Q: What injection pressures and speeds should I expect?
A: Typical injection pressure range for PS material injection molding products is roughly 200–600 bar. We use higher speeds for thin, transparent parts to avoid premature solidification; geometry and gate design determine exact settings.

Q: How does PS stand up to chemicals and outdoor use?
A: PS resists water, salts and many dilute acids, but it is attacked or swollen by organic solvents (chloroform, dichloromethane, toluene, butyl acetate). Long outdoor exposure causes yellowing and embrittlement from UV/oxidation — choose stabilized grades or alternative polymers for long‑term outdoor use.

Q: I need higher impact resistance — is that possible with PS?
A: Yes. HIPS (rubber‑modified PS) gives significantly better impact strength at the cost of opacity. Texin supplies both GPPS and HIPS depending on whether clarity or toughness is primary.

Production notes we follow (so your parts come right first time)

• Melt/barrel: typically 180–215°C (observe 250°C ceiling for flame‑retardant grades).
• Nozzle: set 10–20°C lower than barrel peak.
• Mold temp: maintain ~40–50°C for GPPS; small adjustments for surface vs. cycle time tradeoffs.
• Injection pressure: 200–600 bar typical. Use higher pressure only where geometry demands.
• Drying: usually unnecessary (absorption 0.01–0.03%); if needed 70–80°C for 2–4 hours.
• Shrinkage planning: design for ~0.4–0.7% shrinkage; verify with first‑article runs.

A final word — why Texin Making high‑quality PS material injection molding products is more than running colors through a press. It’s mold design, thermal control, grade selection and tooling discipline combined. We pay attention to the numbers above because they predict performance: Tg, mold temperature, shrinkage %, and suitable melt windows. If your parts demand clarity, tight tolerances or a balance of toughness and finish, we’ll recommend the right PS grade (GPPS, HIPS, EPS) and nail the process parameters so production is predictable.

Want to talk specifics? Send us your part drawing, target tolerances and intended service conditions. Texin will run a feasibility check and give you practical recommendations for tooling and the PS material injection molding products that meet your needs.

● Many years of mold design, development and manufacturing experience

● Pursue excellence and cast high quality

● High quality, high efficiency and high precision

● Take the initiative to provide timely, fast and dynamic customer service