Improvement of the homogeneity of SBR/NBR blends using polyglycidylmethacrylate‐g‐butadiene rubber

Abstract

Polyglycidylmethacrylate grafted butadiene rubber (PGMA-g-BR) was synthesized by a graft solution copolymerization technique. The PGMA content was determined through titration against HBr. The PGMA-g-BR was blended with styrene butadiene rubber/butadiene acrylonitrile rubber (SBR/NBR) blends with different blend ratios. The SBR/NBR (50/50) blend was selected to examine the compatibility of such blends. Compatibility was examined using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and viscosity measurements. The scanning electron micrographs illustrate the change of morphology of the SBR/NBR rubber blend as a result of the incorporation of PGMA-g-BR onto that blend. The T g s of SBR and NBR in the blend get closer upon incorporation of PGMA-g-BR 10 phr, which indicates improvement in blend homogeneity. The intrinsic viscosity () versus blend ratio graph shows a straight-line relationship, indicating some degree of compatibility. Thermal stability of the compatibilized and uncompatibilized rubber blend vulcanizates was investigated by determination of the physicomechanical properties before and after accelerated thermal aging. Of all the vulcanizates with different blend ratios under investigation, the SBR/NBR (25/75) compatibilized blend possessed the best thermal stability. However, the SBR/NBR (75/25) compatibilized blend possessed the best swelling performance in brake fluid. The effect of various combinations of inorganic fillers on the physicomechanical properties of that blend, before and after accelerated thermal aging, was studied in the presence and absence of PGMA-g-BR.

Properties and morphologies of elastomer blends modified with EPDM‐g‐poly[2‐dimethylamino ethylmethacrylate]

“…This result is very close to our previous grafting efficiency measurements 29 of other acrylates onto rubber materials via other analytical techniques such as titration and/or elemental analysis. The GPC trace of the modified EPDM is shown in Figure 2.…”

Morphology and rheology of (styrene-butadiene rubber/acrylonitrile-butadiene rubber) blends filled with organoclay: The effect of nanoparticle localization

“…It is known that by the use of a compatibilizer, the morphology of immiscible blends can be stabilized through suppressing coalescence and enhancing interfacial adhesion which results in a finer droplet size (Huitric et al, 2009). During the last decades, block, graft or random copolymers have been used as the compatibilizers for immiscible polymer blends to prevent phase separation (Ramesan and Rosamma, 2001;Botros et al, 2006;Khalf et al, 2010;Noriman et al, 2010); however in recent years, using inorganic nanoparticles, as the compatibilizer have attracted particular attention (Wang et al, 2001;Steinmann et al, 2002;Gu et al, 2004;Elias et al, 2007). For instance, Elias et al (2007) investigated the effect of hydrophilic and hydrophobic silica on morphology and rheology of the polypropylene/polystyrene (PP/PS) and also PP/ethylene vinyl acetate (EVA) blends and reported a significant reduction of the dispersed phase droplets size in the presence of only 3 wt.% of both types of silica.…”

Triblock copolymers–modified SBR/EPDM rubber blends

“…Therefore, homogeneous SBR rubber blends have been obtained by the aid of different compatibilizing agents in order to improve mechanical properties of the final product. 11,12 However, EPDM and SBR are incompatible and various compatibilizers have been utilized for improving homogeneity of EPDM/SBR blends, including EPDM–graft–styrene copolymer, 13 hydrocarbon resin, 14 and polyethylene terphthalate glycolysis products. 15 The effect of EPDM/SBR blend ratio, vulcanizing system, and filler type on the mechanical properties of the blends has been assessed.…”