Product Overview

MC-Nafuplan EL addresses the critical waterproofing and movement accommodation requirement at concrete joints — the most vulnerable locations in any concrete structure for water ingress, contaminant penetration, and structural deterioration. In reinforced concrete construction, joints are intentional or unintentional discontinuities in the concrete: expansion joints (designed 20 to 30 mm gaps at 20 to 30 metre intervals to accommodate thermal expansion and contraction), construction joints (formed at pour-to-pour interfaces in continuous structures), perimeter joints (the gap between two different structure elements like a basement wall and the ground slab), and saw-cut contraction joints in pavements and industrial floors — all of these joints must be sealed to prevent water and contaminant ingress while accommodating the joint movement without the sealant failing in tension, compression, or shear. The elastic polyurethane chemistry of MC-Nafuplan EL (moisture-curing single-component polyurethane, reacting with atmospheric moisture to cross-link into a tough, elastomeric polymer) provides the three key properties required in a structural joint sealant: (1) high elongation (200 to 400 percent) for accommodation of joint movement without tearing; (2) strong adhesion to concrete, mortar, brick, and steel substrates without a separate primer in most cases; (3) weather resistance — UV stability, ozone resistance, and temperature resistance from -40 degrees Celsius to +90 degrees Celsius — for outdoor joint sealing on facades, podium slabs, and bridge decks in the extreme Delhi NCR climate (summer 45 degrees Celsius, monsoon rain, occasional winter frost). The single-component moisture-curing chemistry of MC-Nafuplan EL eliminates the pot life management and mixing ratio control required by two-component PU sealants — particularly important for joint sealing projects with many short individual joint lengths (where a two-component sealant would require constant small-batch mixing with high wastage) or in remote site locations where the consistency of two-component mixing cannot be reliably controlled. Space Arc Engineering supplies MC-Nafuplan EL for building joint sealing, parking structure maintenance, bridge joint repair, and industrial floor joint sealing in Ghaziabad, Noida, Delhi, and Uttar Pradesh.

Applications

• Expansion joint sealing in multi-storey residential and commercial buildings — sealing of 20 to 30 mm wide expansion joints in multi-storey residential and commercial buildings (apartments, offices, hotels, malls) in Delhi NCR where the joint width is designed to accommodate 3 to 6 mm of thermal movement annually (10 to 15 percent of joint width) over the full building height including external facades, internal corridor joints, roof slab joints, and basement level joints; MC-Nafuplan EL is applied by gun from 600 ml sausage pack or 400 ml cartridge into a properly prepared joint (joint faces cleaned of dust, oil, and loose material; joint depth-to-width ratio 1:2 achieved with PE backer rod at the correct depth) to produce a concave-tooled sealant bed with adhesion to both joint faces and movement capability of plus or minus 25 percent of joint width (the ISO 11600 Class F25 movement accommodation standard for facade joint sealants); the paintable surface of cured MC-Nafuplan EL allows colour-matching with the adjacent facade coating for architecturally finished buildings
• Parking deck and podium slab joint sealing against water and chloride penetration — sealing of saw-cut contraction joints, construction joints, and perimeter edge joints in parking deck slabs, podium slab waterproofing systems, and podium landscape areas of multi-storey buildings in Delhi NCR where the joint must simultaneously accommodate deck slab thermal and deflection movement and provide waterproofing against rainwater and vehicle-tracked-in chloride solution penetrating to the concrete structure below; joint sealing on parking decks is a critical maintenance activity because water and chloride ingress through unsealed joints (or joints with degraded sealant) is the primary cause of the reinforcement corrosion and spalling damage that makes parking structure concrete repair one of the most common and expensive maintenance activities in the 5 to 25 year building age range in Noida, Gurgaon, and Delhi NCR
• Bridge expansion joint re-sealing and road median and kerb joint sealing on national and state highways in Uttar Pradesh and Delhi NCR — re-sealing of failed or deteriorated expansion joint sealant in bridge deck expansion joints, approach slab joints, and road pavement transverse contraction joints on NHAI national highways, PWD state highways, and NMMC urban road pavements in UP and NCR; joint sealant in road and bridge applications is subjected to heavy traffic wheel loads (causing joint compression up to 50 percent at the joint) and vehicle acceleration and braking forces (causing joint shear) in addition to the thermal movement; MC-Nafuplan EL high elongation (200 to 400 percent) and tear resistance provide the durability required for road joint applications without the cracking and tearing that afflicts standard acrylic or polysulfide sealants under repeated traffic loading

Key Advantages

• Single-component moisture-curing format for simplified application without pot life time pressure or two-component mixing errors — MC-Nafuplan EL as a single-component sealant can be applied directly from the gun (no mixing) and cures over 24 to 72 hours by reaction with atmospheric moisture, with no pot life constraint during application; this eliminates the primary quality risk of two-component PU sealants — incorrect mixing ratio causing partial cure or full failure of the sealant — and the pot life time pressure (typically 30 to 60 minutes for two-component PU) that causes application quality issues when the sealant starts gelling in the mixing nozzle during a long joint run or when the applicator is interrupted; the single-component format is also more suitable for maintenance applications with many short joint lengths (individual joints of 0.5 to 2.0 metres) that are better served by the flexibility of a single-component gun than by large-batch two-component mixing
• Paintable surface for colour-matching with adjacent facade or floor finishes on architectural applications — cured MC-Nafuplan EL has a surface that accepts standard exterior acrylic or polyurethane-acrylic facade paint and floor coatings, allowing the sealed joint to be painted to match the adjacent concrete, render, or coating colour; this paintability is important for architectural facade applications on premium residential and commercial buildings in Delhi NCR where an unpainted grey or black sealant joint would be visually unacceptable against a white or pastel-coloured exterior paint finish; the painted joint also receives additional UV protection from the paint layer, extending the maintenance-free service life of the sealant in the intense UV radiation of the Delhi NCR summer (UV index 8 to 11 in May to July)