Amplifying (Im)perfection: The Impact of Crystallinity in Discrete and Disperse Block Co-oligomers

Article abstract of DOI:10.1021/jacs.7b08627

Crystallinity is seldomly utilized as part of the microphase segregation process in ultralow-molecular-weight block copolymers. Here, we show the preparation of two types of discrete, semicrystalline block co-oligomers, comprising an amorphous oligodimethylsiloxane block and a crystalline oligo-l-lactic acid or oligomethylene block. The self-assembly of these discrete materials results in lamellar structures with unforeseen uniformity in the domain spacing. A systematic introduction of dispersity reveals the extreme sensitivity of the microphase segregation process toward chain length dispersity in the crystalline block.

Full text of DOI:10.1021/jacs.7b08627

Subscriber access provided by UNIV OF CAMBRIDGE
Communication
Amplifying (im)perfection: The Impact of Crystallinity
in Discrete and Disperse Block Co-oligomers
Bas Van Genabeek, Brigitte Lamers, Bas F.M. de Waal, Martin Van Son, Anja R.A. Palmans, and E. W. Meijer
J. Am. Chem. Soc., Just Accepted Manuscript • DOI: 10.1021/jacs.7b08627 • Publication Date (Web): 10 Oct 2017
Downloaded from http://pubs.acs.org on October 10, 2017
Just Accepted
“Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted
online prior to technical editing, formatting for publication and author proofing. The American Chemical
Society provides “Just Accepted” as a free service to the research community to expedite the
dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts
appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been
fully peer reviewed, but should not be considered the official version of record. They are accessible to all
readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered
to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published
in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just
Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor
changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers
and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors
or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
Journal of the American Chemical Society is published by the American Chemical
Society. 1155 Sixteenth Street N.W., Washington, DC 20036
Published by American Chemical Society. Copyright © American Chemical Society.
However, no copyright claim is made to original U.S. Government works, or works
produced by employees of any Commonwealth realm Crown government in the course
of their duties.

Page 1 of 8
Journal of the American Chemical Society
1
2
3
4
5
6
Amplifying (im)perfection: The Impact of Crystallinity in Dis-
crete and Disperse Block Co-oligomers
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
Bas van Genabeek, Brigitte A. G. Lamers, Bas F. M. de Waal, Martin H. C. van Son, Anja R. A.
Palmans and E. W. Meijer*
Institute for Complex Molecular Systems and Laboratory of Macromolecular and Organic Chemistry, Eindhoven
University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
Supporting Information Placeholder
9
crystalline materials. Also the use of one or two
ABSTRACT: Crystallinity is seldomly utilized as part of the
(
semi)crystalline blocks in (diblock) BCPs has received a
microphase segregation process in ultra-low MW block co-
polymers. Here, we show the preparation of two types of
discrete, semicrystalline block co-oligomers, comprising an
amorphous oligodimethylsiloxane block and a crystalline
10–12
great deal of attention.
Furthermore, numerous examples
highlight the importance of molecular perfection (i.e., se-
quence control) in other classes of self-assembling oligomer-
13,14
ic sequences.
oligo-L-lactic acid or oligomethylene block. The self-
assembly of these discrete materials results in lamellar struc-
tures with unforeseen uniformity in the domain spacing. A
systematic introduction of dispersity reveals the extreme
sensitivity of the microphase segregation process toward
chain length dispersity in the crystalline block.
In the context of a ‘simple’ diblock copolymer design, un-
derstanding and exploiting the optimal blend of (directional)
molecular interactions and full synthetic control still is in its
infancy. Even though the development of ‘high χ-low N’ BCPs
has led to ever smaller domain spacings, the general trend is
to evade the use of crystalline blocks, and the extent of long-
6,8,15–18
range order in the resulting systems is often limited.
A
notable exception here is the work of Booth and coworkers
1
9–21
Self-organization in (di)block copolymers (BCPs) has
proven itself, both theoretically and experimentally, as a
robust and well-established strategy to generate organized
structures at nano- and mesoscopic length scales reaching
on poly(ethylene oxide-b-propylene oxide),
poly(ethylene
and poly(ethylene oxide-b-
in di- and triblock configurations.
