Curable composition based on nitrile rubber containing epoxy groups

Abstract

Vulcanizable composition comprises (i) at least one epoxy group-containing, optionally completely or partially hydrogenated nitrile rubber containing repeating units derived from e.g. at least one conjugated diene, (ii) at least one Lewis- and / or Bronsted base as a crosslinking agent, (iii) at least one crosslinking accelerator comprising thiuram, xanthates, thioureas, dithiocarbamates, and carbamates, (iv) less than 2.5 pts. wt. further crosslinking agents different from the component (ii), and (v) less than 2.5 pts. wt. further crosslinking accelerator different from the component (iii). Vulcanizable composition comprises (i) at least one epoxy group-containing and optionally completely or partially hydrogenated nitrile rubber containing repeating units derived from e.g. at least one conjugated diene, (ii) at least one Lewis- and / or Bronsted base as a crosslinking agent, (iii) at least one crosslinking accelerator comprising thiuram, xanthates, thioureas, dithiocarbamates, and carbamates, where the component (ii) is different from the component (iii), (iv) less than 2.5 pts. wt. (based on 100 pts. wt. component (i)) further crosslinking agents different from the component (ii), and (v) less than 2.5 pts. wt. (based on 100 pts. wt. component (i)) further crosslinking accelerator different from the component (iii). Independent claims are also included for: (1) preparing the above vulcanizable composition, comprising mixing the component (i) with the component (ii); (2) producing vulcanizates based on the component (i), comprising crosslinking the vulcanizable composition by increasing the temperature to 20-250[deg] C, preferably 50-230[deg] C; and (3) vulcanizates comprising the component (i).

Description

technical field [0001] The present invention relates to curable compositions based on optionally fully or partially hydrogenated nitrile rubber containing epoxy groups and specific crosslinking agents, their production process, the resulting vulcanizate production process, the resulting Vulcanized rubber, and fully or partially hydrogenated nitrile rubber containing epoxy groups. Background technique [0002] Nitrile rubber (often also referred to simply as "NBR") is understood to mean a compound of at least one α,β-unsaturated nitrile, at least one conjugated diene and optionally one or more other copolymerizable monomers. Copolymer or terpolymer rubber. Hydrogenated nitrile rubber (“HNBR”) is understood to mean corresponding copolymers or terpolymers in which all or part of the C=C double bonds of the copolymerized diene units are hydrogenated. [0003] Over the years, NBR and HNBR have established a strong position in the field of specific elastomers. They have very go...

AI Technical Summary

Problems solved by technology

However, US2010 / 0152365A1 does not describe whether and in what way selection of a suitable crosslinker system can improve the compression set at relatively high temperatures and prolonged stress periods

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