Nitrile rubber has excellent oil resistance, wear resistance, heat resistance and strong adhesion, and is widely used in various oil-resistant parts, seals, transmission belts, hoses, rubber sheets, rubber rollers, foam rubber, plastic modification materials, etc. Nitrile-butadiene rubber is a copolymer of acrylonitrile and butadiene monomers, which has good processing performance in general; but in actual production, the following 6 issues need to be paid attention to when processing nitrile-butadiene rubber.
1. Points for attention in plasticizing of nitrile rubber
Nitrile rubber itself has good thermal stability, and thermal plasticization cannot increase the plasticity of nitrile rubber. Stable plasticity.
2. Points for attention in nitrile rubber mixing
It is relatively difficult to mix nitrile rubber, the powder is not uniformly dispersed during mixing, it is not easy to wrap the roll, and the rubber compound generates large heat. It is necessary to use low temperature mixing, and pay attention to the feeding sequence and capacity. In actual production, the more acrylonitrile content of the nitrile rubber, the better the oil resistance of the rubber compound; but the acrylonitrile unit of the nitrile rubber will reduce the solubility of sulfur, so sulfur should be added first during mixing; Small powders such as zinc oxide also need to be added first to avoid affecting the physical properties of the rubber compound.
3. Nitrile rubber has low self-adhesion, large heat generation during mixing, and poor roll wrapping, so special attention should be paid during processing.
4. Points for attention when calendering nitrile
The calendering and extruding operations of nitrile rubber are more difficult than natural rubber, and attention needs to be paid to the formulation design of the rubber compound. In actual production, the addition of softeners such as esters, coal tar and coumarone to the formulation of nitrile rubber products is conducive to the adhesion among the rubber compound and the fabric; the low content of rubber is conducive to the smoothness of the rubber compound after calendering.
5. Points for attention in vulcanization of nitrile rubber
In actual production, nitrile rubber has no reverse vulcanization phenomenon during vulcanization, and can be vulcanized at a higher temperature. The deep vulcanization degree can reduce the compression deformation of the rubber compound; low temperature vulcanization can improve the tensile strength of the nitrile rubber compound 2ELYY82, but Vulcanizate is slightly less water resistant. In addition, under-vulcanization of nitrile rubber will adversely affect the compression deformation, aging resistance and oil resistance of the rubber compound. Therefore, when nitrile rubber is vulcanized, the vulcanization parameters must be set reasonably to ensure that the rubber compound is fully and uniformly vulcanized.
6. The hot tear performance of nitrile rubber is poor, and the vulcanized rubber products need to be cold-started.
Compared with nitrile raw rubber, nitrile reclaimed rubber has a lower price and better processing performance. The rational use of nitrile reclaimed rubber in the formulation of rubber products with nitrile rubber as the main raw material can not only reduce costs, but also improve rubber processing. Craftsmanship, the editor will continue to share with you the skills of combining nitrile rubber/nitrile reclaimed rubber to produce rubber products.
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