22–24
oxide-b-butylene oxide)
methylene)
25–29
1
–3
We prepared two types of discrete BCOs that consist of
amorphous oDMS linked to a crystalline block. The first is
related to oDMS-oLA and a second contains oDMS covalent-
ly bound to an alkane of intermediate length (Figure 1A and
beyond that of small, organic molecules. Yet, the gap be-
tween small, perfectly defined molecules and traditional
4,5
polymers is slowly fading. In earlier work, we illustrated
our efforts to amalgamate full synthetic control and BCP self-
6
B). As shown before, discrete, isotactic oligo-
L-lactic acid
assembly. Low MW block co-oligomers (BCOs) composed of
30
(
oLLA) is crystalline, forming well-defined lamellea. Like-
discrete oligodimethylsiloxane (oDMS) and discrete, atactic
oligolactic acid (oLA) exhibited self-assembly behavior that is
qualitatively analogous to that of traditional, disperse block
copolymers, but allowed the exploration of a far lower mo-
wise, poly- and oligomethylene are semicrystalline materials,
31
also organizing into lamellar domains. The oDMS-oLLA
BCO studied in this work consists of 15 siloxane and 17 L-
7
lactic acid repeat units, abbreviated as [Si15-LLA17]. This BCO
design permits a systematic study of discrete and (partially)
disperse semicrystalline oDMS-oLLA and a direct compari-
son with our previous study on the fully amorphous sister
lecular weight regime. In line with this work, Hawker and
8
coworkers simultaneously reported similar observations.
To evolve nano- and mesoscale organization of BCOs into
a higher level of perfection, the introduction of additional
interactions that further guide self-assembly and increase the
effective interaction parameter χ of the incompatible blocks
is required. Such interactions can be diverse in nature—Van
der Waals, dipole, π–π, and others—and have already been
exploited in, for example, the molecular designs of liquid
7
compounds (vide infra). Additionally, an oligodimethylsilox-
ane-oligomethylene (oDMS-oM) BCO was chosen, compris-
ing 7 siloxane repeat units to a C33 alkane (i.e., [Si -M ]).
7
33
Similar to [Si -LLA ], the volume fraction of the crystalline
15
17
block
is
close
to
0.50.
ACS Paragon Plus Environment

Journal of the American Chemical Society
Page 2 of 8
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
Figure 1. Molecular structures of [Si -LLA ] (A) and [Si -M ] (B). (C) DSC traces of [Si -LLA ] (black) and [Si -M ] (red). The
data is shifted vertically for clarity. The order-disorder transition unrelated to the crystallization process is indicated with an
15
17
7
33
15
17
7
33
asterisk. (D) Room temperature SAXS data for discrete [Si -LLA ] (top) and [Si -C ] (bottom). The data is shifted vertically for
15
17
7
33
clarity. A selection of higher order reflections is indicated.
Table 1: Molecular and morphologic characterization data.
a
b
#Si
c
d
N
e
fcr
*
Entry Compound
#M or Mn,calcd Mn,SEC
Ð
Tm
ΔHfus
TODT
d
b
-1 f
#
LLA [Da]
[Da]
2114
[°C]
43.8
[kJ mol ]
[°C] [nm]
h
h
1
[Si -M ]
7
33
17
982
<1.00001
<1.00001
1.04
15.6 0.51
71
n.o.
79.1
5.77
11.7
7
33
2
3
4
5
[Si -LLA ]
15
2486
2587
2356
2470
4380
4444
4482
4463
32.0 0.47 85.1
33.0 0.45 87.9
78
80
15
17
g
[Si~15-LLA17]
15.8 17
83.5 12.4
g
g
i
[Si -LLA~17]
15
15
15.2
1.13
30.5 0.44 87–125 42
n.o.
n.o.
