Synthesis of a photoactive gemini surfactant and its use in AGET ATRP miniemulsion polymerisation and UV curing

Article abstract of DOI:10.2478/s11696-013-0420-y

A novel photoactive gemini surfactant was easily synthesised in high yields. The multi-functional molecule can be used as a gemini surfactant, a benzophenone type photoinitiator, and as an ATRP initiator. Poly(methyl methacrylate) (PMMA) and poly(methyl m

Full text of DOI:10.2478/s11696-013-0420-y

Chemical Papers
DOI: 10.2478/s11696-013-0420-y
ORIGINAL PAPER
Synthesis of a photoactive gemini surfactant and its use in AGET
ATRP miniemulsion polymerisation and UV curing
Chuan-Jie Cheng*, Xiong-Xiong Bai, Wu-Qin Fan, Hai-Ming Wu, Liang Shen*,
Qing-Hua Huang, Yuan-Ming Tu
Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science & Technology Normal University,
Fenglin Street, Nanchang, Jiangxi 330013, China
Received 10 December 2012; Revised 4 April 2013; Accepted 10 April 2013
A novel photoactive gemini surfactant was easily synthesised in high yields. The multi-functional
molecule can be used as a gemini surfactant, a benzophenone type photoinitiator, and as an ATRP
initiator. Poly(methyl methacrylate) (PMMA) and poly(methyl methacrylate)-block-poly(allyl
methacrylate) (PMMA-b-PAMA) were prepared using the photoactive gemini surfactant as an
ATRP initiator under soap-free miniemulsion polymerisation conditions. Kinetic results of the
miniemulsion polymerisation of methyl methacrylate (MMA) indicate that the reaction has con-
trolled/living characteristics. UV curing was performed by irradiation of the linear PMMA-b-PAMA
polymer, in which PMMA-b-PAMA containing a benzophenone moiety functioned as a macromolec-
ular photoinitiator.
c
ꢀ 2013 Institute of Chemistry, Slovak Academy of Sciences
Keywords: gemini surfactant, photoinitiator, activator generated by electron transfer atom trans-
fer radical polymerisation (AGET ATRP), miniemulsion polymerisation, soap-free
Introduction
vinyl monomers and reaction systems, tolerance to
many functional groups, etc. (Matyjaszewski, 2012;
Jiang et al., 2012; Zhai et al., 2012; Lou & Shipp, 2012;
Bai et al., 2011, 2012; Jakubowski & Matyjaszewski,
2005; Miao et al., 2012).
Controlled/living radical polymerisation (L/CRP)
has drawn great attention in recent years due to
its significant academic value and promising indus-
trial applications (Braunecker & Matyjaszewski, 2007;
Chu et al., 2012; Zhang et al., 2009; Destarac, 2010).
Many functional polymers and materials were pre-
pared by this versatile technique, e.g. polymer brushes
(Tsujii et al., 2006), telechelic polymers (Tasdelen
et al., 2011), stimuli-responsive polymers (Yan et
al., 2011), photoelectric functional molecules (Zhu et
al., 2011; Shen et al., 2009), functional biomacro-
molecules (Benoit et al., 2011), etc. Among various
L/CRP methods, atom transfer radical polymerisa-
tion (ATRP) and a recently developed activator gen-
erated by electron transfer for atom transfer radical
polymerisation (AGET ATRP) are prominent due to
their advantages such as easy manipulation, absence
of conventional radical initiator, adaptability to most
With the increasing global environmental protec-
tion pressure on chemical industries, people are seek-
ing safer and environmentally friendly reagents as well
as solvents or media to meet the demand of “green
chemistry”. The most preferable reaction medium is
water which is safe, nontoxic, cheap, and eco-friendly
(Lindstr¨om, 2007). For ATRP reactions in aqueous
systems, the miniemulsion polymerisation approach is
preferred; its controlled/living characteristics are best
compared with those of emulsion polymerisation and
microemulsion polymerisation methods (Mincheva et
al., 2009; Oh et al., 2009; Cheng et al., 2011a). How-
ever, to stabilise the dispersion system in conven-
tional emulsion polymerisation, small molecular emul-
sifiers are usually used, these are only physically ad-
*Corresponding author, e-mail: chengcj530@gmail.com; shenliang00@tsinghua.org.cn

ii
C. J. Cheng et al./Chemical Papers
sorbed on the particle which can desorb from the
polymer product or migrate to the polymer surface
thus affecting the surface and electrical properties
of the final polymer product. To overcome the dis-
advantages of small molecular emulsifiers, reactive
and macromolecular emulsifiers have been developed
in recent years (Cheng et al., 2011b; Basinska &
Slomkowski, 2012). Reactive or polymeric emulsifiers
can act as a macromonomer, inimer, or a transfer
agent in the L/CRP reactions. For example, Li et al.
