Studies on the Properties of Nylon Plastics (Part 1)

Abstract

The rate and saturation value of water absorption were determined for nylon plastics molded in different shapes by injection molding. The degrees of crystallinity and its distribution in the specimens were estimated.The change of dielectric properties caused by water absorption and the degree of crystallinity were measured in a frequency, ranging from 50KC/sec to 20MC/sec. Behavior of the absorbed water and mechanism of polarization were discussed.The results are summarized as follows: 1) Water absorption gets larger in the order of nylon 610, 66, 6, 6/66 copolymer, and decreases by containing some additives such as graphite or metal powder.2) Water content of nylon is proportional to the 0.4-0.5th power of time, independent of the kind of nylon, the shape of specimen, the relative humidity, etc.3) The average degree: of crystallinity gets smaller in the order of nylon 66 (37.8%), nylon 610 (30.4%), nylon 6 (24.7%).4) The dielectric properties of nylon containing water are in non-linear relation with water content.5) At a definite temperature and a definite degree of crystallinity, the higher the water content is, the smaller the internal friction for polar groups to orientate, which the internal friction for polar groups becomes larger with the increase of crystallinity.

Stress‐strain behavior of polychloroprene vulcanizates containing polymer‐gel particles

“…Therefore, one obtains the following equation for a case of no adhesion between the blend phases. a( a ) = (1 -+"'")aR( a ) (1) where a( a ) is the stress of a blend at elongation ratio a, OR( a ) the stress of a matrix at a, 4 the volume fraction of gel sphere.…”

“…This result shows the value of the mode proposed here. The tensile strength of polychloroprene vulcanizates filled with polychloroprene-gel at break is discussed by the use of Eqs 2-4. INTRODUCTION echanical properties of polymer blends have M. been established both experimentally and theoretically within the linear region (1). On the other hand, morphological analysis allows one to investigate the deformaticn of the blend component, compared to mechanicaI analysis ( 2 ) .…”