12.7
18.3
15
g
i
[Si~15-LLA~17
]
16.2
1.13
31.3
0.45 90–129 25
[
a] Disperse blocks are indicated with a tilde (~) character preceding the (desired) average block lengths. [b] Number of silox-
ane, methylene or -lactic acid repeat units. [c] Calculation based on the total number of repeat units. [d] Number of segments
based on a 110 Å reference volume. [e] Volume fraction of the crystalline block, calculated using bulk densities for PDMS (0.95 g
L
3
-1 6,7
-1 32
-1
mL ), PLLA (1.29 g mL ) and tritriacontane (0.82 g mL ). [f] Heat effect per mole of BCO. [g] Average value. [h] Calculated
from relative peak intensities in the MALDI-TOF spectra. [i] A broad melting range was observed. n.o.: not observed.
oDMS-oLLA was synthesized according to the same proto-
col employed for the synthesis of atactic oDMS-oLA, with the
sole difference that optically pure L-lactide was used as the
For both BCOs, we attribute the endothermic transitions
at the highest temperatures to melting transitions of the
crystalline blocks and the formation of an isotropic state.
This was corroborated with polarized optical microscopy
(Figure S6) and small angle X-ray scattering (SAXS, Figure
S7) experiments at temperatures above and below these
transitions. Possibly, the observed reduction in Tm of the
BCO [Si -M ] is caused by alkyl chain folding, which is (par-
starting material instead of the racemic DL-lactide (see Sup-
porting Information, Schemes S1-S3). The synthetic strategy
toward discrete [Si -M ] (Scheme S4) employed the efficient
7
33
33
and selective Karstedt hydrosilylation as a key reaction step.
This enabled the use of synthetically accessible oDMS hy-
7
7
33
dride and a C33 α-olefin. The high purity of both BCOs and
absence of oligomers with a different number of repeat units
was confirmed with NMR and mass spectroscopy
(MALDI-TOF) (Figures S1–5).
tially) supported by X-ray scattering measurements (vide
infra). Apparently, chain folding is not occurring in BCO
[Si -LLA ]. The remaining transition in the cooling trace of
15
17
[Si -LLA ] is attributed to an order-disorder transition,
15
17
which is also present in most of the atactic oDMS-oLA BCOs
previously published. In contrast, we ascribe the second
The thermal signatures of [Si -LLA ] and [Si -M ] were
captured with differential scanning calorimetry (DSC; Figure
C and Table 1, entries 1–2). Each compound revealed strong
15
17
7
33
6
transition in BCO [Si -M ] to a solid-solid phase transition
1
7
33
3
4–37
involving a reorganization of the alkyl chains.
and narrow endothermic transitions. The transition of
[Si -LLA ] started close to the known melting point of pure
oligo-L-lactic acid LLA16 (Tm = 90 °C, ΔHfus = 71 kJ mol ) and
The formation of an ordered crystalline state was further
investigated with SAXS at room temperature in medium-
(MAXS) and wide-angle (WAXS) operating modes (see Fig-
ure 1D). Remarkably, both discrete BCOs reveal an unprece-
dentedly high number of equally spaced reflection peaks
(q/q* up to √121 for [Si -LLA ]), indicative for a high degree
15
17
-
1
showed a similar transition enthalpy. As a result of the 7 °C
hysteresis upon cooling, a new, low-intensity exotherm ap-
peared at 79 °C, preceding the primary peak (indicated in
Figure 1C with an asterisk). BCO [Si -M ] shows two transi-
7
33
15
17
tions; at 36 °C and at 44 °C. Interestingly, no further transi-
tions were observed at higher temperatures, although pure
of long range order. The distance between the reflections
unambiguously points to the presence of a lamellar structure
with a lamellar domain spacing dlam = 2π/q* = 11.7 nm for
[Si -LLA ] and d = 5.8 nm for [Si -M ]. The latter is one
of the smallest feature sizes hitherto observed. At higher q-
values, additional scattering peaks reveal further interchain
3
4
tritriacontane (C H ) has a melting point at 72 °C. The
3
3
68
enthalpy associated with the transition at 44 °C (71 kJ (mol
15
17
lam
7
33
-1
15
BCO) ) has a similar value as the enthalpy of fusion of tritri-
-1 34
acontane (79.5 kJ mol ).
