Knowde Enhanced TDS
Identification & Functionality
- Plastics & Elastomers Functions
- Technologies
Features & Benefits
- Labeling Claims
- Materials Features
- Ready-to-Use Product Features
- Specific Features
- Condensation-curing
- Robust curing
- Self-adhesive
- Shear thinning
- Thixotropic
Applications & Uses
- Applications
- Compatible Polymers & Resins
- Cure Method
- Plastics & Elastomers End Uses
- Application Details
- General purpose curing agent for condensation curing RTV-2 silicone rubber bases
- Typical fields of application: household appliances, automotive, mechanical engineering, electrical industry.
- Processing
Designated Use
WACKER® CATALYST T 77 PLUS is used as standard curing agent for ELASTOSIL® RTV-2 base compounds. The shear-thinning paste provides any product of the series ELASTOSIL® RT or ELASTOSIL® M with excellent adhesion properties. The adhesion strength of the cured rubber usually is independent of the type of base compound used.
Processing
The crosslinking reaction of condensation curing RTV-2 silicones is relatively robust in regard to curing inhibition. Amine containing materials, urethanes, organic compounds with sulfur-containing groups, organometallic compounds, plasticizers, lubricants, oils and grease usually do not impair the curing process itself. Nevertheless, for optimum adhesion results all substrates used should be clean, dry and free from grease, waxes, dust or other surface contaminations.
Mixing and Curing
- To ensure uniform curing both components (rubber base and curing agent) have to be thoroughly mixed, either manually or by automatic metering lines equipped with static or dynamic mixing devices. The recommended mixing ratio is 10:1 by weight.
- Potlife and curing speed can be modified within limits by adjusting the ratio of base compound to curing agent. Varying the mixing ratio between 8:1 and 12:1 usually has a small effect on the properties of the cured rubber.
- However, if the mixing ratio differs substantially from the recommended scope, preliminary tests should be carried out to check the cured material’s suitability. General information about pot life and resulting curing times is given in the respective tables "Catalyzed".
- Moreover curing speed can be slightly accelerated by raising the temperature. Heating, however, must not exceed 60 °C before curing is completed.
- After completion of the vulcanization process the self-bonding silicone rubber may continuously be exposed to constantly changing climatic conditions, UV radiation and high temperature without damage.
Removal
If removal of silicone rubber from machines or dispensing equipment is necessary, white spirit or similar nonpolar solvents are recommended. However, cleaning ideally should take place before the silicone is fully vulcanized. Cured silicone rubber needs to be removed mechanically, if necessary in combination with a swelling agent (solvent). We recommend running preliminary tests to optimize conditions for the particular application.
Properties
- Physical Form
- Typical Properties
- Catalyst Properties
- Properties
- Non-slump paste
- To be processed with base compounds of the ELASTOSIL® RT or ELASTOSIL® M series (recommended mixing ratio: 10:1)
- Very fast curing at room temperature
- Curing speed tunable by mixing ratio
- Provides condensation curing RTV-2 silicones with excellent adhesion to many substrates (glass, ceramics, wood, metals, plastics and powder coatings)
- Note
Catalyzed: Curing conditions: 23 °C, 50 % rel. humidity; all mixing ratios by weight.
