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Styrenic Resin · CAS 9003-53-6

Polystyrene

(–CH2–CH(C6H5)–)n Molar mass Polymer; molecular weight distribution, not a single value

The polystyrene resin supplied by Chelora Chemicals — a clear, rigid or impact-modified styrenic resin used across packaging, disposables and insulation — exported from Indonesia as virgin pellet with full batch documentation on every shipment.

Identification Sheet REP.
Product typeAmorphous styrenic homopolymer resin (general purpose & high-impact grades)
CAS number9003-53-6
Repeat unit(–CH₂–CH(C₆H₅)–)ₙ
Density Range1.04 – 1.06 g/cm³
AppearanceClear (GPPS) or opaque white (HIPS) pellet
Common synonymsPS, GPPS, HIPS, Polystyrene Resin
Density1.04 – 1.06 g/cm³ASTM D792
Glass Transition / Softening Point95 – 105 °Camorphous, Vicat softening
Melt Flow Rate1.5 – 20 g/10 mingrade dependent, 200 °C/5 kg
Tensile Strength35 – 50 MPa (GPPS) · 20 – 30 MPa (HIPS)grade dependent
AppearanceClear pellet (GPPS); opaque white pellet (HIPS)2–4 mm nominal
Grades OfferedGeneral-purpose (GPPS), high-impact (HIPS)by rubber content
01 / PRODUCT DOSSIER

What Polystyrene is, and why buyers source it

A working overview of the resin's amorphous structure, how rubber modification changes its performance, and the grades Chelora Chemicals keeps in regular supply.

Polystyrene is an amorphous thermoplastic built from the styrene monomer, whose bulky aromatic ring prevents the chain from folding into any ordered crystalline structure at all — unlike the semi-crystalline polyolefins, polystyrene is entirely amorphous, which is the direct source of its glass-like optical clarity in general-purpose grade and its characteristically brittle fracture behaviour.

At room temperature general-purpose polystyrene (GPPS) is supplied as a clear, water-white pellet, while high-impact polystyrene (HIPS) — which incorporates a dispersed rubber phase, typically polybutadiene, to blunt crack propagation — is supplied as an opaque white pellet. Both process easily on standard injection-moulding, extrusion sheet and foam-extrusion equipment.

Where it fits in the value chain

GPPS's clarity and rigidity make it the preferred resin for clear disposable cups, cutlery, CD/DVD cases and point-of-sale display packaging, and it is also expanded with a blowing agent into expanded or extruded polystyrene foam for food packaging and building insulation. HIPS trades some of that clarity and rigidity for substantially better impact resistance, making it the preferred resin for appliance housings, toys, and disposable food-service items such as yoghurt cups and cutlery where some impact resistance is wanted without the cost of an engineering resin.

Grades we supply

Chelora Chemicals offers Polystyrene in general-purpose (GPPS) and high-impact (HIPS, in a range of rubber contents) grades across standard melt-flow-rate ranges for injection moulding, sheet extrusion and foam applications. Each grade is supplied with a batch-wise certificate of analysis covering melt flow rate, density and, for HIPS, rubber content.

02 / MANUFACTURING ROUTE

How Polystyrene is produced

An overview of the production route for orientation purposes. Our manufacturing partners' own process parameters and in-process controls are proprietary and are not disclosed beyond what is needed to interpret the certificate of analysis.

Polystyrene is produced by free-radical polymerisation of styrene monomer, typically in a continuous bulk or solution process using a thermal or peroxide initiator, with unreacted monomer stripped and recycled at the end of the reactor train. Styrene itself, the building-block monomer, is manufactured by catalytic dehydrogenation of ethylbenzene, which is produced by Friedel-Crafts alkylation of benzene with ethylene — tying polystyrene's feedstock chain back to the same aromatic and olefin building blocks used across the wider petrochemical industry.

High-impact polystyrene is made by dissolving polybutadiene rubber in the styrene monomer feed before polymerisation begins: as the styrene polymerises, the rubber phase separates out into finely dispersed droplets grafted at their surface to the growing polystyrene matrix, a morphology engineered during polymerisation itself (rather than by later mechanical blending) to give the dispersed rubber particles that blunt crack propagation and give HIPS its impact resistance.

03 / APPLICATIONS

Industries and processes that use it

Polystyrene is consumed across food-service disposables, rigid packaging, appliance housings and insulation foam. The fields below account for most of the demand we see through our export desk.

Field 01

Food-Service Disposables

Injection-moulded or thermoformed into clear cups, cutlery and lids (GPPS) and impact-resistant cups, trays and cutlery (HIPS).

