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

Abstract

The role of iron(III) oxide (Fe 2 O 3) 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/Fe 2 O 3 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 Fe 2 O 3 were characterized by a high flame resistance. The undoubtable advantages of the proposed technology are its simplicity, low cost and incombustibility.

Curing Behaviors, Mechanical and Dynamic Properties of Composites Containing Chloroprene and Butadiene Rubbers Crosslinked with Nano-Iron(III) Oxide

“…The use of nano-iron(III) oxide enables the crosslinking of the blend containing chloroprene rubber and butadiene rubber. The CR/BR/nano-Fe 2 O 3 blend was characterized by the following vulcametric parameters: t 02 = 7.30 min, t 90 = 16.70 min, M min = 0.68 dNm, ΔM 30 = 5.93 dNm ( Table 6 , Figure 5 ) Comparing the properties of the CR/BR blends crosslinked with nano-Fe 2 O 3 to the properties of CR/BR/micro-Fe 2 O 3 composition [ 16 ], the positive effect of nano-Fe 2 O 3 was observed in the case of the scorch time. For the CR/BR/nano-Fe 2 O 3 sample, the value of this parameter was 7.30 min.…”

“…The use of nano-iron(III) oxide as a crosslinking agent for the CR/BR blends had a comparable effect on the crosslinking degree, as the use of the micro-sized iron(III) oxides. The equilibrium swelling value in toluene for CR/BR/nano-Fe 2 O 3 was 6.20 mL/mL, while Q v T value for the CR/BR/micro-Fe 2 O 3 was 5.97 mL/mL [ 16 ].…”

“…The use of the following metal oxides (Cu 2 O, CuO, or Fe 2 O 3 ) as a crosslinking agent also leads to the interelastomeric connection of chloroprene rubber with butadiene rubber. A detailed description of the CR/BR crosslinking mechanism using the other metal oxides has been described in our previous articles [ 16 , 17 , 18 ].…”

“…The stress at 100%, 200%, and 300% elongation for the unfilled CR/BR/nano-Fe 2 O 3 composition was 0.70, 0.99, and 1.28 MPa, respectively. The use of micro-sized iron(III) oxide had a comparable effect on these parameters Se 100 = 0.65 MPa, Se 200 = 0.96 MPa, Se 300 = 1.26 MPa) [ 16 ]. Other strength parameters also do not significantly depend on the type of iron(III) oxide used.…”

Manganese and Nickel Acetylacetonates as Curatives for Chloroprene Rubber Based on Heck’s Reaction

“…On the other hand, as candidates to commercialization, these accelerators still must undergo experimental toxicity studies, because the computational techniques are only appropriate for substances used in small quantities and are just used only as a guide to predict the toxicity of potential candidates. Another interesting approach was reported by Smejda-Krzewicka et al, who proved that CR may be effectively crosslinked with other metal oxides, such as tin oxide (SnO) [ 22 ], iron oxides (Fe 2 O 3 , Fe 3 O 4 ) [ 23 ], or copper oxides (Cu 2 O, CuO) [ 24 ]. All presented examples enabled the elimination of both ETU and ZnO by using lower content of the proposed metal oxides compared to the reference curing system containing 5 phr of ZnO and 4 phr of MgO.…”