In the use of open mill mixing process, may be due to some reason resulting in rubber burning, in order to avoid burning rubber, Baoding technical engineer to us for the way to avoid burning, the details are as follows:
The first to reduce the amount of cooperation accelerator, but this will lead to reduce the physical properties of rubber products, it is important to understand that the status of application of accelerator alone rarely, once the cooperation of doubt, can not avoid the scorch.
The mills in general, the main promoter for general rubber with sulfonyl amine accelerator, the main accelerator DM is universal accelerator, accelerator M coke burning high time sulfonyl amine accelerator although there is resistance to coke burning, but due to its slow curing speed, so according to the requirements of choice with glue, thiurams accelerator assisted system. In the summer high temperature season, auxiliary accelerator to reduce the use of, while the main accelerator is not as far as possible to reduce the amount of cooperation.
The reclaimed rubber 20 phr 10- in general rubber, glue is made after blending, which can avoid the Scorch effect of blend, to think about planning additivity formula, make some necessary changes on the basis of scorched rubber physical properties and curing on
With silica gel materials, to increase two glycol, polyethylene glycol, organic amine accelerators such as SL, but increased more than cooperation would cause excessive agent scorch, so it is necessary to pay attention to.
The standard amount of cooperation should be (compared with silica) two glycol and polyethylene glycol (molecular weight of 400) of, organic amine accelerator SL is 2.5%. Although there are a lot of discussions in the cooperation, as mentioned above, if we still can not avoid scorch, we can increase the anti coking agent. It is an organic compound composed of two kinds of organic acids, nitroso compounds and phthalic acid, phthalic acid, benzoic acid, and benzoic acid, etc., and is a kind of organic compound. Because of the two polluting nitro aniline, so cannot be used for light colored rubber products.
Anti coking agent in the delayed vulcanization together, but also slowed down the rate of vulcanization, the mixer because it will reduce the degree of crosslinking, so do not use a lot, according to the experience of many years of experience in the engineer, the amount should not exceed 0.4%. If there is a need for more than 0.4%, it is important to reduce the dosage of the accelerator. Should not use the high accelerator, high anti coking agent cooperation.
On the basis of the original data, the scale of scorch time is set up on the basis of the original data. For example, set the Mooney scorch time, 125 C, 15 25m in. MS, a method of mixing the available water cooling and air cooling or both with the film cooling to room temperature. Even if the roll out of the plastic material, if there is the risk of scorch, open the machine can be carried out on the edge of the wind cooling side of the roll, perhaps after a certain length of cut and then air cooling. In accordance with the requirements can also be air-conditioned room, cold storage.
The glue is required remiling, first will be back mixing glue into the hot mill thermal refining, in recognition of the compound did not attack scorch condition after adding a new mixed rubber mixing, if the operation procedure and on the contrary, it will cause all the scorch.