%0 Journal Article
%T Preparation and Structural Properties of Free Films from Rapeseed Oil-Based Rigid Polyurethane-Montmorillonite Nanocomposites
%A Sergey Gaidukov
%A Ugis Cabulis
%A Karina Gromilova
%A Velta Tupureina
%A Agnese Grigalovica
%J International Journal of Polymer Science
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/834595
%X The preparation of free standing films of biobased rigid polyurethanes (PU) from rapeseed oil (RO) and diethanolamine (DEA) polyol and its modification with organomontmorillonite (OMMT) nanoparticles are described. Heat enthalpy of the interaction during in situ mixing of RO/DEA polyol and OMMT is measured in isothermal profile. The Fourier transform infrared spectral analysis (FTIR-ATR) is used to determine the urethane group concentration and hydrogen bonds formation in PU and PU/OMMT nanocomposites. X-ray diffraction shows the formation of intercalated and exfoliated structures of OMMT. The glass-transition temperature is used to demonstrate the formation for the intercalated and exfoliated nanocomposites of an interphase with a possible compact structure and the altered polymer chain mobility. The prepared PU/OMMT nanocomposites are also characterized by the enhanced thermal degradation characteristics upon heating in air atmosphere. 1. Introduction During the last decades, bioderived or biobased polymers from different initial raw materials have been widely produced and characterized [1, 2]. The main goal of such investigations is to replace the traditional sources of raw materials¡ªderivatives of gas and oil fossils, that is, monomers, oligomers, and resins, with the biologically based or biologically derived ones [1¨C4]. For example, vegetable oils [4], bacteria and microorganism source products or byproducts [5], and wood chemical technology products (cellulose, lignin, etc.) [6] can be utilized to prepare plastics. Such polymeric materials are called biobased polymers or green polymers [7]. The strategy of such a substitution is quite obvious¡ªthe ecological reasons, as well as the legislation and high costs of petrochemical raw materials [8]. This is especially important due to the expected reduction in fossil oil and gas production. New ways of producing traditional plastics from natural vegetable oils and plant and wood derivatives are sought for. For example, biobased polyethylene terephthalate [9], polycarbonate [10], polyethylene [11], polyamide [12], epoxide oligomers [13], and polyurethanes [14] can be produced. Some of biobased polymers, for example, polyhydroxyalkanoates [15], polylactides [16], and starch [17] are fully biodegradable. The high versatility of the polyurethane raw materials allows manufacturing a large variety of products with different structures and properties. Generally, polyurethane (PU) is fabricated by a polycondensation reaction of low-molecular-weight components: polyols and isocyanates [14]. Recently, market and
%U http://www.hindawi.com/journals/ijps/2013/834595/