Poly 1,10-decamethylene-2,5-

The melting transition in polymers is conveniently observed by dilatometric measurements of the volume as a function of the temperature. Results thus obtained for poly-(N,N -sebacoyl piperazine) are shown in Fig. 129, and for poly-(decamethylene adipate) by the lowest curve in Fig. 130. Most of the melting, as evidenced by the abnormal increase in volume, occurs within a range of 10°, and it terminates abruptly at a temperature which may be defined within 0.5°. The data shown were obtained by raising the temperature... 

Noninteger values for n are not uncommon. As noted before, depending on the particular conditions several crystalline formations are possible and found for the same polymer. Sperling has collected a number of Avrami values for some common values given in the literature. The range of values for PE is 2.6-4.0 for poly(decamethylene terephthalate), 2.7. 0 for PP, 2.8-4.1 for poly(ethylene oxide), 2.0-4.0 and for iPP, 2.0-4.0. 

The critical chain length is often the onset of strength -related properties and is generally considered the lower end for useful mechanical properties. The Z value for polymers varies but is typically between 200 and 1000 units in length. For instance, the Z value for PS is about 700 for PIB about 600 for poly(decamethylene sebacate) about 300 for PMMA about 200 and for poly(dimethyl siloxane) about 1000. 

Poly(nonamethylene azelamide) (nylon 9,9) Poly(decamethylene azelamide) (nylon 10,9) Poly(decamethylene sebacamide) (nylon 10,10) 319/333 450 487 469/489... 

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