THERMAL BEHAVIOROF POLYURETHANE HYBRID THERMAL INSULATION
Purpose. The article presents results of the study of polyurethane hybrid thermal insulation. Such properties as flammability, linear thermal shrinkage as well as gasification process have been studied. Macrokinetic parameters and physical mechanism of material decomposition in air have been determined. The study object was an industrial sample of «FoamTech 1550» hybrid polyurethane thermal insulation made in South Korea. The research subject was thermal behavior of the selected material. Methods. During the research we used both standard experimental methods and an original methodology for studying the mechanism of material decomposition including experimental and computational parts. Findings. As a result of combustibility study, it has been determined that the material belongs to low- combustible materials of medium flammability. Heating the sample in a muffle furnace revealed that sample shrinkage takes place within a single stage with the temperature interval 300-400 °C. Research of the combined TGA / DSC analysis showed multistage character of material decomposition. Macrokinetic parameters (activation energy, pre-exponential factor) for 1-4 decomposition stages have been determined. The calculated macrokinetic parameters of thermal decomposition of the material have been used to assess the processes of sample gasificationand shrinkage. In order to do this, Thiele mass and thermal modules have been applied. It has been shown that decomposition of the material organic part occurs within the pores, and differs from decomposition of, for instance, wood. Shrinkage is explained by plasticization of the organic part after breaking the bonds between organic and inorganic substrates.Research application field. The obtained results can be used for mathematic modeling of fires involving mentioned materials. The results give the idea of the mechanism of material decomposition in a fire. It is important for comparing a new group of materials with the already known types of polymer thermal insulation in terms of their fire hazard and possible applications in building and construction. Conclusions. Thermal behavior of the new group of materials - hybrid organo-mineral thermal insulation materials - has been studied. The article is a continuation of the authors' work on the systematic study of thermal behavior of modern types of polymer thermal insulation.