Description
Mapei Mapesil LM Natural Stone Silicone
– Available as Individual Cartridges and Boxes of 12
– 310ml Cartridges
Mapei Mapesil LM Natural Stone Silicone is a neutral pure silicone sealant
ideal for natural stone. It is solvent-free and mould-resistant sealant with
BioBlock® technology for stone with movements of up to 25%.
ADVANTAGES:
• Does not stain, ideal for sealing stone
• Mould-resistant (BioBlock® technology)
• Seals remain stable over the years
• Solvent-free, odourless
• Wide range of certification
• Suitable for external facades
• High bond strength
• Wide range of colours
TECHNICAL DATA:
• Movement in service: 25%.
• Modulus of elasticity at 100% elongation: 0.35 N/mm².
• Shore A hardness: 21.
• Workability time: 15 minutes.
• Colours: 700 transparent, 100 white, 110 grey, 111 grey, 112 grey, 113 cement
grey, 114 grey, 120 black, 130 jasmine, 132 beige
• EMICODE: EC1 Plus – very low emission.
• Application: extrusion gun.
• Consumption: 3.1 linear metres per 310 ml cartridge (10×10 mm section).
• Packaging: 310 ml cartridges.
WHERE TO USE:
Mapei Mapesil LM Natural Stone Silicone is a solvent-free sealant with a low
modulus of elasticity specifically formulated for sealing all materials sensitive
to acids and plasticising agents, marble, granite, sandstone and quartz due to its
chemical nature which deters surface bleeding or the migration of plasticising
agents which would otherwise stain the substrate.
The chemical characteristics of the product also make it perfectly suitable for
particularly delicate materials such as bricks, cellular concrete and varnished or
enamelled wood.
Mapei Mapesil LM Natural Stone Silicone generally forms an excellent bond on non-
absorbent substrates too, such as glass, ceramic, clinker, enamelled surfaces,
water and solvent-based varnish, metals in general and on various types of plastic.
It is also suitable for contact with absorbent mineral substrates such as concrete,
render and fibre-cement.
This product generally forms a good bond on the above substrates even if a primer
is not applied beforehand (contact the MAPEI Technical Services Department before).
Performs well in treated water typically found in swimming pools.
APPLICATION EXAMPLES
Thanks to the low modulus of elasticity of Mapesil LM, it is suitable for sealing
internal and external fillet and expansion joints, including those subject to high
levels of movement when in service, between:
▪ pre-fabricated panels;
▪ window/door fittings and wall surrounds;
▪ pipe-work and vertical walls;
▪ similar and/or different types of coating materials.
It is also suitable for sealing joints in floors with limited pedestrian traffic.
TECHNICAL CHARACTERISTICS
Mapei Mapesil LM Natural Stone Silicone is a one-component, solvent-free, neutral-
cure silicone sealant which does not emit unpleasant odours, available in the form
of a thixotropic paste. It is easy to apply on vertical and horizontal surfaces and
cures at room temperature through the humidity present in the air to form a
flexible sealant.
Seals made using Mapei Mapesil LM Natural Stone Silicone are extremely stable over
time, even when exposed to inclement weather, industrial environments, temperature
variations or water.
The product remains flexible over a temperature range of between -40°C and +150°C.
Mapei Mapesil LM Natural Stone Silicone delays the formation of surface mould.
Mapei Mapesil LM Natural Stone Silicone generally offers good resistance to
chemical agents. However, because of the wide range of products and service
conditions, if in doubt carry out preliminary tests beforehand.
Mapei Mapesil LM Natural Stone Silicone bonds perfectly to most types of substrate
used in the building industry without applying a primer beforehand (glass, ceramic,
marble, aluminium, zinc-plated sheet metal, concrete, stainless steel and PVC).
Primer FD must be applied beforehand in the case of prolonged immersion in water.
If in doubt, please contact the MAPEI Technical Services Department or carry out
preliminary tests beforehand.
Mapei Mapesil LM Natural Stone Silicone is particularly suitable for surfaces
sensitive to acids on which conventional neutral or acid sealants normally provoke
changes in colour or staining of the substrate.
Mapei Mapesil LM Natural Stone Silicone complies with EN 15651-1 norm (“Sealants
for internal and external façade elements”) with performance rating F-EXT-INT-CC,
with EN 15651-2 norm (“Sealants for glazing”) type G-CC, with EN 15651-3 norm
(“Sealants for joints in sanitary areas”) type XS1 and EN 15651-4 norm (“Sealants
for pedestrian walkaways”) with performance rating PW-EXT-INT-CC.