ACS Paragon Plus Environment

Page 3 of 8
Journal of the American Chemical Society
organization. For BCO [Si -LLA ], a broad reflection at q =
relatively low. Mass spectrometry nicely captures the striking
differences between ‘no’ and ‘low’ dispersity (Figure S9).
15
17
-
1
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
8.6 nm is attributed to the amorphous siloxane block. The
sharp reflections at larger q originate from the crystalline
oLLA block, which is in concordance with the scattering
The thermal behavior of [Si~15-LLA ] is very similar to that
17
of its discrete analogue, albeit with a slightly higher Tm of the
oLLA block. Currently, we do not have an explanation for
this observation. The upward shift of TODT with increasing
dispersity (see the transitions marked with an asterisk in
Figure S10) is similar to the trend observed in the atactic
profile of the pure LLA (Figure S7A) and known profiles for
16
38
PLLA. Interestingly, BCO [Si -M ] gave a significantly more
7
33
-1
narrow siloxane reflection around q = 8.7 nm , along with a
-
1
-1
sharp peak at 14.9 nm , a shoulder at q = 16.7 nm , and a
-
1
7
weak reflection at 24.9 nm . The last three reflections sug-
gest that the alkyl blocks crystallize in the same orthorhom-
bic substructure as linear alkanes.
BCOs. Interestingly, we find significant changes in the
thermal behavior if a disperse oLLA block is incorporated.
Instead of a sharp melting transition, melting occurs over a
broad temperature range. Moreover, ΔHfus decreases by 45–
3
9,40
In addition, sharpen-
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
ing of the siloxane reflection band is an indication that the
variability of interchain distances within the oDMS block is
smaller in [Si -M ] compared to that in [Si -LLA ]. Presum-
70%, albeit that the determination of ΔHfus became less accu-
7
33
15
17
rate as a result of the peak broadening.
ably, this is the result of the combined effect of crystallinity
in the oM block and the short stretched-chain length of the
oDMS block in BCO [Si -M ].
7
33
The nearly symmetric composition of the BCOs dictates
that the thicknesses of the amorphous and crystalline blocks
both should be around half dlam. For BCO [Si -LLA ] (d =
lam
15
17
11.7 nm)—taking into account the domain spacing of pure
LLA16 (dlam = 5.2 nm, see Figure S7A)—we propose that the
lamellar structure is composed of interdigitated, fully
stretched oLLA chains, aligned perpendicularly to the do-
main boundary. Additionally, the short molecular length of
the Si15 block causes the amorphous part to consist of an
elongated oDMS coil, as depicted in Figure S8A. In case of
BCO [Si -M ], we envision a similar structure. However, the
7
33
estimated extended chain length in the crystalline C33 alkyl
3
4
block (~4.4 nm, see Figure S7B and literature values) is
50% larger than half of the domain spacing of the BCO. As a
consequence, the oM long-axis might be tilted relative to the
1
27
28
normal of the interdomain planes or folded once (Figures
S8B and C, respectively). The proposed chain orientation of
the oLLA and oM blocks is in correspondence with the melt-
ing transitions of the BCOs compared to those of the crystal-
line homoblocks.
