MC-Bauchemie MC-DUR Putty-MI
A solvent-free epoxy putty from MC-Bauchemie that bonds and cures even underwater, for crack sealing, pointing and marine repair where dry-condition products cannot be used.
What is it?
A two-component, 100 percent solids epoxy putty with a moisture-insensitive amine cure — it hardens on damp, wet or fully submerged concrete and steel.
Where is it used?
Crack and joint sealing in concrete and metal; pointing on marine structures; protective lining and patch repair on tanks, sumps and reservoirs; food and dairy plant surfaces.
Why use it?
Dewatering a sump or waiting out the monsoon is not always possible — Putty-MI cures with good bond strength in dry, moist or underwater conditions and resists corrosion, chemicals and abrasion once set.
How is it applied?
Mix resin and hardener 1:1 by weight for 3-5 minutes, hand-apply with a spatula, trowel or gloved hand within the roughly 50-minute pot life, and finish with a wet-glove rub.
About MC-Bauchemie MC-DUR Putty-MI
MC-DUR Putty-MI answers a repair problem every site engineer knows: the crack that keeps weeping, the sump that cannot be shut down, the tank that has to go back into service before the shutdown window closes. It is a two-component, solvent-free epoxy putty built on a moisture-insensitive amine cure, so it bonds properly even when the substrate is damp, wet, or submerged — a real limitation for ordinary epoxy putties, which need a genuinely dry surface. Mixed 1:1 by weight to a trowel-grade consistency, it suits hand application on crack faces, joints and localised defects, not large-volume voids.
For an authorised MC-Bauchemie distributor working Delhi NCR and pan-India, that matters because it removes the wait-for-dry-weather constraint from most repair work: post-monsoon basement seepage, STP/ETP tank walls accessible only in short shutdown windows, tidal-zone marine pointing, water-retaining structures needing patching without full dewatering. Compliance with FIP 5.1, ASTM C579, ASTM C882 and EN 1542 also gives consultants something concrete to cite in the BOQ.
The technical insight
The “MI” stands for Moisture Insensitive, and the mechanism is the amine-type hardener. Standard epoxy hardeners lose adhesion when a surface-water film blocks the chemical bond from forming; this amine agent tolerates that film and still cures fully. The strength data backs it up: over 20 N/mm² compressive strength inside 24 hours, over 25 N/mm² by day three (ASTM C579), bond strength above 2.5 N/mm² (EN 1542) and slant shear above 10 N/mm² (ASTM C882) — all ahead of ordinary M25-M30 concrete’s tensile capacity, so a stressed joint fails in the parent concrete, not the bond line.
Where it is used
- Sealing cracks in concrete/metal in dry, damp or fully submerged conditions
- Pointing marine structures — jetties, piers, sea walls in the tidal zone
- Protective lining and patch repair inside reservoirs, sumps and RCC tanks
- Repair in potable water plants, breweries, dairies and food-processing units
- Sealing construction/cold joints before a waterproofing coat goes over
- Patching leaking pipe penetrations in basements and STP/ETP tanks in service
- Bedding and pointing around anchor bolts and sleeves exposed to moisture
- Sealing steel-to-concrete interfaces needing corrosion protection
Key advantages
- Cures and bonds fully underwater or on wet substrates — no dewatering first
- Solvent-free, 100% solids — no solvent shrinkage, safer in confined spaces
- High early strength, over 20 N/mm² in 24 hours, shortens downtime
- Bond and slant-shear values exceed concrete’s tensile capacity — failure stays in the substrate
- Good adhesion to concrete, steel and masonry — one material, mixed substrates
- Resists water, corrosion and chemicals once cured — suits effluent and marine exposure
- Trowel consistency holds on vertical/overhead faces without slump
- Tested to FIP 5.1, ASTM C579/882 and EN 1542 — a documented QA/QC basis
Limitations & considerations
- Short pot life, about 50 minutes at 30°C, shorter in summer heat — batch small
- Application stops below +5°C — rarely an NCR issue, relevant in winter
- Built for sealing/pointing, not bulk-fill — large voids need a repair mortar
- UV-sensitive as a pure epoxy — will chalk on exposed facades unless overcoated
- Unforgiving of mix-ratio errors — needs a trained applicator
- Cleaning needs MC-Thinner EP; water-based cleaners cannot be used
Selection & best practice
Concrete must be sound, laitance-free and stripped of oil/curing compound, water-jetted where old coatings or honeycombing exist; steel needs blast-cleaning to SA 2.5 per DIN 55928 part 4. Mix base and hardener 1:1 by weight for 3-5 minutes with a slow paddle mixer (max 600 rpm), place within the pot life by gloved hand, spatula or trowel, and finish with a wet-glove rub. Where a crack is still leaking, run an MC-Injekt polyurethane first to stop the water, then point with Putty-MI.
