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We prepared poly(vinyl alcohol) (PVA)/SiO 2 and PVA/SiO 2 /glutaraldehyde (GA) nanocomposite membranes in a single step using the solution casting method. The structure, morphology, and properties of these nanocomposite membranes were characterized by Raman spectroscopy, atomic force microscopy, small-and wideangle X-ray scattering, thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis (DMA). The influence of silica and GA loading on the meso-scale characteristics of the composite membranes was investigated. The results showed that silica deposited in the form of small nanoparticles (*1 nm) in the PVA/ SiO 2 membranes, while bigger submicron particles ([25 nm) were formed in the PVA/SiO 2 /GA membranes. The water uptake of the PVA/SiO 2 membranes increased with temperature, but the PVA/SiO 2 /GA membranes were completely dissolved above 50°C. We can therefore conclude that the addition of GA deteriorated the properties of PVA/SiO 2 membranes. The thermal stability of the PVA/ SiO 2 membranes increased with the increasing silica loading with a maximum char yield of 46 % for PVA/SiO 2 / 4T. Even DMA profiles indicated a promising increase in E R (rubbery modulus) from 6 MPa (PVA membrane) to 1015 MPa (PVA/SiO 2 /4T) at 250°C, showing high mechanical strength of these membranes.

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in inducing crazing and/or shear yield of the isotactic poly(propylene) (iPP) matrix. However, if the dimension of the rubbery domain in the iPP matrix is smaller than the size of the fracture ligament curvature then the rubbery domain is not able to stop the crack propagation. Thus, Jang et al. suggested that the optimal size of EPR domain is 0.5 μm. [ 2 ] The regular hiPP powder morphology (i.e., regular particle shape, narrow particle size distribution, homogeneous distribution of EPR phase in iPP matrix) contributes to the high reactor throughput and good hiPP powder processability. Many works focus on the morphology of the fi nal hiPP material in the molded or extruded form [3][4][5][6][7] but the characteristic application properties of hiPP are strongly infl uenced directly in the polymerization process. Although a number of papers dealing with the particle morphology after the fi rst (homopolymerization) stage [8][9][10][11] and after the second (copolymerization) stage [11][12][13][14][15][16][17] were published, important questions related to hiPP particle multiphase morphology and its evolution are still open. This paper reconstructs the principle of rubber incorporation in high impact poly(propylene) (hiPP) particles. The detailed information about the pores and rubber distribution inside and on the surface of hiPP particles is obtained by micro-computed tomography and atomic force microscopy. The strong effect of homopolymer origin on hiPP particle morphology and rubber distribution is demonstrated. To obtain the most homogeneous rubber distribution, the low homopolymer porosity is required. The initial particle porosity has a negligible effect on the thickness of the rubber layer on the particle surface at the medium rubber content. The rubber forms not only along the iPP primary particles and directly or close to the pores but also on or close to the particle surface rather than it fl ows there. The evidence for these claims is based on the systematic investigation in dependence on EPR content, homopolymer particle porosity (prepared by different catalysts) and antistatic agent deactivating catalyst close to particle surface.