FabDigit

PS

GB GB/T 4454 · ISO 1043-1 PS · also Styron, Polystyrol

PS is general-purpose polystyrene (GPPS), a rigid, transparent amorphous styrenic thermoplastic supplied to ASTM D1996 and GB/T 4454 and sold under names such as Styron and Polystyrol.

Budget cost $

Reference datasheet — PS is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.

Values for the GPPS condition

PS grades and fills

PS is supplied in 6 conditions, soft to hard. GPPS is the default FabDigit quotes; the values on this page are for it.

Compare all 6 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
Expanded polystyrene foam
Pick for low-cost thermal insulation, protective packaging and lost-foam patterns where mechanical loads are light.0.28
Antistatic / ESD HIPS
Pick for electronics trays, carriers and IC packaging where surface charge must be dissipated.21242570 Shore D
High-impact polystyrene
Pick when parts must survive handling/drop loads or be thermoformed into tough opaque housings, refrigerator liners and packaging trays.242540100 HRR
PS-FR
Pick for TV/appliance housings and electrical enclosures needing UL 94 V-0 at 1.5–3 mm; accept lower impact, higher density and reduced light stability.2620
Medium-impact polystyrene
Compromise grade when some toughness is needed but GPPS-like stiffness and translucency must be kept.28331578 Shore D
GPPSDefault
General-purpose (crystal) polystyrene, unfilled transparent
Pick for clarity, stiffness, gloss and lowest cost where impact loading and solvents are absent.462.575 HRM

Supply forms, finishes and certifications

Ways PS is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.

OptionWhat it isType
FOOD
Food-contact / medical grade GPPS-HIPSCertification

What is PS?

PS is general-purpose polystyrene (GPPS), a rigid, transparent amorphous styrenic thermoplastic supplied to ASTM D1996 and GB/T 4454 and sold under names such as Styron and Polystyrol. Engineers select it for optical clarity, stiffness, dimensional stability and the lowest cost in the styrenic family; it is stocked as moulding pellets, extruded sheet, film and expanded (EPS) forms at 1.05 g/cm³ with 46 MPa tensile strength. The trade-off is brittleness at 2.5 % elongation, plus poor resistance to hydrocarbons, ketones and UV. HIPS or SAN is the usual step up when impact or chemical resistance is required. PS has a density of 1.05 g/cm³ (0.0379 lb/in³), lighter than 69% of polymer grades. Its glass-transition temperature is 100°C (212 °F). PS has a yield strength of 45 MPa (6.53 ksi) and a tensile strength of 46 MPa (6.67 ksi) — weaker than 58% of polymer grades. Elongation at break is 2.5% and the elastic modulus is 3.2 GPa (0.464 Msi).

What is PS used for?

  • Disposable cutlery and cups
  • CD/DVD cases
  • Packaging inserts
  • Lab-ware
  • Optical light diffusers
  • Model kits

Advantages

  • Polishes to a fine finish — 80/100, better than 89% of polymer grades
  • Low moisture uptake — 0.05%, better than 84% of polymer grades
  • Stiff — 3.2 GPa (0.464 Msi), better than 77% of polymer grades
  • Low embodied carbon — 3.4 kg CO₂/kg, better than 76% of polymer grades

Limitations

  • Needs corrosion protection — 55/100, worse than 94% of polymer grades
  • Limited ductility — 2.5%, worse than 89% of polymer grades
  • Low fracture toughness — 1 MPa·√m (0.91 ksi·√in), worse than 87% of polymer grades
  • Limited service temperature — 65°C (149 °F), worse than 83% of polymer grades
  • Poor heat conductor — 0.14 W/m·K (0.0809 BTU/hr·ft·°F), worse than 81% of polymer grades

PS properties

Typical room-temperature values for PS-GPPS; bars are the position among polymer grades.

Physical6

PS has a density of 1.05 g/cm³ (0.0379 lb/in³), lighter than 69% of polymer grades. Its glass-transition temperature is 100°C (212 °F).

Density1.05 g/cm³0.04 lb/in³
Glass Transition (Tg)100°C212 °F
Water Absorption (24 h)0.05%
Water Absorption (Saturation)0.2%
Refractive Index1.59
Light Transmission90%

Mechanical17

PS has a yield strength of 45 MPa (6.53 ksi) and a tensile strength of 46 MPa (6.67 ksi) — weaker than 58% of polymer grades. Elongation at break is 2.5% and the elastic modulus is 3.2 GPa (0.464 Msi).

