Synthesis, characterization, processability, mechanical properties, flame retardant, and oil resistance of chlorinated acrylonitrile butadiene rubber

Nitrile rubber (NBR) has been extensively used in high oil resistance application such as in automotive seals and gaskets. Due to the poor mechanical strength of NBR, the performance of these produ...

Comparative evaluation of oil resistance, dielectric properties, AC conductivity, and transport properties of nitrile rubber and chlorinated nitrile rubber:

Curing and properties of chloroprene and butadiene rubber (CR/BR) blends cross-linked with copper(I) oxide or copper(II) oxide

The role of iron(III) oxide (Fe2O3) in the cross-linking process, structure and functional properties of chloroprene and butadiene rubber (CR/BR) blends was studied. The unconventional elastomeric blends containing chloroprene and butadiene rubbers of different mass ratios, cross-linked with iron(III) oxide, have been studied. It has found that the iron(III) oxide could be used as a cross-linking agent in CR/BR blend and the curing degree depends largely on the composition of the blends. These results indicate that the curing degree of the blends is increased with increasing amount of chloroprene rubber. It is very interesting to note that the addition of butadiene rubber to chloroprene rubber improved the mechanical properties of the resulting vulcanizates. The resulting CR/BR/Fe2O3 vulcanizates were characterized by good mechanical properties. Surprisingly, the selected vulcanizates containing chloroprene and butadiene rubbers had a 40% greater tensile strength compared to vulcanizates containing only chloroprene rubber. The amount of iron(III) oxide as the curing agent slightly affected the curing degree and mechanical properties of the resulting rubber materials. This should probably be linked to the interelastomer reaction between the chloroprene and butadiene rubbers occurring in the presence of iron(III) oxide at an elevated temperature. Interelastomer reactions between both elastomers may lead to improved homogeneity and miscibility of the test systems. Additionally, it has been found that the CR/BR blends cross-linked with Fe2O3 were characterized by a high flame resistance. The undoubtable advantages of the proposed technology are its simplicity, low cost and incombustibility.

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The role of iron(III) oxide in chloroprene and butadiene rubber blends’ cross-linking, structure, thermal and mechanical characteristics

Effect of antioxidants on aging of the chloroprene rubber/butadiene rubber (CR/BR) blends

Preparation of Dichlorocarbene Modified Butadiene Rubber and Its Thermal Properties

Dichlorocarbene modified butadiene rubber (DCBR) was prepared via the addition of the dichlorocarbene group in the presence of 2 phase transfer agents (cetyltrimethylammonium bromide and tetraethylammonium chloride). The effects of the reaction temperature and time, amount of dichlorocarbene precursor, and the type and amount of phase transfer agent on the chlorine content were investigated. The highest chlorine content (30%) in DCBR was obtained using 0.062 mol chloroform and 0.003 mol cetyltrimethylammonium bromide at room temperature for 19 hours although 27.9% was obtained after 12 hours. The kinetics of this dichlorocarbene modification was best described by the pseudo–first order rate law with 2 rate constants. For practical applications, the DCBR with chlorine contents of 10%, 20%, or 30% were blended with natural rubber (NR) and then vulcanized using the sulfur-curing system. Although the polarity of DCBR was increased, a good compatibility between NR and DCBR still existed, resulting in improved mechanical properties. The oil resistance, flame retardant, and ozone resistance properties of the NR/DCBR blend vulcanizates were enhanced compared to those of a NR/butadiene rubber blend vulcanizate, which was related to the amount of chlorine incorporated into the DCBR.

Tapanee Witinuntakit

Papers

Preparation of Dichlorocarbene Modified Butadiene Rubber and Its Thermal Properties

Dichlorocarbene modified butadiene rubber (DCBR): Preparation, kinetic study, and its properties in natural rubber/DCBR blend vulcanizates