N butyl acrylate

Acryloyl chloride, bis(cyclopentadienyl)titanium dichloride, 9-borabicyclo[3.3.1]nonane, 3-buten-3-ol, n-butyl acrylate, n-decan-1-ol, Dess-Martin periodinane, diethyl ether, diethylaluminium chloride, n-heptan-1-ol, 6-hepten-1-ol, 1,4-hexadiene, (E)-2-hexen-1-ol, (E)-3-hexen-1-ol, (E)-4-hexen-1-ol, 5-hexen-1-ol, 1-hexen-3-ol, 5-hexyn-1-ol, hydrogen peroxide solution, lithium diisopropylamide, magnesium sulfate, n-octan-1-ol, 1-octen-3-one, n-pentan-1-ol, 4-penten-1-ol, petroleum ether, phenoxyacetic acid, propionic acid, sodium bicarbonate, sodium thiosulfate pentahydrate, tetrahydrofuran, triethyl orthoacetate, trimethylamine, and vinylmagnesium bromide solution were purchased from Sigma-Aldrich (Steinheim, Germany). The educts 1-hepten-3-ol, 1-hexen-3-one, and 7-octen-1-ol were purchased from abcr (Karlsruhe, Germany) and chloroform, sodium hydroxide, and sulphuric acid from Carl Roth (Karlsruhe, Germany). Dichloromethane, ethyl acetate, n-hexyl acrylate, methanol, 1-nonen-3-one, n-propyl acrylate, silica gel (Normasil 60, 40–63 µm), and sodium chloride were purchased from VWR International GmbH (Darmstadt, Germany). All reactants were at least of reagent grade.

2-Bromopropionic acid,
acetone, acetonitrile,
anhydrous ethyl ether, hexanes, hydrochloric acid (37%), anhydrous
magnesium sulfate, methanol, methylene chloride (DCM), potassium hydroxide,
sodium bicarbonate, sodium chloride, sodium hydroxide, HPLC-grade
tetrahydrofuran (THF), toluene, and N,N′-dicyclohexylcarbodiimide (≥99%) (DCC) were
purchased from Fisher Scientific. Ethanol was purchased from Decon
Laboratories. 1,4-Dioxane, 2-bromoethanol (95%), 4-(dimethylamino)pyridine
(≥99%) (DMAP), benzyl alcohol, n-butyl acrylate
(nBA), copper(I) bromide (99.999%), copper(I) chloride (>99.995%),
ethyl acetate (99.5%), methyl methacrylate (MMA), and N,N,N′,N″,N″-pentamethyldiethylenetriamine
(PMDETA) were purchased from Sigma-Aldrich. 2,3,3-Trimethylindolenine
(>97.0+%) and 3-chloromethyl-5-nitrosalicylaldehyde
were purchased from TCI Chemicals. Phosphotungstic acid was purchased
from Electron Microscopy Sciences. Milli-Q water (18.2 MΩ·cm)
was obtained from a Synergy water purification system (MilliporeSigma).
The monomers (nBA and MMA) were filtered through activated neutral
alumina immediately before use to remove inhibitor. The initiator,
SPBr₂, was synthesized following the literature procedure
(see the Supporting Information). All other
reagents were used as received unless otherwise noted.

Styrene (S, ≥99%), n-butyl acrylate (BA, ≥99%), 4-(dimethylamino)pyridine (DMAP), N,N′-dicyclohexylcarbodiimide (DCC), and tert-butyl hydroperoxide (70 wt % in water) were purchased
from Sigma-Aldrich. Methacrylate- and alcohol-functionalized azobenzene
(98.5% and 97.3%, respectively) were obtained from Synthon. The ASR
solution, ammonium persulfate (APS), and sodium erythorbate were used
as received from BASF. The alkali-soluble resin (ASR) was synthesized
by copolymerization of acrylic acid with Styrene, α-methylStyrene,
and optionally a low percentage of an acrylic aliphatic ester. The
weight-average molecular weight of the ASR is typically <10 kDa.
A clear yellowish ASR solution with 30% solids and a pH of 7–8
was prepared by dissolving ASR (300 g) in water (620 g) via the addition
of a 25% aqueous ammonium hydroxide solution (80 g). All chemicals
were used as supplied. Deionized water was used throughout this research.
The glass plates (3 cm × 3 cm) were cleaned with tissue paper
with acetone and dried under an air flow. The paperboard substrate
was kindly provided by Storaenso, type “Ensocard”. This
is an uncoated bleached board having a thickness of 215 μm (170
g/m²).

2,3,4,5,6-Pentafluorobenzyl bromide (Fluorochem,
99%) and acrylic acid (Sigma-Aldrich, 99%) were used as received.
Acetone (Sigma-Aldrich, ≥99%) was stored with molecular sieves
(3 Å, Sigma-Aldrich) to make it anhydrous prior to use. Diethyl
ether (≥99.8%), n-butyl acrylate (BA, ≥99%),
and methanol (≥99.9%) were purchased from Sigma-Aldrich and
used as received. Potassium carbonate (anhydrous, ≥99%), sodium
bicarbonate (≥99.7%), anhydrous magnesium sulfate, acetonitrile
(≥99.8%), chloroform (≥99.8%), and tetrahydrofuran (THF,
chromatography GPC grade) were obtained from Fisher Scientific. Sodium
azide (99%) and N,N-dimethylformamide
(DMF, dried over molecular sieves, 99.8%) were purchased from Acros
Organics and used as received. chloroform-D (CDCl₃, 99.8%,
+0.05% v/v TMS) was obtained from Cambridge Isotope Laboratories,
Inc. Azobisisobutyronitrile (AIBN, Sigma-Aldrich, 98%) was recrystallized
from methanol and dried at room temperature prior to storage in a
freezer. 4-Chloro-7-nitro-2,1,3-benzoxadiazole (NBD chloride, 98%)
and piperazine (99%) were purchased from Sigma-Aldrich and Fluorochem,
respectively. Two commercial polyacrylate copolymer PSAs (referred
to hereafter as P1 and P2), which were used as a benchmark in this
work, were provided by Synthomer plc.

The monomer n-butyl acrylate (BA, ≥99%, stabilized with 10–60 ppm monomethyl ether hydroquinone, Sigma Aldrich, Darmstadt, Germany) was distilled at 5 mbar to remove the inhibitor. The solvents 1,4 dioxane (99.8%, water free, Sigma Aldrich), 2-octanone (≥98%, Sigma Aldrich), toluene (99.9%, Sigma Aldrich, Darmstadt, Germany), xylene (technical mixture of isomers, VWR Elements) and mesitylene (99%, Acros Organics, Schwerte, Germany) were used as received. Tetrahydrofuran (THF, 99%, Grüssing, Filsum, Germany) was employed as eluent for size-exclusion chromatography (SEC). Hydroquinone (99%, Riedel) dissolved in methanol (98.5%, CG Chemikalien, Hannover, Germany) was used to stop the polymerization.

Methyl methacrylate (MMA), n-butyl acrylate (nBA), chloroform, methyl ethyl ketone (MEK), and initiator azobisisobutyronitrile (AIBN) were purchased from Sigma-Aldrich and used as received. Hexane and tetrahydrofuran (THF) were purchased from Thermo Fisher-Scientific and used as received. chloroform-D was purchased from ACROS Organics.