Silcor® 990MP

Pure polyurea, spray-applied waterproofing membrane

Product Description

Two-part, fast-curing, pure polyurea, spray-applied elastomeric coating.

It provides a premium quality, high build, long life protective coating to concrete and metal substrates on major civil, infrastructure and commercial construction projects. Formulated using the latest polyurea technology, it forms an impenetrable barrier that is resistant to water, chemicals, sewage and wear.


Silcor® 990MP contains no TDI, MOCA, bitumen or tar-based compounds. Being polyurea, it has good resistance to humidity during application and forms a tough, bubble-free, impermeable coating.

Silcor 990MP is a simple 100:100 by volume mix ratio system that applies with good flow out and rapid cure, resulting in a smooth, even coating finish that can be walked on in seconds.

The cured elastomer has high substrate adhesion plus excellent resistance to tear, puncture, chemicals, water and abrasion. Unlike rigid coating materials such as epoxies, vinyl ester, etc., Silcor 990MP resists post-application reflection cracking in concrete substrates.

  • Simple application — fast cure 
  • Potable water certified
  • Suitable for continuous immersion
  • Long-life — permanently flexible
  • Abrasion and chemical resistance
  • Total adhesion — no water tracking
  • Resistant to sewage gases — H2S, H2SO4 etc Resists reflection cracking in concrete
  • Suitable for continuous immersion in demineralised, fresh and salt waters plus desalination permea


Silcor 990MP elastomer system is ideally suited for most areas of protective coating, lining and waterproofing in civil and commercial applications.

Used as a waterproof and highly chemical-resistant barrier on:

  • Sewage and water treatment plants
  • Desalination plants
  • Potable water containment
  • Chlorinated swimming lagoons
  • Tunnels 
  • Bridge-decks
  • Chemical process facilities

It provides lasting protection to plant room floors, chemical storage and secondary containment areas.

Silcor 990MP is compatible with most stable, suitably-prepared rigid substrates, including concrete, steel, aluminium, shotcrete, brick, block, render and fibre cement sheet.

Application Equipment

Silcor 990MP is designed for application through high-pressure, plural component spray equipment capable of processing polyurea coatings.

Suitable equipment includes Graco Reactor E-XP2 or H-XP2 machinery fitted with high output heaters, heated lines and Graco Fusion Air Purge or Fusion CS impingement mix spray guns. Equipment should also be fitted with a drum mounted agitator for the polyamine component, material recirculation and drum mounted desiccant driers on both the polyamine and isocyanate components.

Silcor 990MP polyamine component must be agitated before and during use. The isocyanate component does not require agitation.

Typical machine spray settings required for Silcor 990MP application are:

Material Temperature 20°C to 25°C
Main Heater Temperature 60°C to 70°C
Line Heater Temperature 60°C to 70°C
Spray Pressure 2500 to 2800 psi

Round pattern spray gun mix chambers will minimise overspray produced considerably.

Application Guidelines


Substrates must be clean, dry, free of curing compounds, oil, grease, solvent or other contaminants. Moisture content of concrete must be below 5%.  Concrete should be cured 28 days and render 7 days.

Environmental Conditions

The following conditions must be achieved prior to and maintained during Silcor 990MP application

Ambient Temperature 4°C to 45°C
Substrate Temperature 5°C to 60°C
Relative Humidity 85% maximum
Dew Point 3°C below substrate
Approximate Wind Speed 10 knots maximum


Apply product in one or more passes to the required dry film thickness. Typically a DFT of 2.0mm to 3.5mm is required for protective coating/lining applications. Specified minimum DFT required will be detailed in our GCP project specific AMS.


Where colour stability is required in sun-exposed applications, apply our aliphatic, UV-stable topcoat, Silcor Top Coat 80, where colour stable protection and a non-slip finish is required.


Small area < 1m² may be repaired by reapplication of Silcor 780HI-LP as detailed in the relevant AMS. In space restricted areas where spray application is not practical, Silcor 580 membrane systems (with Silcor Top Coat 80 finish where UV stability or non-slip finishes are required) can be used, in consultation with your local GCP representative.

Surface Preparation

See project-specific Application Method Statement (AMS) for detailed requirements. Generally, for concrete substrates use wet, wet-abrasive or dry-abrasive blasting to remove laitance, etc.

Patch concrete defects using high strength (minimum 25MPa), non-shrink, repair mortar and allow to cure fully.

Fill all joints, cracks, gaps and form angle fillets in internal corners or penetrations with Silcor LM PU sealant.

Blast or mechanically clean steel substrates to a 90μm surface profile. Prime with Silcor Primer BW F100 at 0.25kg / m2 or Silcor Primer BS at 0.15kg / m2dependent on substrate condition. Allow to dry approximately 0.5 to 3 hours depending on ambient conditions and surface porosity.


1.1kg (1 litre) of Silcor 990MP system provides coverage of 1m2 at 1.0mm coating thickness. Allow for processing losses, over spray, etc – typically 10% or greater depending on surface and ambient conditions.