Figure 2. Room temperature SAXS data for discrete and
(
partially) disperse oDMS-oLLA BCOs. The data is shifted
vertically for clarity. A selection of higher order reflections
The large number of observed reflection peaks is uncom-
are indicated as q/q* values or with black triangles. FWHM =
27,41,42
-1
mon for BCPs, particularly in such low MW materials.
full width at half maximum. The broad peak at q = 4 nm
43
According to paracrystalline theory, the high number of
results from background scattering (Kapton tape).
observed reflections permits only a small variability in the
lamellar thickness throughout the microphase segregated
sample. Although crystallinity undoubtedly enhances the
uniformity of the lamellar domains, we wondered to what
extent the discrete nature of the materials plays a role in
obtaining such highly organized structures. We therefore
synthesized three additional BCOs: [Si~15-LLA ], [Si -LLA~17]
The phase behavior of the disperse polymers at room tem-
perature was studied with SAXS (Figure 2). Discrete
[
Si -LLA ] and the BCO with a disperse Si block [Si~15-LLA17]
15 17
reveal a very similar scattering pattern, both indicative for a
highly ordered lamellar structure. Introduction of a disperse
oDMS block causes a 6% increase of the domain spacing (dlam
17
15
=
12.4 nm). This is accompanied by a broadening of the prin-
and [Si~15-LLA~17], incorporating a disperse oDMS, a disperse
oLLA or two disperse blocks, respectively. This allows a sys-
tematic screening of the effect of a discrete versus a disperse
block on the crystallization of the oLLA block and subse-
quent microphase separation. In the abbreviations, disperse
blocks are indicated with a tilde (~) character preceding the
cipal scattering peak, indicated by a 35% increase of the full
width at half maximum value (see Figure 2). Remarkably,
the degree of ordering decreases dramatically in the two
BCOs comprising a disperse oLLA block. Here, the principal
scattering peak at low q-values becomes very broad and only
a single, very weak second reflection is visible (indicated with
the black triangles in Figure 2). In contrast, all scattering
patterns look similar at large scattering angles. This is sug-
gestive for a very similar orthorhombic sub-unit cell in the
crystalline oLLA domain of all four BCOs, albeit that the DSC
data show that a fraction of the disperse oLLA blocks resides
in an amorphous state.
(
desired) average block lengths. The synthesis of the materi-
als is documented in the Supporting Information. As summa-
rized in Table 1, entries 3–5, oDMS and oLLA block lengths
and M values of the (partially) disperse materials were close
n
to those of the discrete analogues. Values for the molar mass
dispersity increased after introduction of one or two disperse
blocks, although the maximum value of Ð = 1.13 (for both
We propose that the crystalline nature of the oLLA pre-
cisely aligns the chains in a parallel manner, unaffected by
dispersity in the block. In case of the BCOs with discrete
[
Si -LLA~17] and [Si~15-LLA~17]) still can be considered as
15
ACS Paragon Plus Environment

Journal of the American Chemical Society
Page 4 of 8
oLLA chains, this results in near-perfect localization of the
chain ends and interblock connections in three-dimensional
space, greatly reducing any variations and fluctuations in
domain spacing that generally exist in completely amor-
phous systems. On the contrary, dispersity in the crystalline
block (primarily) forces the ordering of the block links along
the domain boundary out of alignment. This results in an
increased variation of the lamellar thickness, at the cost of
Delaney, K. T.; Connal, L. A.; McGrath, A. J.; Clark, P. G.;
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
Bates, C. M.; Hawker, C. J. ACS Macro Lett. 2017, 6, 668.
Handbook of Liquid Crystals; Goodby, J. W.; Tschierske, C.;
Raynes, P.; Gleeson, H.; Kato, T.; Collings, P. J., Eds.; Wiley-
VCH Verlag GmbH & Co. KGaA: Weinheim, Germany, 2014.
He, W.-N.; Xu, J.-T. Prog. Polym. Sci. 2012, 37, 1350.
Nandan, B.; Hsu, J.-Y.; Chen, H.-L. J. Macromol. Sci. Part C
Polym. Rev. 2006, 46, 143.
(
9)
(
(
10)
11)
(12)
Hamley, I. W. In Interfaces Crystallization Viscoelasticity;
Springer Berlin Heidelberg: Berlin, Heidelberg, 1999; pp.
(
long range) order. Likely, this effect is amplified by the
1
13–137.
absence of chain folds in this low MW system that can act as
a buffer for variations in chain length during the crystalliza-
tion process.
(
(
13)
14)
Sun, J.; Zuckermann, R. N. ACS Nano 2013, 7, 4715.