(2009) used amphiphilic poly(ethylene oxide)-block-
poly(butyl methacrylate) with a chloro end group
(PEO-b-PBMA-Cl) to polymerise butyl methacrylate
(BMA) and ethylene glycol dimethacrylate (EGDMA)
to obtain a shell-crosslinked nanocapsule. Recently,
our research group introduced the synthesis and appli-
cation of an anionic surface-active ATRP initiator of
emulsion polymerisation of MMA, in which no other
emulsifiers were needed (Cheng et al., 2010).
Photocuring technology utilises light (e.g., UV or
visible light) to initiate and promote radical or ionic
polymerisation. This method is advantageous over
thermal curing in energy saving, safety, high reaction
rate, etc. (Yagci et al., 2010; Yilmaz et al., 2011; Eriks-
son et al., 2010). Thus, the technology is extensively
studied and applied in photocured coatings (Chen et
al., 2011), photocured printing inks (Lin et al., 2012),
and dental materials (Brandt et al., 2011).
Gemini surfactant is a special surfactant with two
hydrophilic “heads” and two hydrophobic hydrocar-
bon “tails”; its symmetrical structure provides it with
some unique properties such as low critical micelle
concentration (CMC) and high capability of lower-
ing surface tension (Wang, et al., 2012; Jahan et
al., 2009; Zana, 2002). In our recent work, a gem-
ini surface-active ATRP initiator was synthesised and
used in miniemulsion polymerisation of MMA with-
out any other emulsifier involved, and the resulting
latex was stable enough to stand for at least half a
year (Cheng et al., 2013). Herein, a facile synthesis
of a photoactive gemini surfactant is reported. To the
best of our knowledge, there are no reports on such a
multi-functional molecule or similar ones except in our
previous work (Cheng et al., 2013). There are three as-
pects concerning the application of the new surfactant:
i) gemini surfactant that can be used in miniemulsion
polymerisation; ii) ATRP initiator of the correspond-
ing polymers formation; iii) reactive benzophenone-
type photoinitiator in UV curing for the preparation
of UV cured resins.
N,N-dimethylethanolamine, dichloromethane, copper
(II) bromide, ascorbic acid (AA), N,N-dimethyldo-
decylamine (DMDA), and 6-(prop-2-enoyloxy)hexyl
prop-2-enoate (1,6-hexanediol diacrylate, HDDA) of
AR grade were used directly as received from Sino-
pharm Chemical Reagent Co. (SCRC, China). Tetra-
hydrofuran (THF) (SCRC, China) of AR grade purity
used as an eluent for neutral Al2O3 column separation
and of chromatographic purity used for gel perme-
ation chromatography (GPC), respectively, was used
as received. Methyl methacrylate (MMA) monomer
was purified by stirring with a 5 mass % aqueous
NaOH solution for 30 min, washing with deionised wa-
ter, and distillation under reduced pressure to remove
the inhibitor prior to use. Allyl methacrylate (AMA)
monomer was purified analogously but its instability
and higher boiling point were considered. Therefore, it
was finally purified on a neural Al2O3 column instead
of distillation.
1H (400 MHz) and 13C (100 MHz) NMR spectra
of the intermediates were recorded on a Bruker AV
400 MHz spectrometer using CDCl3 (unless specified
otherwise) as a solvent and tetramethylsilane (TMS)
as an internal standard. FTIR spectra (in KBr pellet)
were measured on a Bruker V70 FTIR spectropho-
tometer. Critical micelle concentration (CMC) of the
gemini surfactant was determined on a BZY-2 sur-
face tension meter. Gel permeation chromatography
(GPC) was performed on an HP 1100 HPLC equipped
with a Waters 2414 refractive index detector and three
Styragel HR 2, HR 4, HR 5 of 300 mm × 7.5 mm
columns (packed with 5 mm particles of different pore
size). The column packing allowed the separation of
polymers over a wide molecular mass range of 500–
1000000 Da. THF was used as the eluent at the flow
rate of 1 mL min−1 at 40◦C. PMMA standards were
used as the reference. Monomer conversion was deter-
mined by gravimetry. UV curing tests were performed
on an RW-UV AH400a UV curing meter.