Elastic (Young's) Modulus3.2 GPa0.46 Msi
Shear Modulus1.2 GPa0.17 Msi
Bulk Modulus4 GPa0.51 Msi
Poisson's Ratio0.35
Tensile Strength (Ultimate)46 MPa6.7 ksi
Yield Strength (0.2% offset)45 MPa6.5 ksi
Elongation at Break2.5%
Compressive Strength95 MPa13.8 ksi
Compressive Modulus3.2 GPa0.46 Msi
Flexural Strength80 MPa11.6 ksi
Flexural Modulus3.2 GPa0.46 Msi
Shear Strength32 MPa4.6 ksi
Fracture Toughness (K_IC)1 MPa·√m0.91 ksi·√in
Izod Impact, Notched20 J/m0.37 ft·lbf/in
Hardness, Shore D85 Shore D
Hardness, Rockwell M75 HRM
Hardness, Rockwell R120 HRR

Thermal11

PS is rated for continuous service to 65°C (149 °F). It conducts heat at 0.14 W/m·K (0.0809 BTU/hr·ft·°F), worse than 81% of polymer grades. Thermal expansion is 70 µm/m·K (38.9 µin/in·°F).

Thermal Conductivity0.14 W/m·K0.08 BTU/hr·ft·°F
Specific Heat Capacity1,300 J/kg·K0.31 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)70 µm/m·K38.9 µin/in·°F
Max Service Temperature (continuous)65°C149 °F
Min Service Temperature-30°C-22 °F
Heat Deflection Temp. @ 0.45 MPa85°C185 °F
Heat Deflection Temp. @ 1.8 MPa78°C172 °F
Vicat Softening Point (B50)95°C203 °F
Flammability (UL 94)HB
Limiting Oxygen Index18%
Max Service Temperature (short-term)85°C185 °F

Electrical7

PS is an electrical insulator with a dielectric strength of 22 kV/mm (558.8 V/mil) and a resistivity of 1×10¹⁴ Ω·m.

Electrical Resistivity1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
Dielectric Strength22 kV/mm559 V/mil
Dielectric Constant (1 MHz)2.5
Dissipation Factor (1 MHz)2×10⁻⁴
Volume Resistivity1×10¹⁶ Ω·cm
Surface Resistivity1×10¹⁵ Ω
Comparative Tracking Index (CTI)600 V

Chemical & Environmental3

Corrosion resistance is good (55/100), worse than 94% of polymer grades. UV resistance is poor.

Corrosion ResistanceGood55/100
UV / Weathering ResistancePoor25/100
Chemical Resistance SummaryResists water, dilute acids, alkalis and alcohols; rapidly attacked or dissolved by aromatics, ketones, esters, chlorinated solvents, gasoline and many oils; environmental stress cracking is the usual failure mode.

Sustainability4

Producing a kilogram of PS takes about 87 MJ of energy and emits 3.4 kg of CO₂ — less than 77% of polymer grades. Typical recycled content is 2%.

Embodied Energy (primary production)87 MJ/kg37,403 BTU/lb
Embodied Carbon (primary production)3.4 kg CO₂/kg
Embodied Water200 L/kg24 gal/lb
Typical Recycled Content2%

Manufacturability8

PS's machinability is good (60/100, better than 51% of polymer grades); weldability very good (70/100); formability fair (45/100).

MachinabilityGood60/100
WeldabilityVery good70/100
Formability (cold)Fair45/100
PolishabilityVery good80/100
Mold Shrinkage0.5%
Melt Flow Rate8 g/10 min
Processing Melt Temperature (typ.)220°C428 °F
Mold Temperature (typ.)50°C122 °F

Common Calculations5

Specific Strength (UTS / density)calculated44 kN·m/kg
Specific Stiffness (E / density)calculated3 MN·m/kg
Modulus of Resiliencecalculated316 kJ/m³
Thermal Diffusivitycalculated0.1 mm²/s
Thermal Shock Resistance Indexcalculated0

Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.

Strength versus weight in the polymer family

Yield strength against density for every polymer grade FabDigit runs. PS is highlighted; hover a dot for its name, or open the interactive family chart.

