1070-4272/05/7805-0839C2005 Pleiades Publishing, Inc.
Russian Journal of Applied Chemistry, Vol. 78, No. 5, 2005, pp. 839!842. Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 5,
2005, pp. 856!859.
Original Russian Text Copyright + 2005 by Krul’, Ivanova, Yakimtsova, Grinyuk.
AND POLYMERIC MATERIALS
Water-Soluble Polymers of Acrylamide as Labeling Adhesives
L. P. Krul’, T. A. Ivanova, L. B. Yakimtsova, and E. V. Grinyuk
Belarussian State University, Minsk, Belarus
Received January 19, 2005
Abstract-The adhesive and rheological properties of high- and low-molecular-weight polyacrylamides and
the products of their partial hydrolysis were studied. The suitability of the hydrolyzates of high-molecular-
weight polyacrylamide as labeling adhesives in the glass3paper system was elucidated.
A major proportion of the labeling adhesives used
for gluing paper labels to glass containers is accounted
for by aqueous polymeric adhesives . An important
place among them is occupied by water-soluble co-
polymers of acrylamide (AA) with sodium acrylate,
prepared by base hydrolysis of waste from polyacrylo-
nitrile fiber production [2, 3]. However, the molar
ratio of the acrylamide to acrylate units in the macro-
molecule of such copolymers, capable of modifying
their adhesive properties, can be varied within very
narrow range only (from 0.25 : 0.75 to 0 : 1) .
The reason is that a solid fiber can pass into solution
only at high concentrations of the hydrolyzing agent.
At the same time, hydrolysis of water-soluble poly-
acrylamide (PAA) allows preparation of a copolymer
with the desired ratio of the acrylamide to acrylate
units . This makes possible preparation of labeling
adhesives on the basis of partially hydrolyzed PAA
(HPAA) with easily controllable adhesive properties.
Water-soluble polymers of AA, including HPAA
along with PAA proper, are capable of gluing together
polar substrates, in particular, paper and glass .
However, the properties making these polymers suit-
able as labeling adhesives were studied to a lesser
extent than the properties of hydrolyzates of poly-
acrylonitrile fibers .
In this study, we examined the adhesive properties
of PAA and HPAA with various molecular weights,
hydrolyzed to various degrees, in the glass3paper
For synthesis of PAA we used AA available from
REANAL (Hungary) with 98.7% main substance. The
synthesis was run in 7% aqueous solutions of the
monomer using the ammonium peroxodisulfate3sodi-
um sulfite redox initiating system. The molecular
weight (MW) of PAA was controlled by varying the
total concentration of the components of the redox
system and the component ratio in it. Base hydrolysis
of PAA was conducted in 7% aqueous solutions of
the polymer at their boiling point for 3 h at various
ratios of the amounts of the polymer and NaOH. For
procedures of the PAA synthesis and base hydrolysis
of the polymer synthesized, see .
The viscosity-average MW was determined vis-
cometrically. The specific viscosity was measured
in a suspended-level Ubbelohde capillary viscometer
with a capillary diameter of 0.86 mm at 25oC.
The adhesive properties of the solutions in the
glass3adhesive3paper system were determined by the
known procedure [12, 13] on an RMU-0.05-1 tensile-
testing machine. After the paper was glued to glass,
the sample was maintained at room temperature,
whereupon the shear strength of the glue joint was
determined. The time of keeping of the sample after
gluing was 1, 2, 3, 5, 10, and 20 min. Simultaneously
with the strength of the glue joint we determined
the character of its failure.
The dynamic viscosity of the solutions was deter-
mined at 20+0.1 oC on a Rheotest 2 rotary viscometer
with the cylinder3cylinder working unit.
The quality of polymeric adhesives for the glass3
paper system is determined, above all, by the char-
acter of failure of the glue joint. It is known that con-
ventional labeling adhesives finding wide commercial
application should provide a paper3glass joint so
strong that, at attempted break of the glue joint after
drying of the adhesive, the failure occurs across the
paper texture . Also, it is necessary that, before
drying of the adhesive, the label will not come off
from the glass surface, which is achieved through