Mesoporous silica nanoparticles/polymer hybrid materials were prepared via metal-free surface-initiated atom-transfer radical polymerization (SI-ATRP). Self-synthesized mesoporous SBA-15 with surface hydroxyl groups was modified with (3-aminopropyl)-triethoxysilane, followed by anchoring of the ATRP initiator α-bromoisobutyryl bromide onto the surface via amide reaction. The SI-ATRP of methyl methacrylate was then carried out with fluorescein (FL) as a photocatalyst and trimethylamine (TEA) as an electron donor under irradiation with blue light. Thus, polymer chains grew directly from mesoporous walls. The hybrid materials were characterized by gel permeation chromatography, N2 adsorption/desorption measurements, and thermogravimetric analysis. The effects of the ligand/photocatalyst molar ratios, solvent, and the monomer/initiator molar ratios on grafting density, molecular weight, and molecular-weight distribution were investigated. The results show that a higher TEA/FL ratio led to a higher reaction rate and better controllability of the polymerization but also to a lower grafting density. These properties were also affected by the solvent. With an increasing monomer/initiator molar ratio, the grafting rate, molecular weight, and grafting density exhibited increasing trends.

1.
M.
Krux
,
M.
Jaroniec
,
C. H.
Ko
 et al, “
Characterization of the porous structure of SBA-15
,”
BioMed Res. Int.
12
(
7
),
1961
1968
(
2000
).
2.
Y.
Liu
,
J.
Qiu
,
Y.
Jiang
 et al, “
Selective Ce(III) ion-imprinted polymer grafted on Fe3O4 nanoparticles supported by SBA-15 mesopores microreactor via surface-initiated RAFT polymerization
,”
Microporous Mesoporous Mater.
234
,
176
185
(
2016
).
3.
L.
Huang
,
J.
Wu
,
M.
Liu
 et al, “
Direct surface grafting of mesoporous silica nanoparticles with phospholipid choline-containing copolymers through chain transfer free radical polymerization and their controlled drug delivery
,”
J. Colloid Interface Sci.
508
,
396
404
(
2017
).
4.
H.
Long
,
M.
Liu
,
L.
Mao
 et al, “
Preparation and controlled drug delivery applications of mesoporous silica polymer nanocomposites through the visible light induced surface-initiated ATRP
,”
Appl. Surf. Sci.
412
,
571
577
(
2017
).
5.
L.
Mao
,
M.
Liu
,
L.
Huang
 et al, “
Photo-induced surface grafting of phosphorylcholine containing copolymers onto mesoporous silica nanoparticles for controlled drug delivery
,”
Mater. Sci. Eng. C
79
,
596
604
(
2017
).
6.
B. J.
Ji
,
J.
Park
, and
J.
Yi
, “
Preparation of polyelectrolyte-functionalized mesoporous silicas for the selective adsorption of anionic dye in an aqueous solution
,”
J. Hazard. Mater.
168
(
1
),
102
107
(
2009
).
7.
T.
Takei
,
K.
Yoshimura
,
Y.
Yonesaki
 et al, “
Preparation of polyaniline/mesoporous silica hybrid and its electrochemical properties
,”
J. Porous Mater.
12
(
4
),
337
343
(
2005
).
8.
L.
Zu
,
X.
Cui
,
Y.
Jiang
 et al, “
Preparation and electrochemical characterization of mesoporous polyaniline-silica nanocomposites as an electrode material for pseudocapacitors
,”
Materials
8
(
4
),
1369
(
2015
).
9.
K.
Li
,
J.
Jiang
,
S.
Tian
 et al, “
Polyethyleneimine–nano silica composites: A low-cost and promising adsorbent for CO2 capture
,”
J. Mater. Chem. A
3
(
5
),
2166
2175
(
2015
).
10.
A. M.
Liu
,
K.
Hidajat
,
S.
Kawi
 et al, “
A new class of hybrid mesoporous materials with functionalized organic monolayers for selective adsorption of heavy metal ions
,”
Chem. Commun.
230
(
13
),
1145
1146
(
2000
).
11.
S. S.
Park
and
C. S.
Ha
, “
Hollow mesoporous functional hybrid materials: Fascinating platforms for advanced applications
,”
Adv. Funct. Mater.
28
(
27
),
1703814
(
2018
).
12.
Y.
Zhao
,
Y.
Shen
, and
L.
Bai
, “
Effect of chemical modification on carbon dioxide adsorption property of mesoporous silica
,”
J. Colloid Interface Sci.
379
(
1
),
94
100
(
2012
).
13.
W.
Zhang
,
X.
Zhuang
,
X.
Li
 et al, “
Preparation and characterization of organic/inorganic hybrid polymers containing polyhedral oligomeric silsesquioxane via RAFT polymerization
,”
React. Funct. Polym.
69
(
2
),
124
129
(
2009
).
14.
