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Reduction of molecular weight of rubber polymers for easy absorption of compounding ingredients is critical in every rubber compounding operation. Yet, rubber mastication which is the current practice of achieving this is expensive, requiring high energy and equipment cost. To address this problem, microbial degradation of natural rubber (NR) and waste rubber tire (WRT) by Nocardia sp. strain 385A was studied using dilute solution viscosity measurement and weight loss methods. Solutions of NR and WRT in toluene were inoculated with the microbes (Nocardia sp. strain 385A) and kept in incubator. Incubation period varied between 0 to 10 weeks. The results obtained show that NR and WRT were mineralized and degraded by the microbes. Intrinsic viscosity values of both NR and WRT decreased with increasing period of incubation, indicating that degradation increases with increase in the incubation period. For the incubation periods investigated, WRT produced higher intrinsic viscosity values than NR due to the inhibitory effect of additives present in WRT to microbial degradation. Equivalent reduction in molecular weight obtained by rubber mastication technique was achieved by microbial degradation after 10 weeks incubation period. Rubber degrading bacteria can be useful for the disposal of discarded rubber products

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Recently, escalating quests for miniaturized gadgets and flexible electronics have induced huge electromagnetic wave deterioration and high risk of fire outbreak. Hence, the fabrication of ultra-light and flame retardant (F-R) polymeric nanoarchitectures (PNC) has become critical and challenging. MXene (M-X), an emerging two-dimensional (2-D) nanomaterial (NM) has demonstrated high potential for fabricating F-R flexible PNC. Regarding flammability repression, increasing inclusion of M-X within polymeric matrices has demonstrated propensity to notably suppress critical flammability parameters such as heat release rate (HRR), peak of heat release rate (PHRR), carbon monoxide production rate (COPR), smoke production rate (SPR) and total mass loss rate (TMLR) while simultaneously increasing limiting oxygen index (LOI), time of ignition (TOI) and total peak of heat release rate (TPHRR) and attainment of UL-94 V-0 rating. These achievements have effectively repressed flammability of MX-polymeric nanoarchitectures thereby offering higher opportunity to minimize loss and actual risks in real life fire situation through formation of MX char within the condensed phase thereby effectively repressing the heat decomposition induced by oxygen to the polymeric matrix, thereby cutting-off the fire pathway. Hence, PNC fabricated from emerging nanoparticulates such as 2-D M-X (Ti 3 C 2 Tx) have demonstrated prospects for manufacturing high-performance flame suppressing PNC. Therefore, this paper presents recently emerging trends in flame retardant efficiency of M-X polymeric nanoarchitectures and applications.