Preparation of photoactive gemini surfactant I
2-(Dimethylamino)ethyl 2-bromo-2-methylpropa-
noate (II) was synthesised using the previously de-
scribed method (Cheng et al., 2013). Bis[4-(bromo-
methyl)phenyl]methanone (4,4ꢀ-di(bromomethyl)ben-
zophenone, III) was prepared by a known procedure
(Zheng et al., 2011) as follows: Bis(4-methylphenyl)
methanone (1.50 g, 7.1 mmol) and UHP (1.47 g,
15.7 mmol) were dissolved in CH2Cl2 (20 mL) and
the solution was heated to reflux under the irradia-
tion of visible light (100 W of electric lamp). Aqueous
HBr (48 mass % solution, 2.9 mL, 14.3 mmol) was
then added dropwise within about 20 min and the
reaction mixture was refluxed for additional 50 min
followed by the addition of water (20 mL). The or-
ganic phase was separated, washed with brine, dried
with anhydrous Na2SO4, filtered and the solvent was
Experimental
Materials and methods
Bis(4-methylphenyl)methanone (4,4ꢀ-dimethylben-
zophenone), carbamide peroxide (urea hydrogen per-
oxide, UHP), 2-bromo-2-methylpropanoyl bromide,

C. J. Cheng et al./Chemical Papers
iii
Fig. 1. Synthesis of the photoactive gemini surfactant I. Reaction conditions: i) Et3N, CH2Cl2, rt, overnight, 86 %; ii) 48 % aq.
HBr, UHP, CH2Cl2, light irradiation, reflux, 50 min, 46 %; iii) acetone, rt, 15 h, 86 %.
evaporated to give a white solid. Recrystallisation
from CH2Cl2/EtOH afforded pure product III (1.20 g,
46 %). M.p. 120–122◦C; IR, ν˜/cm−1: 3051, 1670, 1602,
was dried in a ventilation oven at 40◦C until constant
mass was achieved. The crude polymer product was
dissolved in THF and purified on a neutral Al2O3 col-
umn to remove possible copper residues.
1
1587, 1410, 850, 609; H NMR (400 MHz, CDCl3): δ
7.77 (d, 4H, J = 8.00 Hz), 7.50 (d, 4H, J = 7.92 Hz),
4.53 (s, 4H); 13C NMR (100 MHz, CDCl3): δ 195.5,
142.7, 137.6, 130.9, 129.5, 32.6.
UV curing of PMMA-b-PAMA
Intermediate III (2.20 g, 6 mmol) was dissolved
in acetone (20 mL), followed by the addition of II
(3.33 g, 14 mmol) and stirring the mixture at ambient
temperature for 15 h in N2 atmosphere. The reaction
mixture was filtered, the filter cake (white solid) was
triturated in anhydrous diethyl ether and the result-
ing solid was dried in a vacuum drying oven at 60◦C
to give the photoactive gemini surfactant I (4.37 g,
86.4 %). M.p. 109–111◦C; IR, ν˜ /cm−1: 3002, 2975,
1740, 1660, 1611, 1464, 1419, 1275, 1162, 1110, 934,
The PMMA-b-PAMA polymer (1.0 g) was dis-
solved in THF (10 mL) followed by an addition of
HDDA (0.1 g) and DMDA (0.03 g). The solution was
spin-coated on a glass plate with the rotation speed of
1500 min−1 for 1 min, and the coated layer was dried
at ambient temperature to form a film. After coating,
the plate was irradiated for 15 s by UV light (365 nm,
400 W) at the distance of 5 cm.
Results and discussion
1
872; H NMR (400 MHz, DMSO): δ 7.89 (d, 4H, J =
7.80 Hz), 7.81 (d, 4H, J = 7.84 Hz), 4.82 (s, 4H), 4.70
Synthesis and properties of photoactive gemini
surfactant (I)
(m, 4H), 3.83 (m, 4H), 3.13 (s, 12H), 1.95 (s, 12H); 13
C
NMR (100 MHz, D2O): δ 199.1, 172.9, 138.8, 133.7,
132.2, 131.2, 68.9, 63.2, 60.0, 56.4, 51.1, 30.0.
Complete NMR spectra of compounds I, II, and
III are available in the Supplementary data file.
Synthesis of the gemini surfactant I from a tertiary
amine (II ) and bis[4-(bromomethyl)phenyl]methan-
one (III ) is depicted in Fig. 1. In the first step, an
esterification reaction between 2-bromo-2-methylpro-
panoyl bromide and N,N-dimethylethanolamine in the
presence of triethyl amine gave intermediate II in a
86 % yield. Subsequently, compound III was prepared
from bis(4-methylphenyl)methanone by bromination
with aqueous HBr and UHP under visible light irradia-
tion. The method is cost-effective, highly efficient, and
avoids the use of toxic and corrosive bromine (Zheng,
et al., 2011).
One of the functions of surfactants is to decrease
the surface tension; and the higher the concentration
of the surfactants, the lower the surface tension of sub-
stances. When the concentration is increased to the
critical micelle concentration (CMC), the surface ten-
sion is almost constant. According to this principle,
surface tension was determined by preparing aqueous
solutions of I with different concentrations. The plot
of surface tension versus concentration is presented in
Fig. 2. As it can be seen, the surface tension decreased
rapidly with the increasing concentration of I; how-
Soap-free miniemulsion copolymerisation of
MMA and AMA using the photoactive gemini
surfactant I
Gemini surfactant I (1.287 g, 1.5 mmol), CuBr2
(catalyst) (0.223 g, 1 mmol), DMDA (ligand) (0.854 g,
4 mmol), MMA (14.02 g, 140 mmol), and deionised
water (50 mL) were mixed in a 100 mL three-necked
flask and the mixture was ultrasonicated for 30 min
to form a pre-emulsion. The pre-emulsion was purged
with N2 for 15 min and the flask was sealed and
heated to 60◦C on an oil bath. Ascorbic acid (0.396 g,
2 mmol) dissolved in deionised water (5 mL) was then
added by a syringe to initiate the reaction, and sam-
ples were withdrawn periodically during the reaction.
