Polyarylate supplier: UV stability without coatings
UV-stable, heat-resistant and transparent: polyarylate keeps its mechanical properties outdoors without coatings. Expect the surface to yellow as it weathers, so it is not the choice where color or water-clear optics must stay unchanged.
One gaylord to a truckload · A polymer chemist reviews every quote · Every prime lot from our suppliers ships with a COA
Updated October 2026
Request a Quote- Impact strength
- Good
- Heat (HDT)
- ~120-175°C
- Clarity
- Transparent
At a glance
- Form
- Pellets
- Order size
- One gaylord to a truckload
- Grades
- Transparent general-purpose grades · High-heat grades · UV-protective coextrusion/capstock
- Paperwork
- Supplier COA on every prime lot
- Ships to
- U.S. and Canada
- Sourcing
- Matched to your spec
The short answer
Polyarylate is a transparent aromatic polyester for outdoor parts that must keep their toughness and heat resistance in sunlight without a hardcoat. Pick it over polycarbonate when UV embrittlement is the problem, and over acrylic when heat or impact is. Two things go wrong: the surface yellows as it weathers, and wet resin breaks down in the barrel, so drying is not optional.
Grades we source
Tap a grade to add it to your quote request.
About Polyarylate
Polyarylates are aromatic polyesters with inherent UV resistance: the surface photo-rearranges into its own protective layer (the layer is yellow), so weatherability doesn’t depend on additives or hardcoats. Use it where polycarbonate loses toughness outdoors and acrylic can’t take the heat or impact, and where some yellowing is acceptable.
Common applications
- Outdoor lenses and covers
- Solar and lighting applications
- Exterior electrical hardware
- Safety equipment with sun exposure
Typical properties
| Impact strength | Good |
|---|---|
| Heat (HDT) | ~120-175°C |
| Clarity | Transparent |
| Chemical resistance | Moderate |
| Relative cost | High |
Property ranges are general guidance and vary by grade and supplier; a polymer chemist confirms the exact spec against the data sheet and certificate of analysis for your application.
Which grade to ask for
Neat polyarylate gives the best weathering; blends trade some of it for easier processing.
| Grade type | Use it for | Watch out for |
|---|---|---|
| Transparent general-purpose | Outdoor lenses, covers and sight windows | Surface yellows with exposure; attacked by aromatic and chlorinated solvents |
| High-heat grades | Lamp covers and parts near heat sources | Stiffer melt; harder to fill thin walls; needs higher melt and mold temperatures |
| Blends with PC | Outdoor parts that need easier molding and better weathering than plain PC | Less UV resistance than neat polyarylate; ask for weathering data on the blend itself |
| Blends with polyesters | Parts that need better flow and chemical resistance | Lower heat resistance; moisture-sensitive like other polyesters |
| Capstock and coextrusion grades | A UV-protective layer over PC or other sheet and profile | Melt viscosity must match the substrate, and layer adhesion needs to be checked |
Typical starting points. Grades vary, so confirm on the data sheet for the exact grade.
Processing notes
- Drying. Required. Polyarylate is a polyester, so water at melt temperature cuts the chains. Published examples dry at about 120°C / 248°F for 4–8 h or longer. Take the temperature and moisture limit from the grade sheet; about 0.02% is a common target for hydrolysis-sensitive resins. Use a dehumidifying dryer. See the drying chart for other resins.
- Melt temperature. Neat grades typically run at about 340–370°C / 644–698°F; blends with polyesters run lower. The melt is stiff, so expect high injection pressure and use generous gates and runners.
- Mold temperature. Typically about 100–140°C / 212–284°F, by grade. A hot mold lowers molded-in stress, which helps both solvent resistance and outdoor life.
- Shrinkage. Unfilled grades typically about 0.6–0.9%, close to even in both directions, like other amorphous resins.
- Regrind. Producer limits are not widely published. Treat it like other clear, hydrolysis-sensitive resins: start at no more than about 15–25% of the same grade, dried like virgin, confirm with part testing, and use less for optical parts. Yellowing and specks show first.
- Most common defect. Splay, bubbles and a yellow cast at the gate from wet or overheated resin. Short shots on thin walls are next, because the melt is stiff.
What to put on the purchase order
- Grade type. Neat polyarylate or a blend (with PC or a polyester). Weathering and heat differ a lot between them.
- Weathering data. Ask for the grade’s published weathering results (accelerated or outdoor exposure), including color or yellowness change, not just initial clarity.
- Optical values. Light transmission and haze from the data sheet, and whether the COA reports a color or yellowness value.
- Melt flow and test condition. Copy both from the data sheet so the COA value can be compared.
- Outdoor electrical parts. UL recognition, including any UL 746C outdoor-suitability rating (f1 means the material passed both the UV and water exposure tests; f2 means it met them only in part), is grade-specific and color-specific; check the grade’s listing on UL Product iQ.
- Packaging. Sealed moisture-barrier bags or lined boxes, resealed between runs.
When to consider something else
- If the color must not shift and the part can be opaque, look at ASA.
- If the part must stay water-clear outdoors and heat and impact are moderate, look at acrylic; see PC vs. acrylic.
- If a UV-stabilized or capped grade is enough, polycarbonate costs less and is easier to source.
- If steam or higher continuous heat matters more than sunlight, look at PSU / PPSU.
- For a wider comparison, see best plastics for outdoor UV.
Common questions
What is polyarylate used for?
Outdoor transparent parts that need heat resistance and toughness in sunlight: lenses, covers, solar and lighting parts, exterior electrical hardware and safety equipment. It is also used as a UV-protective capstock over other plastics.
Does polyarylate turn yellow outdoors?
Yes. Its surface rearranges under UV into a protective layer, and that layer is yellow. The part keeps its mechanical properties, but the color changes, so it is not the choice where color or water-clear optics must stay the same.
Is polyarylate better than polycarbonate outdoors?
For keeping toughness in sunlight without a coating, usually yes. Unprotected polycarbonate loses impact strength outdoors, while polyarylate protects itself. Polycarbonate costs less and has many UV-stabilized and coated options, so compare weathering data for the actual grades.
Does polyarylate need to be dried?
Yes. It is a polyester, and water at melt temperature breaks down the polymer, causing splay and brittle parts. Dry to below about 0.02% in a dehumidifying dryer, following the grade’s data sheet.
Tell us the Polyarylate grade you run now
A polymer chemist reviews every request, then matches your grade or finds a qualified equivalent and prices it.
What to send for an accurate quote
- The grade name, from any supplier, or a data sheet
- Color (natural, black or a custom match)
- Fill type and percentage, if any
- Melt flow, if you know it
- Quantity for this order and what you use in a year
- Ship-to city and state or province
Polyarylate quotes for outdoor parts
Send the polyarylate grade or the heat and UV exposure the part sees, plus volume; a polymer chemist reviews it and we quote.
Request a QuoteNot sure which grade to ask for?
Send the grade you run now, or describe the part. A polymer chemist reviews every request.