• Korea-Australia Rheology Journal
• /
• v.16 no.3
• /
• pp.135-140
• /
• 2004

Morphological and rheological properties of the poly(methyl methacrylate) (PMMA) and polystyrene (PS) blends were studied by scanning electron microscopy (SEM) and advanced rheometric expansion system (ARES). From the SEM results, the PMMA-PS blends showed dispersed morphology and the particle size of the dispersed phase was quite small (0.1~0.6 $\mu\textrm{m}$ compared with other immiscible polymer blends. Values of the interfacial tension of the PMMA-PS blend were obtained from the Choi-Schowalter and the Palierne emulsion models using the storage modulus of the PMMA and PS, and found to be 1.0 and 2.0 mN/m, respectively. The interfacial tension between the PMMA and PS was also calculated from the Flory-Huggins polymer-polymer interaction parameter ($\chi$) and found to be from 0.98 to 1.86 mN/m depending on the molecular weight and composition. Comparing the values of the interfacial tension from the Flory-Huggins polymer-polymer interaction parameter and the values measured by oscillatory rheometer, it is suggested that the interfacial tension of the PMMA-PS blend obtained from the polymer-polymer interaction parameter are in good agreement with the values obtained by rheological measurements.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.204-204
• /
• 2006

The interfacial interaction along with microstructure and some properties of the polyimide(PI)/silica or polyimide/silsesquioxane hybrid nanocomposites will be discussed with reviewing recent publications including our own works. Poly(vinyl silsesquioxane) (PVSSQ), aminosilane (APS), and titania can effectively play vital roles to compatibilize the PI/silica hybrid composites by enhancing interfacial interaction or reducing agglomeration of large domains, which helps the formation of nanocomposites for the PI/silica hybrid system.

• Polymer(Korea)
• /
• v.28 no.6
• /
• pp.487-493
• /
• 2004

The distribution of particles, in the mixture of poly(ethyl acrylate-co-t-butyl acrylate) (PEB) emulsion polymer and silica nanoparticles, was determined mainly depending on the pH of the mixture. The weak interfacial interaction was responsible for the severe coagulation of silica particles and the irregular dispersion for these nanocomposites. Methacryloxypropyltrimethoxysilane (MPS) was used to modify both the polymer and the silica. The nanocomposites which were prepared with these modified components had finer dispersion of silica nanoparticles and core-shell morphology due to the strong interfacial interaction. The strong hydrogen bonds were identified for these nanocomposites with FT-IR. The nanocomposites having strong interfacial interaction showed the increased glass transition temperature, the decreased ΔC$_{p}$ , and the increased decomposition temperature of the polymer chains. polymer chains.

• Polymer(Korea)
• /
• v.27 no.4
• /
• pp.299-306
• /
• 2003

It is well known that the interaction and adhesion between the glass fiber (GF) and polymer matrix has a significant effect in determining the properties of fiber-reinforced materials. Therefore, it is one of important considerations to modify the surface of glass fiber with an appropriate sizing. We investigated the treatment method of glass fiber with coupling agent to improve the interaction of the interfacial region. The correlation between interfacial property and interphase microstructure was also examined in an attempt to realize a proper morphology at the glass fiber surfaces.

• Carbon letters
• /
• v.11 no.2
• /
• pp.102-106
• /
• 2010

In this work, the effect of aminized multi-walled carbon nanotubes (NH-MWNTs) on the mechanical interfacial properties of epoxy nanocomposites was investigated by means of fracture toughness, critical stress intensity factor ($K_{IC}$), and impact strength testing, and their morphology was examined by scanning electron microscope (SEM). It was found that the incorporation of amine groups onto MWNTs was confirmed by the FT-IR and Raman spectra. The mechanical interfacial properties of the epoxy nanocomposites were remarkably improved with increasing the NH-MWNT content. It was probably attributed to the strong physical interaction between amine groups of NH-MWNTs and epoxide groups of epoxy resins. The SEM micrographs showed that NH-MWNTs were uniformly embed and bonded with epoxy resins, resulted in the prevention of the deformation and crack propagation in the NH-MWNTs/epoxy nanocomposites.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2002.10a
• /
• pp.249-251
• /
• 2002

It is well known that the interaction and adhesion between the glass fiber(GF) and polymer matrix has a significant effect in determining the properties of fiber-reinforced materials. Therefore, it is one of most important to modify the surface of GF with an appropriate sizing. We investigated the treatment method of GF with coupling agent to improve the interaction of the interfacial regions, and then the correlation between interfacial property and interphase microstructure was examined in an attempt to realize a proper morphology around the GF surface.