Typical Properties

Mix ratio - polyamine : Iso (by volume) 100 : 100 -
Polyamine viscosity (@ 25ºC) 400 - 1000 mPa.s ASTM D2196
Polyamine specific gravity (@ 25ºC) 1.02g / mL ASTM D1475
Isocyanate viscosity (@ 25ºC) 400 - 1000 mPa.s ASTM D2196
Isocyanate specific gravity (@ 25ºC) 1.12g / mL ASTM D1475
Gel time (@ 25ºC) 4 seconds -
Tack free time (@ 25ºC) 20 seconds -
% solids (v/v) 100 % -
Recommended applied thickness 2.0 - 3.5mm -
Return to service
- Light foot traffic
- Heavy foot traffic
- Continuous water immersion
- Paving, topping, backfill, landscaping
- Potable water, chemical or abrasion exposure

3 minutes
1 hour
4 hours
8 hours
7 days

Shore a hardness (minimum) 90 ± 5 ASTM D2240
Tensile strength (minimum) >16 MPa ASTM D412
Elongation (minimum) 300% ASTM D412
Tear strength (minimum) 58.8N / mm ASTM D412
Taber abrasion resistance (maximum) 50 mg ASTM D4060
Crack bridging Pass ASTM C836
Pull-off strength (minimum)
- Inter-coat adhesion
- Concrete (primed) (substrate failure occurred)
- Steel (90μm blast profile)

> 2.0 MPa
> 2.0 MPa
> 3.0 MPa
ASTM D4541
Potable water certification Certified BS6920:2000

Product Risk

The Silcor 990MP system is not intended for use by other than experienced operators. The data herein requires experience and knowledge to attain correct interpretation and outcome. The user must undertake all relevant tests to determine the suitability for the intended application, as such determination of fitness of purpose for product use, is the sole responsibility of the purchaser.


Silcor 990MP Polyamine 18.5kg & 200kg drums
Silcor 990MP Isocyanate 20kg & 210kg drums

Clean Up

Clean-up liquid leakage or spills before hardening occurs using solvents such as xylene, MEK or acetone.


The Silcor 990MP polyamine and isocyanate components should be stored <25°C, <60% RH. Drums must remain tightly sealed against moisture ingress. Under these storage conditions these materials will have a shelf life of 12 months. Storage at temperatures other than detailed can result in degradation and crystallisation in the drum, rendering the materials unusable. Ingress of humidity or water into the drums during storage or use will also make product unusable.


Refer to Silcor 990MP Material Safety Data Sheet (MSDS).

Operators must have full awareness of the material safety requirements before any work is undertaken. Silcor 990MP polyamine component is a mild irritant. Avoid contact with skin or eyes.

Silcor 990MP isocyanate component contains Methylenebisphenyl Diisocyanate (MDI). It is an irritant and allergic sensitiser to skin and respiratory systems. Avoid contact with skin or eyes. Avoid breathing vapour or spray aerosol.

Silcor 990MP system spray application must occur in areas with adequate ventilation. Suitable organic vapour respirators or air-fed hoods must be worn during spray operations. Other required PPE includes butyl or nitrile gloves, safety goggles or full-face shield, coveralls and chemical-resistant safety boots.

Health and Safety

In case of spills and accidents, refer to the MSDS of the products or when in doubt contact your local GCP representative.

Always wear protective clothing, gloves and protective goggles when handling chemical products.

For full information, consult the relevant MSDS.

Project Specification

GCP offers a comprehensive package of quality and proven systems to meet different project and application needs. Contact your local GCP representative for further information. | Thailand customer service: 66 2 030 9700

We hope the information here will be helpful. It is based on data and knowledge considered to be true and accurate, and is offered for consideration, investigation and verification by the user, but we do not warrant the results to be obtained. Please read all statements, recommendations, and suggestions in conjunction with our conditions of sale, which apply to all goods supplied by us. No statement, recommendation, or suggestion is intended for any use that would infringe any patent, copyright, or other third party right.

Silcor is a trademark, which may be registered in the United States and/or other countries, of GCP Applied Technologies, Inc. This trademark list has been compiled using available published information as of the publication date and may not accurately reflect current trademark ownership or status.

© Copyright 2017 GCP Applied Technologies, Inc. All rights reserved.

GCP Applied Technologies Inc., 62 Whittemore Avenue, Cambridge, MA 02140, USA.

GCP Applied Technologies Holdings (Thailand) Limited, 848 Moo 2 Bangpoo Industrial-Estate (North),  Phraksa Mai, Muang,  10280 SAMUTPRAKARN, Bangkok.

This document is only current as of the last updated date stated below and is valid only for use in Thailand. It is important that you always refer to the currently available information at the URL below to provide the most current product information at the time of use. Additional literature such as Contractor Manuals, Technical Bulletins, Detail Drawings and detailing recommendations and other relevant documents are also available on Information found on other websites must not be relied upon, as they may not be up-to-date or applicable to the conditions in your location and we do not accept any responsibility for their content. If there are any conflicts or if you need more information, please contact GCP Customer Service.

Last Updated: 2020-03-20