Double phase separation induced by polymerization in ternary blends of epoxies with polystyrene and poly(methyl methacrylate)
Double phase separation induced by polymerization in ternary blends of epoxies with polystyrene and poly(methyl methacrylate)
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DOI：
10.1021/ma000429a
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发表时间：
2001-03
期刊：
影响因子：
5.5
通讯作者：
M. Galante;J. Borrajo;R. Williams;E. Girard-Reydet;J. Pascault
中科院分区：
文献类型：
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作者：
M. Galante;J. Borrajo;R. Williams;E. Girard-Reydet;J. Pascault
以双酚a二缩水甘油酯醚（DGEBA）和4,4′-二氨基二苯基砜（DDS）、单分散聚苯乙烯（PS, 8.3 × 104 g/mol）和单分散聚甲基丙烯酸甲酯（PMMA, 8.86 × 104 g/mol）的化学计量混合物为基础，在恒温下聚合三元共混物。共混物中两种热塑性塑料（PS/PMMA比例不同）的总重量为8wt %，在135℃时最初是均匀的。当它们在此温度下聚合时，通过光透射可以清楚地观察到双相分离。当转化率接近0.08时，由于生成了富含ps的相，该体系变得乳白色；当转化率接近0.27时，发生了新的相分离过程，产生了富含pmma的相。TEM（透射电镜）观察证实了三种不同相的存在：环氧树脂基体，具有广泛尺寸分布的富ps颗粒和富pmma颗粒。部分PS颗粒被富pmma相包裹。
Ternary blends based on a stoichiometric mixture of diglycidyl ether of bisphenol A (DGEBA) and 4,4‘-diaminodiphenyl sulfone (DDS), monodisperse polystyrene (PS, 8.3 × 104 g/mol), and monodisperse poly(methyl methacrylate) (PMMA, 8.86 × 104 g/mol) were polymerized at constant temperature. Blends containing a total amount of 8 wt % of both thermoplastics (with different PS/PMMA ratios), were initially homogeneous at 135 °C. When they were polymerized at this temperature, a double phase separation was clearly observed by light transmission. At conversions close to 0.08, the system became opalescent due to the generation of a PS-rich phase; at conversions close to 0.27, a new phase separation process took place, generating a PMMA-rich phase. TEM (transmission electron microscopy) observations confirmed the existence of three different phases: the epoxy matrix, PS-rich particles with a broad size distribution, and PMMA-rich particles. Some of the PS particles appeared encapsulated by the PMMA-rich phase (cor...