Expert Vision for a Changing World AFM Applications for Polymer and Particle Systems Michael P. Mallamaci, Ph.D. PolyInsight LLC 526 South Main Street, Suite 414 Akron, Ohio 44311 (330) 777-0025 mike@polyinsight.com http://polyinsight.com
Agenda • Brief History of PolyInsight • Atomic-Force Microscopy (AFM) – Surface characterization technique – Internal structure technique • Using AFM in Cosmetic Science – Particulate gels in polymer modifiers – Surface structure of different nail polishes – Surface structure of human hair – Internal structure of human hair • Summary / Q & A Society of Cosmetic Chemists February 16, 2010 Slide 2 of 30 Lake Erie Chapter
PolyI nsight • Small team of experts in the physical and chemical structure of rubber and plastics • Laboratory operation with several microscopes and related sample preparation equipment in-house • Located in Akron, Ohio at the Akron Global Business Accelerator • Partnerships with The University of Akron and other regional laboratories providing additional instrument access Society of Cosmetic Chemists February 16, 2010 Slide 3 of 30 Lake Erie Chapter
PolyI nsight (cont’d) • Continuous operation since July 2003 • Services include: – Failure Analysis – Atomic-Force Microscopy (AFM) – Polymer and Chemical Analysis – Consulting and Litigation Support • Developed a portfolio of over 50 clients nationally and overseas • Medical/Healthcare, Automotive, Industrial Coatings, and Consumer Products Society of Cosmetic Chemists February 16, 2010 Slide 4 of 30 Lake Erie Chapter
Atomic-Force Microscopy (AFM) • High spatial resolution imaging of surface topography • Similar to stylus profilometry, except 1 nm resolution • Probe interacts with surface to reveal mechanical properties at high resolution Society of Cosmetic Chemists February 16, 2010 Slide 5 of 30 Lake Erie Chapter
Atomic-Force Microscopy (AFM) Change in amplitude Lag in phase related Change in amplitude Lag in phase related provides topography to viscoelasticity provides topography to viscoelasticity or material stiffness or material stiffness Free amplitude = A A o Free amplitude = o Damped amplitude at Damped amplitude at setpoint S = A A s setpoint S = s A o A A s A o s Phase lag Society of Cosmetic Chemists February 16, 2010 Slide 6 of 30 Lake Erie Chapter
Atomic-Force Microscopy (AFM) Veeco Dimension 3000 AFM Veeco MultiMode AFM (large sample sizes) (highest spatial resolution) Society of Cosmetic Chemists February 16, 2010 Slide 7 of 30 Lake Erie Chapter
Surface Characterization via AFM • The height of surface features can be measured quantitatively with 0.1 nm resolution • Atomic step heights on crystals, DNA molecules, proteins, semiconductor lithography applications • Maximum height of features allowed is ~ 6 µm, so surfaces must be “smooth” Society of Cosmetic Chemists February 16, 2010 Slide 8 of 30 Lake Erie Chapter
Surface Characterization via AFM Roughness Analysis – Surface of Polymer Stent Society of Cosmetic Chemists February 16, 2010 Slide 9 of 30 Lake Erie Chapter
Surface Characterization via AFM NIST Gold – 30nm spheres Society of Cosmetic Chemists February 16, 2010 Slide 10 of 30 Lake Erie Chapter
Surface Characterization via AFM Nano-drug particles – unknown size Society of Cosmetic Chemists February 16, 2010 Slide 11 of 30 Lake Erie Chapter
Particle size analysis using Veeco Nanoscope software Society of Cosmetic Chemists February 16, 2010 Slide 12 of 30 Lake Erie Chapter
I nternal Structure via TEM • Classic technique for examining the structure of composite materials is Transmission-Electron Microscopy (TEM) • Materials must be thinned to ~ 100 nm or less to be electron transparent • Image contrast is based on either electron diffraction (crystalline materials) or mass-density (amorphous materials) Society of Cosmetic Chemists February 16, 2010 Slide 13 of 30 Lake Erie Chapter
