Mechanochemical preparation of devulcanized ground fluoroelastomers for the enhancement of the thermal stability of nitrile–butadiene rubber vulcanizates

Abstract

Mechanochemically devulcanized ground fluoroelastomer (FKM) was used as a low‐cost functional additive for the enhancement of the thermal stability of nitrile–butadiene rubber (NBR) vulcanizates. Without the use of any chemicals, the stress‐induced mechanochemical devulcanization of ground FKM was achieved through solid‐state mechanochemical milling at ambient temperature. The sol fraction of the ground FKM was increased from its original 1.4 to 19.8% after milling; this confirmed the realization of the mechanochemical devulcanization of FKM. Moreover, the oxygen‐containing polar groups on the surface of the mechanochemically milled FKM benefitted its interfacial adhesion with the polar NBR matrix. The curing characteristics and mechanical properties of the devulcanized, FKM‐filled NBR vulcanizates were investigated and compared with those of the untreated FKM‐filled NBR vulcanizates. The results show that the mechanical properties of the devulcanized FKM‐filled NBR vulcanizates were much better than those of the untreated FKM‐filled NBR vulcanizates. The presence of the reclaimed FKM significantly increased the onset degradation temperature of the NBR vulcanizates as a result of the improved polymer–filler interaction, uniform dispersion, and high thermal stability of the reclaimed FKM. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Swelling and mechanical properties of (acrylonitrile‐butadiene rubber)/(hydrogenated acrylonitrile‐butadiene rubber) blends with precipitated silica filled in gasohol fuels

“…Examples of the rubber used for automotive applications include fluoroelastomers (FKM), acrylonitrile‐butadiene rubber (NBR), and hydrogenated nitrile butadiene rubber (HNBR). The FKM is increasingly used as high‐performance seals, gaskets, and moldings owing to their excellent thermal, oil, and chemical resistance . However, FKM is relatively expensive compared with NBR, which is usually used as seals in automotive and petroleum applications and is regarded as a specialty elastomer that offers a broad range of thermal and oil‐resistant properties.…”

“…Based on updated literature , the properties of NBR/HNBR blends are not fully documented, especially under immersion into gasohol oils. The purpose of this study was to recommend a suitable ratio of NBR to HNBR for optimum cure and mechanical properties and swelling‐resistant properties before and after immersion into gasohol oils from low‐ to high‐ethanol contents (referred to as E10, E20, and E85).…”

A novel grafting‐modified waste rubber powder as filler in natural rubber vulcanizates

“…One method is to break the sulfur crosslink bonds by mechanochemical method, biodesulfurization, microwave, or ultrasound . Lu et al . used solid‐state mechanochemical milling to devulcanize post‐vulcanized fluoroelastomer scraps.…”