Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 10, pp. 1805−1808.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © I.P. Dobrovol’skaya, P.V. Popryadukhin, V.E. Yudin, K. Balik, Z. Weishauptova, M. Zaloudkova, 2011, published in Zhurnal Prikladnoi
Khimii, 2011, Vol. 84, No. 10, pp. 1713−1716.
AND POLYMERIC MATERIALS
Nanoﬁ bers Based on an Aliphatic Copolyamide,
Prepared by Electroforming
. P. Dobrovol’skaya
, P. V. Popryadukhin
, V. E. Yudin
, K. Balik
, and M. Zaloudkova
Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia
Institute of Rock Structure and Mechanics ASCR, Prague, Czech Republic
Received February 25, 2011
Abstract—The rheological properties and stability of solutions of poly-ε-caprolactam–polyhexamethyleneadipamide
copolymer in an alcohol–water solvent were studied. The properties of ﬁ bers prepared from the copolymer solution
by electroforming were examined.
Electroforming allows preparation of polymer ﬁ bers
from 50 to 4500 nm in diameter. The solution or melt
of a polymer undergoes polarization in a high-intensity
electric ﬁ eld with the formation of microjets, which are
deposited in the form of nanoﬁ bers [1, 2]. This procedure
is used for preparing nanofibers of polyethylene,
polypropylene, polyvinyl alcohol, polyethylene
oxide, polyvinylpyrrolidone, polyamides, polymethyl
methacrylate, polylactide, cellulose derivatives, and other
polymers. Materials based on nanoﬁ bers are characterized
by low density, high porosity, and permeability to water
and gases [2–4].
Preparation of fibers by electroforming from
a solution of an aliphatic polyamide is described in
a patent . In this process, concentrated (88%) formic
acid was used as solvent, which considerably complicates
the electroforming process and is environmentally
Aliphatic copolyamides are of interest for preparing
nanoﬁ bers by electroforming, because they are soluble
in alcohol–water mixtures. These polymers are used for
preparing porous ﬁ lm materials by coagulation of the
polymer in aqueous or aqueous-alcoholic precipitation
It is known that the poly-ε-caprolactam–
polyhexamethyleneadipamide copolymer (CPA) exhibits
the best ﬁ lm- and ﬁ ber-forming properties . In addition,
it is bioinert and contains no residual solvent or other
harmful impurities, which allows this CPA to be used
for preparing medical materials and matrices for cell
technologies. The solvent is alcohol–water mixture,
which makes the forming process environmentally safe.
Materials based on this polymer preserve the service
characteristics in aqueous media for a long time. They are
used as ﬁ ltration materials for ﬁ ne puriﬁ cation of liquid
and gaseous media .
Data on preparation of nanoﬁ bers from aliphatic
copolyamides by electroforming are lacking. Data on
the rheological properties of aliphatic copolyamides
in alcohol–water solvents and on correlation of these
properties with the ﬁ ber structure are insufﬁ cient.
In this study we examined the rheological properties
of CPA solutions in an alcohol–water solvent, the phase
state of these solutions, and the structure of nanoﬁ bers
prepared by electroforming.
The investigation objects were solutions of poly-ε-
(PA 6/66, Anid Limited Liability Company) in alcohol–
water solvents. The concentration of CPA solutions