I nternal Structure of Soft Materials via TEM • Sample preparation technique for obtaining electron transparent thin sections is cryoultramicrotomy • Mass-density image contrast is enhanced by using heavy-metal stains, such as RuO 2 or OsO 4 • TEM offers highest spatial resolution possible at < 0.1 nm, plus chemical ID techniques • Time-consuming sample preparation ($$$) • Difficulty with complex multi-component systems Society of Cosmetic Chemists February 16, 2010 Slide 14 of 30 Lake Erie Chapter
I nternal Structure of Soft Materials via AFM • Probe interaction with the surface can image “mechanical property” distribution with high spatial resolution (1-5 nm) • Cryoultramicrotomy must be used to expose the internal structure – cut open in cross-section and look at the surface • Relies on surface structure being representative of internal structure (just like polished sections) Society of Cosmetic Chemists February 16, 2010 Slide 15 of 30 Lake Erie Chapter
I nternal Structure of Soft Materials via AFM • Incompatible 4 component polymer blend can be imaged – PP (brightest) – PA (round, less bright) – PE (dark orange) – SEBS (black, surrounds PA) Society of Cosmetic Chemists February 16, 2010 Slide 16 of 30 Lake Erie Chapter
Review of AFM Capabilities • High spatial resolution imaging of surfaces • Quantitative measurement of surface roughness and particles on substrates • Imaging of internal structure based on mapping of mechanical properties • Complex structures can be imaged, no stains required • Environmental control possible: air, inert gas, temperature Society of Cosmetic Chemists February 16, 2010 Slide 17 of 30 Lake Erie Chapter
Using AFM in Cosmetic Science • Particulate gels in polymer modifiers – Appearance, processing • Surface structure of different nail polishes – Reflectivity, composition • Surface structure of human hair – Damage, deposits • Internal structure of human hair – Dyeing Society of Cosmetic Chemists February 16, 2010 Slide 18 of 30 Lake Erie Chapter
Particulate gels in polymer modifiers Society of Cosmetic Chemists February 16, 2010 Slide 19 of 30 Lake Erie Chapter
Particulate gels in polymer modifiers Society of Cosmetic Chemists February 16, 2010 Slide 20 of 30 Lake Erie Chapter
Particulate gels in polymer modifiers Good Bad Society of Cosmetic Chemists February 16, 2010 Slide 21 of 30 Lake Erie Chapter
Surface structure of different nail polishes Clear top coat Society of Cosmetic Chemists February 16, 2010 Slide 22 of 30 Lake Erie Chapter
Surface structure of different nail polishes “Metallic silver” pigment in top coat Society of Cosmetic Chemists February 16, 2010 Slide 23 of 30 Lake Erie Chapter
Structure of Hair Society of Cosmetic Chemists February 16, 2010 Slide 24 of 30 Lake Erie Chapter
Surface structure of human hair Deposit Scales Society of Cosmetic Chemists February 16, 2010 Slide 25 of 30 Lake Erie Chapter
Surface structure of human hair Society of Cosmetic Chemists February 16, 2010 Slide 26 of 30 Lake Erie Chapter
I nternal structure of human hair Cuticle Cortex Society of Cosmetic Chemists February 16, 2010 Slide 27 of 30 Lake Erie Chapter
I nternal structure of human hair Cortex Cuticle Society of Cosmetic Chemists February 16, 2010 Slide 28 of 30 Lake Erie Chapter
I nternal structure of human hair Cortex Society of Cosmetic Chemists February 16, 2010 Slide 29 of 30 Lake Erie Chapter
Summary • AFM has unique strengths as a high resolution microscopy technique • Routine use as a tool for cosmetic chemists is possible: can “see” things that other techniques cannot • Offers quantitative microscopic measurement tool for “soft” cosmetic systems Society of Cosmetic Chemists February 16, 2010 Slide 30 of 30 Lake Erie Chapter
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