After 5 h, an additional portion of monomer AMA
(7.57 g, 60 mmol) was introduced into the reaction
mixture and the reaction was run for another 4 h
to complete the polymerisation. The resulting latex

iv
C. J. Cheng et al./Chemical Papers
Table 1. AGET atom transfer radical miniemulsion polymerisation of MMA at 60◦C using I as both an initiator and a stabiliser
and ascorbic acid (AA) as a reducing agenta
Entry
Time/h
Conversionb/%
Mn(th)c/(g mol−1
)
Mn(GPC)d/(g mol−1
)
PDI
ln(c0(M)/c(M))
1
2
3
4
5
6
7
8
9
0.5
1
1.5
2
2.5
3
3.5
4
21.1
40.1
55.4
64.3
74.0
82.1
84.8
88.1
90.0
2774
4522
5941
6730
7649
8386
8646
8938
9122
3300
4900
6800
7200
8000
8800
8900
9000
9300
1.37
1.35
1.35
1.32
1.33
1.30
1.29
1.27
1.27
0.24
0.51
0.81
1.02
1.35
1.71
1.89
2.12
2.30
5
a) No additional emulsifier was required in the whole process of miniemulsion polymerisation; b) conversion was determined by
gravimetric method; c) theoretical number-average molecular mass (Mn(th)) was calculated from the experimentally determined
conversions; d) experimental number-average molecular mass (Mn(GPC)) was measured by gel permeable chromatography (GPC)
using PMMA standards.
Fig. 3. Monomer conversion ( ) and ln(c0(M)/c(M)) ( ) as a
•
function of the reaction time.
Fig. 2. Dependence of surface tension on the concentration of
I.
factant, ATRP initiator, and a photoinitiator. First,
miniemulsion polymerisation of MMA, using I as both
an emulsifier and an AGET ATRP initiator, was stud-
ied. Based on our previous work, DMDA was se-
lected as both the ligand and the co-emulsifier for the
AGET ATRP miniemulsion polymerisation (Cheng et
al., 2011b). Mole ratio of the reagents was optimised
as n(I ) : n(CuBr2) : n(DMDA) : n(AA) : n(MMA)
= 1.5 : 1 : 4 : 2 : 140, and the reaction was per-
formed at 60◦C. Kinetic data of the MMA polymeri-
sation are listed in Table 1, and the dependence of
conversion, ln(c0(M)/c(M)), versus time is shown in
Fig. 3. Conversion increased smoothly with the in-
creasing reaction time, and conversion higher than
90 % was obtained within about 5 h. The linear re-
lationship between ln(c0(M)/c(M)) and the reaction
time indicates that the polymerisation followed the
first-order kinetic law and the concentration of prop-
agating radicals during the polymerisation was nearly
constant (Fig. 3). Fig. 4 shows the relationship of
molecular mass (Mn), polydispersity index (PDI), and
monomer conversion. Mn of PMMA increased almost
linearly with the monomer conversion, indicating the
controlled character of the miniemulsion polymerisa-
tion. In addition, the relatively low PDI (< 1.4) is an-
other proof of the controlled character of the reaction
(Table 1).
ever, when the concentration increased to 5 mmol L−1
and higher, the curve became almost smooth. So, the
CMC value of I is about 5 mmol L−1
.
The hydrophilic–lipophilic balance (HLB) number
is another important parameter of surfactants. The
HLB value of a surfactant can be calculated from the
corresponding CMC. For a surfactant of a quaternary
ammonium salt like I, the HLB can be calculated by
Eq. (1), where the c(CMC) unit is mol L−1 (Zhou &
Cui, 2001). As the CMC value of surfactant I is 0.005
mol L−1, its calculated HLB value is 40.229, indicat-
ing highly hydrophilic properties of I. Furthermore,
solubility of I in water was tested, and it was found
that 27.3 g of I can be dissolved in 100 mL of deionised
water at ambient temperature.
