Thermal degradations of chlorinated natural rubber from latex and chlorinated natural rubber from solution

Abstract

The thermal degradations of chlorinated natural rubbers from latex (CNR-L) and from solution (CNR-S) under nitrogen atmosphere were studied with thermogravimetric analysis (TGA). The thermal degradations of CNR-L and CNR-S are one-step reaction. The shapes of the thermogravimetric and derivative thermogravimetric curves are similar. The degradation temperatures of CNR-L and CNR-S increase linearly with the increment of heating rates. The heating rate hardly affects the thermal degradation rates of CNR-L and CNR-S at the various degradation stages. The thermal degradations of CNR-S and CNR-L are dehydrochlonation reactions. The reaction activation energy (E) of CNR, at the first stage, is around 100 kJ/mol. After that, E remains relatively steady (80-140 kJ/mol). At the last stage, E rises rapidly (130-270 kJ/mol). The variation tendency of frequency factor (A) is similar to that of E. As the initial degradation temperature T 0 of CNR-L is 10.98C lower than that of CNR-S, the thermal stability of CNR-S is better than that of CNR-L, which may be caused by the difference of molecular structure between CNR-L and CNR-S, as FTIR results indicate that there are more À ÀOH, À ÀC¼ ¼O and À ÀCOOÀ À groups in the CNR-L molecular chains.

Comparative studies on mechanical properties and dehydrochlorination of chlorinated natural rubber-based composites containing carbon nanotubes and graphene through DFT and experiments

“…It was noted that the pure CNR also had a weight loss of about 5% at 200°C, which was consistent with the experimental results reported in the literature [40]. This weight loss at 200°C was attributed to the dehydrochlorination reaction of CNR [40,41]. And, the weight loss of the CNR/graphene composite (or the CNR/ CNT composite) at 200°C reached 6.4% (or 8.9%), which was slightly higher than that (5%) of pure CNR.…”

Chlorinated reclaimed rubber: preparation, structure and performance

“…Generally, the first ones are around 200°C, and the second ones are around 414∼420°C. Referred to previous documents (Cai et al , 2007; Gamage et al , 2009), the former peaks of decomposition are ascribed to decomposition of C-Cl bonds, and the later are resulted from decomposition of C-H and C-C bonds. In a word, the heat resistance of chlorinated RR is poorer than raw RR, which implies that proper heat stabilizer must be incorporated into chlorinated RR when it is further fabricated.…”

Insights into structural, thermal, electrical and mechanical properties of copper alumina reinforced chlorinated natural rubber nanocomposites

“…Among the various chemical modifications reported, chlorinated derivatives of NR have shown excellent solvent and oil resistance in addition to good thermal properties. 12,13 Optimum chemical and physical properties are obtained by controlled chlorination of NR with special attention to the time and extent of chlorination. Halogenated polymers are widely used in engineering applications due to their high mechanical and dielectric properties, resistance to chemicals, oils and increased flame retardancy and adhesive nature.…”