Study On Preparation And Mechanical Properties Of Two Components Addition Type RTV Putty Silicone Rubber

The room temperature vulcanized(RTV) silicone rubber is divided into condensation-cured RTV silicone rubber and addition-cured RTV silicone rubber, according to the mechanism of vulcanization. Addition-cured silicone rubber has been widely used in construction, medical, electronics, aerospace and other fields because of its excellent flexibility, tenacity and strength, high plasticity, small volume shrinkage, high accuracy, excellent chemical stability, and easy to demould. Generally, the physical state of two component addition-cured RTV silicone rubber is liquid, in this paper, it is solid, and which it is easy to prepare, and could be produced industrialized, so its market prospect is broad. And also, it could be used easily. There are two kinds of hardness of the two components addition-cured RTV putty silicone rubber prepared in this paper: one is high hardness, which with a poor elasticity ranging from shore A60 to shore A75, and another is low hardness with an excellent elasticity ranging from shore A35 to shore A40. The two kinds of hardness of silicone rubber can be used for accurate mould, and the high hardness silicone rubber can also be used as dental impression materials. The main components of the two component addition type RTV putty silicone rubber are vinyl silicone oil, methyl hydrogen polysiloxane oil, and platinum catalysts, reinforce filler, and other assistants. In this paper, the effect of content and the different types of components to the mechanical properties of silicone rubber are discussed, and then to get the formulation meeting different requires.Usually, the hardness of solid silicone rubber is shore A50-shore A60, in this work, the hardness of the solid silicone rubber increased to more than shore A60, and the highest could reach shore A75 by adding the homemade base gum. And also, we can prepare the solid silicone rubber with hardness of less than shore A40, and the lowest reached shore A35 by use of the 100000mm2/s vinyl silicone oil as its basic polymer and adding 8%-10% carbon-white and 5%-10% MQ-type vinyl silicone resin. In this paper the quartz powders have a good lipophilicity and increased filling quantity through modified. The solid silicone rubber prepared by the ordinary quartz powders would be caked because of the bad compatibility between the vinyl silicone oil and the ordinary quartz powders. Modified quartz powders have a good lipophilicity, could be well dispersed in vinyl silicone oil. In this paper, the two component addition-cured RTV putty silicone rubber could not cake saved for a long time.