SikaMelt®-292
High performance PSA hot melt for assembly
SikaMelt®-292 is a special pressure sensitive hot melt adhesive based on thermoplastic rubber for assembly applications. SikaMelt®-292 shows very good adhesion properties to a wide variety of substrates combined with an improved heat resistance compared to other rubber based hot melt adhesives. It provides high initial strength and good low temperature flexibility. After setting SikaMelt®-292 has a low surface tack.
- High cohesion and initial strength
- Very good heat resistance
- Less odor
- Low surface tack
PRODUCT BENEFITS
- High cohesion and initial strength
- Very good heat resistance
- Less odor
- Low surface tack
Areas of Application
SikaMelt®-292 is suitable to bond polar and non-polar plastics (e.g. Polypropylene), metals, textiles and felts without any surface treatment. It is designed for assembly applications in Automotive interior like carpet bonding to metal or plastic and fixation of add-on parts mainly on vehicle headliner.SikaMelt®-292 is not to be used on substrates containing monomeric plasticizer. This product is suitable for experienced professional users only. Tests with actual substrates and conditions have to be performed ensuring adhesion and material compatibility.
Product Details
| Chemical base | Thermoplastic rubber | |
| Color (CQP001-1) | Light honey color, clear or opaque | |
| Cure mechanism | Physical hardening | |
| Density | 0.95 kg/l | |
| Viscosity (by Brookfield) | at 190 °C | 12 500 mPa·s |
| Softening temperature (CQP538-5) | 142 °C | |
| Application temperature |
short term max. 1 hour | 170 – 190 °C 200 °C A |
| SAFT (CQP560-1) | 103 °C | |
| Shelf life | 24 months |
| CQP = Corporate Quality Procedure | A) only valid for nozzle |
CURE MECHANISM
SikaMelt®-292 is a physically hardening adhesive.
CHEMICAL RESISTANCE
SikaMelt®-292 is resistant to aqueous surfactant, weak acids and caustic solutions.
The chemical resistance is influenced by several factors such as chemical composition, concentration, period of exposure and temperature. Therefore a project related testing in case of chemical or thermal exposure is required.
Application
Surface preparation
Surfaces must be clean, dry and free from grease, oil and dust.
Based on the surface and type of material, a physical or chemical pre-treatment might be required. Type of pre-treatment must be determined by preliminary tests.
Application
Due to its low surface tack, SikaMelt®-292 is applied directly in a bead or dot application using adequate processing equipment. For automated applications a suitable filter system is required.
To meet the required application properties the adhesive viscosity can be adjusted by adapting the application temperature (see diagram 1).
Diagram 1: Viscosity as function of temperature
During breaks SikaMelt®-292 is to be processed as follows:
For breaks ≥ 1 h the heating needs to be lowered to 80 °C and for breaks ≥ 4 h the heating needs to be switched off.
To ensure a constant quality during the whole production process it is mandatory to protect the adhesive in the melting tank with nitrogen or carbon dioxide (to avoid possible reaction of the product with oxygen).
For advice on selecting and setting up suitable processing equipment contact the System Engineering Department of Sika Industry.
Removal
SikaMelt®-292 may be removed from tools and equipment with Sika® Remover-208 or another suitable solvent.
Hands and exposed skin have to be washed immediately using hand wipes such as Sika® Cleaner-350H or a suitable industrial hand cleaner and water.
Do not use solvents on skin.
STORAGE CONDITIONS
SikaMelt®-292 has to be stored at temperature below 40 °C in a dry place.
For transportation purposes, the storage temperature can be exceeded for a period of max. 4 weeks up to 60 °C.