Badi, N.; Chan-Seng, D.; Lutz, J.-F. Macromol. Chem. Phys.
2013, 214, 135.
Jeong, G.; Yu, D. M.; Mapas, J. K. D.; Sun, Z.; Rzayev, J.;
Russell, T. P. Macromolecules 2017, acs. macromol.7b01443.
Kwak, J.; Mishra, A. K.; Lee, J.; Lee, K. S.; Choi, C.; Maiti, S.;
Kim, M.; Kim, J. K. Macromolecules 2017, acs.
macromol.7b00945.
Nowak, S. R.; Hwang, W.; Sita, L. R. J. Am. Chem. Soc. 2017,
jacs. 6b13285.
Carter, M. C. D.; Jennings, J.; Speetjens, F. W.; Lynn, D. M.;
Mahanthappa, M. K. Macromolecules 2016, 49, 6268.
Booth, C.; Pickles, C. J. J. Polym. Sci. Part A-2 Polym. Phys.
1973, 11, 249.
Viras, F.; Luo, Y.-Z.; Viras, K.; Mobbs, R. H.; King, T. A.;
Booth, C. Die Makromol. Chemie 1988, 189, 459.
Šimek, L.; Petřík, S.; Hadobaš, F.; Bohdanecký, M. Eur.
Polym. J. 1990, 26, 371.
Yang, Y.-W.; Tanodekaew, S.; Mai, S.-M.; Booth, C.; Ryan,
A. J.; Bras, W.; Viras, K. Macromolecules 1995, 28, 6029.
Mai, S.-M.; Fairclough, J. P. A.; Viras, K.; Gorry, P. A.;
Hamley, I. W.; Ryan, A. J.; Booth, C. Macromolecules 1997,
30, 8392.
Ryan, A. J.; Fairclough, J. P. A.; Hamley, I. W.; Mai, S.-M.;
Booth, C. Macromolecules 1997, 30, 1723.
Cooper, D. R.; Leung, Y.-K.; Heatley, F.; Booth, C. Polymer
1978, 19, 309.
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
In summary, we studied the self-assembly behavior of
oDMS-oLLA and oDMS-oM, incorporating additional crystal-
line interactions in the oligolactic acid and oligomethylene
blocks. Our results show that the introduction of crystallinity
indeed improves the self-assembly in BCOs, provided that
the crystalline block is discrete. This leads to exceptionally
uniform microphase segregated domains, and new avenues
to further decrease feature sizes. However, dispersity plays a
crucial role in the formation of ordered structures, causing in
a nearly complete loss of ordering if the crystalline block has
a non-uniform length. Although this is easily explained with
a simple, intuition-based molecular picture, no comparative
experimental studies existed to date. Currently, we further
elucidate the exact molecular organization in semicrystalline
BCOs, and their intriguing temperature dependent behavior,
by using other block(length) combinations and architectures.
(15)
16)
(
(17)
18)
(
(19)
(20)
(
(
21)
22)
(23)
ASSOCIATED CONTENT
Supporting Information
(
24)
The Supporting Information (PDF file) is available free of
charge on the ACS Publications website. Supporting Infor-
mation includes: Experimental procedures, characterization
data for all compounds and Figures S1-S10.
(25)
(26)
Domszy, R. .; Mobbs, R. .; Leung, Y.-K.; Heatley, F.; Booth,
C. Polymer 1979, 20, 1204.
(
(
27)
28)
Swales, T. G. E.; Domszy, R. C.; Beddoes, R. L.; Price, C.;
Booth, C. J. Polym. Sci. Polym. Phys. Ed. 1985, 23, 1585.
Yeates, S. G.; Booth, C. Eur. Polym. J. 1985, 21, 217.
Campbell, C.; Viras, K.; Richardson, M. J.; Masters, A. J.;
Booth, C. Die Makromol. Chemie 1993, 194, 799.
Takizawa, K.; Nulwala, H.; Hu, J.; Yoshinaga, K.; Hawker, C.
