Amorphous strengthening mechanism

Thus, amorphous regions of polymer, bounded by crystals, are macroreactors in which chain process of mechanodestruction and failure of material is being developed. Hence, decrease of the amount of polymer amorphous part will lead to strengthening of the fibre and improving its physico-mechanical characteristics. 

Stmctural aspects of components constituting low-density polyethylene/ ethylene-propylene-diene rubber (LDPE/EPDM) blends are studied in bulk and compared to the surface layer of materials. Solvation of a crystalline phase of LDPE by EPDM takes place. The effect is more significant for systems of amorphous matrix, despite a considerable part of crystalline phase in systems of sequenced EPDM matrix seems to be of less perfect organization. Structural data correlate perfectly with mechanical properties of the blends. Addition of LDPE to EPDM strengthens the material. The effect is higher for sequenced EPDM blended with LDPE of linear structure. 

For an amorphous polymer that is drawn at an elevated temperature, the oriented molecular structure is retained only when the material is quickly cooled to the ambient temperature this procedure gives rise to the strengthening and stiffening effects described in the previous paragraph. However, if, after stretching, the polymer is held at the temperature of drawing, molecular chains relax and assume random conformations characteristic of the predeformed state as a consequence, drawing wOl have no effect on the mechanical characteristics of the material. 

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