Orthophthalic Fire-Retardant Gelcoat Resin
SPR 201 FR-GCThixotropic fire-retardant gelcoat, SPR 201 familySPR 201 · Orthophthalic Polyester Resins
Thixotropic fire-retardant gelcoat for the mould-face surface of fire-retardant FRP components.
Review the official product data sheet for specifications and application information.
Price
Price on Request
Industrial resin pricing varies based on:
- Order Quantity
- Resin Grade
- Current Raw Material Rates
Product details
| Catalogue Code | SPR 201 FR-GC |
|---|---|
| Resin Chemistry | Orthophthalic unsaturated polyester gelcoat, fire-retardant |
| Supply Condition | Non-accelerated · thixotropic |
| Reference Cure System | MEKP 1.5–2.0% — added during use |
Typical specification
| Appearance | Milky white to grey opaque liquid; custom-tinted variants where supplied |
|---|---|
| Viscosity, High Shear | 5,000–11,000 cPs at 25 °C |
| Viscosity, Low Shear | 30,000–45,000 cPs at 25 °C |
| Gel Time | 9–16 minutes at 25 °C |
| Specific Gravity | 1.35–1.55 |
| Styrene Content | 17–25% by weight |
Typical values from the Samrat Poly Resins product catalogue, 2026 edition. They are not guaranteed specifications or finished-component properties; confirm the current values for your order and trial the grade on your own process.
SPR 201 FR-GC is the fire-retardant gelcoat of the orthophthalic SPR 201 family: a thixotropic surface coat applied to the mould face before lay-up, listed for rail and metro composite components, automotive FRP components and as the surface gelcoat for fire-retardant FRP laminates. It is supplied non-accelerated and thixotropic, with MEKP added separately during use. No fire classification or test result is published for this grade.
The catalogue pairs this gelcoat with the fire-retardant laminating resin of the same project — Fire Retardant Resin or Halogen-Free Fire-Retardant Resin. The terephthalic alternative is SPR 401 FRGC; the general-purpose white gelcoat is GP Gelcoat Resin.
Key features
- Thixotropic fire-retardant gelcoat (SPR 201 FR-GC)
- Typical viscosity 5,000–11,000 cPs high shear, 30,000–45,000 cPs low shear
- Typical gel time 9–16 minutes at 25 °C
- Supplied non-accelerated; MEKP added during use
Applications
- Rail and metro composite components
- Automotive FRP components
- Surface gelcoat for fire-retardant FRP laminates
Product role
A gelcoat is the first layer into the mould and the outer surface of the finished part, so on a fire-retardant component it is part of the fire-exposed face. The catalogue therefore lists a fire-retardant gelcoat to pair with its fire-retardant laminating resins rather than a general-purpose gelcoat.
Fire-retardant does not establish a certified fire rating: classifications apply to the tested finished construction. Share the project standard and component details before selection.
Supply and cure
- Supply condition
- Non-accelerated · thixotropic
- Reference cure system
- MEKP 1.5–2.0% — added during use
Processes and where this grade fits
SPR 201 FR-GC is a thixotropic gelcoat. It goes into the mould first and becomes the outer, fire-exposed surface of the part.
| Process or use | Role of this grade | What to confirm |
|---|---|---|
| Brush or spray gelcoat on open moulds | Listed role — surface coat of fire-retardant parts | Film thickness, sag on vertical faces and the gel before the first laminate |
| Rail and metro composite components | Listed role | The rail fire standard and the tested construction |
| Automotive FRP components | Listed role | The component and the vehicle maker’s requirement |
| Laminate behind the gelcoat | Use a fire-retardant laminating resin | SPR 201 FR or SPR 201 FR (HF) |
| Non-fire-retardant cosmetic surfaces | Not this grade’s role | GP Gelcoat Resin or ISO Gelcoat |
Process-selection considerations
- Choose a fire-retardant gelcoat when the part has a fire requirement: the gelcoat is the first surface a fire reaches.
- Pair it with the fire-retardant laminating resin of the project and test them together. A fire result belongs to the whole build.
- Its two viscosity readings — 5,000–11,000 cPs at high shear and 30,000–45,000 cPs at low shear — describe a gelcoat that flows under the brush or gun and holds on the mould. Confirm that on your equipment.
- Colour: supplied milky white to grey, with custom-tinted variants where supplied. Agree the colour before the trial, because pigment is part of the tested surface.
- The reference cure is MEKP at 1.5–2.0%; gel time is 9–16 minutes at 25 °C typical.
Limitations and trial requirements
- No fire classification is published for the gelcoat. Fire-retardant describes the formulation; the classification belongs to the tested finished part.
- The catalogue does not publish gloss, hardness, weathering or water-resistance values for this grade.
- Film thickness, application temperature and back-up timing affect surface quality; establish them on the production mould.
- Trial the grade on the real part, mould and shop conditions before production. The catalogue values are typical liquid-resin properties, not guaranteed limits or finished-part performance.
Before you select this grade
- The values on this page are typical. Final selection should be confirmed against your own process, a trial result and the current technical documentation for the grade.
- The Technical Data Sheet linked on this page carries these same typical values. No Safety Data Sheet is published on this site for this grade; request current safety information before use.
- Never mix a concentrated peroxide initiator directly with a cobalt accelerator. Add each to the resin separately, according to the confirmed process.
- Store resin, initiators and accelerators separately, in original sealed containers, cool, shaded and away from heat and ignition sources. Use suitable personal protective equipment and adequate ventilation.