Field 02

Rigid Packaging & Display

Extruded into sheet for thermoformed clamshell packaging, and injection-moulded into CD/DVD cases and point-of-sale display fixtures.

Field 03

Appliance Housings & Toys

HIPS injection-moulded into appliance housings, electronics casings and toys, where impact resistance is needed without the cost of an engineering resin.

Field 04

Foam Insulation & Food Packaging

Expanded with a blowing agent into EPS/XPS foam for building insulation board, and foamed food trays and protective packaging.

04 / REACTION CHEMISTRY

How the resin is typically converted forward

The amorphous structure, and the presence or absence of a rubber phase, governs almost all of Polystyrene's further processing behaviour. The categories below account for most of the ways it is converted into a finished part.

Injection Moulding

Melted and injected into a mould cavity under pressure to form clear (GPPS) or impact-resistant (HIPS) parts such as cups, cutlery and housings.

Sheet Extrusion & Thermoforming

Extruded into flat sheet, then reheated and vacuum- or pressure-formed over a mould to produce clamshells, trays and cups.

Foam Extrusion / Expansion

Combined with a physical or chemical blowing agent and expanded, either by pre-expanding beads (EPS) or direct foam extrusion (XPS), to form low-density insulation and packaging foam.

Rubber-Phase Grafting (HIPS Manufacture)

Polybutadiene rubber dissolved in the styrene feed separates into dispersed, matrix-grafted particles as polymerisation proceeds, engineering the impact-resistant morphology directly into the resin.

05 / RELATED BUILDING BLOCKS

Polystyrene against related feedstock and polyolefin products we supply

Buyers sourcing polystyrene resin often also need the aromatic and olefin feedstocks its monomer is built from, or a related commodity resin. A quick reference to what else is on our regular supply list.

ProductCAS NumberCategoryNotes
Polystyrene9003-53-6Amorphous styrenic resinThe product on this page — a clear or impact-modified resin for packaging and disposables.
Benzene71-43-2Aromatic hydrocarbonThe aromatic feedstock alkylated with ethylene to make ethylbenzene, the precursor to styrene monomer — see its product page.
Ethylene74-85-1Olefin monomerThe olefin feedstock alkylated with benzene to make ethylbenzene, the precursor to styrene monomer — see its product page.
Polypropylene9003-07-0Stereoregular polyolefinA related commodity resin used in overlapping rigid-packaging applications — see its product page.

Exact physical constants and processing specifications are confirmed per batch on the certificate of analysis — treat the notes above as a sourcing guide, not a specification sheet, for products other than Polystyrene.

06 / HAZARD & HANDLING

Safety classification at a glance

Based on GHS classification as commonly listed for this substance. This is a summary for orientation only — always work from the current safety data sheet supplied with your specific batch.

Low Hazard Profile

Not classified as hazardous under GHS in solid pellet form.

Combustible Solid

Combustible; pellets and especially fine dust can support combustion once ignited, and foam grades burn readily if not treated with a flame retardant.

Dust Control

Minimise accumulation of polymer dust/fines, which present a greater ignition risk than pellets.

Molten Handling

Processing equipment handles the resin molten; standard hot-surface and fume-extraction precautions apply at the extruder.

PPE Standard

Standard gloves and eye protection are sufficient for routine handling of pellets.

Residual Monomer

Residual styrene monomer is controlled to a low level and checked against food-contact limits where relevant.

Signal word

Not classified; refer to the batch MSDS for grade-specific guidance.

This product has a low hazard profile in its solid pellet form and is not classified as hazardous under GHS. The principal handling precautions concern combustible-dust accumulation from fines generated during conveying and bagging, standard hot-surface precautions during melt processing, and, where foam-grade resin is converted on site, the flammability of unretarded foam. Full first-aid, storage, spill and PPE guidance is in the MSDS issued with every shipment, and should be read in full before this material is handled.

07 / STORAGE & SHELF LIFE

Keeping it on spec between delivery and use

General storage guidance for this grade. Site-specific storage rules, segregation requirements and re-test intervals should follow your own EHS procedures and the MSDS issued with your batch.

Storage TemperatureAmbient, dry, indoor
Container25 kg bags / 1,000 kg jumbo bags
Typical Shelf Life24 months, unopened
Keep Away FromUV exposure, moisture, heat sources
Beyond Shelf LifeRe-check melt flow rate before processing

Store in a dry, ambient-temperature warehouse, out of direct sunlight and away from heat sources, since prolonged UV and heat exposure can discolour the resin and degrade its processing behaviour. Keep bags sealed to prevent moisture pickup and contamination with other resin grades. Re-check melt flow rate and residual monomer content on material held past its retest date before processing.

