Lexan 121R: specs and equivalent grades
NexPoint Materials (formerly SABIC) polycarbonate (PC), 17.5 MFR class, with internal mold release, for small, intricate parts. Published data, grades from other producers to ask about, and how to request a quote from one gaylord.
Request a QuoteThe short answer
Lexan 121R is a polycarbonate (PC) with internal mold release, sold for injection molding of small, intricate parts. LEXAN began as a GE Plastics brand and was later sold by SABIC; in the Americas and Europe the LEXAN business is now NexPoint Materials, and SABIC sells LEXAN elsewhere. Published melt flow is 18 g/10 min, measured at 300°C / 572°F, 1.2 kg, ASTM D1238 (the producer's description calls it a 17.5 MFR grade), and specific gravity is 1.20 (ASTM D792). Grades from other producers to ask about include Makrolon 2405, Iupilon S-3000R and Wonderlite PC-122. They are not identical, so compare the data sheets and run a trial before switching.
Buying Lexan 121R: one gaylord to a railcar · supplier COA on every prime lot · ships from 22+ partner warehouse locations · a polymer chemist checks the grade code before we quote · we aim to quote within one to three business days
Have a part number or drawing callout?
Paste it as written. A polymer chemist will tell you which grade it calls for, suggest equivalents and quote it by email.
Lexan 121R specs from the data sheet
Typical values from the SABIC data sheet for Lexan 121R (distributor copies; NexPoint says existing SABIC documents stay valid until they are reissued under its name). Typical values are not specifications; the lot COA shows what you actually receive. Values only compare at the same test method and condition.
| Property | Value | Test method or note |
|---|---|---|
| Producer (brand owner) | NexPoint Materials in the Americas and Europe (formerly SABIC); SABIC elsewhere | Data sheet shows SABIC Innovative Plastics; NexPoint is SABIC's former engineering thermoplastics business, now independent; it says existing SABIC documents stay valid during its transition |
| Polymer | Polycarbonate (PC), nonhalogenated, with internal mold release | |
| Process | Injection molding; described for small, intricate parts | |
| Melt flow | 18 g/10 min (described as a 17.5 MFR grade) | 300°C / 572°F, 1.2 kg, ASTM D1238 |
| Density | Specific gravity 1.20 (ASTM D792) | |
| Flexural modulus, 50 mm span | 2,340 MPa (340,000 psi) | ASTM D790 |
| Tensile strength at yield / break | 62.1 MPa (9,000 psi) / 68.9 MPa (10,000 psi) | ASTM D638 |
| Elongation at break | 130 % | ASTM D638 |
| Notched Izod impact, 23°C / 73°F | 690 J/m (13 ft-lb/in) | ASTM D256 |
| HDT 0.45 MPa / 1.8 MPa, unannealed, 6.4 mm | 138°C / 280°F; 129°C / 264°F | ASTM D648 |
| Vicat softening temperature | 154°C / 309°F | ASTM D1525, rate B, 50 N |
| Mold shrinkage, flow, 3.2 mm | 0.50–0.70 % | Producer internal method |
| Light transmittance / haze, 2.54 mm | 88.0 % / 1.0 % | ASTM D1003 |
| Flammability | UL 94 HB at 0.711 mm; RTI 130°C (electrical, impact, strength) | UL 94, UL 746 |
| Drying | 121°C / 250°F for 3–4 h; max moisture 0.020 % | Producer processing guide |
| Melt / mold temperature | 282–304°C (540–579°F) / 71–93°C (160–199°F) | Producer processing guide |
| Additives | Internal mold release; halogen-free | |
| Food contact | The data sheet makes no food-contact statement. Ask for the producer's regulatory letter for the exact grade and color. |
Source data sheets are listed at the bottom of this page. Confirm against the current sheet for your exact grade code and color.
Grades to ask about instead of Lexan 121R
These grades from other producers have similar published specs. None is a drop-in replacement: additive packages, flow at molding shear rates, color and approvals differ. If your part, drawing or customer approval names Lexan 121R, any change needs your approval and usually a trial.
| Grade | Producer | Melt flow | Density | Key property | How it compares |
|---|---|---|---|---|---|
| Makrolon 2405 | Covestro | MFR 20 g/10 min; MVR 19 cm³/10 min (300°C / 572°F, 1.2 kg, ISO 1133) | 1.20 g/cm³ (ISO 1183) | Tensile modulus 2,400 MPa (ISO 527); HDT 124°C at 1.8 MPa (ISO 75); UL 94 V-2 at 0.75 mm, HB at 2.7 mm | Closest match. Low-viscosity general-purpose PC with easy release, offered in transparent, translucent and opaque colors. Data are ISO, so the MFR is not directly comparable with 121R's ASTM value, though both use 300°C / 1.2 kg. Covestro says regulated uses such as food contact or medical need its written approval. Quote this alternative › |
| Iupilon S-3000R | Mitsubishi Engineering-Plastics | 16.5 g/10 min (300°C / 572°F, 1.2 kg) | Specific gravity 1.20 (ASTM D792) | Notched Izod 16.5 ft-lb/in (881 J/m) (ASTM D256); HDT 128°C at 1.8 MPa (ASTM D648); UL 94 V-2 at 1.59 mm | Partial match. Similar flow, density and heat resistance, with a higher notched Izod on the sheet. Values come from a U.S. distributor (PTS) copy; the sheet does not state a mold release, so confirm the additive package. Quote this alternative › |
| Wonderlite PC-122 | Chi Mei | 22 g/10 min (300°C / 572°F, 1.2 kg, ASTM D1238) | 1.2 (ASTM D792) | Notched Izod 15.4 ft-lb/in (about 820 J/m) at 3.2 mm (ASTM D256); HDT 125°C unannealed (ASTM D648, load not stated); UL 94 V-2 at 1.5 mm | Partial match. Chi Mei lists it as a high-flow PC, about 20 % higher MFR than 121R. Expect imported supply; the sheet does not state the plant, so confirm origin. The sheet does not state a mold release. Quote this alternative › |
From each producer's published data. Brand owners and grade names change; confirm on the current data sheet.
