Selective hydrogenation of nitrile butadiene rubber latex using Catmetium®RF 4 catalyst

• Published in: Catalysis today 2023-01, Vol.407, p.80-88
• Main Authors: Tong, Weichao, Chen, Hanchu, Zhang, Yuxiang, Zhang, Zhuo, Fu, Yunlei, Qi, Haocheng, Zhou, Defang, Li, Yanyan, Wang, Hui
• Format: Article
• Language: English
• Subjects: Catalysis; CatMETium® RF 4; Hydrogenation; Kinetic behavior; Mass transfer; NBR latex
• ISSN: 0920-5861; 1873-4308
• DOI: 10.1016/j.cattod.2022.02.015

Hydrogenation of nitrile butadiene rubber (NBR) latex is an important topic in the field of chemical modification of unsaturated diene-based polymers. At present, the main challenge that restricts the large-scale production of hydrogenated nitrile rubber (HNBR) via latex hydrogenation way is how to reduce or even eliminate the use of organic solvents and to achieve a high rate of hydrogenation combined with a low amount of catalyst. We found a high-efficiency catalyst, i.e., catMETium®RF 4, which can directly hydrogenate NBR latex. The effects of temperature, hydrogen pressure, concentration of [CC]0 and agitation speed on the rate of hydrogenation were fully investigated. It was found that by using catMETium®RF 4 catalyst to prepare HNBR, the rate of hydrogenation of NBR latex can be increased drastically to achieve a high CC conversion of 95 mol% with a very low catalyst level of 0.02 wt%, which greatly decrease the demand on the recovery of a homogeneous catalyst from HNBR matrix. In addition, the hydrogenation of HNBR latex by catMETium®RF 4 was completely free of organic solvents and no cross-linking was found. [Display omitted] •The catMETium®RF 4 can be used for direct hydrogenation of NBR latex.•HNBR can be obtained with a quite low catalyst loading.•The stability of NBR latex is unchanged during the hydrogenation process.•The kinetic behavior of NBR latex hydrogenation is proposed.