HLB = 1.155 log(c(CMC)) + 42.887
(1)
Preparation of PMMA-b-PAMA via soap-free
AGET ATRP miniemulsion polymerisation
Multi-functional compound I can act as a sur-

C. J. Cheng et al./Chemical Papers
v
uct was insoluble in THF as well as in other com-
mon solvents, indicating that a nonnegligible amount
of allylic double bonds underwent the reactions. To
solve this problem, copolymerisation of MMA and
AMA was performed. After several controlled exper-
iments (by emulsion polymerisation), the mole ratio
MMA/AMA of 7 : 3 was adopted, and flocculation
was neglected under these conditions. At first, MMA
was polymerised to let the conversion reach about
90 % in 5 h. Then, the AMA monomer was added to
the reaction system and the polymerisation was run
for additional 4 h. In this way, PMMA-b-PAMA was
prepared in one pot, and the “living” characteristics
of the miniemulsion polymerisations were also proven
(Fig. 5) (Shu et al., 2011).
Fig. 4. Dependence of molecular mass (Mn(GPC)) ( ) and
polydispersity index (PDI) ( ) on monomer conver-
•
sion.
1H NMR spectrum confirming the formation of
block copolymer PMMA-b-PAMA is illustrated in
Fig. 6. Proton signals of both MMA and AMA units
were found in the spectrum. Ha and Hb represent the
protons on aryl rings of benzophenone, and their num-
ber was estimated as eight (4 Ha and 4 Hb). The num-
ber of protons of typical functional groups in the block
copolymer can be determined based on the number of
aryl protons. Hc and Hd represent vinyl protons of al-
lyl groups. The number of Hc was about 65, and that
of Hd 130, indicating that about 65 of AMA units
Then, polymerisation of AMA utilising I as both
an emulsifier and an AGET ATRP initiator was at-
tempted. AMA is a special monomer that has two
—
types of C C double bonds with different reactivity.
—
—
—
The C C double bond of methacrylate is more re-
active and it is expected to undergo ATRP reactions,
—
while the less reactive allylic C C double bonds re-
—
main unchanged. In a control experiment, when only
AMA was polymerised in emulsion, a cross-linking
side-reaction occurred and the resulting polymer prod-
Fig. 5. One-pot preparation of PMMA-b-PAMA. Reaction conditions: i) MMA, CuBr2, AA, deionised water, 60◦C, 5 h; ii) AMA,
CuBr2, AA, deionised water, 60◦C, 4 h.

vi
C. J. Cheng et al./Chemical Papers
Fig. 6. 1H NMR spectrum of block copolymer PMMA-b-PAMA.
are present in the copolymer. The signal designated
as He at δ = 4.40 belongs the protons of CH2 in al-
lyl groups. The peak at δ = 3.53 (Hf ) corresponds
to the proton of methoxy groups of MMA units, and
the presence of about 790 protons in the spectra sug-
gests that there are about 260 MMA units in the
copolymer. Therefore, the molecular mass of PMMA-
b-PAMA can be estimated as Mn(NMR) = Mn(init)
+ (65 × M(AMA)) + (260 × M(MMA)) = 844 +
(65 × 126) + (260 × 100) = 35034 ≈ 35000.
GPC spectra of PMMA and PMMA-b-PAMA are
shown in Fig. 7 to further verify the formation of the
block copolymer. The number-average molecular mass
of PMMA-b-PAMA was higher than that of PAMA,
indicating the polymerisation of the AMA monomer
based on the PMMA macroinitiator to form the cor-
responding block copolymer. The molecular mass of
PMMA-b-PAMA obtained from the GPC spectra is
Fig. 7. GPC spectra of PMMA-b-PAMA (Mn = 11000 Da, PDI
= 1.13) (a) and PMMA (Mn = 9300 Da, PDI = 1.27)
(b).
none photoinitiator and many allyl groups are present;
this unique structure enables further curing of the
polymer under UV irradiation. Because benzophenone
belongs to hydrogen-abstracting photoinitiators, ter-
tiary amine is required for UV curing. Thus, DMDA
was used as the corresponding tertiary amine, and it
accounted for 3 mass % of the PMMA-b-PAMA poly-
mer. HDDA was chosen as the diluter in the amount
of 10 mass % based on PMMA-b-PAMA. After the
1
inconsistent with that obtained from H NMR, which
can be attributed to an integration error in NMR.
UV curing of the prepared PMMA-b-PAMA
In the linear PMMA-b-PAMA polymer, benzophe-

C. J. Cheng et al./Chemical Papers
vii
to the formulation, its properties improved but the
film’s surface was still brittle (Entry 2, Table 1). Rel-
atively good toughness was obtained when 10 mass %
of HDDA were used (Entry 3, Table 1). However, when
20 mass % of HDDA were added, the film showed very
low hardness.
