| Polymer polyether polyol composites (PPOCs), which are stable dispersions of glassy polymers in polyether polyols, provide a feasible method for particle reinforcement of polyether materials. In this work, the PPOC with high solid content of 45% were prepared by dispersion copolymerization of styrene (St) and acrylonitrile (AN) in polyether polyols with macromonomer as a stabilizer precursor in both semi-batch and continuous processes. The characters of formation, stability and viscosity of the dispersion were studied. Preparing conditions for stable PPOC with low viscosity and high solid content were opimized. Moreover a hydrophilic PPOC was used to prepare polyether polyurethane hydrogels in order to realize particle reinforcing hydrogels.For the purpose of examining the effect of structure of macromonomers on their stabilizing ability for the PPOC, various macromonomers (MM) were synthesized by reacting polyether with various relative molecular mass (RMM) with maleic anhydride at different temperature or fumarate monoethyl chloride, and their stabilizing abilities were evaluated. The results showed that the RMM and terminal unsaturated structure of MM and the miscibility of MM with the dispersing medium (polyether) were the crucial factors for the stabilizing ability of MM. Therefore, a novel macromonomer (HFM) was synthesized through polyether extending reaction with toluene diisocyanate (TDI) and then reacting with fumarate monoethyl chloride. Using HFM as a stabilizer precursor, the effects of polymerization parameters on stability and viscosity of PPOCs were investigated in semi-batch, seeded-batch and continuous processes, respectively, while the corresponding particle shape and size distribution were determined by SEM and dynamic light scattering. The results indicated that the content of HFM and the relative ratio of polymerization in continuous phase and in particle phase played important roles on the stability of PPOC. The rheological behavior of the PPOC revealed that the particle size and distribution were the key factor for controlling the viscosity of PPOC and its non-Newtonian behavior without particle aggregation, because too much small particles increase the viscosity of PPOC. So PPOC with low viscosity can be obtained in two-reactor continuous process, which can produce PPOC with large particle size with wide distribution. By optimizing, the PPOC with solid content of 45% and viscosity of 5500-6000mPa.s was obtained. The stabilizer, graft polymer PSAN-g-polyether, formed in situ was separated by a full-adsorption-desorption liquid-solid chromatograph method (FAD), and characterized by UV and NMR. Combined with the change profile of particle size in the formation process of the dispersion determined by dynamic light scattering, it is proved that the nucleation mechanism of aggregation of graft polymer is dominant in the semi-batch polymerization process.A hydrophilic PPOC was prepared by polymerizing St and AN in a trifunctional copolyether of ethylene oxide (EO) and propylene oxide with EO content of 78wt%. By reacting this PPOC with TDI and polyether diols, reinforced polyether polyurethane hydrogels were prepared. The effect of NCO index and the particle (PSAN) content on the degree of swelling (DS) in water and mechanical properties of the hydrogels were investigated. The data showed that there is effective particle reinforcing effect in both xerogel and hydrogel states. Increasing the PSAN particle content resulted in both increase in tensile strength and maximum elongation either for the xerogels or for hydrogels, meantime DS of hydrogels decreased. By adjusting the NCO index and the incorporated PSAN particle content, a reinforced polyether hydrogel was synthesized, it has an elongation of 120% and tensile strength of 0.75MPa at DS of 250%, while the polyether polyurethane hydrogel at the same DS exhibits elongation of 42% and tensile strength of 0.22MPa.
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