Изучение термической деструкции циклопропановых производных 1,2-СПБ

Using of the TGA (thermogravimetric analysis) and DSC (differential scanning calorimetry) methods thermal characteristics of cyclopropanoic derivants syndiotactic 1,2-polybutadiene (1,2-SPB) are studied. Temperature of the polymer decomposition beginning and temperature of its destruction for 1 and 5% of tentative weight were defined. Also, changes of mass of polymer when heating to 400 °C and heat effects of a destruction of cyclopropanoic polydiene are considered. Comparative assessment of thermal characteristics of syndiotactic polybutadiene in the environment of air and nitrogen is carried out. It is established that cyclopropanoic derivants 1,2-SPB differ in smaller heat stability in comparison with unmodified 1,2-SPB above 25 °C. In the environment of nitrogen thermal stability is shown stronger, than in the environment of air (40 °C higher). Change of mass of the studied polymer when heating to 400 °C increases in proportion to degree of its modification. The most intensive destruction of virgin syndiotactic polybutadiene and its cyclopropanoic derivants occurs in the field of temperatures of 400-500 °C that is caused by disintegration of carbon bonds in macrochains and formation of low-molecular weight compounds. It characterizes decrease in mass of polymer in some cases practically for 98% of initial weight. Influence of modification by 1,2-SPB cyclopropanoic groups on power consumption of polymer and possibility of using materials on its basis is established: introduction of cyclopropanoic groups to molecular composition of SPB considerably increases a polymer decomposition enthalpy (by 4 times in comparison with initial polymer) that allows to use the received polymeric products as power-intensive compositions and materials on their basis.