Conclusions
A photoactive gemini surfactant was prepared in
a 86 % yield under mild conditions. This novel multi-
functional molecule was successfully used as an emulsi-
fier, ATRP initiator, and a type-II photoinitiator. Lin-
ear PMMA as well as PMMA-b-PAMA were prepared
by employing the functional molecule as an ATRP
initiator generated by electron transfer (AGET) for
atom transfer miniemulsion polymerisation, in which
no other emulsifiers were involved. The polymerisa-
tion followed the first-order kinetic law and showed
controlled/living characteristics. UV irradiation of
PMMA-b-PAMA within 15 s afforded the correspond-
ing UV cured polymer which was almost insoluble in
common organic solvents. The novel photoactive gem-
ini surfactant is expected to provide more functional
macromolecules.
Fig. 8. Comparison of IR spectra of PMMA-b-PAMA before
(a) and after UV irradiation (b).
Table 2. Effect of the HDDA amount on the properties of UV
cured polymer filmsa
Properties of
UV cured polymer films
Entry
HDDAb/mass %
1
2
3
4
0
5
10
20
very brittle, light yellow
brittle, light yellow
good toughness, light yellow
too soft, low hardness
Acknowledgements. This work was financially supported by
the Natural Science Foundations of China (nos. 21264008 and
51063002) and the Natural Science Foundations of the Jiangxi
Province (no. 2009GZH0035).
a) Amount of DMDA co-photoinitiator was 3 mass % based on
compound I; UV irradiation time was 15 s; b) amount of the
HDDA diluter based on compound I.
Supplementary data
Supplementary data associated with this article
can be found in the online version of this paper (DOI:
10.2478/s11696-013-0420-y).
UV irradiation for 15 s, a film was obtained. Com-
parison of the IR spectra of PMMA-b-PAMA before
and after the UV curing (Fig. 8) showed that there
is a peak at 3086 cm−1 before the UV curing, rep-
resenting the signal of the vinylic C—H bond. The
peak at 3086 cm−1 disappeared after the UV irradia-
References
Bai, L., Zhang, L., Zhang, Z., Zhu, J., Zhou, N., Cheng, Z.,
& Zhu, X. (2011). Alumina additives for fast iron-mediated
AGET ATRP of MMA using onium salt as ligand. Journal
of Polymer Science Part A: Polymer Chemistry, 49, 3970–
3979. DOI: 10.1002/pola.24837.
Bai, L., Zhang, L., Cheng, Z., & Zhu, X. (2012). Activa-
tors generated by electron transfer for atom transfer rad-
ical polymerization: recent advances in catalyst and poly-
mer chemistry. Polymer Chemistry, 3, 2685–2697. DOI:
10.1039/c2py20286g.
Basinska, T., & Slomkowski, S. (2012). Design of polyglycidol-
containing microspheres for biomedical applications. Chemi-
cal Papers, 66, 352–368. DOI: 10.2478/s11696-011-0122-2.
Benoit, D. S. W., Srinivasan, S., Shubin, A. D., & Stayton, P. S.
(2011). Synthesis of folate-functionalized RAFT polymers for
targeted siRNA delivery. Biomacromolecules, 12, 2708–2714.
DOI: 10.1021/bm200485b.
Brandt, W. C., de Oliveira Tomaselli, L., Correr-Sobrinho, L.,
& Sinhoreti, M. A. C. (2011). Can phenyl-propanedione in-
fluence Knoop hardness, rate of polymerization and bond
strength of resin composite restorations? Journal of Den-
tistry, 39, 438–447. DOI: 10.1016/j.jdent.2011.03.009.
Braunecker, W. A., & Matyjaszewski, K. (2007). Controlled/
—
tion, indicating that most allylic C C double bonds
—
underwent radical reactions under the UV curing con-
ditions. Changes in the polymer’s solubility also con-
firmed the effect of UV curing. Before UV irradiation,
the PMMA-b-PAMA polymer (1.0 g) dissolved in THF
(20 mL) in 30 min, while the cured PMMA-b-PAMA
polymer (1.0 g) cannot be dissolved in THF (20 mL)
even after 24 h.
Control experiments were performed to illustrate
the role of the HDDA diluter in the UV curing of the
PMMA-b-PAMA polymer (Table 2). During UV cur-
ing, it is usually necessary to use a diluter to adjust
the curing rate, viscosity of the system, and film prop-
erties. In the control experiment, properties of the film
remained almost unchanged without HDDA after the
UV irradiation for 15 s, which indicated that the UV
curing rate is very low in the absence of a diluter (En-
try 1, Table 1). When 5 mass % of HDDA were added

viii
C. J. Cheng et al./Chemical Papers
living radical polymerization: Features, developments, and
perspectives. Progress in Polymer Science, 32, 93–146. DOI:
10.1016/j.progpolymsci.2006.11.002.
metal catalyst concentrations. ChemPhysChem, 13, 3257–
3261. DOI: 10.1002/cphc.201200166.
Matyjaszewski, K. (2012). Atom transfer radical polymeriza-
tion (ATRP): Current status and future perspectives. Macro-
molecules, 45, 4015–4039. DOI: 10.1021/ma3001719.
