Homogeneous Catalytic Hydrogenation of Polymers

Homogeneous Hydrogenation Art of Nitrile Butadiene Rubber: A Review

“…Downloaded by [New York University] at 10: 43 17 June 2015 During the last two decades, several comprehensive reviews have provided a thorough examination on the hydrogenation of elastomers. [2][3][4] These reviews and many other studies all illustrate that HNBR is a special important elastomer. However, there appears to be no review particularly concentrating on the advances of the hydrogenation of NBR.…”

“…3 Moreover, the heterogeneous catalytic system usually requires higher catalyst Downloaded by [New York University] at 10:43 17 June 2015 concentration and longer reaction time as well as higher temperature and pressure, which easily induces the degradation of the polymer and gelation of the reaction system. 2 The past decade has witnessed increasing attention concentrated on the homogeneous catalysts, particularly for their application in the reactions related to polymers. The application of the homogeneous catalyst with clearly defined molecular structure allows for a solid tracking of the catalytic reaction process and interpretation of the mechanism involved into it, which contributes great favor for the realization of the quantitative hydrogenation, as well as providing informative inputs for optimizing and controlling of a reaction process.…”

“…They lack thermal stability, cannot be exposed to air, and are intolerant of polar functionality. 2 Moreover, the ligands are highly complex and are costly to synthesize. Another type of Ziegler catalyst is characterized by comprising of a salt and a reducing agent as effective and necessary constituents.…”

“…1 Since then, NBR has been widely applied as an oil-resistant rubber, adhesives, coatings, plastics modifiers and so forth because of its high strength and excellent elastic properties. [2][3][4] However, due to the presence of olefinic double bonds, NBR has many drawbacks with respect to chemical, physical and mechanical properties. The main disadvantage for NBR is its poor aging property, which results in oxidative and ozonolytic degradation, and the lack of stability to resist extreme weather conditions.…”

New “Green” Route for Catalytic Latex Hydrogenation

“…The selective hydrogenation of the C=C in poly(acrylonitrile-cobutadiene) (NBR) is an important commercial process because of the great resistance of the hydrogenated NBR (HNBR) towards oxidative and thermal degradation while maintaining its elastomeric properties in chemically aggressive environments [1]. The commercial process for HNBR production involves a number of cumbersome steps, including isolating and purifying NBR solids from the latex, dissolving the NBR in large amounts of organic solvent, and recovering this solvent after the completion of hydrogenation [2].…”