- Adhesion Quality
Substrate Quality of Adhesion
Glass, Ceramic glass, Ceramics Very good Metals, e.g. aluminum, stainless steel,
iron, brass, copper
Very good Wood and engineered wood Usually very good
Thermoplastic materials, e.g. Polyamide Good to very good
PBT, PC, PPS Variable PMMA, PEEK Poor PE, PP, fluorinated polymers None
| Value | Units | Test Method / Conditions | |
| Density (at 23°C, 1013 hPa) | 1 | g/cm³ | EN/ISO 1183 |
| Dynamic Viscosity (at 25°C, Shear rate 0.5 s⁻¹) | approx. 200000 | mPa·s | DIN EN ISO 3219 |
| Dynamic Viscosity (at 25°C, Shear rate 25 s⁻¹) | approx. 15000 | mPa·s | DIN EN ISO 3219 |
| Value | Units | Test Method / Conditions | |
| Curing Time (Processing with slowly curing base compounds, e.g. ELASTOSIL® M 4503 or ELASTOSIL® M 4511) | min. 3 | hours | — |
| Curing Time (10:1, Processing with base compounds of medium curing speed, e.g. ELASTOSIL® RT K or ELASTOSIL® RT 563) | 1.5 - 2.5 | hours | — |
| Curing Time (10:1, Processing with fast curing base compounds, e.g. ELASTOSIL® RT 426, RT 428, RT 771, RT 772, RT 773, RT 774 or RT 778) | 30 - 45 | minutes | — |
| Curing Time (12:1, Processing with base compounds of medium curing speed, e.g. ELASTOSIL® RT K or ELASTOSIL® RT 563) | 2.5 - 3 | hours | — |
| Curing Time (12:1, Processing with fast curing base compounds, e.g. ELASTOSIL® RT 426, RT 428, RT 771, RT 772, RT 773, RT 774 or RT 778) | 60 - 90 | minutes | — |
| Curing Time (8:1, Processing with fast curing base compounds, e.g. ELASTOSIL® RT 426, RT 428, RT 771, RT 772, RT 773, RT 774 or RT 778) | 20 - 30 | minutes | — |
| Curing Time (8:1, Processing with base compounds of medium curing speed, e.g. ELASTOSIL® RT K or ELASTOSIL® RT 563) | 45 - 90 | minutes | — |
| Curing Time (8:1, Processing with slowly curing base compounds, e.g. ELASTOSIL® M 4503 or ELASTOSIL® M 4511) | min. 2 | hours | — |
| Pot Life (10:1, Processing with base compounds of medium curing speed, e.g. ELASTOSIL® RT K or ELASTOSIL® RT 563) | 15 - 45 | minutes | — |
| Pot Life (10:1, Processing with fast curing base compounds, e.g. ELASTOSIL® RT 426, RT 428, RT 771, RT 772, RT 773, RT 774 or RT 778) | 5 - 10 | minutes | — |
| Pot Life (10:1, Processing with slowly curing base compounds, e.g. ELASTOSIL® M 4503 or ELASTOSIL® M 4511) | 50 - 80 | hours | — |
| Pot Life (12:1, Processing with base compounds of medium curing speed, e.g. ELASTOSIL® RT K or ELASTOSIL® RT 563) | 45 - 75 | minutes | — |
| Pot Life (12:1, Processing with fast curing base compounds, e.g. ELASTOSIL® RT 426, RT 428, RT 771, RT 772, RT 773, RT 774 or RT 778) | 8 - 12 | minutes | — |
| Pot Life (12:1, Processing with slowly curing base compounds, e.g. ELASTOSIL® M 4503 or ELASTOSIL® M 4511) | min. 80 | minutes | — |
| Pot Life (8:1, Processing with slowly curing base compounds, e.g. ELASTOSIL® M 4503 or ELASTOSIL® M 4511) | 20 - 60 | minutes | — |
| Pot Life (8:1, Processing with fast curing base compounds, e.g. ELASTOSIL® RT 426, RT 428, RT 771, RT 772, RT 773, RT 774 or RT 778) | 3 - 6 | minutes | — |
| Pot Life (8:1, Processing with base compounds of medium curing speed, e.g. ELASTOSIL® RT K or ELASTOSIL® RT 563) | 5 - 15 | minutes | — |
Regulatory & Compliance
- Certifications & Compliance
Safety & Health
- Safety Notes
While curing WACKER® CATALYST T 77 PLUS releases a total of approx. 1.5 - 2 wt.% alcohol. These vapors should not be inhaled for long periods or in high concentrations. Hence ventilation of the work place is recommended.
Packaging & Availability
- Country Availability
- Regional Availability
Storage & Handling
- Storage Information
Store in a dry and cool place.