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The objective of this study is to examine the role of polymerizable and unpolymerizable pendant group of surfactant in clay dispersion in diallyl phthalate (DAP) matrix and evaluate the mechanical properties of resulting nanocomposites. Results of X-ray Diffraction (XRD) and high magnification Transmission Electron Microscopy (TEM) indicate an intercalated morphology for both types of nanocomposites, while low magnification TEM results show better dispersion of clay tactoids in the nanocomposite formulated with organclay containing polymerizable terminal pendant group. The mechanical properties of nanocomposites with organoclay loading of 1, 3, 5 and 7 wt%, respectively, were determined by performing flexural measurements. The testing results show that the nanocomposite formulated with organclay containing polymerizable terminal pendant group has better flexural properties than that formulated with organoclay containing unpolymerizable pendant group.

Carbon nanotubes (CNTs) were incorporated into glass fiber/ vinyl ester resins composites to improve their mechanical and thermal properties, especially the interlaminar shear and longitudinal compressive strengths which are belong to the matrix-dominanted properties and much weaker than the fiber-dominated properties. In this study, a higher temperature initiator was added to improve the polymerization degree and raise the transition temperature (Tg). Mechanical testing indicated that by adding 0.4 wt% CNTs, the nano-filled composites attributed to 21%, 16%, 10%, and 8% improvement in interlaminar shear strength, compressive strength, tensile strength and flexural strength with respect to their counterparts without CNTs, respectively. Moreover, Thermogravimetric analysis (TGA) also exhibits approximately 14°C higher decomposition temperature than those of conventional composites.

The cure kinetics of Derakane 411-350, a kind of vinyl ester resin, and its suspensions containing multi-walled carbon nanotubes( MWCNTs) were investigated via non-isothermal dynamic scanning calorimetry (DSC) measurements. The results showed that incorporation of MWCNTs into vinyl ester resin excessively reduces polymerization degree and crosslinking density of vinyl ester resin. For suppressing the negative effect caused by nanotubes, the higher temperature initiator combined with the initiator MEKP was used. Dynamic-mechanical Behavior testing was then carried out on the cured sample in order to relate the curing behavior of MWCNTs modified resin suspensions to mechanical response of their resulting nanocomposites. It was revealed that nanocomposites containing MWCNTs possessed larger storage modulus values as well as higher glass transition temperatures (Tg) as compared to those without MWCNTs after using mixed intiators system to improve the degree of cure.

To examine the role of nanoclays in the enhancement of interlaminar shear strength (ILSS) of glass fiber reinforced diallyl phthalate (GFR-DAP) composites, the GFR-DAP laminates were manufactured by hand lay-up techniques using two nanoclays, DK2 and MHAB-MMT, respectively. Χ-ray diffraction (XRD) were conducted to characterize the morphology of the dispersed clay particles in the DAP matrix. The mechanical performances were characterized by flexural strength and LISS measurements. XRD scans shows that the clays disperse uniformly in the DAP matrix and form an intercalated structure with a basal spacing of 3.86 nm and 3.98 nm for DK2 and MHAB-MMT, respectively. Short beam shear tests show that only 2.5 wt% clay loading in DAP matrix increased the ILSS of resulting GFR-DAP laminates by 7.64% and 14.80% for DK2 and MHAB-MMT, respectively, with respect to the neat DAP. The fractured surfaces of resulting laminates were observed by scanning electron microscope (SEM).