Electrostatic Complexes in Polymer Materials Science Feng Li, Phillip Schorr, Akira Ishikubo, Jean-François Argillier, Marc Balastre, Ryan Toomey, Rob Farina, Ray Tu & Matthew Tirrell, with Phil Pincus (UCSB), Jimmy Mays (U Tenn), and Matthias Ballauff (Bayreuth) Chemical Engineering, Materials and BioMolecular Science & Engineering Materials Research Laboratory California NanoSystems Institute Institute for Collaborative Biotechnologies University of California, Santa Barbara [email protected]www.chemengr.ucsb.edu/people/faculty/ tirrell Polymers as Nanomaterials National TsingHua University January 17, 2008
1. Electrostatic Complexes in Polymer Materials Science Feng
Li, Phillip Schorr, Akira Ishikubo, Jean-Franois Argillier, Marc
Balastre, Ryan Toomey, Rob Farina, Ray Tu & Matthew Tirrell,
with Phil Pincus (UCSB), Jimmy Mays (U Tenn), and Matthias Ballauff
(Bayreuth) Chemical Engineering, Materials and BioMolecular Science
& Engineering Materials Research Laboratory California
NanoSystems Institute Institute for Collaborative Biotechnologies
University of California, Santa Barbara [email_address]
www.chemengr.ucsb.edu/people/faculty/ tirrell Polymers as
Nanomaterials National TsingHua University January 17, 2008
2. Stacking Coordination via multi-valent metals Hydrogen
bonding Useful non-covalent interactions for building
supermolecular structures Assemblies result from multipicity of
weak individual interactions
3. poly(styrene sulf Decher, Science Layer-by-Layer Assembly M
olecular B eaker E pitaxy
4. 2001
5. ENCAPSULATION PROCESS BY COMPLEX COACERVATION USING
INORGANIC POLYMERS NCR Co. (1970) Document Type and Number: United
States Patent 3639256 "Complex coacervation" a process wherein at
least two oppositely electrically charged hydrophilic polymeric
materials are caused to emerge from aqueous solution by being
mutually attracted to and complexed with one another and by,
thereby, having their solubility in the aqueous manufacturing
vehicle decreased. In the instance of complex coacervation, the
emergent phase contains substantially all of the electrically
charged hydrophilic polymeric material utilized in forming the
complex . Possibilities for supermolecular assembly (Cohen-Stuart,
et al
6. Experimental System Charge density >85% N >> M SO 3
- Na + CH 2 [ CH M CH 2 CH [ ] N C 4 H 9 ] Parameters that affect
the structure and interaction of polyelectrolyte brushes:
adsorption density ( ) a dded salt concentration (Cs) charge
density ( ) number of charged segments (N) Large Well-Solvated
Block (Hydrophilic) Small Collapsed Block (Hydrophobic) adsorbed
onto Hydrophobic surface (Octadecyltriethoxysilane (OTS) onto mica)
High affinity with the anchor block
7. Beaglehole Picometer
8. Adsorption Mechanisms of Charged, Amphiphilic Diblock
Copolymers: The Role of Micellization and Surface Affinity, R.
Toomey and M. Tirrell, Macromolecules , 38 , 5137-5143 (2005).
Post-Adsorption Rearrangements of Block Copolymer Micelles at the
Solid/Liquid Interface, R. Toomey and M. Tirrell, Macromolecules,
39 , 2262-2267 (2006).
9. Experimental System Charge density >85% N >> M SO 3
- Na + CH 2 [ CH M CH 2 CH [ ] N C 4 H 9 ] Parameters that affect
the structure and interaction of polyelectrolyte brushes:
adsorption density ( ) a dded salt concentration (Cs) charge
density ( ) number of charged segments (N) Large Well-Solvated
Block (Hydrophilic) Small Collapsed Block (Hydrophobic) adsorbed
onto Hydrophobic surface (Octadecyltriethoxysilane (OTS) onto mica)
High affinity with the anchor block
10. SFA ( surface force apparatus) SFA Mark II Israelachvili,
J. N. Intermolecular and Surface Forces ; Academic Press: San
Diego, 1992 Distance ( ) F/R Derjaguin approximation: D=2L 0
11. Force Profile Of PtBS 15 /NaPSS 612 (MT 6 ) in Water with
Added Salt
12. Force Profile Of PtBS 15 /NaPSS 438 (MT 5 ) in Water with
Added Salt
13. Force Profile Of PtBS 27 /NaPSS 747 (MT3) in Water with
Added Salt
14. Mono-valent salt concentration dependence of brush height
Force curve depending on [NaNO 3 ] [ NaNO 3 ] vs. maximum brush
length Osmotic brush regime Salted brush regime Elastic force
Osmotic pressure L 0 = brush height L = equilibrium brush height, N
= number of monomer units of Kuhn length a, = adsorption density,
kT = thermal energy, = ratio of the total number of free mobile
counter ions to the total number of monomer segments Pincus, 1991
0.3M 0.12M 0.056M 0.02M 5.6mM 0.92mM 0.11mM Osmotic brush regime
salted brush regime
15. Molecular Information and Adsorption Density of PtBS-NaPSS
Diblock Copolymers 9.20.3 12.5 0.5 7.40.2 Adsorption Density , (10
15 chains/m 2 ) 1.04 1.03 1.04 Polydispersity 84% 85% 87% Degree of
Sulfonation , 632 438 747 Chain Length of NaPPS Block, N 15 15 27
Chain Length of PtBS Block MT6 MT5 MT3 Polymer Name
16. Salt Concentration Dependence of the Brush Height Salt
concentration dependence of the brush height for the three
different brushes. The solid and dash ed lines are linear fits. The
dashed lines have slopes close to zero. The slopes for the linear
fit 1, 2, and 3 are -0.33 0.02, -0.33 0.02, and -0.30 0.02,
respectively.
