Preparation and some properties of nylon 46

Abstract

SynopsisNylon 46 was synthesized from the salt of l,4-diaminobutane and adipic acid. High molecular weight polymers could be obtained by reaction for 1 hr at 215OC in a closed system and at least for 1 hr in UQCUO at a temperature in the range 290-305OC. The reactions at 29OOC were found to have taken place in the solid state and those at 305OC in the melt. The highest molecular weights ( M , ca. 45,000) were obtained by reaction at 290°C with a nylon salt with a pH of 7.8-8.0. The molecular weight characteristics were studied with end-group analysis, viscometry, light scgtering, and ultracentrifugation. The polymers were found to be gel-free and monodisperse (M,/Mn -1.15).Films could be cast from formic acid. From x-ray diffraction patterns, measured on such films, spacings of 3.74 and 4.30 A were calculated, whereas a long period of 66 A was also found. The infrared spectra showed all the usual amide bands of even-even polyamides. The melting temperature was found to vary between 283 and 319OC, depending on the thermal history of the sample. Water absorption measured on a cast film showed this to be very hygroscopic (7.5% at 65% RH), while a highly crystalline sample absorbed only little water (1.6% at 65% RH).

Application of continuous zone-drawing/zone-annealing method to poly(ethylene terephthalate) fibers

“…tallites. 29,30 Figure 6 shows the temperature dependence of Mechanical Properties for the CZD and CZA Fibers thermal shrinkage for the original, CZD, and CZA Table IV lists the tensile properties of the CZD, fibers. Development of the thermal shrinkage dur-CZA, ZD, and ZA fibers.…”

Mechanical properties and superstructure of poly(ethylene terephthalate) fibers zone‐drawn and zone‐annealed by CO2 laser heating

“…30 A sharpening of the melting peak with the processing is caused by an increase in the degree of perfection of the crystallites. 31,32 Mechanical Properties for the LH-ZD and LH-ZA Fibers Table III lists the tensile properties of the original, LH-ZD, and LH-ZA fibers. The tensile properties tend to increase stepwise with increasing processing.…”

Polyamides

“…A product with a narrow molecular mass distribution was obtained by SPP of 46-salt at 290 C [120]. Prepolymerization in the presence of water followed by SPP yields a commercial quality product [121,122].…”