Material focus
Polystyrene (GPPS) selection, applications, and sibling resin routing on this page.
Polystyrene (GPPS)
Polystyrene (GPPS) Injection Molding: Properties, Applications and Design Guide
General-purpose polystyrene (GPPS) is a low-cost, rigid amorphous resin for disposable and light-duty cosmetic parts.
Polystyrene (GPPS)
When to specify Polystyrene (GPPS)
How procurement and design teams use Polystyrene (GPPS) on injection molded programs.
General-purpose polystyrene (GPPS) is a low-cost, rigid amorphous resin for disposable and light-duty cosmetic parts. It molds with crisp detail but is brittle compared with HIPS or ABS, so impact loads usually push buyers to those siblings. Use GPPS when clarity, cost, and stiffness matter more than drop performance. At NetProto, programs run from first-article validation through production on one hardened steel tool with no minimum order quantity. Upload CAD on the instant quote platform for DFM feedback before tooling release.
Key traits
Why buyers specify Polystyrene (GPPS)
Engineering and sourcing highlights. No NetProto processing numbers on this page.
Sourcing
Grade and compliance context travels with CAD on the instant quote platform.
Program fit
First articles through production on one steel tool, no MOQ.
NetProto platform
Instant CAD quoting and DFM feedback before tooling release.
Tooling lead time
Hardened steel tool build in about 10 business days on qualified programs (part complexity dependent).
Common grades
Common Polystyrene (GPPS) grades by use case
Pick one of these on the instant quote, or name any other commercial grade in the RFQ notes.
| Use case | Example grade | Typical parts |
|---|---|---|
| General purpose GPPS | Chimei POLYREX PG-33 | Lamp shades, transparent containers, cassette parts |
| Food container GPPS | Chimei POLYREX PG-383 | Disposable tableware, food containers, toys |
| High impact (HIPS class) | Kumho HI425 | Office equipment, appliances, toys, kitchen utensils |
Applications
Where this resin shows up on BOMs
Typical molded parts and what to specify on the purchase order.
| Application | Why this resin | Specify on the PO |
|---|---|---|
| Disposable cups and trays | Low cost, easy fill in thin sections | GPPS grade, food-contact documentation if required |
| Cosmetic packaging | High gloss potential with careful gate design | Cosmetic surface class (SPI) with resin |
| Light-duty housings (indoor) | Stiffness without engineering resin pricing | Impact requirement: if moderate, consider HIPS instead |
| Toys and novelties | Bright colors and crisp molded detail. Confirm food-contact needs on the supplier TDS when the part touches food. | GPPS grade and the food-contact callout, if the part needs it. |
Routing
GPPS, HIPS, or ABS
Polystyrene comes in two main forms. Choose by clarity and impact.
| Form | Best for | Not for |
|---|---|---|
| GPPS (general purpose) | Clear, rigid, low-cost parts | Drop or impact loads |
| HIPS (high impact) | Opaque trays, covers, liners | Clear parts or high heat |
| ABS | Tougher housings with better finish | Lowest-cost disposable parts |
RFQ
Ready to quote? Have this information ready
Prepare these details, then upload CAD on the instant quote platform.
Clarity requirement (clear GPPS vs opaque HIPS)
Impact level the part must survive
Food-contact documentation if required (supplier documentation)
Environmental stress crack exposure (oils, cleaners, fats)
Cosmetic class and gloss on visible surfaces
Commercial grade, or the use case to match (GPPS vs HIPS routing, food contact listed, high impact upgrade)
Expected annual volume (helps cavity and tool planning)
Next step
Upload CAD for an instant quote
Grade not finalized? Note Polystyrene (GPPS) on the RFQ and attach environment notes.
Compare and explore
Related guides
Pairwise comparisons and sibling material pages.
HIPS
Rubber-modified impact polystyrene.
HIPS
ABS
Tougher styrenic for housings.
ABS
SAN
Clear styrenic with better chemical resistance.
SAN
Materials library
Browse all resin guides.
Materials library
Reading a material datasheet
What the TDS (Technical Data Sheet) values mean for a molded part.
Reading a material datasheet
Specify resin grade on an RFQ
How to write grade, color, and fillers so the quote matches the part.
Specify resin grade on an RFQFAQ
Polystyrene (GPPS) injection molding FAQ
GPPS vs HIPS?
HIPS adds rubber phase for impact. GPPS is clearer and cheaper but more brittle.
Can polystyrene hold threads?
Small molded threads are possible; heavy loads often need inserts or a tougher resin.
Is PS suitable for outdoor use?
Generally no unless stabilized and tested for your climate.
What is the minimum order quantity for molded parts at NetProto?
NetProto has no minimum order quantity on molded parts from your production tool. Upload CAD on the instant quote platform to scope tooling and part pricing for your volume.
How do I quote this resin without a final grade selected?
List the resin family on the RFQ, attach environment and compliance notes, and upload CAD. At NetProto, engineers use DFM review to narrow grades before tooling release.
Next step
Quote Polystyrene (GPPS) parts with your CAD
Upload geometry and list Polystyrene (GPPS) or the target grade on the instant quote platform.