Synthesis of α,ω-Di((N-ethyl)amino(2-methyl)propyl) Polydimethylsiloxane and Novel Siloxane-containing Epoxy Resin

α,ω-Di((N-ethyl)amino(2-methyl)propyl) polydimethylsiloxane (DEAMP-PDMS) together with siloxane-containing epoxy resin with different number average molecular weights, as reactive and functional polymers, were obtained through a three-step synthetic procedure. At first, α,ω-di((N-ethyl)amino(2-methyl)propyl) tetramethylsiloxane (DEAMP-TMS) was prepared by hydrosilylating tetramethyldi-siloxane with N-ethyl-2 methylallylamine in the presence of dihydrogen hexachloroplatinate catalyst. Then, DEAMP-PDMS was synthesized by a base-catalyzed equilibrium reaction of DEAMP-TMS with octamethylcyclotetrasiloxane (D4). Finally, a series of novel siloxane-containing epoxies (SEs) with different number average molecular weights were synthesized through ring opening addition reaction of DEAMP-PDMS with diglycidyl ether of bisphenol A epoxy (DGEBA). The structural elucidation of DEAMPPDMS and SE was carried out by FTIR, 1H NMR and 13C NMR spectroscopy methods. In addition, the purification methods and the factors influencing the synthetic process, such as reaction temperature, time, solvent, and catalyst as well as the relative amount of reactants utilized, are also discussed in detail. Number average molecular weight was determined by end group titration method. The results from spectroscopic analysis and end group titration show that the structure and number average molecular weights of target molecules are consistent with the designed molecular structure. As an advantage, the resultant SE exhibits good room-temperature mobility. Viscosity of SE decreases with the increase in number average molecular weights, which can be explained by the relative content of hydroxyl and the length of siloxane segment in SE.