Thermal degradation studies of poly(urethane–siloxane) thermosets based on co-poly(dimethyl)(methyl, 3-glycidoxypropyl)siloxane and epoxy-terminated urethane oligomer

Synthesis and properties of photopolymerizable bifunctional polyether-modified polysiloxane polyurethane acrylate prepolymer

“…The initial decomposition temperature (T 5% ) can be considered as the temperature at which the weight loss was approximately 5 wt%, and T max corresponds to the temperature of the maximum decomposition rate. [21,22] For the cured films with HEA or TMPTA, only one DTG peak can be observed during the single-step thermal degradation process with the temperature of the maximum decomposition rate at 412 °C for PESiUA-HEA and 455 °C for PESiUA-TMPTA. The thermal degradation processes of the UV-cured films with TPGDA underwent single-step degradations with two DTG peaks at 377 °C (T max1 ) and 421 °C (T max2 ).…”

Thermal and surface properties of hybrid materials obtained from epoxy-functional urethane and siloxane

“…The PSi samples reveal larger thermal stability comparing to similar materials but obtained from PTMO with M n = 1000, which is reflected in lower T 5 % for the latter [19]. The difference in temperature of 5 % weight loss for both sample series exceeds 10°C.…”

“…However, a detailed analysis of DTG curves revealed the presence of shoulder peak in temperature range of 300-350°C for the samples with 50 wt% of siloxane, whereas for PSi75 % the first step of degradation is not observable in temperature range of 205-370°C. This may suggest a more complex mechanism of thermolysis at first decomposition stage, involving degradation of siloxane moieties, as well [19]. The mass loss at this stage decreases from 19.0 to 11.0 with a decrease of urethane segments, which additionally indicates the scission of urethane bonds at this step.…”

“…The mass loss at this stage decreases from 19.0 to 11.0 with a decrease of urethane segments, which additionally indicates the scission of urethane bonds at this step. The second stage of degradation occurs in the range of 360-580°C and is related to the degradation of soft PTMO segments as well as thermo-stable siloxane moieties [19]. The temperature of the maximum rate of weight loss at this stage decreases, whereas the mass loss residue increases from 82.5 (PSi25) to 92 % (PSi75) with the increased siloxane contribution.…”

“…The first step is related to urethane bond scission and formation of carbon dioxide [20]. The second step involves scission of PTMO as well as siloxane segments [19]. In this stage two mechanisms of siloxane decomposition are probable: a molecular mechanism with formation of cyclic oligomers and a radical one occurring through homolytic Si-CH 3 bonds scission [21].…”