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The effect of six halogen-free flame retardant (FR) formulations was investigated on the thermal stability of two low-density polyethylenes (LDPE) and one linear low-density polyethylene (LLDPE), by means of thermogravimetric analysis (TGA) under nitrogen and air atmosphere. The relative data were combined with flammability properties and the overall performance of the FRs was correlated with the type of branching in the polyethylene grades and to their processing behavior. The thermal degradation kinetics was further determined based on the Kissinger and Coats-Redfern methods. In terms of flammability, the addition of a triazine derivative and ammonium polyphosphate at a loading of 35 wt. %. was found to be the most efficient, leading to UL 94 V0 ranking in the case of the LDPE grade produced in an autoclave reactor.

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Self‐healing systems are a next‐generation technology that can offer autonomous crack repair and increase the service lifetime of a protective coating. Polymeric microcapsules containing healing agents can be used in that perspective and exhibit significant potential. In the current study, poly(urea‐formaldehyde) microcapsules containing an epoxy healing agent as core material were successfully prepared using in situ polymerization. The effect of different process parameters was studied in respect to microcapsules' characteristics, that is, morphology, particle size, encapsulation efficiency and thermal properties. Spherical microcapsules with either smooth or rough surface were obtained with a size ranging from 90 to 165 μm, controlled by the stirring rate during the emulsification stage. The encapsulation efficiency varied between 65–77% with no significant dependence on the process conditions. Finally, the stability of the microcapsules during storage was investigated at different conditions.