PAMAM Dendrimers

Poly(amido amine) (PAMAM) dendrimers represent an exciting new class of macromolecular architecture called "dense star" polymers. Unlike classical polymers, dendrimers have a high degree of molecular uniformity, narrow molecular weight distribution, specific size and shape characteristics, and a highly- functionalized terminal surface. The manufacturing process is a series of repetitive steps starting with a central initiator core. Each subsequent growth step represents a new "generation" of polymer with a larger molecular diameter, twice the number of reactive surface sites, and approximately double the molecular weight of the preceding generation.

Generation 2 PAMAM Dendrimer
(Click for larger view)

The term "dendrimer" was derived from its tree-like branching structure. The table below shows the calculated properties* of amine surface functional PAMAM dendrimers by generation.

Generation

Molecular Weight

Measured Diameter (Å)

Surface Groups

0

517

15

4

1

1,430

22

8

2

3,256

29

16

3

6,909

36

32

4

14,215

45

64

5

28,826

54

128

6

58,048

67

256

7

116,493

81

512

8

233,383

 97

 1024

9

467,162

 114

 2048

10

934,720

 135

 4096


*Theoretical Properties, not to be used as specifications.

Generation

Molecular
Weight*

End Groups*

PAMAM Dendrimer Succinamic acid G2
4856
16
PAMAM Dendrimer Succinamic acid G3
10109
32
PAMAM Dendrimer Succinamic acid G4
20615
64
PAMAM Dendrimer Succinamic acid G5
41626
128
PAMAM Dendrimer Succinamic acid G6
83648
256

 

Below: The step-growth reaction of EDA to Generation 5 PAMAM Dendrimer