CITRACONIMIDOMETHYL BENZENE

FIGURE 14.14 Structures of hexamethylene-l,6-bisthiosulfate (HTS) and l,3-bis(citraconimidomethyl) benzene (BCI-MX). 

The key performance properties of conveyor belts, particularly belt cover compounds, are flex resistance, abrasion resistance, and low heat buildup. The effect of l,3-bis(citraconimidomethyl) benzene on these key properties, in addition to cure characteristics and tensile properties, has been evaluated in a typical, NR-based belt cover formulation listed in Table 14.49. 

Schotman and co-workers tentatively assigned the new Raman peaks at 1625 and 1592 cm 1 observed during sulfur vulcanisation of squalene, to the formation of conjugated dienes and trienes, respectively [70]. When vulcanisation was carried out in the presence of l,3-di(citraconimidomethyl)benzene, this resulted in a reduced intensity of these two new peaks, corroborating that conjugated dienes and trienes, formed as a result of reversion, react with the diimide. Obviously, the diimide is not an anti-reversion agent in the sense that it prevents reversion, but it is in the sense that it repairs crosslinks when reversion has occurred. 

Bis(citraconimidomethyl)benzene, commercial name Perkalink 900, has been introduced and functions exclusively as a reversion resistor. It is understood to react via a Diels-Alder reaction to form a six-membered ring on the polymer chain (Figure 9.8). The ultimate crosslink is thermally stable and replaces sulfur crosslinks that disappear during reversion (Rubber Chemicals, 1998). 

Perkaiink 401. See Ethylene glycol dimethacrylate Perkaiink 900. See 1,3-Bis (citraconimidomethyl) benzene Perkasii KS 207. See Sodium magnesium aluminosilicate... 

One investigation suggested (19) adding 0.75 phr of antireversion chemical, l,3-bis(citraconimidomethyl) benzene (Perkalink 900) for iintroving heat resistance (mix 02). It is known that Perkalink 900 provides heat resistance to sulfur cured diene elastomers. The effect of Perkalink 900 on HR is shown in Figure 8. It is clear that Perkalink 900has a positive effect on the torque retention, which can be translated into better heat resistance. 

STABILIZATION OF DYNAMIC PROPERTIES FOLLOWING AGEING BY USING 1,3 BIS(CITRACONIMIDOMETHYL) BENZENE... 

Results of studies are examined regarding factors affecting the adhesion of steel cord to rubber. The adhesion is balanced with improved aged compound characteristics and reduced compound heat build-up through the use of l,3-bis(citraconimidomethyl)benzene, and hexa-methylene-l,6-bis(thiosulphate) disodium salt dihydrate. This combination of chemicals not only improves the... 

The phenomenon of reversion is associated with decrease in crosslink density and formation of main-chain modifications. The consequence of degradation of network and the formation of sulphidic and non-sulphidic modifications during reversion is explained. Emphasis is placed on a chemical, l,3-bis(citraconimidomethyl) benzene (Perkalink 900), which counteracts reversion by a process called crosslink compensation. Not only does Perkalink 900 add crosslinks lost during reversion, it also eliminates dienes and trienes form the network. The mechanism of Perkalink 900 crosslinking is discussed. Based on the above studies, the advantage of using Perkalink 900 in NR-based compounds is examined. Key applications and guidelines for optimal use are outlined. 25 refs. 

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. 

Kuala Lumpur, 6th-9th Oct.1997, p.427-35. 012 IMPROVING TREAD WEAR WITHOUT INCREASING HEAT BUILD-UP BY USING 1,3-BIS(CITRACONIMIDOMETHYL)BENZENE (PERKALINK 900)... 

The anti-reversion agent l,3-bis(citraconimidomethyl) benzene (Perkalink 900) reacts by a unique crosslink compensation mechanism. In doing so, the crosslink density of vulcanisates can be maintained during overcure or during ageing as encountered during service life. As a result, the mechanical properties are stabilised, thereby controlling heat build-up. The anti-reversion effect of Perkalink 900 can be applied in tread compounds in which... 

Kobe, 23rd-27th Oct.1995, p.539-42.012 HIGH TEMPERATURE CURING OF NATURAL RUBBER COMPOUNDS BY USING 1,3 BIS(CITRACONIMIDOMETHYL) BENZENE Datta RN Wilbrink J H Flexsys BV... 

The chemistry of reversion is reviewed. The concept of reversion protection by using a new chemical, 1,3 bis(citraconimidomethyl) benzene (BCI-MX), is discussed. Based on this concept, the possibility of high temperature cure is examined. 4 refs. 

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