Butanox M-50 is a general purpose methyl ethyl ketone peroxide (MEKP) for curing unsaturated polyester resins in the presence of a cobalt accelerator at room and elevated temperatures. As one of the recommended international brand products in our organic peroxide range, it is supplied with supply chain resource support for fabricators sourcing curing systems for gelcoat resins, laminating resins, lacquers, and castings.
Product Specifications
Specifications
| Appearance | Clear colorless liquid |
| Total active oxygen | 8.8-9.0 % |
Characteristics
| Density, 20 °C | 1.180 g/cm³ |
| Viscosity, 20 °C | 24 mPa.s |
Key Benefits of This MEKP Curing Agent
- Medium-reactive, general purpose curing performance for GRP applications
- Guaranteed low water content and absence of polar compounds
- Suitable for room and elevated temperature curing with a cobalt accelerator
- Can support light-resistant parts compared to a benzoyl peroxide/amine accelerator system
- Very suitable for GRP marine applications due to its formulation profile
Applications Across Industries
Butanox M-50 supports a wide range of end-use applications across several industries:
- Marine: GRP hulls and decks requiring low water content and polar-compound-free curing
- Construction: castings and reinforced construction components
- Automotive parts: general purpose composite curing for structural and body parts
- Petrochemical: laminating resin curing for corrosion-resistant composite parts
This range of applications reflects why this MEKP is often described as the work horse in GRP curing systems, giving fabricators a single curing agent that can be standardized across gelcoat, laminating, and marine composite production.
Why Butanox M-50 Suits Marine GRP Applications
Practical experience over many years has proven that the guaranteed low water content and the absence of polar compounds in Butanox M-50 make this peroxide very suitable in GRP products for marine applications, where osmosis resistance and hull durability are critical concerns. This is why Butanox M-50 is frequently the MEKP advised when a fabricator’s primary application is marine GRP, as referenced by other MEKP grades in our range that are instead positioned for general purpose or extra-long gel time work.
The curing system built around Butanox M-50 and a cobalt accelerator is particularly suitable for gelcoat resins, laminating resins, lacquers, and castings. Compared to a benzoyl peroxide and amine accelerator system, this MEKP and cobalt combination may allow the manufacture of light-resistant parts, which can matter for gelcoat surfaces and other visible composite components exposed to UV light over time.
Curing System Considerations
Cure speed and gel time with the Butanox M-50/cobalt accelerator system depend on cobalt accelerator loading, ambient or process temperature, and the specific unsaturated polyester resin formulation being used. Fabricators should always run trial batches to confirm gel time and cure profile before committing to full production with a new resin and peroxide combination.
Because active oxygen content and water content directly affect cure consistency, fabricators should confirm current specifications against the latest technical data sheet before finalizing a curing schedule, particularly for marine applications where formulation consistency matters most.
What to Consider When Sourcing This MEKP
When sourcing Butanox M-50, fabricators typically evaluate active oxygen content, water content, and viscosity data alongside their specific resin system and target cure profile. Working with a supplier that can provide consistent documentation and responsive technical support can help reduce qualification time when approving a new peroxide grade for a production line.
Buyers switching between MEKP grades or suppliers should confirm current active oxygen and water content specifications for their specific resin and accelerator combination, since gel time and cure profile can shift meaningfully between nominally similar MEKP products.
General Handling and Storage Guidance
As with most organic peroxide products, this MEKP should be stored in a cool, well-ventilated location away from direct sunlight, heat sources, and incompatible materials such as accelerators or reducing agents, and used within the manufacturer’s recommended shelf life. Because organic peroxides are reactive materials, storage temperature and segregation from accelerators are important handling considerations.
Shelf life and specific storage temperature limits vary by batch and packaging format, so fabricators should always confirm current shelf life, recommended storage temperature, and handling precautions against the latest technical data sheet and safety data sheet for the specific batch they are working with.
Choosing Between Butanox M-50 and Other MEKP Grades
Thousands Chemicals also supplies Butanox M-60, Butanox LPT-IN, and Trigonox V388, which are positioned for different reactivity and application requirements within the same general MEKP family. Butanox M-60 offers 10% higher active oxygen for a faster medium-reactive cure, Butanox LPT-IN is formulated for extra-long gel time in filament winding and large-part production, and Trigonox V388 is developed for general purpose GRP and non-GRP curing outside of marine-specific applications.
Selecting between these grades depends on target gel time, application type, and whether marine osmosis resistance is a specific requirement. Our team can help match the correct MEKP grade to your resin system and end-use application.
Where to Source This Product
Thousands Chemicals supplies Butanox M-50 and related organic peroxide products through our digital B2B marketplace, with supply chain resource support for fabricators sourcing curing systems for gelcoat, laminating, and marine applications. Peroxide handling and classification are commonly referenced against guidelines published by ASTM International. Our team can help confirm packaging, lead times, and technical documentation for your target application and order volume.
Documentation We Can Provide
For buyers evaluating this MEKP for a new gelcoat, laminating, or marine project, our team can help arrange the current technical data sheet and safety data sheet. Having this documentation in hand before finalizing a curing schedule can help avoid delays later in your qualification or approval process.
Frequently Asked Questions About Butanox M-50
What is the active oxygen content of Butanox M-50?
It has a total active oxygen content of 8.8 to 9.0%, with a density of 1.180 g/cm³ and viscosity of 24 mPa.s at 20°C.
Is this MEKP suitable for marine applications?
Yes, its guaranteed low water content and absence of polar compounds make it very suitable in GRP products for marine applications.
What resins is it compatible with?
It is used for curing unsaturated polyester resins, including gelcoat resins, laminating resins, lacquers, and castings, in the presence of a cobalt accelerator.
Can you provide technical documentation and bulk pricing?
Yes, technical data sheets and SDS documentation are available on request, and our team can provide bulk pricing and lead times based on your target volume and delivery location.
Get a Quote for Butanox M-50
Contact our team for a quote, technical data sheet, or SDS for this MEKP. We support bulk supply and global shipping for fabricators sourcing consistent, medium-reactive curing systems for gelcoat, laminating, and marine production.
