1070-4272/01/7501-0106$27.00C2002 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 75, No. 1, 2002, pp. 106 !111. Translated from Zhurnal Prikladnoi Khimii, Vol. 75, No. 1,
2002, pp. 107!112.
Original Russian Text Copyright + 2002 by Mikhailova, Nazarova, Khizhnyak, Anan’eva, Pakhomov.
AND POLYMERIC MATERIALS
Structure and Properties of Filled Film Materials
Based on Ultra-High-Molecular-Weight Polyethylene
Yu. N. Mikhailova, E. V. Nazarova, S. D. Khizhnyak,
T. A. Anan’eva, and P. M. Pakhomov
Tver State University, Tver, Russia
St. Petersburg State University of Technology and Design, St. Peterburg, Russia
Received July 10, 2001
Abstract-The pore structure of filled films of ultra-high-molecular-weight polyethylene prepared by the
gel process was studied by IR spectroscopy and optical microscopy. The moisture and water absorption and
the maximal sorption capacity of the material were determined gravimetrically and examined in relation to
the degree of filling of films with peat and to the molecular weight of the polymer.
Considerable researchers’ efforts in the polymer
technology are aimed at development and promotion
of new materials with valuable properties, in particu-
lar, of porous materials. The most widely used proce-
dure for preparing porous materials involves conden-
sation cross-linking based on spontaneous physico-
chemical processes in polymer solutions [1, 2]. Poly-
mers can also be processed into porous materials by
extrusion of a polymer melt at a high flow velocity,
followed by annealing of samples crystallized at room
temperature, uniaxial drawing of the annealed sam-
ples, and thermal fixation .
One of promising processes in polymer technology
is the sol3gel process. Interest in this process arose
in mid-1970s and was due to the possibility of pre-
paring ultra-high-strength fibers from solutions and
gels of flexible-chain polymers [4, 5]. Researchers’
efforts  were aimed at production of highly
porous polymeric materials by the sol3gel process and
at their structural study. In this connection, structural
study of polymeric xerogels (dry gel without solvent),
which are highly porous materials, becomes topical.
It is also interesting to examine the effect of fillers on
the gelation process and structure of the resulting
filled porous materials, which can be used as sorbents
for petroleum and other products.
The goal of this study was to reveal the effect of
a disperse filler (peat) on the properties and structure
of filled film materials prepared from ultra-high-
molecular-weight polyethylene (UHMWPE) by the
1.5 0 10
and 4.0 0 10
) was pur-
chased from Hoechst. Films were prepared from a
2 wt % solution of UHMWPE in solid paraffin C
. As compared to traditionally used UHMWPE
solvents such as xylene or decalin, paraffin is less
active. In such a solvent, conditions for interaction of
the polymer molecules and hence for formation of the
three-dimensional polymer network are more favor-
able. Less active solvents are also preferable in pro-
duction of filled materials .
As a UHMWPE filler we used peat. Peat was fine-
ly divided without preliminary drying and sieved
through a standard set of sieves; the fraction with the
grain size of 0.1530.25 mm was collected. Among
natural environmentally clean and cheap sorption-
active materials, peat occupies a particular place. In
the air-dry state it has low density, high porosity, high
hygroscopicity, and high moisture- and gas-absorption
power. In practice, peat sorbents are used as com-
pacted briquettes, granules, and finely divided peat.
However, studies showed that the impact of high tem-
peratures in the course of briquetting appreciably
impairs the sorption power of peat. Furthermore, in
water peat briquettes swell and break down. The direct
use of finely divided peat as a sorbent requires addi-
tional water treatment because of washing out of
humic acids in the course of service [10, 11].
Filled film materials were prepared as follows.
UHMWPE was dissolved in two stages. The first
stage (swelling) was performed at vigorous stirring