Moisture absorption in polyamide-6 silicate nanocomposites and its influence on the mechanical properties

Efficient one-step melt-compounding of copolyetheramide/pristine clay nanocomposites using water-injection as intercalating/exfoliating aid

“…A characteristic structure of limited conformation is then created at the vicinity of the filler. Mechanical properties of this interphase strongly differ from the bulk polymer [67]. Increasing the NaMMT content improves the interphase volume and its contribution to the mechanical behavior of the whole material, as usually reported for intercalated/exfoliated nanocomposites [2,3,5,70].…”

“…Moreover, a decrease of the nanocomposite glass transition, justified by a plasticizing effect attributed to the alkylammonium ions modifying the clay, is also reported when the mineral content increases [3]. Besides, mechanism of polyamide nanocomposites plasticization is the same as for the unfilled polyamide [66,67]. PEBA/OMMT nanocomposite prepared with water injection exhibits a T g higher than that of the one prepared without water.…”

“…The water-prepared PEBA/OMMT nanocomposites are less plasticized by alkylammonium because of a steam stripping of the surfactant moieties throughout the degassing apertures. Detailed results of odours and volatile organic compounds (VOC) emission analyses performed on the processed materials are reported elsewhere [67]. One of the key points is that PEBA/ OMMT prepared without water injection emits much more odours and VOCs (coming from the alkylammonium or its decomposition products) than the corresponding nanocomposite prepared with water injection.…”

Influence of Hygrothermal Aging on Poisson’s Ratio of Thin Injection-Molded Short Glass Fiber-Reinforced PA6

“…If the specimen PA6 GF materials are exposed to climate conditions at temperatures >T g and at a high relative humidity, there will be different, parallel proceeding aging processes which influence one another. Firstly, an increase of mass occurs by absorption of moisture by the diffusion process, which is driven more by the concentration difference of the absolute amount of water between the environment and specimens than by the temperature [31,32]. Further, there is a post-crystallization, which is supported by the water absorption.…”

Probing polymer chain constraint and synergistic effects in nylon 6-clay nanocomposites and nylon 6-silica flake sub-micro composites with nanomechanics

“…9,10 In clay/nylon 6 nanocomposites, the glass transition temperature is usually unchanged or very close to that of the unfilled nylon. 6,11 It is not yet clear to what extent the improvements in stiffness in clay/polymer nanocomposites are predominantly due to the incorporation of a much stiffer clay filler or whether the filler improves the stiffness and creep resistance by interaction with the polymer matrix exerting a constraining effect on the polymer chains. To maximize their potential, ideally NC would be designed with synergistic benefits over the base polymer, but as yet, there have been no reports that have clearly shown that such an enhancement exists and contributes to the improved surface mechanical properties.…”