Quick facts
- Catalogue code
- SPR 201 CTG
- Chemistry
- Thixotropic orthophthalic unsaturated polyester
- Role
- Sag-resistant lay-up on vertical and large surfaces
- Isophthalic counterpart
- SPR 301 CT
The problem this grade solves
Cooling-tower casings, fan stacks, louvres and wind-turbine parts are large, and much of their surface is vertical or steeply curved. A free-flowing laminating resin drains down such a surface before it gels, leaving the top of the laminate resin-starved and the bottom resin-rich. SPR 201 CTG is the orthophthalic grade the supplier makes for that situation.
The catalogue lists it for cooling-tower FRP components, wind-turbine FRP components and sag-resistant lay-up on vertical surfaces, and describes it as a thixotropic grade.
What thixotropic means in practice
A thixotropic resin thins while it is being worked — rolled, brushed or sprayed — and thickens again once it is left alone. That lets it wet the reinforcement during application and then stay where it was placed on a vertical surface until it gels.
The catalogue gives SPR 201 CTG the same headline values as SPR 201 GPC: 350–450 cPs, a gel time under 8 minutes and 33–40% styrene, supplied non-accelerated with a reference cure of MEKP 1.5% and cobalt octoate 0.4%, each added separately. A single viscosity figure does not describe thixotropy; if your process depends on it, ask for the grade’s behaviour to be confirmed for your application method.
Selection questions
Will the laminate stay wet, warm or exposed to water-treatment chemicals over its life? How much of the part is vertical? Is it built by hand lay-up or spray-up? The first question decides the chemistry; the others decide whether a thixotropic grade is worth specifying at all.
Limitations and when to choose something else
SPR 201 CTG is orthophthalic. Where a tower’s service is demanding — warm, continuously wet, or with aggressive treatment chemicals — the catalogue’s isophthalic route is SPR 301 CT, listed with heat, chemical and corrosion resistance. For flat panels that do not need sag resistance, a standard laminating grade such as SPR 201 GPC is the simpler choice.
The resin data does not guarantee the life of a finished tower component. Confirm with a trial on your own process.
Source, roles and the Nepal enquiry path
The values on this page are the typical specification printed for SPR 201 CTG in the supplier’s 2026 product catalogue. Samrat Poly Resins has since published a Technical Data Sheet for this grade, linked from the product page; its figures and the catalogue’s agree, and the catalogue is the source named beside every figure here.
Samrat Poly Resins, India manufactures the grade and issues its technical information. Samrat FRP Traders is the Nepal supplier and importer and handles enquiries; price, packaging, lead time and stock in Nepal are confirmed on enquiry.
Key properties
| Property | Typical value |
|---|---|
| Appearance | Clear liquid |
| Viscosity | 350–450 cPs |
| Gel time | Under 8 minutes |
| Styrene content | 33–40% |
| Supply condition | Non-accelerated |
| Reference cure system | MEKP 1.5% + Cobalt Octoate 0.4% — added separately during use |
Source: Samrat Poly Resins, India — product catalogue, 2026 edition (typical specification). Typical values describe the grade; they are not batch guarantees or acceptance limits.
Frequently asked questions
Is SPR 201 CTG the same resin as GP Clear with an additive?
The catalogue lists it as its own thixotropic grade that shares GP Clear’s typical viscosity, gel time and styrene values. It does not publish a formulation, so treat it as a separate grade.
Which cooling-tower grade suits a demanding service?
The catalogue’s isophthalic option is SPR 301 CT, listed with heat, chemical and corrosion resistance. The service conditions decide between the two.
Is it used for wind-turbine parts?
The catalogue lists wind-turbine FRP components among its uses. Suitability for a specific structural part has to be confirmed by the part’s own design and testing.