Dispersants 155
The methods to make DVMs are shown in Figures 5.13 through 5.15. These are synthesized by
Grafting or reacting of a dispersancy-imparting monomer on an already-formed polymer,
as in the case of EPRs and SDRs [76–84].
Including such a monomer during the polymerization process, as in the case of polyacry-
lates and PMAs [85].
Introducing a reactive functional group in the polymer that can be reacted with a reagent to
impart dispersancy, as in the case of styrene–maleic anhydride copolymers [40,86–93].
Although most of the examples in Figures 5.13 through 5.15 pertain to the introduction of the basic
nitrogen-containing moieties, neutral DVMs are also known in the literature. These are made by
using nonbasic reactants, such as N-vinylpyrrolidinone, alcohols, or polyether-derived methacry-
late ester [79,94,95]. Recently, dispersant viscosity–improving additives with built-in oxidation
Diamines
H 2 N
H 2 N
H 2 N
H 2 N
H 2 N
H 3 C
NH 2
NH 2
NH 2
NH 2
NH 2
Ethylenediamine
Triamines
Tetramines
Triethylenetetramine Aminoethylaminoethylpiperazine
N,N-dimethylaminopropylamine Primary amino group (1°)
Secondary amino group (2°)
Tertiary amino group (3°)
1 °
1 ° 1 °^3 °^2 °
2 °
2 °
3 °
2 ° 3 °
2 °
1 °
1 °
NH 2
1 °
1 °
3 °
CH 3
N
N N
H
N
NN
N
H
N
H
H
NH 2
NH
NH
N
Diethylenetriamine Aminoethylpiperazine
HN N
Bis(aminoethyl) piperazine
Alcohols
HO
HO
OH
OH
HO
HO
OH
Pentaerythritol
CH 3
HO
HO
OH
NH 2
Trimethylolpropane
Tris(hydroxymethyl)propane
Tris(hydroxymethyl)aminoethane
FIGURE 5.8 Amines and alcohols used to synthesize dispersants.