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EN
This paper investigates the reinforcement of rigid polyurethane foams with microcrystalline cellulose to improve their mechanical and thermal properties. In this work, microcrystalline cellulose was added to polyol and was dispersed using two methods: calendering and ultrasounds. As a result of the study, it was found that the addition of micro cellulose to the polyol mixture used for the synthesis of polyurethane foam changes the properties of the final product. A crucial aspect is how it is added to the mixture. When adding microcrystalline cellulose particles, better results were obtained for particles dispersed using ultrasound. The most beneficial changes were obtained for the sample with 2php cellulose. The most significant reduction in average pore size was shown, which has a beneficial effect on the insulating properties of polyurethane foam. In addition, an increase in mechanical properties was also noted. Both properties are highly desirable in many applications.
EN
A poly(hydroxybutyl citrate) p(HBC) was obtained. The product compound produced in the solution during esterification, was added to rigid polyurethane-polyisocyanurate foams (PUR-PIR). The amount of petrochemical polyol in the foams was decreased in favor of the p(HBC) from 0.1 to 0.5 equivalent. The foams were foamed in two ways: with distilled water (W foams) and with Solkane 365/227 (S foams). The examination results of both foam series were compared. They showed that the foams foamed with water have higher softening temperature than the foams foamed with solkane. The retention values for both foam series are around 91–95%, and water absorption in the range of 0.7–3.2%. The anisotropy coefficient did not exceed 1.08 (the lowest value being 1.01).
EN
A literature review and own investigations have been a base for presenting various methods of the synthesis of bio-polyols from renewable raw materials as well as their potential applications in the formulations of flexible and rigid polyurethane foams (Table 1). A characteristics of selected bio-polyols (Table 2) and their effect on foaming process of different polyurethane compositions are shown (Fig. 1, Table 3). Examples of the influence of selected bio-polyols on cell structures and physical and mechanical properties of both flexible (Fig. 2) and rigid (Table 4) foams are also presented.
PL
Na podstawie przeglądu literatury i badań własnych omówiono różne metody wytwarzania bio-polioli z surowców odnawialnych oraz możliwości ich zastosowania w syntezie elastycznych isztywnych pianek poliuretanowych (tabela 1). Zaprezentowano charakterystykę wybranych ­bio-polioli (tabela 2) oraz ich wpływ na przebieg procesu spieniania różnych kompozycji poliuretanowych (rys.1, tabela 3). Podano przykłady wpływu wybranych bio-polioli na strukturę komórkową i właściwości ­fizyczne i mechaniczne modyfikowanych pianek elastycznych (rys. 2) i sztywnych (tabela 4).
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