M.
Chen
,
H.
Zhou
,
L.
Zhou
 et al, “
Confined polymerization: ARGET ATRP of MMA in the nanopores of modified SBA-15
,”
Polymer
114
,
180
188
(
2017
).
15.
F. A.
Zhang
,
D. K.
Lee
, and
T. J.
Pinnavaia
, “
PMMA–mesocellular foam silica nanocomposites prepared through batch emulsion polymerization and compression molding
,”
Polymer
50
(
20
),
4768
4774
(
2009
).
16.
F. A.
Zhang
,
D. K.
Lee
, and
T. J.
Pinnavaia
, “
PMMA/mesoporous silica nanocomposites: Effect of framework structure and pore size on thermomechanical properties
,”
Polym. Chem.
1
(
1
),
107
113
(
2010
).
17.
R.
Barbey
,
L.
Lavanant
,
D.
Paripovic
 et al, “
Polymer brushes via surface-initiated controlled radical polymerization: Synthesis, characterization, properties, and applications
,”
Chem. Rev.
109
(
11
),
5437
5527
(
2009
).
18.
S.
Yamamoto
,
M.
Ejaz
,
Y.
Tsujii
 et al, “
Surface interaction forces of well-defined, high-density polymer brushes studied by atomic force microscopy. 1. Effect of chain length
,”
Macromolecules
33
(
15
),
5608
5612
(
2000
).
19.
W. A.
Braunecker
and
K.
Matyjaszewski
, “
Controlled/living radical polymerization: Features, developments, and perspectives
,”
Prog. Polymer Sci.
32
(
1
),
93
146
(
2011
).
20.
H.
Blas
,
M.
Save
,
C.
Boissière
 et al, “
Surface-Initiated nitroxide-mediated polymerization from ordered mesoporous silica
,”
Macromolecules
44
(
8
),
2577
2588
(
2017
).
21.
C. J.
Hawker
,
A. W.
Bosman
, and
E.
Harth
, “
New polymer synthesis by nitroxide mediated living radical polymerizations
,”
Chem. Rev.
101
(
12
),
3661
3688
(
2001
).
22.
M.
Kamigaito
,
T. T.
Ando
, and
M.
Sawamoto
, “
Metal-catalyzed living radical polymerization
,”
Chem. Rec.
101
(
12
),
3689
3746
(
2001
).
23.
F.
Yu
,
X.
Tang
, and
M.
Pei
, “
Facile synthesis of PDMAEMA-coated hollow mesoporous silica nanoparticles and their pH-responsive controlled release
,”
Microporous Mesoporous Mater.
173
,
64
69
(
2013
).
24.
Y. K.
Chong
,
J.
Krstina
,
T. P. T.
Le
 et al, “
Thiocarbonylthio compounds [SC(Ph)S-R] in free radical polymerization with reversible addition-fragmentation chain transfer (RAFT polymerization). Role of the free-radical leaving group (R)
,”
Macromolecules
36
(
7
),
2256
2272
(
2003
).
25.
C. Y.
Hong
,
X.
Li
, and
C. Y.
Pan
, “
Grafting polymer nanoshell onto the exterior surface of mesoporous silica nanoparticles via surface reversible addition-fragmentation chain transfer polymerization
,”
Eur. Polym. J.
43
(
10
),
4114
4122
(
2007
).
26.
C. S.
Park
,
H. J.
Lee
,
A. C.
Jamison
 et al, “
Robust thick polymer brushes grafted from gold surfaces using bidentate thiol-based atom-transfer radical polymerization initiators
,”
ACS Appl. Mater. Interfaces
8
(
8
),
5586
5594
(
2016
).
27.
Y.
Song
,
G.
Ye
,
Y.
Lu
 et al, “
Surface-Initiated ARGET ATRP of poly(glycidyl methacrylate) from carbon nanotubes via bioinspired catechol chemistry for efficient adsorption of uranium ions
,”
ACS Macro Lett.
5
(
3
),
382
386
(
2016
).
28.
Y.
Chen
,
S.
Zhang
,
X.
Liu
 et al, “
Preparation of solution-processable reduced graphene oxide/polybenzoxazole nanocomposites with improved dielectric properties
,”
Macromolecules
48
(
2
),
365
372
(
2015
).
29.
L.
Cao
and
M.
Kruk
, “
Grafting of polymer brushes from nanopore surface via atom transfer radical polymerization with activators regenerated by electron transfer
,”
Polym. Chem.
1
(
1
),
97
101
(
2010
).
30.
Y.
Liu
,
X.
Miao
,
Z.
Jian
 et al, “
Polymer-grafted modification of activated carbon by surface-initiated AGET ATRP
,”
Macromol. Chem. Phys.
213
(
8
),
868
877
(
2012
).
31.
X.
Zhan
,
Y.
Yan
,
Q.
