ISSN 1070-4272, Russian Journal of Applied Chemistry, 2016, Vol. 89, No. 8, pp. 1360−1364. © Pleiades Publishing, Ltd., 2016.
The text was submitted by the authors in English.
Polyol is an important polymer that has wide
application such as in detergent, emulsiﬁ er, dispersant,
and antistatic agent. One of its most important applications
is the preparation of polyurethane (PU), which has wide
application in coatings, packing, automobile, elastomers,
aviation, sealants, and aircraft manufacturing [1–3].
However, most of polyol is produced from petroleum,
and the price heavily depends upon the oil markets
in the world.
Also, in view of petroleum reserves and
environmental issues, it should search alternative
resources for producing polyol. Cellulose, semi-cellulose,
and lignin, as three major components of biomass, have
lots of hydroxyl groups. So, biopolyols with sufﬁ cient
amount of hydroxyl groups may be produced from various
biomass feedstocks. The subject has been paid more
and more attentions. Untill now, a variety of biomass
considering as raw material has been studied for the
production of biopolyols [4–10].
Generally polyols produced from biomass possess
promising properties for the production of PU and the
resulting PU shows properties comparable to that based
on petroleum [11–13]. Rice straw, as agricultural wastes,
is an abundant, renewable, and cheap resource. Most of
them are not fully utilized such as by direct combustion
without any disposal, that pollutes the environment and
wastes the biomass resource. Thus, converting rice straw
into polyols by liquefaction may produce great social,
economic, and environmental beneﬁ ts, therefore, it is
important in theory and valuable in practice to research
in this respect .
In the study, biopolyols prepared by the liquefaction of
rice straw were investigated under the mild condition. The
effects of different liquefaction conditions were discussed.
The characteristic of biopolyols was also tested.
Materials. Rice straw used in the study was collected
from the farm at Xuzhou city, Jiangsu, China. It was
washed with de-ionized water, air-dryed, and then ground
to pass through 40 mesh sieve. All the raw materials were
dried in an oven at 105°C for 24 h before liquefaction,
and then stored in a desiccator at room temperature
All chemicals used in the experiment are of analytical
grade, obtained from the commercial source, and used
without further puriﬁ cation.
Preparation and Characterization of Biopolyol
via Liquefaction of Rice Straw
Guizhen Gong and Xiucheng Zou
School of Chemical Engineering, Xuzhou Institute of Technology, Xuzhou 221111, China
Received July 13, 2016
Abstract—Biopolyols were prepared by the liquefaction of rice straw under the mild condition. The optimum
liquefaction effect was obtained at 5 : 1 volume ratio of PEG400 to DEG, 4 : 1 liquid–solid ratio, H
2.5 h, and reaction temperature120°C. Products were characterized by FTIR and gel permeation chromatograms
(GPC) measurements. The hydroxyl value and weight-average molecular weight of the biopolyol produced based
on the above optimal conditions were 260 mg KOH/g polyol and 420 g mol
, respectively. Biopolyol obtained
is suitable for the preparation of rigid polyurethane foam. This study has certain signiﬁ cance for the high added
value use of rice straw and reducing the production cost and improvement biodegradability of polyurethane foams.