Sikaflex®-219 LM
High performance, low-modulus elastomeric polyurethane sealant
Sikaflex®-219 LM is a one-component, low-modulus polyurethane sealant. It adheres well to a wide variety of substrates and cures on exposure to atmospheric moisture. Sikaflex®-219 LM exhibits very good recovery and is ideal for sealing applications requiring high joint movement capability.
- Very good sag resistance
- Bonds well to a wide variety of substrates
- Good gap-filling properties
- High joint movement capability
- Can be painted and sanded
- Low odor
PRODUCT BENEFITS
- Very good sag resistance
- Bonds well to a wide variety of substrates
- Good gap-filling properties
- High joint movement capability
- Can be painted and sanded
- Low odor
Usage
Sikaflex®-219 LM is suitable for joints subject to movement. Typical applications are sealing between logs in log homes, installation and perimeter sealing of windows and doors, and Exterior Insulation Finish Systems (EIFS). Sikaflex®-219 LM adheres well with the most common substrates in these applications such as metals, metal primers and paint coatings (2-component systems), and wood. Seek manufacturer’s advice and perform tests on original substrates before using Sikaflex®-219 LM on materials prone to stress cracking. This product is suitable for experienced professional users only. Tests with actual substrates and conditions have to be performed ensuring adhesion and material compatibility.Packaging
| Cartridge | 300 ml |
Product Details
| Chemical base | 1-component polyurethane | |
| Color (CQP001-1) | White, aluminum gray, log home tan, deep bronze | |
| Cure mechanism | Moisture-curing | |
| Density (uncured) | depending on color | 1.36 kg/l (11.3 lb/gal) |
| Non-sag properties | Good | |
| Application temperature | ambient | 5 ─ 40 °C (41 ─ 104 °C) |
| Skin time (CQP019-1) | 3 hours A | |
| Curing speed (CQP049-1) | (see diagram) | |
| Shore A hardness (CQP023-1 / ISO 48-4) | 25 | |
| Tensile strength (ASTM D412) | 0.9 MPa (130 psi) | |
| Elongation at break (ASTM D412) | 700 % | |
| Service temperature (CQP513-1) | -40 ─ 90 °C (-40 ─ 194 °F) | |
| Shelf life | 12 months B |
| CQP = Corporate Quality Procedure | A) 23 °C (73 °F) / 50 % r.h. | B) stored below 25 °C (77 °F) |
CURE MECHANISM
Sikaflex®-219 LM cures by reaction with atmospheric moisture. At low temperatures the water content of the air is generally lower and the curing reaction proceeds somewhat slower (see diagram 1).
Diagram 1: Curing speed Sikaflex®-219 LM
CHEMICAL RESISTANCE
Sikaflex®-219 LM is generally resistant to fresh water, seawater, diluted acids and diluted caustic solutions; temporarily resistant to fuels, mineral oils, vegetable and animal fats and oils; not resistant to organic acids, glycolic alcohol, concentrated mineral acids and caustic solutions or solvents.
Application
Surface Preparation
Surfaces must be clean, dry and free from grease, oil, dust and contaminants.
Surface treatment depends on the specific nature of the substrates and is crucial for a long lasting bond. Suggestions for surface preparation may be found on the current edition of the appropriate Sika® Pre-Treatment Chart. Consider that these suggestions are based on experience and have in any case to be verified by tests on original substrates.
Application
Sikaflex®-219 LM can be processed at temperatures (climate and product) between 5 °C and 40 °C (41 °F and 104 °F) but changes in reactivity and application properties have to be considered. The optimum temperature for substrate and process material is between 15 °C and 25 °C (59 °Fand 77 °F). Sikaflex®-219 LM can be processed with manual, pneumatic or electric driven piston guns.
Tooling and finishing
Tooling and finishing must be carried out within the skin time of the product. It is recommended using Sika® Slick. Other finishing agents must be tested for suitability and compatibility prior the use.
Removal
Uncured Sikaflex®-219 LM may be removed from tools and equipment with Sika® Remover-208 or another suitable solvent. Once cured, the material can only be removed mechanically.
Hands and exposed skin have to be washed immediately using a suitable industrial hand cleaner and water.
Do not use solvents on skin.
Overpainting
Sikaflex®-219 LM can be painted after formation of a skin. If the paint requires a baking process, best performance is achieved by allowing the sealant to fully cure first. 1C-PUR and 2C-acrylic based paints are usually suitable. All paints have to be tested by carrying preliminary trials under manufacturing conditions.
The elasticity of paints is usually lower than that of sealants. This could lead to cracking of the paint in the joint area.