Chen, Z., Wu, J., Fernando, S., & Jagodzinski, K. (2011).
Soy-based, high biorenewable content UV curable coat-
ings. Progress in Organic Coatings, 71, 98–109. DOI:
10.1016/j.porgcoat.2011.01.004.
Cheng, C., Shu, J., Gong, S., Shen, L., Qiao, Y., & Fu, C.
(2010). Synthesis and use of a surface-active initiator in
emulsion polymerization under AGET and ARGET ATRP
conditions. New Journal of Chemistry, 34, 163–170. DOI:
10.1039/b9nj00307j.
Miao, J., Jiang, H., Zhang, L., Wu, Z., Cheng, Z.,
Zhu, X. (2012). AGET ATRP of methyl methacrylate via
bimetallic catalyst. RSC Advances, 2, 840–847. DOI:
&
a
10.1039/c1ra00456e.
Mincheva, R., Paneva, D., Mespouille, L., Manolova, N.,
Rashkov, I., & Dubois, P. (2009). Optimized water-based
ATRP of an anionic monomer: Comprehension and proper-
ties characterization. Journal of Polymer Science Part A:
Polymer Chemistry, 47, 1108–1119. DOI: 10.1002/pola.23
222.
Cheng, C., Shen, L., Fu, Q., & Gong, S. (2011a). Soap-free
living/controlled radical emulsion polymerization. Progress
in Chemistry, 23, 791–799. (in Chinese)
Oh, J. K., Perineau, F., Charleux, B., & Matyjaszewski, K.
(2009). AGET ATRP in water and inverse miniemulsion:
A facile route for preparation of high-molecular-weight bio-
compatible brush-like polymers. Journal of Polymer Sci-
ence Part A: Polymer Chemistry, 47, 1771–1781. DOI:
10.1002/pola.23272.
Shen, L., Ma, C., Pu, S., Cheng, C., Xu, J., Li, L., & Fu,
C. (2009). Synthesis and properties of novel photochromic
poly(methyl methacrylate-co-diarylethene)s. New Journal of
Chemistry, 33, 825–830. DOI: 10.1039/b813901f.
Cheng, C., Fu, Q., Liu, Z., Shen, L., Qiao, Y., & Fu, C.
(2011b). Emulsifier-free synthesis of crosslinkable ABA tri-
block copolymer nanoparticles via AGET ATRP. Macro-
molecular Research, 19, 1048–1055. DOI: 10.1007/s13233-
011-1008-4.
Cheng, C. J., Fu, Q. L., Bai, X. X., Liu, S. J., Shen, L., Fan,
W. Q., & Li, H. X. (2013). Facile synthesis of gemini surface-
active ATRP initiator and its use in soap-free AGET ATRP
mini-emulsion polymerisation. Chemical Papers, 67, 336–
341. DOI: 10.2478/s11696-012-0271-y.
Shu, J., Cheng, C., Zheng, Y., Shen, L., Qiao, Y., & Fu, C.
(2011). “One pot” synthesis of fluorinated block copoly-
mers using a surface-active ATRP initiator under emulsion
polymerization conditions. Polymer Bulletin, 67, 1185–1200.
DOI: 10.1007/s00289-011-0446-7.
Tsujii, Y., Ohno, K., Yamamoto, S., Goto, A., & Fukuda, T.
(2006). Structure and properties of high-density polymer
brushes prepared by surface-initiated living radical polymer-
ization. In R. Jordan (Ed.), Surface-initiated polymerization
I (Advances in polymer science series, Vol. 197, pp. 1–45).
Chu, D. S. H., Schellinger, J. G., Shi, J., Convertine, A. J.,
Stayton, P. S., & Pun, S. H. (2012). Application of living free
radical polymerization for nucleic acid delivery. Accounts of
Chemical Research, 45, 1089–1099. DOI: 10.1021/ar200242z.
Destarac, M. (2010). Controlled radical polymerization: Indus-
trial stakes, obstacles and achievements. Macromolecular Re-
action Engineering, 4, 165–179. DOI: 10.1002/mren.200900
087.
Eriksson, M., Boyer, A., Sinigoi, L., Johansson, M., Malmstr¨om,
E., Hult, K., Trey, S., & Martinelle, M. (2010). One-pot en-
zymatic route to tetraallyl ether functional oligoesters: Syn-
thesis, UV curing, and characterization. Journal of Polymer
Science Part A: Polymer Chemistry, 48, 5289–5297. DOI:
10.1002/pola.24328.
Jahan, N., Paul, N., Petropolis, C. J., Marangoni, D. G., &
Grindley, T. B. (2009). Synthesis of surfactants based on
pentaerythritol. I. Cationic and zwitterionic gemini surfac-
tants. The Journal of Organic Chemistry, 74, 7762–7773.
DOI: 10.1021/jo9018107.