Zhang
 et al, “
A novel superhydrophobic hybrid nanocomposite material prepared by surface-initiated AGET ATRP and its anti-icing properties
,”
J. Mater. Chem. A
2
(
24
),
9390
9399
(
2014
).
32.
M. S.
Chen
,
L. M.
Qin
,
Y. L.
Liu
 et al, “
Controllable preparation of polymer brushes from mesoporous silica SBA-15 via surface-initiated ARGET ATRP
,”
Microporous Mesoporous Mater.
263
,
158
164
(
2018
).
33.
C.
Aydogan
,
G.
Yilmaz
, and
Y.
Yagci
, “
Synthesis of hyperbranched polymers by photoinduced metal-free ATRP
,”
Macromolecules
50
(
23
),
9115
9120
(
2017
).
34.
E. H.
Discekici
,
C. W.
Pester
,
N. J.
Treat
 et al, “
Simple benchtop approach to polymer brush nanostructures using visible-light-mediated metal-free atom transfer radical polymerization
,”
ACS Macro Lett.
5
(
2
),
258
262
(
2016
).
35.
Z.
Huang
,
Y.
Gu
,
X.
Liu
 et al, “
Metal-free atom transfer radical polymerization of methyl methacrylate with ppm level of organic photocatalyst
,”
Macromol. Rapid Commun.
38
(
10
), 1600461 (
2016
).
36.
X. D.
Liu
,
L. F.
Zhang
,
Z. P.
Cheng
 et al, “
Metal-free photoinduced electron transfer-atom transfer radical polymerization (PET-ATRP) via a visible light organic photocatalyst
,”
Polym. Chem.
7
(
3
),
689
700
(
2016
).
37.
X.
Pan
,
C.
Fang
,
M.
Fantin
 et al, “
Mechanism of photoinduced metal-free atom transfer radical polymerization: Experimental and computational studies
,”
J. Am. Chem. Soc.
138
(
7
),
2411
2425
(
2016
).
38.
N. J.
Treat
,
S.
Hazel
,
J. W.
Kramer
 et al, “
Metal-free atom transfer radical polymerization
,”
J. Am. Chem. Soc.
136
(
45
),
16096
16101
(
2014
).
39.
C. N.
Yan
,
Q.
Liu
,
L.
Xu
 et al, “
Photoinduced metal-free surface initiated ATRP from hollow spheres surface
,”
Polymers
11
(
4
),
599
(
2019
).
40.
J.
Yan
,
X.
Pan
,
M.
Schmitt
 et al, “
Enhancing initiation efficiency in metal-free surface-initiated atom transfer radical polymerization (SI-ATRP)
,”
ACS Macro Lett.
5
,
661
665
(
2016
).
41.
C.
Bian
,
Y. N.
Zhou
,
J. K.
Guo
 et al, “
Aqueous metal-free atom transfer radical polymerization: Experiments and model-based approach for mechanistic understanding
,”
Macromolecules
51
(
6
),
2367
2376
(
2018
).
42.
B. L.
Ramsey
,
R. M.
Pearson
,
L. R.
Beck
 et al, “
Photoinduced organocatalyzed atom transfer radical polymerization using continuous flow
,”
Macromolecules
50
(
7
),
2668
2674
(
2017
).
43.
M. D.
Ryan
,
R. M.
Pearson
,
T. A.
French
 et al, “
Impact of light intensity on control in photoinduced organocatalyzed atom transfer radical polymerization
,”
Macromolecules
50
(
12
),
4616
4622
(
2017
).
44.
L.
Ma
,
N.
Li
,
J.
Zhu
 et al, “
Visible light-induced metal free surface initiated atom transfer radical polymerization of methyl methacrylate on SBA-15
,”
Polymers
9
(
2
),
12
(
2017
).
45.
P.
Pasetto
,
H.
Blas
,
F.
Audouin
 et al, “
Mechanistic insight into surface-initiated polymerization of methyl methacrylate and styrene via ATRP from ordered mesoporous silica particles
,”
Macromolecules
42
(
16
),
5983
5995
(
2009
).
46.
C.
Huang
,
T.
Tassone
,
K.
Woodberry
 et al, “
Impact of ATRP initiator spacer length on grafting poly(methyl methacrylate) from silica nanoparticles
,”
Langmuir
25
(
23
),
13351
13360
(
2009
).
47.
C.
Staak
,
E.
Bulling
,
U.
Kämpe
 et al, “
The effect of [CuI]/[CuII] ratio on the kinetics and conformation of polyelectrolyte brushes by atom transfer radical polymerization
,”
Macromol. Rapid Commun.
27
(
19
),
1632
1636
(
2006
).
48.
X.
Pan
,
M.
Fantin
,
F.
Yuan
 et al, “
Externally controlled atom transfer radical polymerization
,”
Chem. Soc. Rev.
47
(
14
),
5457
5490
(
2018
).
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