Driving Force for the Formation of Supramolecular Structures
Hydrophobic interaction
< 40 kJ/mol
Electrostatic interaction
- 20 kJ/mol
Hydrogen bond interaction
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Hydrophobic interaction
Hydrophobic molecules tend to be non-polar and thus prefer other neutral molecules and non-polar solvents.
Hydrophobic molecules in water often cluster together forming micelles. Water on hydrophobic surfaces will exhibit a high contact angle.
Non-covalent forces that hold supramolecular polymers together include coordination, π-π interactions, and hydrogen bonding.
O
胸腺嘧啶 CH3 O
O P OH O
H2C O
腺嘌呤 H N H
12~30 kJ/mol
Van der Waals interaction
0.4-4 kJ/mol
Cation-π interaction
5-80 kJ/mol
π-π interaction
0-50 kJ/mol
Coordination interaction (Host-guest interaction)
“Supramolecular Chemistry is the chemistry of the intermolecular bond, concerning
the structure and functions of the entities formed by the association of two or
N
N
HN N O
NN O
胞嘧啶 H
O P OH O
H2C O
H
鸟嘌呤 O
N
NH
N N NH
H
O
O CH2 O
HO P O O
CH2 O HO P O O
3
Supramolecular polymer
Colloid Early 20th century
Linear polymer from 1930
more chemical species.” (by Jean-Marie Lehn)
Covalent bond
C-O bond
340kJ / mol
C-C bond 360kJ / mol
C-H d
430kJ / mol
C=C bond600kJ / mol
C=O bond
690kJ / mol
Supramolecular polymer from 1997
Jean-Marie Lehn
Donald J. Cram Charles J. Pedersen
4
Definition of Supramolecular polymer
Polymeric arrays of monomeric units that are brought together by reversible and highly directional secondary interactions, resulting in polymeric properties in dilute and concentrated solutions, as well as in the bulk.
the attractive forces that hold geckos to surfaces are van der Waals interactions between the finely divided setae and the surfaces themselves.
Every square millimeter of a gecko's footpad contains about 14,000 hair-like setae. Each seta has a diameter of 5 micrometers.
molecular chemistry atom + atom → molecular（covalent）
supramolecular chemistry molecular + molecular → supramolecular
（noncovalent）
5
Intermolecular Interactions
6
van der Waals Interaction: Sticky Secrets of the Gecko
The toes of the gecko have a special adaptation that allows them to adhere to most surfaces without the use of liquids or surface tension.
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Hydrogen bond
A hydrogen bond is the attractive interaction of a hydrogen atom with an electronegative atom, like nitrogen, oxygen or fluorine.
Introduction to polymer science
Supramolecular polymers
超分子聚合物
1
Basic of the Supramolecular
2
Supramolecular polymer
A supramolecular polymer is a polymer whose monomer repeat units are held together by noncovalent bonds.