Online Resource
2,5-Di-(2-ethylhexanoylperoxy)-2,5-dimethylhexane as difunctional radical initiator in
reverse iodine transfer polymerization (RITP) of styrene, methyl methacrylate and butyl
acrylate
JOURNAL OF POLYMER RESEARCH
Francisco J. Enríquez-Medrano 1,2, Alejandro M. Villa-Hernández 1, Hortensia MaldonadoTextle 2, Ramiro Guerrero-Santos 2 and Patrick Lacroix-Desmazes 1*
1
Institut Charles Gerhardt (ICG), UMR 5253, CNRS, Université Montpellier, ENSCM.
Ingénierie et Architectures Macromoléculaires (IAM), Ecole Nationale Supérieure de Chimie
de Montpellier, 8 rue de l’Ecole Normale, 34296 Montpellier, France.
2
Centro de Investigación en Química Aplicada, Departamento de Síntesis de Polímeros, Blvd.
Enrique Reyna, No. 140, 25294, Saltillo, México.
* patrick.lacroix-desmazes@enscm.fr
1
Codes for the formation of P-I chains by reaction of fragment Z from the initiator with
molecular iodine I2 in the presence of monomer (Z-Mn-I):
Difunctional initiator: Trigonox 141 : general structure X-Z-X
Fragments of decomposition : X + Z + X
Formation of P-I from X
Y=Yes
N=No
Total
probability
α
1-α
1
Formation of P’-I from Z
Y=Yes
N=No
Total
probability

1-
1
Probability of events from Z biradical fragment:
Radical 1
Radical 2
Case 1
N
1-
N
1-
Case 2
Y

N
1-
Case 3
N
1-
Y

Case 4
Y

Y

Total
Polymer chains are formed only in cases 2, 3, 4
Total probability for cases 2, 3, 4 = 2(1-) + ²=2-²
chains
nothing
I-P’
P’-I
I-P’-I
probability
probability (1-)²
probability (1-)
probability (1-)
probability ²
1
Probability of events in the case of a symmetrical initiator X-X (e.g. initiator LYP):
P-I
I-P
α
α
2α chains corresponding to 1 molecule of molecular iodine I2 initially involved
Mn,theoretical,α =
(mmonomer,0 )(𝜌)
(2α)(nI2 ,0 )
Probability of events in the case of a symmetrical initiator Z-Z (e.g. initiator P16S):
P’-I
I-P’


2 chains corresponding to 1 molecule of molecular iodine I2 initially involved
Mn,theoretical,β =
(mmonomer,0 )(𝜌)
(2β)(nI2,0 )
Probability of events in the case of an asymmetrical initiator X-Z (e.g. initiator T121):
P-I
I-P’
α

α+ chains corresponding to 1 molecule of molecular iodine I2 initially involved
Mn,theoretical,∝,β =
(mmonomer,0 )(𝜌)
(α + β)(nI2 ,0 )
2
Probability of events in the case of a difunctional initiator X-Z-X (e.g. initiator T141):
P-I
I-P’, P’-I, I-P’-I
I-P
α
2-²
α
Total probability = 2+ 2 - ²
2α + 2 - ² chains corresponding to 2 molecules of molecular iodine I2 initially involved
(2α + 2 - ²)/2 chains corresponding to 1 molecule of molecular iodine I2
So,
Mn,theoretical,∝,β =
(mmonomer,0 )(𝜌)
2α + 2β − β2
(
) (nI2 ,0 )
2
Which can be written:
Mn,theoretical,∝,β =
(mmonomer,0 )(𝜌)
2α + β´
(
) (nI2,0 )
2
where β´ = 2β − β2
3
Figure S1: Decomposition of the radical initiator T141, including the possible
decarboxylation and beta-scission reactions. The two main radical species expected to be
formed under the experimental conditions used in this work are framed.
4
Figure S2: Decomposition of the radical initiator LYP, including the possible decarboxylation
reaction. The main radical expected to be formed under the experimental conditions used in
this work is framed.
5
Figure S3: Decomposition of the radical initiator P16S, including the decarboxylation
reaction. The main radical expected to be formed under the experimental conditions used in
this work is framed.
6
Figure S4: Decomposition of the radical initiator T121, including the possible
decarboxylation and beta-scission reactions. The two main radicals expected to be formed
under the experimental conditions used in this work are framed.
7