J. J. Polym. Sci. Part A Polym. Chem. 2008, 46, 5977.
Mnyukh, Y. V. J. Struct. Chem. 1960, 1, 346.
Okihara, T.; Tsuji, M.; Kawaguchi, A.; Katayama, K.-I.;
Tsuji, H.; Hyon, S.-H.; Ikada, Y. J. Macromol. Sci. Part B
1991, 30, 119.
Karstedt, B. D. Platinum complexes of unsaturated
siloxanes and platinum containing organopolysiloxanes.
US3775452, 1973.
Strobl, G.; Ewen, B.; Fischer, E. W.; Piesczek, W. J. Chem.
Phys. 1974, 61, 5250.
AUTHOR INFORMATION
Corresponding Author
(29)
*e.w.meijer@tue.nl
(
30)
Notes
The authors declare no competing financial interests.
(31)
32)
(
ACKNOWLEDGMENT
This work is financed by the Royal Netherlands Academy of
Arts and Sciences and the Dutch Ministry of Education,
Culture and Science (Gravity program 024.001.035).
(33)
(
34)
REFERENCES
(35)
(36)
(37)
(38)
(39)
Ungar, G. J. Phys. Chem. 1983, 87, 689.
(
(
(
1)
2)
3)
Leibler, L. Macromolecules 1980, 13, 1602.
Bates, C. M.; Bates, F. S. Macromolecules 2017, 50, 3.
Schacher, F. H.; Rupar, P. a; Manners, I. Angew. Chemie Int.
Ed. 2012, 51, 7898.
Sirota, E.; Singer, D. J. Chem. Phys. 1994, 101, 10873.
Wentzel, N.; Milner, S. T. J. Chem. Phys. 2010, 132, 44901.
Tsuji, H. Macromol. Biosci. 2005, 5, 569.
Muller, A. Proc. R. Soc. A Math. Phys. Eng. Sci. 1928, 120,
437.
Smith, A. E. J. Chem. Phys. 1953, 21, 2229.
Lynd, N. A.; Hamilton, B. D.; Hillmyer, M. A. J. Polym. Sci.
Part B Polym. Phys. 2007, 45, 3386.
Hashimoto, T.; Tanaka, H.; Hasegawa, H. Macromolecules
1985, 18, 1864.
Hosemann, R.; Bagchi, S. N. Direct Analysis of Diffraction
by Matter; North-Holland Publishing: Amsterdam, 1962.
(
4)
Sinturel, C.; Bates, F. S.; Hillmyer, M. A. ACS Macro Lett.
2015, 4, 1044.
(40)
(41)
(
(
5)
6)
Hawker, C. J. Science 2005, 309, 1200.
van Genabeek, B.; de Waal, B. F. M.; Gosens, M. M. J.; Pitet,
L. M.; Palmans, A. R. A.; Meijer, E. W. J. Am. Chem. Soc.
(42)
(43)
2016, 138, 4210.
(
(
7)
8)
van Genabeek, B.; de Waal, B. F. M.; Ligt, B.; Palmans, A. R.
A.; Meijer, E. W. ACS Macro Lett. 2017, 6, 674.
Oschmann, B.; Lawrence, J.; Schulze, M. W.; Ren, J. M.;
Anastasaki, A.; Luo, Y.; Nothling, M. D.; Pester, C. W.;
ACS Paragon Plus Environment

Page 5 of 8
Journal of the American Chemical Society
Insert Table of Contents artwork here
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
5
ACS Paragon Plus Environment

Journal of the American Chemical Society
Page 6 of 8
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
Figure 1
1
75x43mm (300 x 300 DPI)
ACS Paragon Plus Environment

Page 7 of 8
Journal of the American Chemical Society
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Figure 2
270x228mm (300 x 300 DPI)
ACS Paragon Plus Environment

Journal of the American Chemical Society
Page 8 of 8
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
Table of Content
8
2x44mm (300 x 300 DPI)
ACS Paragon Plus Environment