Influence of precipitated silica on dynamic mechanical properties and resistance to oil and thermal aging in CPE/NR blends

Abstract

ABSTRACT:Blends of 80/20 CPE/NR filled with various silica loadings were prepared, and their properties were determined. It was found that cure properties are influenced significantly by the addition of precipitated silica. Scorch time and cure time decrease with increasing silica loading, which could be explained by the thermal history attributed to the shear heating in the blending stage. An increase in crosslink density as a function of silica loading is believed to be caused by a migration of curatives to the NR phase. In terms of phase morphology, with increasing silica loading, the NR dispersed phase size decreases due to the increase in compound viscosity and, thus, the shear stress available for efficient blending. An increase in silica loading also enhances resistance to oil due to the decrease in the NR dispersed phase size associated with the dilution effect, but gives no significant impact on thermal aging resistance. According to the change in damping peak height associated with the shift in T g of the CPE phase, silica appears to preferentially migrate to the CPE phase due to the strong interaction between CPE and silanol groups of the silica surfaces.

Dynamic Mechanical Analysis and Three-Body Abrasive Wear Behaviour of Thermoplastic Copolyester Elastomer Composites

“…Also, TCE reinforced with 40 wt.% fiber and fillers had higher values of storage modulus as compared to those with 32 wt.% fibers + fillers and 15 wt.% fillers. This is because of the reinforcement fibers and fillers, leading to a strong and stiff interface between fiber/filler and polymer molecules [43]. In addition, TCE hybrid composites filled with micron sized filler particles possess higher storage modulus than those with large particles (fibers) and greater surface area occupied by the fillers, resulting in the effective matrixfiller interactions.…”

“…It can be seen from Figure 2, that the incorporation of 32 wt.% fiber + filler loading into the TCE composite decreased the damping characteristics of the composites, causing a lower and broader damping peak. This could be explained because the fiber/filler acted as a barrier to the mobility of polymer chains, which restricted the segmental motions of polymer through the strong interaction between fiber/filler and polymer molecular chains, indicating the reinforcing nature of filler with polymers [43]. Moreover, there was a reduction of the damping peak for 15 wt.% filler in TCE composites and hence a greater improvement in the fiber reinforcements.…”

Relationship Among Thermal Ageing Degradation, Dynamic Properties, Cure Systems, and Antioxidants in Natural Rubber Vulcanisates

“…Numerous studies on the dynamic mechanical properties of various rubber vulcanisates have been reported, including the effects of types and amounts of rubber [6,7] and fillers [8][9][10] , the interaction between rubber and filler [11] , the compounding ingredients and the state-of-cure [11,12] . It is found that changes in the cross-link structures (i.e., cross-link density and cross-link type) of NR vulcanisates cause variation in glass transition temperature (T g ), elastic modulus (G 0 ) and damping factor [1] .…”

The structure and dynamic properties of nitrile–butadiene rubber/poly(vinyl chloride)/hindered phenol crosslinked composites

“…Based on our knowledge, in the case of inorganic fillers filled rubber composites, the E 0 value increased obviously as the content of the filler increased. 18 But in the case of NBVC/AO-80c crosslinked composites, the E 0 value in the glassy region did not vary much as the content of AO-80 increased, whereas those in the rubbery region significantly decreased, leading to the increase of the relaxation strength. This could be explained as that the modulus of amorphous AO-80 particles was approximate to the crosslinked matrix, and so the AO-80 particles had little effect on the matrix's E 0 .…”