Silicone rubbers high temperature vulcanising

Silicones are well known for their versatility, which makes them ideally suitable for a variety of applications. The fluids can be used as solvents, as foam-control systems, or as release agents (20% of the total volume). High-molecular-weight silicones are mainly used in rubber applications such as High Temperature Vulcanisable (HTV) and Room Temperature Vulcanisable (RTV) (43%), resins (4%), or specialties (15%). Other applications for silicones are masonry protection (8%), textiles (7%), and paper coatings (3%). Silicones can be uniquely tailored for each application area by substitution by reactive groups, allowing them to be cured by different mechanisms. 

High temperature vulcanising, solid silicone rubber (HTV),... 

A TG-DTA study of the thermochemical processes occurring at vulcanisation temperatures with N-oxydiethylene-2-benzthiazyl sulphenamide and N-cyclohexyl-2-benzthiazyl sulphenamide and their mixtures with sulphur showed the formation of high molecular weight polysulphides [73]. The influence of metallic oxides (Fe203, Sn02) on hot air ageing of one-pack room temperature vulcanised fluorosilicone rubber has been studied by means of TG-DTA [74, 75]. TG-DTA and TG were both applied to study the thermal characteristics of room temperature vulcanised silicone rubber [76]. 

The main properties of some rubber compounds and vulcanised rubbers, as well as their applications, are given in Table 20. As seen from the table, silicone elastomer-based rubbers are designed for prolonged use in a wide range of temperatures from -50 to +250 °C, some from -70 to + 350 °C (for a short period of time). These rubbers are efficient in air, ozone and in an electric field rubbers based on IRP-1339 and IRP-1401 compounds are also efficient in case of limited air supply. They function well in high humidity and under the influence of oxidants, hot water, vapour and low pressure. They are stable in weak-acid and weak-alkali media and are nontoxic. 

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