Compared with natural rubber, nitrile rubber has low unsaturation, and the amount of sulfur needs to be appropriately reduced. Selecting sulfur-vulcanized nitrile rubber or nitrile reclaimed rubber requires an appropriate increase in the amount of accelerator to increase the vulcanization rate. The physical properties of nitrile vulcanizate are directly related to the type and amount of vulcanization accelerator. So how should manufacturers of nitrile rubber products determine the type and amount of accelerator in the sulfur vulcanization system?
1. Combined with the processing characteristics of nitrile rubber
Nitrile rubber is an unsaturated rubber containing polar groups. Vulcanization accelerators commonly used in unsaturated rubbers such as natural rubber can be used in nitrile rubber sulfur vulcanization systems, such as thiazole accelerator M/DM, sulfenamide accelerators Agent CZ/NS and thiuram accelerator TMTD/TMTM can be combined with sulfur to form a nitrile rubber sulfur system.
It should be noted that the use of basic accelerators such as guanidine accelerators and aldamine accelerators in nitrile rubber is not ideal. Use guanidine accelerators or aldamine accelerators in combination with sulfur 2LLYY618 When nitrile compound is used, scorch is easy to occur, and the permanent deformation of the vulcanized rubber after compression is increased. Therefore, it is best not to use these two types of accelerators in nitrile rubber products.
2. Consider the physical properties of nitrile rubber products
The nitrile rubber products of different use occasions have different requirements on the physical properties of the rubber compound. When selecting the accelerator combined with sulfur, it is necessary to combine the specific physical property requirements of the nitrile rubber products.
In general, the vulcanization system used by sulfur in combination with accelerator M and accelerator CZ has fast vulcanization speed and good vulcanizate performance. It is a vulcanization system commonly used in the production of nitrile rubber products; butyronitrile with strict heat resistance requirements Rubber products can choose low sulfur compound, a small amount of sulfur and thiuram accelerator such as accelerator TMTD, some rubber product manufacturers will also choose non-sulfur compound; when the rubber compound is required to have good compression permanent deformation resistance, sulfur compound promotion After TS curing, the vulcanized rubber has low compression set and low scorch tendency.
Nitrile rubber and nitrile reclaimed rubber can be used in the production of various types of oil-resistant rubber products such as oil seals, oil-resistant rubber sheets/rubber pads, oil-resistant soles, oil-resistant rubber boots, rubber rollers, and wear-resistant parts, shock-absorbing blocks, rubber gloves, etc. Different types of nitrile rubber products need to adjust the physical properties of nitrile vulcanizate through different vulcanization accelerators to meet the performance requirements of nitrile rubber products. In actual production, nitrile rubber can not only use sulfur vulcanization, but also can choose peroxide vulcanization, resin vulcanization, metal oxide vulcanization, etc. Later editors will continue to share with you vulcanizing agent when nitrile rubber is vulcanized using other vulcanization systems Selection tips with accelerators.