Why It Matters
Protective primers must stop underfilm corrosion via active inhibition (passivation) and/or barrier (platy fillers extending the ionic diffusion path)
Solution Approach
Protective primers must stop underfilm corrosion via active inhibition (passivation) and/or barrier (platy fillers extending the ionic diffusion path) RawSource supplies the base chemicals that go into these programs. We can help with product selection, grade matching, and sourcing from multiple origins for supply security.
Typical Formulation Workflow
1
System & Substrate Assessment
Define the binder system (waterborne, solventborne, UV, powder), substrate, cure, and the VOC, durability, and appearance targets.
2
Additive & Resin Selection
Match resins, pigments and fillers, dispersants, rheology modifiers, defoamers, or biocides to the formulation and compatibility window.
3
Lab Let-Down & Optimization
Dial in loading and addition order through lab let-downs, checking dispersion, rheology, film properties, and storage stability.
4
Application & Performance Testing
Validate on the real application method and substrate, tracking gloss, adhesion, sag, cure, and weathering before scale-up.
Recommended Chemistries (3)
Barium sulfate (barite)
CAS 7727-43-7
Mineral Fillers & Pigments
Color / Pigmentation
1564 (BARIUM SULFATE) · Class Dense inert extender that increases film density and tortuosity, lengthening the diffusion path for water and ions reaching the steel — a barrier (not active-inhibition) contribution
Physical Description: Barium sulfate appears as white or yellowish od… Appearance: Fine, heavy powder or polymorphous crystals Odor: Odorless
Full Details
Mica
CAS 12001-26-2
Mineral Fillers & Pigments
Thickening / Rheology
Platy lamellar filler that orients parallel to the substrate, building an overlapping barrier that impedes moisture/oxygen permeation to the metal
Melting Point: 1500 °C Density: 2.6 to 3.2 Solubility: Insoluble
Full Details
Talc
CAS 14807-96-6
Mineral Fillers & Pigments
Conditioning
Lamellar magnesium-silicate platelets reinforce the film and extend the permeation path, supporting barrier-type underfilm corrosion resistance
Melting Point: 927–982 °C Density: 2.7 to 2.8 Solubility: < 1 mg/mL at 21 °C
Full Details