RTV Silicone Rubber F23
RTV Silicone Rubber F23 is a great, general purpose RTV silicone rubber.
- Two part silicone rubber kit: liquid silicone and curing agent.
- Easy 20:1 by weight mix ratio
- Exceptional fluidity, easy to mix, easy to de-mould.
- Good tensile and tear strength, very low shrinkage.
- Room Temperature Vulcanisation (RTV) silicone rubber
- Model: F23 (23 Shore A Hardness)
- Usage: making moulds to cast polyurethane/polyester resins, plaster / gypsum, Jesmonite, candles, jewellery, toys, soaps, statues and many more
To download the technical specification please click here and select the appropriate information.
Model: Polysil F23
Usage: Silicone rubber for PU/poly resin, unsaturated resin, plaster, candles and gypsum crafts, toys, soaps, statues, casting, mould making, etc.
|Mixing ratio of curing agent (%)||5|
|Hardness (A°)||23 ± 2|
|Viscosity (mPas -25°C)||21000 ± 9000|
|Tensile strength (Mpa)||≥4.3|
|Elongation break (%)||≥480|
RTV Silicone Rubber F23 – Technical guidelines (as of January 2017):
- Shake the catalyst container well before use.
- Weigh the desired amount of base into a clean mixing container.
- Weigh the proper amount of catalyst into the container. Mix the base and catalyst together by stirring with a stick until a uniform colour is obtained. Scrape the container walls and bottom well to insure a thorough mix.
- Though it is often unnecessary to de-air the material due to its low viscosity, some may choose to do so. If so, place the container into a vacuum chamber and extract the air from the mixture using a vacuum pump capable of achieving 29 inches of mercury vacuum. The mixture will rise, crest and then collapse in the container. Interruption (bumping) of the container may be necessary to prevent the container from overflowing. Keep the mixture under full vacuum for 2 – 3 minutes.
- Slowly bleed air into the vacuum chamber. When the chamber is at atmospheric equilibrium, remove the cover plate and take out the container.
- Pour the de-aired material slowly in a steady stream from one end of the mould so that the material flows evenly over the pattern. This should minimise the entrapment of air bubbles under the flowing material.
A mould release agent may be applied on the pattern first, to improve release.
- Allow the rubber to cure before removing the cured rubber mould from the pattern. Heat acceleration is not recommended with this product.
- For the best results, allow the mould to air cure for an additional 24 hours before using it in production.
RTV Silicone Rubber F23 – Shelf life:
12 months from date of shipment when stored at 25°C in the original sealed packages.
Inhalation: remove source of contamination, move victim to fresh air and seek medical assistance immediately.
Eye contact: wash eyes with plenty water. If irritation persists seek medical attention.
Skin contact: remove contaminated clothing and launder before reuse; wash affected area thoroughly with soap and water; seek medical attention if rash develops.
Ingestion: do not induce vomiting unless instructed by a physician. Seek medical assistance immediately.
After first aid, seek appropriate on-site, paramedic or community medical support.
RTV Silicone Rubber F23 – Catalyst Information:
When adding 5% of catalyst to silicone rubber, at room temperature the working time is about 15-30 minutes, curing time is approx. 2-3 hours. To ensure an accurate mix ratio, please use a precise electronic scale to weigh the rubber and catalyst.
Mixing proportions and temperature:
- Below 0°C regardless of how much catalyst is added, the rubber will react very slowly, and never cure.
- Below 5°C with 10% of catalyst added, the rubber will react very slowly and cannot be cured within 24 hours.
- Below 15°C with 5% of catalyst added, the working time is approx. 30-40 minutes, with a curing time of about 2-3 hours.
- Temperatures about 25°C with 2% of catalyst added, the working time is about 15-30 minutes, with a curing time of about 2-3 hours.
- Temperatures about 35-40°C with 1% of catalyst added, the working time is about 15-30 minutes, with a curing time of about 2-3 hours.
RTV Silicone Rubber F23 – Notes:
Silicone rubber is greatly affected by temperature. The above testing data is purely for reference purposes, specific use is down to the user’s discretion. Before large scale application, it is recommended to take a small amount for testing purposes first. Once you are satisfied with the results, large scale production can begin. Polysil Ltd cannot be held liable for losses as a result of the above not being followed.
The more catalyst added the greater shrinkage of silicone moulds. For a precise mould strictly control mixing ratios.