Impact modified polyamide-organoclay nanocomposites

Işık, Işıl
The effects of melt state compounding and addition order of ethylene-butyl acrylate-maleic anhydride (E-BA-MAH), ethylene-glycidyl methacrylate (E-GMA), ethylene-methyl acrylate-glycidyl methacrylate (E-MA-GMA) terpolymer and/or three types of organoclays (Cloisite® 15A, 25A and 30B) on morphology, thermal, mechanical and dynamic mechanical properties of polyamide-6 are investigated. XRD patterns show that the interlayer spacing for Cloisite® 15A remained unchanged; however it increased for the organoclays Cloisite® 25A and Cloisite® 30B in both polyamide-6/organoclay binary nanocomposites and in polyamide-6/organoclay/impact modifier ternary systems. TEM analyses indicate that exfoliated-intercalated nanocomposites are formed. Sizes of elastomeric domains in nanocomposites are larger than the domains in their corresponding blends. The MFI results show that incorporation of elastomer reduces the MFI, due to the formation of graft copolymer. Both storage and loss moduli and complex viscosity of polyamide-6 increase with organoclay addition. In DMA measurements, in rubbery region, all nanocomposites show higher storage modulus than the unfilled counterparts. In general, the organoclays increase tensile and flexural strength, Young’s and flexural modulus and elongation at break, but decrease the impact strength, on the contrary, the addition of elastomer has the opposite effect. Generally, Cloisite® 15A containing ternary nanocomposites have higher tensile, flexural and impact strength and Young’s and flexural modulus than the ternary nanocomposites prepared with Cloisite® 25A and Cloisite® 30B. In general, nanocomposites processed by adding all the ingredients simultaneously give higher tensile and flexural strength and modulus than the nanocomposites produced by other mixing sequences.
Citation Formats
I. Işık, “Impact modified polyamide-organoclay nanocomposites,” Ph.D. - Doctoral Program, Middle East Technical University, 2007.