Environmentally-Friendly Acrylates-Based Polymer Latices - Advanced Materials for Agriculture, Food and Environmental Safety - page 166

crosslinked latex. h is was explained by the fact that intramolecular chain
transfer to the polymer was favored by low monomer concentrations.
Polymers of EGDM, diethylene glycol dimethacrylate, triethylene glycol
dimethacrylate and tetraethylene glycol dimethacrylate were prepared by
photoinitiated polymerization in the presence of 2,2-dimethoxy-2-phenyl-
acetophenone at 27

C by Bowman and Peppas [150]. h ese systems were used
predominantly as crosslinking agents during the copolymerization of hydro-
philic monomers for the production of important biomedical polymers [151].
A series of poly(propylene glycol-diacrylate) (PPGDA) having molecu-
lar weight in the range of 300-3000 were synthesized by Malucelli et al.
[152]. h ey studied the preparation and characterization of PPGDA oligo-
mers. Moreover, mixtures of the PPGDA oligomers with a typical epoxy
acrylic resin were examined in order to evaluate the l exibility properties
of these oligomers introduced in a rigid network.
Water-soluble polymers [153] were synthesized by free radical copol-
ymerization of MMA, α -methyl- ω -methacroyl-poly(ethylene glycol) and
2-HEMA. h e methacrylate containing hydrogel precursors were obtained
by the reaction of free hydroxyl groups of HEMA in the polymer with
methacrylic anhydride in the presence of catalyst. γ -Irradiation was used
as an elegant method for crosslinking and simultaneous sterilization.
Formulations for waterborne printing inks based on self-crosslinking
ketone functional acrylate emulsions were prepared by de Krom et al.
[154-156]. Results of measurements of gloss, drying, adhesion and various
resistance properties of the coatings on nonabsorbent substrates have been
discussed. h ese inks dried very rapidly and have good adhesion, resis-
tance to solvents and water, with high gloss.
A self-curing thermosetting water-dispersed polymer consisting of sty-
rene, ethyl acrylate, methacrylic acid, N-isobutoxymethyl acrylamide and
methacryloyloxyethyl phosphate has been used as an interior coating for
cans by Martino [157]. It has been claimed that a coating consisting of an
acrylic polymer latex and aminoplast curing agent has good adhesion and
gloss, and is resistant to water, solvent and chemicals. h e baking schedule
has been reported to be 26ºC for 42 seconds by Kuhn et al. [158].
Novel self-crosslinkable grat copolymers with a pendant blocked iso-
cyanate in the i rst segment, and a hydroxyl group in the second segment,
were developed by Yukawa et al. [159]. M-isopropenyl-α, α-dimethylbenzyl
isocyanate were copolymerized with butyl acrylate, 2-hydroxyethyl acry-
late to form the grat copolymer, by incorporating neutralizable function-
alities such as carboxyl or tertiary amino groups to the second segment
of the grat copolymer, to prepare self-dispersible (self-stabilized) aqueous
coating vehicles.

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