Next generation, phthalate free, closed cell, 1-component high performance hydrophobic, hydroactive, flexible polyurethane injection grouts for waterproofing leaking joints and cracks

Product Description

In its uncured form, HA FLEX™ LV AF /Flex SLV AF are white or yellow, non-flammable liquids without phthalate plasticisers. HA Flex LV AF /Flex SLV AF are next generation 1-component injection resins with improved waterproofing performance. When they come in contact with water, the grout expands and quickly (depending on temperature and the amount of accelerator HA Flex Cat AF used) cures to a tough, flexible, closed-cell polyurethane foam that is essentially unaffected by corrosive environments.

Field of Application

HA Flex LV AF /Flex SLV AF

  • Designed for grouting joints or stopping water leaks in concrete structures, which are subject to settlement and movement.
  • Used for protective waterproofing and gap filling around the brush tails of the TBM and for repairing the waterproof gasket.
  • For stopping water leaks through joints between tunnel segments.
  • For injection of the LDPE or HDPE membrane in tunnel constructions.
  • For curtain injections behind tunnel segments.

HA Flex SLV AF (Specific fields of application)

Specifically developed for injection of fine and ultra fine crack and joints.

Joint and Crack Dimensions

  • Always select a resin based on the crack or joint size to be injected.
  • Small cracks will require low or ultra-low viscosity resins to ensure good crack penetration.

As a general recommendation, the following crack dimensions can be used:

HA Flex LV AF cracks > 0.5mm
HA Flex SLV AF cracks < 0.5mm

Product Advantages

  • ADR free transport.
  • Next generation resin with improved waterproofing performance.
  • Improved cell structure of the cured compound resulting in better mechanical properties and durability.
  • Phthalate free resins, REACH compliant.
  • Improved performance at temperatures below 5°C, no crystallisation of HA Flex Cat AF.
  • HA Flex LV AF /Flex SLV AF form a flexible gasket or flexible plug in the joint or crack.
  • Non-flammable, solvent free.
  • Choice of different expansion rates.
  • User friendly: 1 - component product.
  • Controllable reaction times: by using catalyst curing times can be reduced.
  • Cured compound is resistant to most organic solvents, mild acids, alkalis and micro- organisms. (*)

(*) For chemical resistances please contact your GCP representative.


  • Before commencing the injection, consult the Material Safety Data Sheet (MSDS) in order to be familiar with the materials at hand.
  • Always shake the HA Flex Cat AF well before use.

1. Surface Preparation

  • Remove surface contaminants and debris to establish the pattern of the crack or joint. Active leaking cracks larger than 3mm need to be sealed with an approved method.
  • Drill holes of the correct diameter for the selected packer. Drill at an angle of 45°. Preferably the holes should be drilled staggered around the crack to insure good coverage of the crack in case it is not perpendicular to the concrete surface.
  • The depth of the bore should be approximately half of the thickness of the concrete. As a rule of thumb the distance of the drill point from the crack is half the wall thickness.
  • Distance between holes can vary by 15 to 90 cm, depending on the actual situation. •Insert the correctly sized packer into the hole up to 2/3 of its length. Tighten with a wrench or spanner by turning clockwise until sufficient tension has been reached to keep the packer in place during injection.
  • Flush the crack with water before injecting with resin. This will flush out dust, debris and prime the crack for the injection resin and improve penetration of the product into the crack. Water in the crack will activate the resin.

2. Resin and Equipment Preparation

  • Prepare the resin with the predetermined amount of catalyst. Shake HA Flex Cat AF well before use. No reaction with the resin will occur until the resin comes into contact with water.
  • Do not prepare more resin than can be injected within 4 hours after mixing HA Flex Cat AF in the resin. Avoid mixing full drums, it is recommended to batch mix smaller quantities in a separate pail or in the pump reservoir.
  • Protect the resin from water, since this will trigger a reaction in the container used and might cause the resin to harden or foam prematurely within the injection equipment.
  • It is highly recommended to use separate pumps for the water and the resin injection to prevent cross contamination and blockages.
  • The pumps should be thoroughly primed with Washing Agent to lubricate and dry the system before injection. We recommend the use of pneumatic or electric 1- component pumps.

3. Injection

  • Start the injection at the first packer.
  • Start injecting at the lowest pressure setting of the pump. Slowly increase the pressure until the resin begins to flow. Pressures may vary from 14 bars to 200 bars depending on the size of the crack, the thickness of the concrete and the general condition of the concrete.
  • A little leakage of resin through the concrete or crack is useful in showing the extent of resin travel. Large leaks should be plugged with rags, wait for the resin to set, then inject again.
  • During the injection water will first flow from the crack, followed by foaming resin. After this, pure resin will flow from the crack.
  • Stop pumping when the pure resin reaches the next packer.
  • Move to the next packer and repeat the procedure.
  • After injecting through a few of the packers, go back to the first one and re-inject with resin.
  • After the resin injection, water can be re-injected into the ports to cure resin left behind.
  • Let the resin cure thoroughly before removing packers. The resulting holes can be filled with hydraulic cement.
  • When the injection is finished, clean all tools and equipment which have been in contact with the resin with Washing Agent. This should be done within 30 minutes. Never leave the pump filled with resin overnight or for periods beyond 1 shift. Do not use solvents or other cleaning products since they give less positive results and can create hazardous situations.
  • Products should be disposed off according to local legislation.
  • Refer to Material Safety Data Sheet (MSDS) for general recommendations. In case of spills and accidents, refer to the MSDS of the products or when in doubt contact your local GCP representative. Always wear appropriate protective gear for the job at hand according to local guidelines and regulations. We recommend that gloves and protective goggles are worn when handling chemical products. See MSDS for further recommendations.

