XYSIL® fumed silica is an efficient reinforcement and rheology control additives for silicone rubber.
Benifit from the unique particle characteristics, XYSIL® fumed silica delivers superior reinforcement while having a relatively minor impact on transparency. The silicone rubber performance is impacted by primary particle size, aggregate size, and surface chemistry.
APPLICATION:
Xunyu offers a range of untreated fumed silica for optimum performance in silicone applications including:
- Room Temperature Vulcanizing (RTV) Silicone Sealant
- High Temperature Vulcanizing (HTV) Silicone Rubber
- Liquid Silicone Rubber (LSR)
In RTV silicone sealant
XYSIL® fumed silica provides thixotropy and reinforcement for RTV silicone sealants, while its shear-thinning property provides thickening and sag resistance at rest or low shear and thinning at high shear for easy application.
In HTV silicone rubber and LSR
XYSIL® fumed silica strengthens the cured rubber, increasing hardness, modulus, tensile strength and tear strength. Unlike other reinforcing fillers, XYSIL® fumed silica can be used in transparent or clear applications.
As the surface area of fumed silica increases, so does thickening and reinforcement. However, high surface area XYSIL® fumed silica requires high shear dispersion equipment to achieve optimal performance. In general, XYSIL® 150 is used in RTV silicone sealant; XYSIL®200 and XYSIL®300 are used in HTV silicone rubber and LSR.
Fumed Silica XYSIL® for Silicone Rubber
| Sytem | XYSIL® Grade | Concentration in wt.% | Effect |
|---|---|---|---|
| RTV-1 Silicone Sealant | XYSIL®150 XYSIL®200 |
3.0-30 | Reinforcement, Thixotropy |
| RTV-molding compound(2 components) | XYSIL®200 | 3-30 | Reinforcement, Thixotropy |
| HTV Silicone Rubber | XYSIL®200 | 5.0-35 | Reinforcement, sag resistance, dispersability, surface quality, life duration |
| Liquid Silicone Rubber | XYSIL®200 XYSIL®300 XYSIL®380 |
5-30 | Rheology control, sag resistance, reinforcement, anti-settling |