Why Silicone Mold Do Not Cure?

The curing agent of silicone rubber is a crosslinking agent of two-component condensed type silicone rubber (RTV - 2). Cross -linking time can be adjusted by mixing ratio. Curing agent with appearance of white paste that takes yellow slightly is a kind of diacyl organic peroxide. The curing agent with the features of high strength and good transparency is used as a vulcanizing agent of silicone rubber. As you know, the silicone mold is composed of silicone rubber and curing agent and many customers find a phenomenon that the mold is often uneven curing. Next, I will tell you why the silicone molds do not cure and how should we deal with this situation?   First of all, you have to make sure the proportion of curing agent is correct. This ratio of curing agent too much or too little will affect the curing of silicone rubber. Component A is silicone rubber, and component B is curing agent or vulcanizing agent, usually the mixing ratio will be 2-3%. Such as to 100G silicone rubber should be added 2G catalyst and then mix them totally(Note: the weight of the silicone and catalyst should be weighted correctly. According to local weather, the mixing ratio can be 100 to 2 under room-temperature 25 ℃; if the local weather is about 10 ℃, then the maximum mixing ratio should be 5%; When local temperature is -5 ℃, no reaction will happen between the silicone and hardener; once the temperature of local weather is 38-45 ℃, the mixing ratio of silicone and curing agent should be 1 %).   The second reason may be that you did not mix the silicone and curing agent evenly. Molding silicon rubber is a kind of flowing liquid and it contains two parts. Part A is a kind of white flowing liquid and part B is the curing agent. Remember to mix part A and part B evenly, otherwise the silicon rubber will be partly solidified and this will give birth to difficulties in your final operation. What’s more, the finished moulds will meet a short life. All of these will cause a waste of silicon rubber.     In addition, different types of curing agents cannot be mixed. For example, the use of condensation type cured silicone and addition type cured silicone must be distinguished strictly. As we all know, condensation type rubber added organic tin catalyst containing acid, alkali and N, S, P and other organic matter may affect the rubber vulcanization. Therefore, these substances can not be mixed with the use of addition type cure silicone. If the mold originally used for condensation cured type silicone, it must be cleaned with gasoline before use, otherwise the surface of mold can not be cured. In short, condensation cured type mold and condensation cured type mold must be separated, and the two cannot be mixed use. In other words, we must use the appropriate type of curing agent. Operating tools should be classified, must not be mixed.   Shenzhen Hong Ye Jie Technology Co., Ltd. is recognized as the global leading in the manufacturer of high quality silicone rubber products in an unsurpassed variety of RTV-2 silicone, HTV silicone rubber, LSR, etc. Our company provides the silicone raw materials. Currently 95% of our products has been widely exported to more than 90 countries and gets its great reputation from all over the world. We are sure that our superior silicone rubber will bring you first class products.   What you need is what we pursue. we'll provide free technology service and free technical training. We are sure that you will enjoy our silicone products and service! If any more information required, please feel free to contact with us at e-mail: info@szrl.net or tour our website:http://www.szrl.net, thank you!