Thermal Properties and Crystallite Morphology of Nylon 66 Modified with a Novel Biphenyl Aromatic Liquid Crystalline Epoxy Resin
School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China
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Int. J. Mol. Sci. 2013, 14(10), 20682-20691; https://doi.org/10.3390/ijms141020682
Received: 19 August 2013 / Revised: 23 September 2013 / Accepted: 30 September 2013 / Published: 15 October 2013
(This article belongs to the Special Issue Experimental and Theoretical Studies of Liquid Crystalline Materials: Where Do We Stand after 120 Years?)
In order to improve the thermal properties of important engineering plastics, a novel kind of liquid crystalline epoxy resin (LCER), 3,3',5,5' -Tetramethylbiphenyl-4,4' -diyl bis(4-(oxiran-2-ylmethoxy)benzoate) (M1) was introduced to blend with nylon 66 (M2) at high temperature. The effects of M1 on chemical modification and crystallite morphology of M2 were investigated by rheometry, thermo gravimetric analysis (TGA), dynamic differential scanning calorimetry (DSC) and polarized optical microscopy (POM). TGA results showed that the initial decomposition temperature of M2 increased by about 8 °C by adding 7% wt M1, indicating the improvement of thermal stability. DSC results illustrated that the melting point of composites decreased by 12 °C compared to M2 as the content of M1 increased, showing the improvement of processing property. POM measurements confirmed that dimension of nylon-66 spherulites and crystallization region decreased because of the addition of liquid crystalline epoxy M1.