MCOR 4911 | mFlex Rapid Rbbr

MCOR 4911 (mFlex Rapid Rbbr) is a high durometer, 100% solids, applied urethane-acrylate epoxy hybrid flexible polymer for quick return-to-service/emergency “cold” applied rubberizing. This new generation of urethane-acrylate epoxy hybrid repair sealants undergo similar development of properties to (cold) vulcanizing which will produce higher strengths; in addition, higher moisture tolerance, increased UV resistance, better surface acceptance and adhesion, more stable and longer lasting shelf life without the concern of isocyanates.

The mFlex Rapid Rbbr is a two component high performance elastomer specifically designed for fast repair, rebuilding, and coating applications of industrial flexible need areas. Because of its curing system and high performance properties, MCOR 4911 provides flexible solutions for emergencies requiring rapid development of properties with extraordinary sealed tolerances to chemicals, wear, abrasion, and degradation while exhibiting strength and robust industrial-grade performance.





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  • Rapid curing, rubberized repair, rebuilding and coating
  • Emergency repairs of rubber and other flexible components
  • Conveyor belts
  • Quick repairs on cracks and scores of tire sidewalls on heavy duty trucks
  • Fast repair of worn gasket seals and rubber rollers
  • Cold curing alternative to vulcanized rubber repairs
  • Hard durometer castable rubber


  • Isocyanate-free, no VOCs
  • Rapid curing, quick return-to-service
  • “Cold” fast curing alternative to vulcanized rubber
  • Excellent UV resistance
  • Terrific adhesion
  • Unique ability to level and hang (both horizontal levelling and vertical/overhead grade)
  • 100% solids
  • 150% elongation
  • Abrasion and wear tolerance
  • Excellent chemical resistance
  • Terrific impact and vibration tolerances

Kit Offerings

1 Kilo Kit (2 x 500g, BLK)
2 x 375g, MCOR 4911 Part-A, Black
2 x 275g, MCOR 4911 Part-B

Color availability:

  • Black (BLK)

The volume capacity of a 1 kg of mixed mFlex MD Vertical Elastomer is 927 cm3.

mFlex Rapid Rbbr as a pour or cast in place repair sealant, material can fill spaces/cracks as thin as 800 microns (1/32”). As a repair coating or patch, can be applied at 0.25mm (10mils) min. to 1.25cm (1/2 inch) max./coat.

mFlex Rapid Rbbr is a 100% solids polymer that will not shrink.  0.93 m2/kg. at 1mm DFT (39.3 ft2/kg at 10 mils DFT). Actual coverage will depend on surface conditions and irregularities.


Rubber repair and sealant

MCOR 4911 | mFlex Rapid Rbbr will:

  • Gel and cure quickly for a rapid return to service
  • Flow and settle for horizontal repairs, while creating a gel window for vertical/overhead repair needs
  • Cure with hard durometer and high strengths

MCOR 4911 | mFlex Rapid Rbbr is:

mFlex Rapid Rbbr is specifically designed to undergo a rapid development of properties. The curing system allows for quick gel-times, fast curing, and a rapid return-to-service, offering the field elastomeric emergency repairs and users a quick curing rubberized coating, casting and rebuilding solution for flexible components or areas requiring elongation.

The advanced curing system of the mFlex Rapid Rbbr provides unique characteristics of both fluidity and paste development in order to assist users with leveling repairs and also vertical repairs. This happens during its curing schedule, whereas first the material will be fluid in order to settle or cast into areas or forms, then after setting for a short period of time, the material will offer a window to build, hang, and apply in paste-grade nature, both vertical and overhead.

mFlex Rapid Rbbr through an advanced crosslinking system similar to (cold) vulcanizing; a chemical process for converting polymers into more durable materials by the addition of elements, curatives, and other proprietary ingredients produces high strengths. Formulated for sealing and resisting industrial attack of chemicals, corrosives, abrasion and wear. These additives modify the polymer by forming cross-links (bridges) between individual polymer chains. The material is also designed to tolerate weathering elements, UV, and other degradation or constants