Mechanical properties and blend compatibility of natural rubber –chlorosulfonated polyethylene blends

Abstract

Natural rubber (NR) was blended with chlorosulfonated polyethylene (CSM) with various formulation and blend ratios (NR/CSM: 80/20 -20/80, wt/wt). Rubber blends were prepared by using a two-roll mill and vulcanized in a compression mold to obtain the 2 mm-thick sheets. Tensile properties, tear resistance, thermal aging resistance, ozone resistance, and oil resistance were determined according to ASTM. Compatible NR/CSM blends are derived from certain blends containing 20 -30% CSM without adding any compatibilizing agent. Tensile and tear strength of NR-rich blends for certain formulations show positive deviation from the rule of mixture. Thermal aging resistance depends on formulation and blend ratio, while ozone and oil resistance of the blends increase with CSM content. Homogenizing agents used were Stuktol60NS and Epoxyprene25. Stuktol60NS tends to decrease the mechanical properties of the blends and shows no significant effect on blend morphology. Addition of 5-10 phr of epoxidized natural rubber (ENR, Epoxyprene 25) increases tensile strength, thermal aging resistance, and ozone resistance of the blends. It is found that ENR acts as a compatibilizer of the NR/CSM blends by decreasing both CSM particle size diameter and ␣ transition temperature of CSM.

Improved Automotive Fuel Resistance of Natural Rubber/Chlorosulfonated Polyethylene Blends by Blending Epoxidized Natural Polymer

“…This was due to insufficient epoxidized molecules to bond between NR and CSM molecules. This result was similar to previous report [7]. The hardness of pure NR cured specimen was found to be ca.…”

“…Owing to the presence of the polarity of the chlorine group in CSM, NR/CSM blends should be resistant to ozone, oil, heat, flame, and nonpolar chemicals. Based on chemical structure, the NR/CSM blend may result in materials with inferior mechanical properties owing to the incom-patibility arising from the difference in polarity [7,8]. This result was the same as blended NR with higher polarity such as fluoro elastomer [9].…”

Evaluation of spectral, thermal, flame retardant, dielectric, solvent diffusion, and transport behavior of novel nanocomposite derived from chlorinated styrene butadiene rubber and manganous tungstate

“…The main disadvantage of solution mixing is the poor dispersion of nanoparticles and inability to remove trace of solvent completely, which limits the applicability of the solution mixing in industrial sector. Even though the melt mixing technique is effective to produce good filler dispersion, the higher temperature involved in the process causes deterioration in mechanical properties . Compared to these methods, a simple two roll mill mixing technique offers many advantages such as satisfactory filler dispersion, the absence of any organic solvent, the moderate temperature during mixing, and time‐saving factor .…”

Properties of Natural Rubber Filled with Ultra Fine Acrylate Rubber Powder

“…In addition, the thermal stability of NR is fairly poor due to its highly unsaturated structure. To overcome such shortcomings, many attempts have been made by blending NR with synthetic rubbers such as chlorosulfonated polyethylene (CSM), acrylate rubber (ACM), nitrile rubber (NBR), and chloroprene rubber (CR) [1][2][3][4][5][6][7]. It is widely known that there are many factors governing the blend properties including blend ratio and blend morphology [8][9][10].…”