17. Molecular Weight Dependence of the Brush Height at the
Lowest Salt Concentration Molecular weight dependence of the brush
height for the four different brushes in the osmotic regime (the
lowest salt concentration). is the ratio of the total number of
free mobile counterions to the total number of monomer segments
.
18. Debye Screening Length and Counterion Condensation Debye
screening length -1 = (8 l B c 0 ) -1/2 Gouy-Chapman length = (2 l
B c 0 L 0 ) where l B is the Bjerrum length L >> , indicating
that the counterions are located inside the brush. The extent of
counterion condensation is greater than predicted by Manning
theory. 58% 59% 60% Fraction of Counterion Condensation (Manning
Theory) 82 5% 84 5% 81 5% Fraction of Counterion Condensation
(Experimental) 0.071 0.002 0.091 0.002 0.059 0.002 Concentration of
Total Counterions Inside the Brush (M) 0.013 0.002 0.015 0.002
0.011 0.002 Concentration of Free Counterions Inside the Brush (M)
75 5% 79 5% 71 5% Maximum Height of the Brush (in % of the Contour
Length) 3 3 2 Gouy-Chapman Length at c 0 ( ) 27 2 25 2 29 2 Debye
Screening Length at c 0 () 0.013 0.002 0.015 0.002 0.011 0.002
Crossover Concentration, c 0 (M) MT6 MT5 MT3 Polymer Name
19.
20.
21.
22.
23. Effect of Salt Concentration
24. Effect of Salt Concentration
25. Effect of Salt Concentration
26.
27.
28.
29. Al
30.
31.
32.
Preparation of polymer brush on hydrophobically modified
mica
in SFA camber. (100ppm polymer, 0.4M NaNO 3 )
Replace to 1 mM NaNO 3 solution.
CTAB addition into SFA chamber and force-distance
measurement.
(CTAB concentration : from 10 -3 mM to 100 mM)
CTAB dilution and force-distance measurement.
(CTAB concentration : from 100 mM to 10 -3 mM)
Polyelectrolyte brush Oppositely charged surfactant Experimental
procedure for surfactant experiments
33. CTAB addition CTAB : cethyltrimethylammonium bromide
Condition : [NaNO3] = 1mM, 30 Open : compression Closed :
separation CTAB concentration 0 mM 0.002 mM 0.02 mM 0.4 mM
34. CTAB addition CTAB 0.4mM CTAB 2.9mM CTAB 74mM - + + + + + -
- - - - - - - - - - - - Polymer from left surface Polymer from
right surface +
35. log(CTAB[M]) or log(NaNO 3 [M]) log(L 0 ) NaNO 3 addition ,
CTAB addition cmc CTAB concentration dependence of brush height L 0
Attractive force Original brush height
36. Al CTAB Na
37. CTAB dilution process CTAB 74mM CTAB 6.4mM CTAB 0.47mM CTAB
0.06mM CTAB 0.01mM L1 L2 * Compressed polymer height decreased *
Attractive force increased up to a point
38. Addition of high salt concentration solution NaNO 3 1mM
CTAB 0.01mM NaNO 3 0.7M NaNO 3 1.2mM Distance () F/R( N/m) Distance
() Distance ()
39. Summary CTAB addition process 0 mM Strong attraction after
contact CTAB dilution process
Polymer brush shrinks
Attractive force increased
CTAB remains in the
polymer layer
Original structure isnt recovered. Brush starts to shrink from 10
-6 M Multi-charged complex formation 10 -5 10 -4 M CMC = 10 -3 M
CAC in dilute solution = 10 -4 M
40. Manipulation of Surface Interactions NSF-MRSEC (UCSB-MRL)
NSF-NIRT (CTS-0103516) NSF-MWN (DMR-0713827) NIH (HL-R0162427-01,
PEN, CCNE) ARO Inst. For Collaborative Biotech. Thank you! Badri
Ananthanarayanan Matthew Black Rob Farina Mark Kastantin Brian Lin
Rachel Marullo Amanda Trent Hongbo Zeng Former group members
(contributing to this work) Akira Ishikubo (Shiseido) Phillip
Schorr (Kimberly-Clark) Feng Li (cole Normale, Paris) Jean-Franois
Argillier (IFP) Marc Balastre (Rhodia) Ryan Toomey (Univ. of South
Florida) STUDENTS: Alejandro Parra Thorsten Neumann Wirasak
Smitthapong Dimitris Missirlis Rungsima Chollakup POSTDOCS and
VISITORS: