Microstructure, Barrier Properties, and Mechanical ... Microstructure, Barrier Properties, and...

download Microstructure, Barrier Properties, and Mechanical ... Microstructure, Barrier Properties, and Mechanical

of 20

  • date post

    19-Feb-2021
  • Category

    Documents

  • view

    1
  • download

    0

Embed Size (px)

Transcript of Microstructure, Barrier Properties, and Mechanical ... Microstructure, Barrier Properties, and...

  • Microstructure, Barrier Properties, and Mechanical

    Properties of Nylon-12 Nanocomposite Films

    by

    Dr. Cecilia L. Stevens, Polymer Engineering Company

    Dr. Marek J. Gnatowski, Polymer Engineering Company

    Dr. Scott Duncan, Defence Research and Development Canada

  • Samples • Extruded films • 1.0 mil thick • 10% treated montmorillonite clay in nylon-12 • Various blending methods

  • Batch blending for 1 minute (B)

    REE 67 prep mixer with high-shear roller blades (W.C. Brabender)

  • Single-screw extrusion (C)

    25mm extruder with mixing screw, L/D = 25 (W.C. Brabender)

  • Twin-screw extrusion with compounding screws (D)

    D6-2 counter-rotating twin-screw extruder, L/D = 6 (W.C. Brabender)

  • Twin-screw extrusion with standard screws (E)

    TSE 20mm co-rotating twin-screw extruder, L/D = 40 (W.C. Brabender)

  • Methods of Assessment • Physical

    – Mechanical properties • Stress • Strain • Young’s modulus

    – Barrier properties • Breakthrough time

    • Structural – TEM imaging

    • Platelet size • Platelet exfoliation

    – FTIR spectroscopy

  • Observed Platelet sizes (nm)

    A (100% nylon-12) N/A

    B (batch blended) 202

    C (single-screw extrusion) 171

    D (compounding twin-screw) 144

    E (standard twin-screw) 111

  • Platelet exfoliation Batch blending (B)

  • Platelet exfoliation Single-screw extrusion (C)

  • Platelet exfoliation Compounding twin-screw (D)

  • Platelet exfoliation Standard twin-screw (E)

  • 100

    140

    180

    220

    260

    300

    100 120 140 160 180 200 220 Platelet size (nm)

    St ra

    in (%

    ) Mechanical properties

    Strain (%)

  • 20

    30

    40

    50

    60

    70

    80

    90

    100 120 140 160 180 200 220 Platelet size (nm)

    U lit

    m at

    e te

    ns ile

    s tr

    es s

    (M Pa

    )

    Mechanical properties Ultimate tensile stress

  • 0

    400

    800

    1200

    1600

    2000

    100 120 140 160 180 200 220 Platelet size (nm)

    Yo un

    g' s

    M od

    ul us

    (M Pa

    )

    Mechanical properties Young’s modulus

  • 0

    4

    8

    12

    16

    100 120 140 160 180 200 220 Platelet size (nm)

    B re

    ak th

    ro ug

    h tim

    e (h

    )

    Breakthrough time

  • 0

    0.2

    0.4

    0.6

    0.8

    1

    1.2

    100 120 140 160 180 200 220 Platelet size (nm)

    FT IR

    P ea

    k H

    ei gh

    t FTIR spectroscopy

  • FTIR example spectrum

    Nylon-12 peak used for normalisation of FTIR spectra Silicate peak

  • Conclusions • Platelet size starts to decrease prior to full

    exfoliation. • Prior to full exfoliation, mechanical properties

    are not highly responsive to platelet size (completeness of exfoliation).

    • After exfoliation, elongation at break is directly dependent on platelet size.

    • After exfoliation, stress and Young’s modulus are not highly responsive to platelet size, although improved over non-exfoliated samples.

    • Barrier properties are inversely related to platelet size both before and after exfoliation.

    • FTIR may be responsive to nanoclay dispersion.

  • Acknowledgements Polymer Engineering

    Company Dr. Marek Gnatowski pecltd@telus.net

    David Lesewick Beverley Start

    University of British Columbia TEM Kim Rensing Derrick Horne

    Defence Research and Development Canada Dr. Scott Duncan Scott.Duncan@drdc-rddc.gc.ca

    Ben Lacroix

    W.C. Brabender Andrew Yacykewych

    Suppliers Nanocor EMS-Grivory

    Microstructure, Barrier Properties, and Mechanical Properties of Nylon-12 Nanocomposite Films Samples Batch blending for 1 minute (B) Single-screw extrusion (C)� Twin-screw extrusion with compounding screws (D) Twin-screw extrusion with �standard screws (E) Methods of Assessment Observed Platelet sizes (nm) Platelet exfoliation�Batch blending (B) Platelet exfoliation�Single-screw extrusion (C) Platelet exfoliation�Compounding twin-screw (D) Platelet exfoliation�Standard twin-screw (E) Mechanical properties�Strain (%) Mechanical properties�Ultimate tensile stress Mechanical properties�Young’s modulus Breakthrough time FTIR spectroscopy Conclusions Acknowledgements