Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 5, pp. 794−798.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © T.N. Spirina, N.N. Saprykina, O.A. Andreeva, E.M. Kulikova, Yu.N. Sazanov, S.M. Krutov, V.E. Yudin, 2012, published in Zhurnal
Prikladnoi Khimii, 2012, Vol. 85, No. 5, pp. 794−798.
AND POLYMERIC MATERIALS
Morphology of Modiﬁ ed Hydrolysis Lignin
T. N. Spirina
, N. N. Saprykina
, O. A. Andreeva
, E. M. Kulikova
Yu. N. Sazanov
, S. M. Krutov
, and V. E. Yudin
Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia
St. Petersburg State Academy of Forestry Engineering, St. Petersburg, Russia
Received March 6, 2012
Abstract—The morphology of hydrolysis lignin was studied. The effect of dimethyl sulfoxide, temperature, and
activating additives on the surface characteristics of lignin was examined.
Utilization of hydrolysis lignin (HLG) still remains
an urgent problem, because the possibility of using this
macromolecular compound for preparing composite
materials (CMs) is of much interest. The mechanism of
thermochemical transformations of hydrolysis lignins,
based on competing reactions of low-temperature con-
densation and thermal degradation, was suggested [1–4].
Mixed solutions of lignin with polyacrylonitrile were
studied, and it was suggested that these polymers form
In this study we examined the morphological structure
of modiﬁ ed HLG and the effect of temperature, solvents,
and activator on the formation of the lignin precursor for
obtaining a composite material.
Heat treatment of HLG was performed by the proce-
dure described in . Samples after the heat treatment
were ﬁ ltered off, washed with water and alcohol, and
dried in a vacuum oven at 50°С.
Experiments were performed with hydrolysis lignin
from the Kirov Hydrolysis Plant, pulverized to microm-
eter size. Dimethyl sulfoxide (DMSO) used as solvent
(IMP grade) and sodium hydroxide (analytically pure
grade) were purchased from Vekton Private Joint-Stock
Electron-microscopic studies of the sample morphol-
ogy were performed with a SUPRA-SSVP scanning
electron microscope (Zeiss, Germany). Preliminarily
the samples were coated with gold by cathode sputter-
ing using a Poloron installation (the United Kingdom).
Elemental analysis was performed with an MX energy-
dispersive spectrometer incorporated in the microscope
(INCA Oxford, the United Kingdom).
The IR Fourier spectra of the powdered samples were
taken with a Bruker Vertex 70 spectrometer from KBr
pellets. The particles were dispersed with a UZDN-1
ultrasonic installation at a frequency of 35 kHz.
Thermal analysis was performed with a C derivato-
graph (MOM, Hungary) in an inert atmosphere at a heat-
ing rate of 10 deg min
. The sample weight was varied
depending on the aims of the experiment. The samples
were powders dried to constant weight under reduced
pressure at 50°С.
The initial HLG is a ﬁ nely dispersed powder. The par-
ticle size varies within 154–1950 nm, with the particles
of size 308 nm prevailing (Figs. 1a, 1b). At ×150000
magniﬁ cation (Fig. 1c), one can see crystals assignable
to formations of the low-molecular-weight HLG fraction.
It is known that lignin contains a noticeable amount
of water adsorbed on the surface and in pores of the
sample . To remove moisture which can affect further
modiﬁ cation of HLG, the sample was heat-treated in