Typical uses for Lexan 121R
From the producer's data sheet and published listings:
- Small, intricate injection-molded parts (the producer's own description)
- Clear or colored parts that need PC toughness: the sheet lists 88 % light transmittance at 2.54 mm
- Parts where an internal mold release helps ejection in fast or multi-cavity tools
- Electrical parts that need a UL listing: HB at 0.711 mm with a 130°C RTI
What to check before you switch
- Brand owner change: in the Americas and Europe, Lexan 121R now comes from NexPoint Materials. NexPoint says grades and plants stay the same and that SABIC-branded data sheets and certificates remain valid while documents are reissued. Ask for the current sheet and UL file under the new name if your approval references the producer.
- Mold release matters. 121R has an internal release; Makrolon 2405 lists easy release, but the Iupilon and Chi Mei sheets above do not state one. Ejection, part sticking and downstream painting or bonding can change.
- Flame ratings differ by grade and thickness: 121R lists HB at 0.711 mm, while Makrolon 2405, Iupilon S-3000R and Wonderlite PC-122 list V-2 at various thicknesses. If your drawing calls out a UL rating, check the exact yellow card for the substitute.
- Polycarbonate must be dry. The 121R sheet asks for 121°C / 250°F for 3–4 hours and 0.020 % maximum moisture; wet PC splays and loses impact strength. See our resin drying guide.
- Same producer family: Makrolon 2407 is Covestro's UV-stabilized version of 2405 (MVR 19 cm³/10 min). Ask about it if the part sees sunlight or fluorescent light.
- Compare melt flow, density and impact only at the same test condition and method (ASTM vs. ISO results differ).
- Ask for the producer's food-contact or regulatory letter for the exact grade if the part needs one.
- Run a trial lot and check shrinkage, cycle time and appearance before you switch production.
Buying Lexan 121R: price, lead time and lot size
- Lot size. From one gaylord to a railcar. See gaylord, LTL and truckload for typical weights per box.
- Where it ships from. 22+ partner warehouse locations. Material already in a partner warehouse usually moves sooner than a grade that has to come from the producer; your quote says which applies.
- Price. We do not publish prices because they move with feedstock, freight and order size. What moves your price most: lot size, color, ship-to region, and whether you need Lexan 121R itself or can accept a matched alternative. See how resin is priced and the monthly market update.
- Paperwork. Supplier COA on every prime lot (what a COA shows). Ask for the producer’s regulatory letter or UL file if your part needs them.
- Trying an alternative? Start with one gaylord as a trial lot, molded and checked before you commit a full release.
- If Lexan 121R itself is not available. Some branded grades are sold only through the producer’s own channels or go on allocation. If we cannot source it, we tell you, then quote a matched alternative with a side-by-side comparison.
Send the grade code, your annual volume and ship-to location. A polymer chemist checks it before we quote; we have been in the resin business for 30+ years. For several grades at once, use the resin RFQ template.
Trade names belong to their owners. ResinBridge is not affiliated with these producers; grade names are used only to identify the material. Data reflects published sheets as of October 2026.
Sources
- SABIC LEXAN 121R data sheet (distributor copy, PDF)
- SABIC LEXAN 121R data sheet (second distributor copy, PDF)
- LEXAN 121 data sheet, IDES 2011 (Protolabs, PDF)
- NexPoint Materials transition hub
- Covestro Makrolon 2405 product data
- Covestro Makrolon 2407 product data
- Mitsubishi Iupilon S3000R data sheet (distributor copy, PDF)
- Chi Mei Wonderlite PC-122 data sheet (PDF)
- nexpointmaterials.com product page
Common questions
What is Lexan 121R?
Lexan 121R is a polycarbonate (PC) with internal mold release, sold for injection molding of small, intricate parts. In the Americas and Europe it now comes from NexPoint Materials, the former SABIC engineering thermoplastics business.
What is the melt flow of Lexan 121R?
18 g/10 min, measured at 300°C / 572°F, 1.2 kg, ASTM D1238, per the published data sheet. The producer's description calls it a 17.5 MFR grade.
What is equivalent to Lexan 121R?
Grades from other producers to ask about include Makrolon 2405, Iupilon S-3000R and Wonderlite PC-122. None is identical; compare data sheets and run a trial, and get approval if your part names Lexan 121R.
Is Lexan 121R food-contact compliant?
The data sheet makes no food-contact statement. Ask for the producer's regulatory letter for the exact grade and color before using it in a food-contact part.
Can ResinBridge quote Lexan 121R?
We quote Lexan 121R when our supply partners can source it. If they cannot, we say so up front and quote a matched alternative, named on the quote with its data sheet, so you can decide whether to trial it. We quote Lexan 121R where we can source it, or a matched alternative, and say clearly which one you would get. Orders start at one gaylord; U.S. and Canada only.
If your grade is not listed, tell us what you run. We source commodity, engineering and specialty resins.
Need Lexan 121R or an equivalent?
A polymer chemist reviews every request, then matches your grade or finds a matched alternative 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
Quote Lexan 121R or a matched alternative
A polymer chemist checks the data sheet and tells you exactly what you would get before you order.
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