The butyl rubber synthesized from isobutylene and a small amount of isoprene is excellent in airtightness and has extremely low air permeability during use. It is widely used in the production of inner tubes of motor vehicles and non-motor vehicles; butyl regeneration from waste butyl inner tube processing Glue continues the high air tightness of butyl rubber. It can be used in butyl inner tube formulations to reduce the cost of raw materials. Many inner car tires even use butyl reclaimed rubber completely. When butyl rubber and butyl reclaimed rubber are used to produce butyl inner tube, sulfur vulcanization is often used, and different kinds of accelerators are used to obtain different vulcanization effects 1JLYY812.
1. Sulfur/accelerator M/TMTD vulcanization
The rubber accelerator M is an overspeed accelerator. It has a low critical temperature and is easily scorched during vulcanization. It is generally used in combination with other types of accelerators. It also functions as a plasticizer during use. The rubber accelerator TMTD is a post-effect super accelerator. , a typical thiram-like accelerator. When the butyl inner tube is selected for sulfur vulcanization, the accelerator M and the accelerator TMTD are used in combination, and the sulfur/accelerator M/TMTD is generally used in an amount of 2/0.5/1 part, and the vulcanization speed is appropriate and safe in processing.
2. Promoter DM/TDEDC vulcanization
The rubber accelerator DM is a general-purpose accelerator, which is easy to disperse and not pollute in the rubber compound, and has excellent aging resistance after vulcanization. The rubber accelerator TDDDC is a typical high-reactivity super accelerator, which is mostly used for low-temperature vulcanization and rapid. Vulcanized, often used in combination with a thiazole accelerator. In the production process of butyl rubber or reclaimed rubber inner tube, when DM and TDDDC are used together, the vulcanization speed is fast, the physical properties of vulcanized rubber are good, and the vulcanization reverse is small, but there is a tendency of scorching during vulcanization, which requires special attention. In the butyl inner tube formulation, the addition ratio of the accelerator DM/TDEDC is generally controlled at 1/1.5 parts.
3. Promoter DTDM/TMTD vulcanization
When using butyl rubber or butyl reclaimed rubber to produce inner tube, rubber manufacturers can also use the accelerator DTDM and the rubber accelerator TMTD. The dosage of DTDM and TMTD is generally controlled at about 2 parts. The vulcanization rate is slow during vulcanization, but processing High safety, vulcanized rubber has better compression resistance and heat resistance. Among them, the rubber accelerator DTDM can decompose active sulfur only at a specific vulcanization temperature, so the operation is safe and there is no scorch problem, but the vulcanization rate itself is slow, and it is often combined with a thiazole accelerator, a thiura accelerator or two. The thiocarbamate accelerator is used in combination to increase the vulcanization rate. The thiura-like accelerator TMTD has a fast vulcanization rate and a short scorch time, and is often used in combination with DTDM.
When butyl rubber is produced by using butyl rubber or butyl reclaimed rubber, since the butyl reclaimed rubber itself contains a certain amount of vulcanizing agent and accelerator, the amount of each compounding agent in the vulcanization system of the inner tube formulation containing butyl reclaimed rubber needs to be appropriate. Adjustment. At present, sulfur vulcanization system is widely used in the production of butyl inner tube. Sulfur vulcanization system can be divided into ordinary sulfur vulcanization system, semi-effective vulcanization system and effective vulcanization system. The rubber accelerators TDEDC and DTDM are both semi-effective vulcanization systems and effective vulcanization systems. For commonly used accelerator products, the amount of sulfur in the DTDM-containing sulfur vulcanization system should be appropriately reduced or not used.
Different vulcanization systems have different vulcanization effects, and the butyl inner tube production plant can select a suitable vulcanization system according to specific needs and equipment. The above vulcanization system can be selected when using butyl rubber/recycled rubber to produce most butyl products such as waterproof materials and rubber linings.