FROM NANOPARTICLES TO ADVANCED MACRO APPLICATIONS

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FROM NANOPARTICLES TO ADVANCED MACRO
APPLICATIONS

• The 4th International Conference on
• NANOTECHNOLOGY FOR THE
• PLASTICS RUBBER INDUSTRIES
• February 2, 2009

Shenkar College of Engineering Design
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NANO - POSS ENHANCED POLYMER ADHESIVES

• Dr. Ana Dotan
• Prof. Hanna Dodiuk
• Plastics Engineering
• Shenkar

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Nano enhancement How?

• The small nano particles presents an enormous
  surface area
• The potential of using nano fillers for
  enhancement of adhesive properties is promising
  provided
• agglomeration is avoided
• good interfacial bonding
• is obtained

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Nano structuring methodology
The large surface area of nano particles
(hundreds of m2/gr.) leads to interaction with
polymer molecules in the nano level
Functionalization of the nano particles surface
leads to chemical reactions in reactive polymer
systems (thermosetting)
Nano Structured Adhesives Composites
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Objectives

• Study the effects of
• POSS functionalities
• nano structure of adhesives
• macro properties of adhesives

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Polyhedral oligomeric silsesquioxanes

• The name silsesquioxane comes from the sesqui,
  which means one and a half
• General formula (RSiO1.5)n - 1.5 oxygens for
  each silicon
• The suffix ane represents a hydrocarbon group,
  R.
• The term polyhedral indicates
• the cage or polyhedron
• nature of the (RSiO1.5)n core.

http//matdl.org/matdlwiki/index.php?titlesoftmat
terPOSS
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POSS
POSS chemical composition is a hybrid,
intermediate (RSiO1.5) between that of silica
(SiO2) and silicone (R2SiO). POSS molecules can
be thought of as the smallest particles of silica
possible.
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Structure of silsesquioxane
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Dimensions and functionality
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• non reactive end
• groups

• partial
• functionalization

• many reactive
• end groups

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3-(Aminoethyl)amino)propyl-Heptaisobutyl
substituted
POSS Functionalities
2-(3,4-Epoxycyclohexyl)ethyl)-Heptisobutyl
substituted
Octaphenyl substituted
Glycidoxypropyldimethylsilyloxy- Heptacyclopentyl
substituted
isocyanatopropyldimethylsilyloxy
Heptacyclopentyl substituted
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POSS nanocomposites

• The incorporation of POSS cage structure into
  polymeric networks often results in dramatic
  improvements in polymer properties
• increase in use temperature
• oxidation resistance
• surface hardening
• improved mechanical properties
• reductions in flammability and heat evolution

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Dispersion nanostructure of POSS in polymer
matrix
POSS agregates
Top row Electron energy filtered (EF)
compositional images of C and Si. Bottom row
combined SiC elemental map, Si/C elemental map,
and a conventional non-EF bright field image.
POSS molecules are Si rich compared to the
polymer matrix which is C rich compared to POSS
molecules.
http//www7430.nrlssc.navy.mil/facilities/emf/nano
comp.htm
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Epoxy-POSS nanocomposites
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Epoxy adhesives
Curing Conditions Stoichiom. Curing Agent Epoxy Charact.
80oC for 8 hrs 7030 w/w polyamidoamine Versamid 140 diglycidyl ether of bisphenol A (DGEBA) Low temp.
150oC for 12 hours 66/34 w/w Polyoxypropylene diamine (Jeffamine D-230) Tetraglycidyl diamino diphenyl methane (TGDDM) Medium temp.
150oC for 12 hours 57/43 w/w Polyoxypropylene triamine (Jeffamine T-403) Tetraglycidyl diamino diphenyl methane (TGDDM) High temp.
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Methodology

• Nano structuring of epoxy adhesives by a variety
  of functionalized POSS particles
• Effect on bulk adhesion properties

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Experimental

• Analysis methods
• Dynamic Mechanical Analysis (DMA)
• Lap shear strength ASTM D-1002. Aluminum
  adherends unsealed chromic acid anodization
• Peel strength ASTM D-1876. Aluminum adherends
  unsealed chromic acid anodization

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Results
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Tg of POSS/Low temp. EPOXY
Tg(c)
Tg increases in the range of 2-5 Wt. of POSS
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Tg of POSS/Med. temp. EPOXY
Tg increases in the range of 0.5-1 Wt. of POSS
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Tg of POSS/High temp. EPOXY
Tg increases in the range of 2-3 Wt. of POSS
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EFFECT OF POSS ON STORAGE MODULUS at 25 oC Low
temp. Epoxy
Highest effect at low concentration of reactive
POSS
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The Effect of POSS on Storage Modulus at
25oC Med. temp. Epoxy
Highest effect at low concentration of POSS
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The Effect of POSS on Storage Modulus at
25oC High temp. Epoxy
Highest effect at low concentration of POSS
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Low temp. EPOXY/POSS ADHESIVES Shear and Peel
Strengths
Weight concentration at maximum Tg
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High temp. epoxy/POSSPeel Strength
Best results for amino, glycidoxy epoxy POSS
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High temp. epoxy/POSSShear Strength
Best results for 3 Amino POSS No significant
increase in SS
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Polyurethane-POSS nanocomposites
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POLYURETHANE ADHESIVES

• Materials
• Trifunctional polypropylene polyether polyol
  (Desmophen 1380 BT, Bayer, Germany)
• Linear polypropylene ether polyol (Desmophen 1110
  BD, Bayer, Germany)
• A mixture of diphenylmethane-4,4-diisocyanate
  (MDI) with isomers and higher functional
  homologues (Desmodur VK 10, Bayer, Germany)

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EXPERIMENTAL

• Analysis methods
• Differential Scanning Calorimetry (DSC)
• Dynamic Mechanical Analysis (DMA)
• Lap shear strength ASTM D-1002
• Peel strength ASTM D-1876

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Glass Transition Temperature of PUR - POSS
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The effect of 1, 3 and 5 wt POSS-octaphenyl on
storage modulus
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The effect of 1, 3 and 5 wt POSS-glycidoxypropyl
on storage modulus
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Adhesive Properties Shear Strength
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Adhesive Properties Peel Strength
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CONCLUSIONS

• The type of the functional groups (reactive/non
  reactive) of the POSS nano particles, is the
  dominant factor in the formation of the molecular
  network and resultant properties
• Optimal concentration exists for each functional
  derivative of POSS for Tg increase of adhesives
  systems
• Optimal concentration exists for each functional
  derivative of POSS for toughening of adhesives
  systems
• Only small amounts (lt 5) are needed to cause
  significant improvements, due to the large
  surface area of nano particles
• Excess amounts results in plasticization effect

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Acknowledgements

• Tehila Efrat Shenkar, UML
• Irena Belinsky - IPRC
• THANK YOU
• FOR THE ATTENTION