| Summary: | 碩士 === 國立臺灣科技大學 === 化學工程系 === 105 === Synthesis of nano-scale or submicron-scale general prepose core-shell rubber (gp-CSR) and nano-scale reactive microgel particles (RM) by conventional emulsion polymerization with or without surfactant as low-profile additives (LPA) and tougheners for unsaturated polyester resins (UP) and vinyl ester resin (VER) have been investigated. Two types of UP with different chemical structures, namely, MA-PG and MA-PA-PG, as well as epoxy resin (EPR) and vinyl ester resin (VER) with degree of polymerization (n) = 0.16, 2, and 5, have also been synthesized so that styrene (St) /VER /CSR ternary systems with different miscibility can be designed.
For the synthesis of nano-scale gp-CSR, the core was made from PBA, the shell was made from poly(methyl acrylate)(PMA). For submicro-scale gp-CSR, the core was made from PBA, the shell was made from poly(methyl methacrylate) (PMMA). Futhermore, the shell of the CSR was modified by 5~15 mole percent of glycidyl methacrylate (GMA) as a comonomer to increase the molecular polarity and provide the specific functionality, such as epoxy group, for the shell of the CSR.
For the synthesis nano-scale reaction microgel particles,two comonomers,including styrene (St) and unsaturated polyester (UP),were employed. Conventional emulsion polymerizations, which involved the addition of sodium dodecyl sulfate as a surfactant and 1-pentanol as a co-surfactant, along with the adjustment of PH value during the polymerization to facilitate a self-emulsifying copolymerization a simultaneous reaction of St and UP were carried out. By varying the molar ratio of styrene to UP C=C bonds (MR), reactive microgels with diameters ranging from 30nm to 100nm have been synthesized. As to the UP resine used as the monomer, it was made from maleic anhydride(MA) and 1,6-hexanediol(HD) by polycondensation in bulk at our laboratory.
By conducting phase separation experiments and employing Debye’s equation, the dipole moments of UP, VER, EPR, the shell component of the CSR, and RM can be calculated, and the phase characteristics of the St/VER/CSR and St/VER/RM ternary systems have been elucidated. Finally, the volume shrinkage characteristics and mechanical properties of the St/VER (n=2)/CSR ternary system after cure have also been explored.
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