4. Reactivity

Reactivity HA Flex Cat AF Start Reaction   End Reaction   Expansion
    HA Flex LV AF HA Flex SLV AF HA Flex LV AF HA Flex SLV AF  
At 5°C 1%
Approx. 3’30”
Approx. 2’15”
Approx. 55”

Approx. 1’30”
Approx. 50”
Approx. 8’30”
Approx. 4’00”

Approx. 6.30”
Approx. 3.25’’
Approx. 14V
Approx. 16V
At 15°C 1%
Approx. 2’10”
Approx. 1’25”
Approx. 40”

Approx. 1’10”
Approx. 35”
Approx. 10’50”
Approx. 7’00”
Approx. 3’05”

Approx. 5’10”
Approx. 2’35”
Approx. 14V
Approx. 16V
Approx. 16V
At 25°C 1%
Approx. 1’30”
Approx. 1’05”
Approx. 35”

Approx. 1’00”
Approx. 35”
Approx. 9’00”
Approx. 5’35”
Approx. 2’10”

Approx. 4’30”
Approx. 2’20”
Approx. 14V
Approx. 16V
Approx. 17V
At 30°C 1%
Approx. 1’05”
Approx. 45”
Approx. 25”

Approx. 50”
Approx. 30”
Approx. 7’30”
Approx. 4’40”
Approx. 1’45”

Approx. 4’20”
Approx. 2’00”
Approx. 14V
Approx. 16V
Approx. 17V
At 35°C 1%
Approx. 55”
Approx. 40”
Approx. 20”

Approx. 50”
Approx. 25”
Approx. 6’45”
Approx. 4’00”
Approx. 1’35”

Approx. 3’35”
Approx. 1’45”
Approx. 15V
Approx. 17V
Approx. 18V

HA Flex SLV AF should always be used with a minimum of 2% HA Flex Cat AF.

Technical Data / Properties

Property Value   Norm
Uncured HA Flex LV AF HA Flex SLV AF  
Solids 100% 100% EN ISO 3251
Viscosity at 25°C (mPas) Approx. 550 Approx. 200 EN ISO 3219
Density (kg/dm3) Approx. 1.020 Approx. 1.075 EN ISO 2811
Flash Point (°C) > 132 > 132 EN ISO 2719
HA Flex Cat AF      
Viscosity at 25°C (mPas) Approx. 15   EN ISO 3219
Density (kg/dm3) Approx. 0.950   EN ISO 2811
Flash Point (°C) 105   EN ISO 2719
Density (kg / dm3) Approx. 1.000   EN ISO 1183
Tensile Strength (N / mm2) Approx. 1.2   EN ISO 527
Elongation (%) Approx. 100 Approx. 100 EN ISO 527


HA Flex LV AF /Flex SLV AF

5kg, 25kg or 200kg metal drums

1 Pallet 180 x 5kg drum
24 x 25kg drum
4 x 200kg drum

HA Flex Cat AF

0.25 or 1L plastic bottle or 20kg metal drum

1 box 15 x 0.25L
1 box 16 x 1L
1 Pallet 84 boxes with 0.25L bottles
24 boxes with 1L bottles
24 x 20kg metal drums


HA Flex LV AF Yellow liquid
HA Flex SLV AF Yellow liquid
HA Flex Cat AF Grey transparent liquid


Has to be estimated by the engineer or operator and depends on width and depth of the cracks and voids which need to be injected, and on the expansion rate of the chosen resin.


HA Flex LV AF /Flex SLV AF are sensitive to moisture and should be stored in original containers in a dry area. Storage temperature must be between 5°C and 30°C. Once the packaging has been opened, the useful life of the material is greatly reduced and should be used as soon as possible.

Shelf life: 2 years.


To be ordered separately

  • IP 1C - Manual hand pump.
  • IP 1C - Compact electric airless diaphragm pump.
  • IP 1C - Pro electric airless diaphragm pump.
  • Packers and connectors.

(Please consult the relevant data sheet).

Health and Safety

HA Flex LV AF Flex SLV AF resins are classified as harmful.
HA Flex Cat AF is classified as irritant.

In case of spills and accidents, refer to the Material Safety Data Sheet 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.

gcpat.my | For technical information: asia.enq@gcpat.com

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.

HA and Flex are trademarks, 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.

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GCP Applied Technologies Inc., 2325 Lakeview Parkway, Alpharetta, GA 30009, USA
GCP Applied Technologies (Malaysia) Sdn. Bhd, 7 Lorong CJ 1/1A, Off Jalan Balakong, 43200 Cheras Jaya, Kuala Lumpur, Malaysia
This document is only current as of the last updated date stated below and is valid only for use in Malaysia. 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 www.gcpat.my. 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: 2024-01-23