- Low VOC and low odor for new sealants
- Transfer bonding
- The polymeric MSs very present
- DIFFERENT TYPES OF GLUE STICK SIZING
- Test bench of 14 adhesive mastics
Fix any object on almost any type of material without changing glue: this is the commitment displayed by many adhesive mastics. But do they really keep their promises?
Appeared more than ten years ago, glues-adhesives (or fixing) are more and more used by do-it-yourselfers. High performance, resistant and easy to use, they sometimes replace the assemblies by nails or screws. These products are so-called contact adhesives: simply glue the piece and apply it by compressing it against the support. Most often, the binder (which ensures the adhesion) is synthetic: polyurethane, neoprene, acrylic, MS (Modified Silicone) polymer... It is dissolved in a solvent (alcohol, ketone...) which evaporates or is absorbed by the support. The adhesive mastics are in the form of thick paste, colored or transparent, generally packaged in a cartridge (to be mounted on a gun). They apply in the form of pads or cords. Note that once opened, it is better to use the entire contents of the cartridge, which tends to dry, even if its shelf life is one year after opening (well closed and stored in a room to constant temperature of 20° C). After use, fresh stains and burrs are cleaned with a wet sponge (acrylic glue), acetone or white spirit (neoprene glues, polyurethanes and polymers).
Low VOC and low odor for new sealants
Here we tested the products of manufacturers frequently distributed in DIY superstores (Bostik, Geb, Pattex, Rubson, Sader and Sika). These masticscolle differentiate in the first place by the nature of the binder used.
And each of them has advantages and disadvantages...
Acrylic mastics have little or no volatile organic compounds (VOCs) and little odor. Their application is by simple gluing. After complete drying (at least 48 hours), the mechanical strength of the bonding can reach 100 kg / cm2 ("Fix without drilling" of Sader).
This type of putty can bond expanded polystyrene.
Polyurethane sealants are very resistant to both traction and shearing. Although they adhere to most surfaces, they are especially recommended for bonding porous materials such as wood or insulation.
They are also excellent masonry gaskets. They contain no solvents and are characterized by a low VOC content.
Their polymerization is done in contact with moisture and air. Polyurethane sealants retain great flexibility and have a very good aging resistance.
The only flaw is the presence in their formulation of isocyanate, a chemical compound that is harmful to people who are sensitive to allergies.
Neoprene mastics are transfer sizing adhesives. They are composed of polychloroprene (better known as neoprene) and organic solvents not only highly flammable, but also very odorous (alcohols, ketones, ethers, gasoline...), highly polluting and irritating.
They glue most materials, but are poorly resistant to moisture and are more suitable for indoor or outdoor collages under shelter. The collage is done in two stages by transfer.
One of the two surfaces is glued, then applied for a few seconds on the transfer surface. They must then be separated for 5 to 10 minutes for the solvents to evaporate and then to bring the two parts back in contact by exerting a strong pressure for a short time. The catch is immediate; it is impossible to reposition the pieces.
The polymeric MSs very present
Polymeric MS mastics are increasingly available on the market as they gradually replace solvent-based adhesives. They harden on contact with moisture in the air (such as polyurethane adhesive mastics).
Solvent-free, they have no odor and contain little or no VOC. These glues are weather and UV resistant.
Polymeric MS mastics can be used for all types of joints and joints. Last practical point: during the 15 to 20 minutes after installation, the room can be readjusted.
A battery of drastic tests
To judge the products, we imagined two types of tests. The first consisted of gluing wooden skirting boards, PVC trunking and tiling on the cinder block. Putties have all passed this test successfully. Second test: the verification of the load resistance. On facing blocks, we glued two wooden battens (30 x 25 x 150 mm) and two metal angles (25 x 25 x 150 mm). Two boards (800 x 200 x 20 mm) were installed on these supports, as if they were shelves. The sizing was carried out at a temperature of 10° C and allowed to dry for 4 days. The shelves were then loaded until breakage of the collage. Acrylic mastics (Pattex and Rubson) were the first to release (between 60 and 100 kg). At 140 kg load, the two Sika, the two Sader and the GEB MS gave way. The remaining five sealants, GEB's Exthane and Gebsoprene, Bosti PRO MS117 and MS118 and Pattex's PL300, were then subjected to a drop of 4.7 kg, dropped from a height of about 30 cm. The Pattex PL300 and the Bostik MS117 surrendered after 70 strokes. Both GEBs and Bostik's PRO MS118 accepted 100 consecutive mass drops before the cleats broke. Only the shocks on the angles have separated them.
DIFFERENT TYPES OF GLUE STICK SIZING
Each cartridge fits in a gun except "Go I fix" Rubson (bomb). Bonding is carried out in parallel cords spaced 5 cm apart, in studs or, as here, in a sinusoidal line if the surface to be glued is narrow.
GEB Neoprene "Gebsoprene" glues and Sader "Multi-Purpose Fasteners" are glued in two stages: after gluing, the parts must be separated to allow the solvents to evaporate and put back into contact with each other..
Rubson offers a self-extrudable putty that comes in the form of a bomb. A button (on the head) adjusts the flow. Of rather low capacity, it is intended for small repairs.
Test bench of 14 adhesive mastics
Follow the link: