1070-4272/04/7705-0817C2004 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 77, No. 5, 2004, pp. 817!819. Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 5,
2004, pp. 822!824.
Original Russian Text Copyright + 2004 by Klimets, Grinyuk, Nareiko, Skakovskii, Tychinskaya, Krul’.
AND POLYMERIC MATERIALS
Aqueous Adhesives Based on Dextrin-Containing
T. G. Klimets, E. V. Grinyuk, E. I. Nareiko, E. D. Skakovskii,
L. Yu. Tychinskaya, and L. P. Krul’
Research Institute of Physicochemical Problems, Belarussian State University, Minsk, Belarus
Received January 22, 2004
Abstract-Rheological and adhesion characteristics of water-soluble adhesive composites based on copolymer
of acrylamide with sodium acrylate and corn dextrin were studied. The optimum composition of these com-
posites in their use as label adhesives was determined.
High-quality label adhesives should have the fol-
lowing characteristics: high reliability of the adhesive
joint in the initial stage of drying, short time of set-
ting, and, desirably, pseudo-plastic character of
It is well known that aqueous saline solutions of
copolymers of acrylamide with sodium acrylate
(CASA) are used as label adhesives . However,
these adhesives have poorly pronounced pseudo-plas-
ticity and fairly prolonged time of setting; they en-
sure low reliability of the adhesive joint in the first
minutes. These characteristics can be improved by in-
creasing concentration of polymer in the solution.
However, increase in the concentration of CASA
results in significant increase in the solution viscosity,
which hampers its use as adhesive .
Another approach to improvement of character-
istics of adhesives based on CASA is, apparently,
development of composites with other polymers.
Here we studied the possibility of using corn dex-
trin (CD) for improvement of adhesion and rheologi-
cal characteristics of glues based on CASA.
As the initial materials we used aqueous3saline
solution of CASA with the concentration of 27.5%
and shear viscosity of 35 Pa s, and also acidic corn
dextrin (high grade, pale yellow), GOST (State Stan-
dard) 6034374. Copolymers of acrylamide with sodi-
um acrylate were produced by base hydrolysis of Ni-
tron D polyacrylonitrile fiber according to TU RB
(Technical Specification of Belarus Republic)
00280 198.026396. The resulting hydrolyzate was
neutralized with acetic acid.
The viscosity of the resulting solutions was deter-
mined on a Rheotest 2 rotary viscometer with a cylin-
der3cylinder working unit at 20+0.1oC .
To determine adhesion characteristics of the hy-
drolyzate solutions in the system glass3adhesive3
paper, we used an RMU-0.05-1 tearing machine with
the limits of load measurements of (0310)+0.02 kgf
and velocity of the guide rod of the machine of up to
100 mm min
The content of the dry substance was determined
gravimetrically by drying in a thermostat at 80oCto
constant weight. The polymer concentration was deter-
mined by subtraction of the salt concentration from
the content of dry substance. The salt content was
evaluated by the formula
is the concentration of salt in the neutral-
ized hydrolyzate (%), n
is the amount of acetic
acid consumed for neutralization (mole), and m
weight of the neutralized hydrolyzate (g).
C NMR spectra were recorded on a Tesla
BS-587A spectrometer operating at 20 MHz. We used
10% solutions of copolymers in D
O placed into
standard ampules (10 ml). The spectra were recorded
without Overhauser effect with pulse delay exceeding
, where T
is the spin3lattice relaxation time of
the most slowly relaxing nuclei. The signals were as-
signed by the DEPT procedure with the use of model
compounds . The chemical shifts were measured
using the signal of methyl group of acetone-d
to the reaction mixture as a reference (d 30.2 ppm).
The composites of aqueous saline solution of
CASA with CD were prepared at room temperature
and at 65+5oC.