0.1110100123Density (g/cm³)Yield strength (MPa) — log scalePS

Working with PS

Is PS easy to machine?

Machines fast with sharp positive-rake tools, high speed and light feeds; use air blast (no solvent/oil coolants) and avoid stress risers to prevent crazing and chip-out.

Can PS be welded?

Excellent solvent cementing (MEK, toluene, dichloromethane) and ultrasonic/hot-plate welding; do not attempt to weld to non-styrenics without adhesives.

Can PS be formed, bent or molded?

Very easy injection molding at 190–250 °C melt / 20–70 °C mold with 0.4–0.7 % shrinkage; HIPS and GPPS sheet thermoform and vacuum-form readily above ~130 °C.

PS chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
polybutadiene rubbergraft rubber phase in HIPS only4 – 127
mineral oil / lubricantinternal lubricant/flow aid in HIPS and easy-flow GPPS0 – 31.5
residual styrene monomerfood-grade limits per GB 4806.6 / EU 10/2011≤ 0.10.03
styrene (polystyrene homopolymer)GPPS: amorphous atactic polystyrene, Mw typically 200,000–300,000 g/molbalance

What surface finishes work on PS?

Molds to high gloss and can be printed, hot-stamped, vacuum-metallized or painted with PS-compatible (non-aggressive-solvent) systems; anneal machined parts near 70–80 °C to relieve stress before contact with solvents.

Equivalent designations

Standards and trade names that resolve to PS in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.

ISO
1043-1 PS
GB (China)
GB/T 4454
Trade names
StyronPolystyrol
Also called
GPPS

How much does PS cost?

PS is a budget-cost polymer ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.

PS — frequently asked

What is PS used for?

PS is typically used for disposable cutlery and cups, CD/DVD cases, packaging inserts, lab-ware, optical light diffusers and model kits. In short: lowest-cost clear thermoplastic; stiff but notch-sensitive; best solvent-cementing styrenic.

What is the yield strength of PS?

PS has a typical yield strength of 45 MPa (6.53 ksi) and a tensile strength of 46 MPa (6.67 ksi) — weaker than 58% of polymer grades. Strength varies by condition: see the 6 listed tempers.

Is PS easy to machine?

Reasonably — machinability is rated good (60/100, better than 51% of polymer grades). Machines fast with sharp positive-rake tools, high speed and light feeds; use air blast (no solvent/oil coolants) and avoid stress risers to prevent crazing and chip-out.

Can PS be welded?

Yes — weldability is rated very good (70/100). Excellent solvent cementing (MEK, toluene, dichloromethane) and ultrasonic/hot-plate welding; do not attempt to weld to non-styrenics without adhesives.

What surface finishes work on PS?

Molds to high gloss and can be printed, hot-stamped, vacuum-metallized or painted with PS-compatible (non-aggressive-solvent) systems; anneal machined parts near 70–80 °C to relieve stress before contact with solvents.

Can PS be formed, bent or molded?

Very easy injection molding at 190–250 °C melt / 20–70 °C mold with 0.4–0.7 % shrinkage; HIPS and GPPS sheet thermoform and vacuum-form readily above ~130 °C.

What is the maximum service temperature of PS?

PS is rated for continuous use to about 65°C (149 °F), and briefly to 85°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between PS GPPS and PS ESD?

GPPS is the default condition — pick for clarity, stiffness, gloss and lowest cost where impact loading and solvents are absent. ESD: pick for electronics trays, carriers and IC packaging where surface charge must be dissipated. Yield strength is 45 MPa in GPPS versus 21 MPa in ESD.

How much does PS cost?

PS is a budget-cost polymer ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.

Sources

  1. ISO 1043-1 Plastics — Symbols and abbreviated terms — ISO (2011)
  2. ASTM D4549 Standard Classification System for Polystyrene Molding and Extrusion Materials — ASTM (2020)
  3. Engineered Materials Handbook, Vol. 2: Engineering Plastics — ASM International (1988)
  4. STYRON / Trinseo GPPS and HIPS grade datasheets — Trinseo (2023)
  5. CAMPUS plastics database — PS/HIPS entries — CWFG (2024)
  6. PlasticsEurope Eco-profile: General Purpose Polystyrene — PlasticsEurope (2020)
  7. GPPS/HIPS (2026)

Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.