RECOMMENDATIONS
Do not apply Mapei Mapesil LM Natural Stone Silicone on rubber, heavily-plasticised
plastics or bitumen. The oil and plasticising agents in the substrate may migrate
to the surface and compromise the bond or penetrate into the sealant leading to a
variation in colour and mechanical characteristics.
▪ When Mapei Mapesil LM Natural Stone Silicone is constantly immersed in treated
water typically found in swimming pools its physical-mechanics may be affected
prematurely. Given the wide range of products used to treat water and the
actual quantities employed, its suitability over long periods may only be
guaranteed following specific laboratory testing.
▪ Do not use Mapei Mapesil LM Natural Stone Silicone for sealing floors subject to
intense traffic (use Mapeflex PU45 FT or Mapeflex E-PU21 SL).
▪ Under certain conditions Mapei Mapesil LM Natural Stone Silicone may have a
water-repellent effect along the edges of joints. This effect is only noticeable
when surfaces are wet and is invisible when the same surfaces are dry. This
phenomenon, however, has no effect on the product’s performance characteristics.
▪ Do not use Primer FD when sealing stone or marble.
APPLICATION PROCEDURE
Preparing Joints
Surfaces to be sealed must be solid with no dust or loose parts and free of all
traces of oil, grease, wax, old paintwork and rust.
In order to perform correctly, the sealant must be able to expand and contract
freely once it has been applied in the joint.
It is important, therefore, that:
▪ it only bonds perfectly to the side walls of the joint and not to the bottom;
▪ the width of the joint is calculated correctly so that the product does not expand more than 25% of the initial width of the joint when in service;
Also, to protect the substrate from staining, apply masking tape along the edges of
the joint before extruding Mapei Mapesil LM Natural Stone Silicone.
Regulate the depth of the joint to avoid Mapei Mapesil LM Natural Stone Silicone
sticking to the bottom by inserting Mapefoam polyethylene foam cord in the joint.
Application of Primer FD
If a coat of Primer FD is required, apply the product with a small brush where
required, leave it to dry for a few minutes so that the solvent evaporates and then
apply Mapei Mapesil LM Natural Stone Silicone.
Application of Mapesil LM
Mapei Mapesil LM Natural Stone Silicone is available in 310 ml cartridges. Cut the
tip of the cartridge near the thread and screw on the nozzle. Trim the tip of the
nozzle at 45° according to the width of joint required and insert the cartridge
into a suitable extrusion gun.
Finish the surface of Mapei Mapesil LM Natural Stone Silicone with a suitable damp
tool or a tool dipped preferably in soapy water before the skin forms on the
surface.
Curing
When Mapei Mapesil LM Natural Stone Silicone is exposed to the air, the surrounding
humidity sets off the cure reaction and the sealant becomes flexible.
The surrounding temperature only has a small impact on the cure rate of Mapesil LM,
while the level of humidity in the surrounding air has the most influence. We
highly recommend that the product is never applied if the temperature is below 0°C.
CLEANING
Traces of partially cured Mapei Mapesil LM Natural Stone Silicone may be removed
from tools and the surface of the substrate with common solvents such as ethyl
acetate, benzene or toluene. Once the product has completely cured, the silicone
rubber may only be removed mechanically.
CONSUMPTION
• Joint Size 5mm Width x 5mm Depth – 12m per Cartridge
• Joint Size 5mm Width x10mm Depth – 6m per Cartridge
• Joint Size 10mm Width x10mm Depth – 3m per Cartridge
• Joint Size 15mm Width x10mm Depth – 2m per Cartridge
• Joint Size 20mm Width x10mm Depth – 1.5m per Cartridge
• Joint Size 25mm Width x10mm Depth – 1.25m per Cartridge
• Joint Size 30mm Width x15mm Depth – 0.7m per Cartridge
• Joint Size 40mm Width x20mm Depth – 0.4m per Cartridge
STORAGE
Mapei Mapesil LM Natural Stone Silicone can be stored for 18 months in a dry cool
place in original cartridges.
SAFETY INSTRUCTIONS
Instructions for the safe use of our products can be found on the latest version of
the Safety Data Sheet, available from the Mapei website www.mapei.com.