Jakubowski, W., & Matyjaszewski, K. (2005). Activator gener-
ated by electron transfer for atom transfer radical polymer-
ization. Macromolecules, 38, 4139–4146. DOI: 10.1021/ma0
47389l.
Jiang, H., Zhang, L., Pan, J., Jiang, X., Cheng, Z., & Zhu,
X. (2012). Iron-mediated AGET ATRP of methyl methacry-
late using metal wire as reducing agent. Journal of Polymer
Science Part A: Polymer Chemistry, 50, 2244–2253. DOI:
10.1002/pola.26002.
Li, W., Matyjaszewski, K., Albrecht, K., & Mo¨ller, M. (2009).
Reactive surfactants for polymeric nanocapsules via inter-
facially confined miniemulsion ATRP. Macromolecules, 42,
8228–8233. DOI: 10.1021/ma901574y.
Lin, J., Wang, W., Wen, X., Cai, Z. Q., Pi, P., Zheng, D. F.,
Cheng, J., & Yang, Z. (2012). Thermal stability, curing ki-
netics and properties of polyurethanes system for in-mould
decoration ink. Pigment & Resin Technology, 41, 351–358.
DOI: 10.1108/03699421211274270.
Lindstro¨m, U. M. (Ed.) (2007). Organic reactions in water:
Principles, strategies and applications. Oxford, UK: Black-
well Publishing.
063.
Berlin, Germany: Springer. DOI: 10.1007/12
Tasdelen, M. A., Kahveci, M. U., & Yagci, Y. (2011). Telechelic
polymers by living and controlled/living polymerization
methods. Progress in Polymer Science, 36, 455–567. DOI:
10.1016/j.progpolymsci.2010.10.002.
Wang, H., Pan, Q., & Rempel, G. L. (2012). Organic solvent-
free catalytic hydrogenation of diene-based polymer nanopar-
ticles in latex form: Part I. Preparation of nano-substrate.
Journal of Polymer Science Part A: Polymer Chemistry, 50,
4656–4665. DOI: 10.1002/pola.26277.
Yagci, Y., Jockusch, S., & Turro, N. J. (2010). Photoinitiated
polymerization: Advances, challenges, and opportunities.
Macromolecules, 43, 6245–6260. DOI: 10.1021/ma1007545.
Yan, Q., Zhou, R., Fu, C., Zhang, H., Yin, Y., & Yuan,
J. (2011). CO2-responsive polymeric vesicles that breathe.
Angewandte Chemie International Edition, 50, 4923–4927.
DOI: 10.1002/anie.201100708.
Yilmaz, G., Beyazit, S., & Yagci, Y. (2011). Visible light induced
free radical promoted cationic polymerization using thioxan-
thone derivatives. Journal of Polymer Science Part A: Poly-
mer Chemistry, 49, 1591–1596. DOI: 10.1002/pola.24582.
Zana, R. (2002). Dimeric and oligomeric surfactants. Behav-
ior at interfaces and in aqueous solution: a review. Ad-
vances in Colloid and Interface Science, 97, 205–253. DOI:
10.1016/s0001-8686(01)00069-0.
Zhai, S., Shang, J., Yang, D., Wang, S., Hu, J., Lu, G.,
&
Huang, X. (2012). Successive SET-LRP and ATRP
synthesis of ferrocene-based PPEGMEA-g-PAEFC well-
defined amphiphilic graft copolymer. Journal of Polymer
Science Part A: Polymer Chemistry, 50, 811–820. DOI:
10.1002/pola.25836.
Lou, Q., & Shipp, D. A. (2012). Recent developments in atom
transfer radical polymerization (ATRP): Methods to reduce
Zhang, Y., Li, C., & Liu, S. (2009). One-pot synthesis of
ABC miktoarm star terpolymers by coupling ATRP, ROP,

C. J. Cheng et al./Chemical Papers
ix
and click chemistry techniques. Journal of Polymer Sci-
ence Part A: Polymer Chemistry, 47, 3066–3077. DOI:
10.1002/pola.23388.
Zheng, Y., Cheng, C. J., Huang, H. Q., Shen, L., Fu, C. Q., &
Qiao, Y. L. (2011). Fast synthesis of ATRP initiators with
photoinitiating activity by urea hydrogen peroxide method.
Chinese Journal of Synthetic Chemistry, 19, 376–378. (in
Chinese)
Zhou, J., & Cui, Y. (2001). Measurement and calculation of
HLB value of surfactants. I. The measurement of HLB value.
Speciality Petrochemicals, 2001, 11–14. (in Chinese)
Zhu, X., Zhou, N., Zhang, Z., Sun, B., Yang, Y., Zhu, J.,
& Zhu, X. (2011). Cyclic polymers with pendent carbazole
units: enhanced fluorescence and redox behavior. Ange-
wandte Chemie International Edition, 50, 6615–6618. DOI:
10.1002/anie.201101303.