08 / PACKING & EXPORT

How it ships from Indonesia

Standard packing and export terms for this product. Confirm exact figures against your order — they vary slightly by destination and quantity.

Standard Packing25 kg bags on pallet
Bulk Packing1,000 kg jumbo bags / bulk hopper truck
Min. OrderFrom 1 tonne
Lead Time2 – 3 weeks
Export TermsFOB · CFR · CIF
09 / QUALITY & DOCUMENTATION

What travels with every batch

Specification is agreed before the purchase order, not discovered on arrival. Every shipment of Polystyrene leaves with a documented, checkable paper trail.

Doc 01

Certificate of Analysis

Batch-wise assay, colour and key physical constants, issued against the agreed specification so your QC team can check it, not just file it.

Doc 02

Safety Data Sheet

GHS-format SDS in English covering hazard classification, handling, storage, first-aid and spill response for the exact grade shipped.

Doc 03

Technical Data Sheet

Reference physical and chemical properties, recommended storage and typical applications, for internal circulation to your process or R&D teams.

Doc 04

Certificate of Origin

Confirms Indonesian origin for customs clearance and any preferential-duty claim at your destination port.

Doc 05

Dangerous Goods Declaration

UN packing group, classification and shipper's declaration prepared ahead of loading so documentation never holds up customs.

Doc 06

Third-Party Inspection

Independent pre-shipment inspection and re-sampling can be arranged on request, at your cost, for buyers who require it as a matter of policy.

10 / FAQ

Frequently asked questions

What buyers most often ask our sales desk about this grade.

01What is Polystyrene used for?+
Across food-service disposables (cups, cutlery, lids, trays), rigid packaging and display (thermoformed clamshells, CD/DVD cases), appliance housings and toys (HIPS), and foam insulation and food packaging (EPS/XPS).
02What is the difference between GPPS and HIPS?+
General-purpose polystyrene (GPPS) is a clear, rigid, unmodified homopolymer with higher stiffness but brittle fracture behaviour; high-impact polystyrene (HIPS) incorporates a finely dispersed polybutadiene rubber phase, grafted in during polymerisation, which substantially improves impact resistance at some cost to clarity and stiffness.
03How is Polystyrene produced?+
By free-radical polymerisation of styrene monomer (itself made by dehydrogenating ethylbenzene, produced from benzene and ethylene), in a continuous bulk or solution process; HIPS is made by dissolving polybutadiene rubber in the styrene feed before polymerisation so the rubber phase separates out and grafts to the matrix as the reaction proceeds.
04What grades does Chelora Chemicals supply?+
We supply general-purpose (GPPS) and high-impact (HIPS, across a range of rubber contents) Polystyrene, across standard melt-flow-rate ranges for injection moulding, sheet extrusion and foam applications. Each grade ships with a certificate of analysis.
05Is Polystyrene hazardous?+
No; it has a low hazard profile in solid pellet form and is not classified as hazardous under GHS. The main handling precautions are combustible-dust control from fines generated during conveying, and standard flammability precautions where foam-grade resin is converted.
06Why is HIPS tougher than GPPS if both are polystyrene?+
GPPS is entirely amorphous with no second phase to blunt a propagating crack, which is why it fractures in a brittle manner despite its glass-like clarity; HIPS is engineered during polymerisation to contain a finely dispersed rubber (polybutadiene) phase grafted to the polystyrene matrix, and those rubber particles absorb and redirect crack energy, giving HIPS substantially better impact resistance at the cost of the clarity and some of the stiffness that unmodified GPPS retains.
07What packing options are available?+
Standard packing is 25 kg bags on pallet, with 1,000 kg jumbo bags or bulk hopper truck shipment available for larger volumes.
08How long does delivery take?+
Typical lead time is two to three weeks plus transit, depending on whether the grade is ex-stock or made to order and your destination port. A firm date is confirmed in the written quotation.
09Can I get a sample before placing a bulk order?+
Yes. Pre-shipment samples and a batch certificate of analysis can be arranged so your QC team can verify the specification before committing to volume.
10Do you supply the benzene and ethylene feedstocks used to make styrene monomer as well?+
Yes, we supply both Benzene and Ethylene, the two feedstocks alkylated together to make ethylbenzene, the precursor dehydrogenated to styrene monomer.
Request This Grade

Need Polystyrene on spec, on time?

Send us your required grade (GPPS/HIPS), melt flow rate, application and destination port. Our desk quotes most enquiries within one working day.