HEXAMETHYLENE DISODIUM DIHYDRATE

Biscitraconimidomethylbenzene and hexamethylene bisthiosulphate disodium dihydrate, alone and in combination, were evaluated as anti-reversion agents in thick sectioned NR articles cured at high and low temperatures. Effects on cure characteristics and the mechanical properties of vulcanisates were investigated. 

Na-S03-S-(CH2)6-S-S0JNa+ 2H2O Hexamethylene-1,6-bis (thiosulfate) disodium salt dihydrate... 

Na SOs — S — (CHjX — S—SOjNa" 2H2O Hexamethylene -1,6- bis(thiosulfate) disodium salt, dihydrate... 

Addition of Duralink HTS (hexamethylene-1,6-bis(thiosulfate), disodium salt dihydrate) improves adhesion characteristics under ageing environments (157). Formulations without H/R bonding systems are also available (157). 

The optimising of a tyre compound to improve reversion resistance is discussed with reference to the use of two new rubber chemicals developed by Flexsys. They are 1,3 bis(citraconimidomethyl benzene) (BMI-MX) and hexamethylene-1,6-bisthiosulphate disodium salt dihydrate (HTS), which are claimed to provide two different ways to improve the thermal ageing resistance of sulphur-based vulcanisates as compared to existing technology. Each functions by uniquely different mechanisms of action and each provides different levels of performance improvements. A comparison is made of HTS and BCI-MXto conventional cure systems and semiefficient cure systems to illustrate the potential benefits of these approaches to address reversion in tyre compounds. 5 refs. 

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