Specifications
| Chemistry / System | Two-component, solvent-free, moisture-insensitive epoxy resin putty |
| Mixing Ratio | 1:1 by weight (resin : hardener) |
| Mixed Density | 1.55 kg/l at 27°C |
| Pot Life | 50 minutes (100 g mass at 30°C, per FIP 5.1) |
| Compressive Strength | >20 N/mm² at 1 day, >25 N/mm² at 3 days (ASTM C579) |
| Bond Strength | >2.5 N/mm² at 3 days (EN 1542) |
| Slant Shear Strength | >10 N/mm² at 3 days (ASTM C882) |
| Application Temperature | +5°C to +40°C substrate/ambient; +10°C to +40°C material; tensile per FIP 5.14 = concrete failure |
| Pack Size / Colour / Shelf Life | 8 kg kit; grey; 12 months sealed, stored +5°C to +30°C |
Industry use cases
Marine and Port Infrastructure
Pointing and crack sealing on jetty piles, sea walls and breakwaters in the tidal zone, where the substrate is wet at every low tide.
Water and Wastewater Treatment
Patching STP/ETP tank walls and sumps during short shutdown windows, without needing the structure fully drained first.
Food, Beverage and Pharma Plants
Repairing floors and walls in breweries, dairies and meat-processing units that need washdown and mild-chemical resistance.
Basements and Below-Grade Structures
Sealing seepage cracks and construction joints post-monsoon, ahead of a waterproofing coat over the repair.
Industrial Steel-Concrete Interfaces
Sealing joints where anchor bolts or pipe sleeves meet concrete in plants with regular condensation or washdown.
Frequently asked questions
Can it really be applied on a wet or dripping surface, or is “moisture insensitive” marketing?
How is this different from a regular two-component epoxy putty?
What working time do we get in Delhi NCR summer conditions?
Can it be used inside a tank while there is still standing water in it?
What surface prep does steel need before applying it?
What pack size does Space Arc supply?
How we position MC-Bauchemie MC-DUR Putty-MI
Within MC-Bauchemie’s range, Putty-MI sits beside the MC-Injekt line: MC-Injekt EP and 640 are low-viscosity epoxies for pressure-injecting fine dry cracks, while MC-Injekt 2K PU, 1K and FS stop actively flowing water before a crack is sealed. For bulk-volume repair rather than pointing, the ombran cementitious mortar range fits better, with an MC-DUR EPW epoxy topcoat available for a protective finish over the repair. Where a specification calls for another brand, Fosroc’s Nitomortar UA covers similar ground — a solvent-free, two-part epoxy putty that also cures underwater and in tidal zones — a sensible pick on a Fosroc-standardised project; on an otherwise MC-Bauchemie job, Putty-MI keeps repair chemistry under one manufacturer.
Fosroc Nitomortar UA — Fosroc’s Nitomortar UA is a genuine underwater-curing, two-part epoxy repair putty alternative — worth specifying instead when a project is already standardised on Fosroc systems or a consultant has named it directly in the BOQ.
Related Concrete Repair products
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Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.