Mechanical Properties of Polyamides

Li Huang et al. [16] discussed the mechanical properties of polyamides. Lyons [17] obtained creep rupture data and tensile behavior for glass-filled polyamide and polyphthalamide at 2.3°C-150°C. 

Karayannidis et al. [18] studied crack propagation and impact strength of glass-reinforced polyamide 6,6 containing up to 12.5% of the functionalized triblock copolymer styrene (ethylene-co-butylene) grafted with maleic anhydride 

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The various mechanical properties of polyamides may be traced in many instances to the possibility of intermolecular hydrogen bonding between the polymer molecules and to the relatively stiff chains these substances possess. The latter, in turn, may be understood by considering still another equilibrium, this one among resonance structures along the chain backbone ... 

Table 2. Physico-mechanical properties of polyamide matrices filled with resite particles [141 ]...

In general, copolymers cross-link more readily than polyamide PA 66. Mechanical properties of polyamides are modified by irradiation, as seen by reduced tensile strength (50% loss when irradiated in air, 16% under vacuum). Aromatic polyamides retain strength better than aliphatic polyamides. ... 

Semenova SI, Belyakov VK, Smirnov SI, and Karachevtsev VG. Sorption and mechanical properties of polyamides in ammonia medium. In Transactions of the 3rd All-Union Conference on Membrane Methods of Separation of Mixtures, Cherkassy VNIISS, NDTEKhlM, 1981 77-82 (in Russian). 

B.Y. Shin, D.H. Han, Morphological and mechanical properties of polyamide 6/linear low density polyethylene blend compatibilized by electron-beam initiated mediation process. Radiat. Phys. Chem. 97, 198-207 (2014)... 

F.-C. Chiu, and I.-N. Huang, Phase morphology and enhanced thermal/ mechanical properties of polyamide 46/graphene oxide nanocomposites. Polymer Testing, 31 (7), 953-962,2012. 

Wahit, M. U., Hassan, A., Mohd Ishak, Z. A., and Abu Bakar, A. 2005. The effect of polyethylene-octene elastomer on the morphological and mechanical properties of polyamide 6/polypropyl-ene nanocomposites. Polymers and Polymer Composites 13 795-806. 

Zhang, L., Wan, C., and Zhang, Y. (2009) Investigation on morphology and mechanical properties of polyamide 6/ maleated ethylene-propylene-diene rubber/organoclay composites. Pdlym. Eng. Sd., 49, 209. 

Garcia-Lopez D, Femindez JF, Merino JC, Pastor JM (2013) Influence of organic modifier characteristic on the mechanical properties of polyamide 6/organosepiolite nanocomposites. Compos Part B Eng 45 459 65... 

The main factor promoting a change in the chemical composition and physico-mechanical properties of polyamides during photoaging consists of the photosensitized oxidative processes. 

Self-assembly of matter (or the formation of superstructures by means of non-covalent bonds) is a fascinating field of research. The formation of crystals and liquid crystals by atoms or molecules is just one example. Also within a larger molecule with a lot of conformational freedom, such as a polyamide chain or a protein, certain conformations are stabilized by secondary interactions, such as hydrogen bonds, which is essential for their properties (eg, mechanical properties of polyamides and functional properties of proteins). Secondary interactions in supramolecular structures play an important role for many processes in living cells (1). Various aspects of self-assembly have been presented in books (2-4) and in a recent review (5). This article deals with the self-assembly (or self-organization) of synthetic macromolecules, namely block copolymers, principally teming triblocks (see Block Copolymers). 

Dencheva N V, Oliveira M J, Pouzada A S, Kearns M P and Denchev Z Z (2011) Mechanical properties of polyamide 6 reinforced microfibrilar composites, Polym Compos 32 407-417. 

Jose Seno, Francis Bejoy, Thomas Sabu, and Karger-Kocsis J6zef. Morphology and mechanical properties of polyamide 12/polypropylene. Polymer. 47 no. 11 (2006) 3874—3888. 

N. A. Hocine, P. Mederic, and T. Aubry, Mechanical properties of polyamide-12 layered silicate nanocomposites and their relations with structure. Polymer Testing, 27 (2008), 330-39. 

Table 5 Mechanical properties of polyamide-based self-reinforced pol)oner composites, as described in the literature... 

After y-radiation sterilization at 25 kGy, the mechanical properties of polyamide 6 and 66 are not impaired. Colorless or white pigmented parts show light yellow discoloration. 

Figure 5.336 Change in mechanical properties of polyamide 11 caused by exposure to a glycol-water mixture at 40 and 70 °C Left fracture and tensile strength Right yield strain...

Many other physical and mechanical properties of polyamides, such as glass transition and heat distortion temperatures, melt viscocity, dimensional stability, flame retardancy, etc., are affected directly or indirectly by the addition of clay nano-layers but are not discussed here due to the defined scope and focus of this chapter. 

Ma C C M, Kuo C T, Kuan H C and Chiang C L (2003) Effects of swelling agents on the crystallization behavior and mechanical properties of polyamide 6/clay nano-coinposites, J Appl Polym Sci 88 1686-1693. 

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