• Macromolecular Research
• /
• v.13 no.4
• /
• pp.306-313
• /
• 2005

Surface modified nanofillers are often used as curative-cum reinforcing agents for functional polymers. The polymer nanofiller interaction depends on the curative systems used. In the present study the carboxylic group of the carboxylated nitrile elastomer participated in the reaction with Zn-ion coated nanosilica filler producing a type of ionomeric elastomer. The interaction at the molecular level thus produced a high modulus vulcanizate. In this case, the S and MBT system, as curative, had an edge over the MDA and DPG curative system. Interfacial adhesion was enhanced in the presence of Zn-ion-coated nanosilica filler associated with dynamic mechanical behavior. The inferior properties obtained in the case of the MDA and DPG curative system were due to the decreased reactivity of the silica surface, thus reducing interfacial adhesion.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2005.11a
• /
• pp.157-160
• /
• 2005

The surface energies and acid-base interaction between the untreated and treated Jute or Hemp fibers and different matrix compositions of polypropylene-maleic anhydride polypropylene copolymers (PP-MAPP) were investigated using dynamic contact angle measurement. The contribution of the acid-base property into the interfacial adhesion of the natural fibers/matrix systems were characterized by calculating the work adhesion coming from the acid-base interaction. On the other hand, microfailure mechanism of both single Jute and Hemp fiber bundles were investigated using the combination of single fiber tensile test and acoustic emission. Distinctly different micro failure modes of the different natural fiber/polypropylene systems wet ε observed using optical microscope and determined indirectly by AE and their FFT analysis.

• Korea-Australia Rheology Journal
• /
• v.13 no.3
• /
• pp.125-130
• /
• 2001

Block copolymers of PC-b-PMMA (polycarbonate-b-polymethylmethacrylate) and PC -b-SAN (polycarbonate-b-(styrene-c-acrylonitrile)), were examined as compatibilizers for blonds of PC with SAN copolymer. The average diameter of the dispersed particles was measured with an image analyser, and the interfacial properties of the blonds were analysed with an imbedded fiber retraction (IFR) technique. The average diameter of dispersed particles and interfacial tension of the PC/SAN blends reached a minimum value when the SAN copolymer contained about 24 wt% AN. Interfacial tension and particle size were further reduced by adding compatibilizer to the PC/SAN blends. PC-b-PMMA was more effective than PC-b-SAN as a compatibilizer in reducing the average diameter of the dispersed particles and interfacial tension of PC/SAN blend. A direct proportionality between the particle diameter and interfacial tension was also observed. The interfacial properties of the PC/SAN blends were optimized by adding a block copolymer and using an SAN copolymer that had minimum interaction energy with PC.

• Bulletin of the Korean Chemical Society
• /
• v.15 no.1
• /
• pp.45-52
• /
• 1994

We present a theoretical study of the non-symmetrical A/BC polymeric system. The polymer blends consist of two phases, a pure polymeric phase A on one side and a mixture of polymers B as a compatibilizer and C on the other. The adsorption of homopolymer B to the interface improves the interfacial adhesion between two phases. By employing the functional integral techniques, we derive the mean-field equations and solve them numerically to obtain the interfacial properties including the concentration profiles in the limit of infinite molecular weight for the polymers. Thecalculations of the interfacial properties are performed for typical values of the Flory X parameters and the volume fraction of polymer B in the asymptotic mixture phase. The interfacial adsorption of polymer B and the degrees of the specific interaction between the polymers play an important role in modification of the interfacial properties.