Hychem GP-T — General purpose epoxy binder for concrete repairs & floor resurfacing

• Epoxy toppings can exert considerable shear forces on the underlying concrete substrate due to differential thermal movements. It is most important that the concrete surface is adequately prepared. The cement paste layer and any existing surface coatings already in existence need to be removed. This is best carried out using captive shotblasting, grinding or scarifying.
• The resultant surface should have a minimum tensile strength of 1.5 MPa and a minimum compressive strength of 25 MPa.
• Prior washing with a caustic soda solution may be required for surfaces contaminated with animal or vegetable fats. Solvent washes (degreasers) may need to be used to remove petroleum oils and stains.

• In a clean container, mix the HYCHEM GPT liquid components (Resin & Hardener @ 2:1) together using a helical mixer at a speed of 500 rpm until the mix becomes homogenous (1–2 minutes).
• Add HYCHEM aggregates at a ratio of 1:1 (Filler : GPT) to 3:1 by volume to the mix gradually whilst continuing to mix.
• Move the mixer around from side to side and top to bottom and scrape the sides of the mixing vessel to ensure thorough mixing.

The correct application technique is dependent on the intended use of the product.

GROUTING: HYCHEM SL quartz aggregate is added to the already mixed binder at a mix ratio of between 1:1to 3:1 by volume dependant on the size of the aperture to be grouted. Additional coarse quartz may be added for large gaps capable of absorbing the thicker, higher viscosity mix.

CONCRETE RESURFACING: Damaged concrete with or without exposed aggregate can be resurfaced by mixing 1-2 Kg of SL aggregate with 1 litre of GPT binder and applying it across the surface with a flat trowel. This application is often referred to as an epoxy “scratch coat” and is a common technique used prior to the application of an epoxy paint coat.

CONCRETE RE-LEVELLING: When floors need to be re-levelled to provide adequate fluid flow to drains a considerable depth of epoxy mortar needs to be used. For this purpose a dry mix of aggregate at a ratio of approximately 8-10 parts quartz to 1 part resin/hardener combination containing a coarse 2-3mm pebble is recommended. Prime the surface first before installation of the sub-fill mix and allow to cure. Once cured, a heavy seal coat of HYCHEM GPT needs to be applied prior to again topping this time with a chemically resistant system such as the HYCHEM E300 Epoxy Mortar.

ANTI-SLIP TOPPING: A fluid mix of resin & aggregate is spread over the surface and then broadcast with an appropriate anti-slip aggregate to produce the desired surface profile. After cure, excess dry aggregate is removed and the surface is sealed with HYCHEM GPT containing a suitable pigment additive.

When the topping has cured, locate all expansion joints, saw cut as necessary and fill with a suitable joint sealant such as HYFLEX NS.

In reference to anti-slip aggregates, be aware that quartz will crush under heavy traffic and consideration should always be given to using either bauxite or aluminium oxide aggregates as substitutes. Both these products will increase the life span, durability and performance of your ant-slip surface finish.

CLEAN UP: Xylene can be used for cleaning tools and equipment before the mixed compound begins to hardened.

1 litre of binder with 1 litre of quartz makes a total of 1.6 litres of mortar 1 litre of binder with 3 litres of quartz makes a total of 3 litres of mortar 1 litre of binder with 5 litres of quartz makes a total of 4 litres of mortar

PACKAGING: Available in 60 litre & 600 litre kits.

SHELF LIFE: 12 months from date of manufacture, stored under shelter in a cool dry place at 25° C in original un-opened container.

To minimise an unsatisfactory cure the following indicative application conditions should be observed with respect to temperature and humidity levels.

• 21° C and less than 85% humidity
• 10° C and less than 75% humidity

Chemical spillage of acids and sanitizing agents may attack the pigments used in the coating and result in discolouration.

Different epoxy products vary in their resistance to chemicals. Always ensure that the correct product is chosen for the service environment to be encountered. If in doubt contact your Hychem representative or the Hychem technical department for advice.