Preparação de Resinas de Poliuretana à Base de Óleo de Mamona e Dietanolamina e sua Aplicação em Circuitos Eletroeletrônicos

Abstract

Resumo: O óleo de mamona é um óleo vegetal que permite várias reações em seus grupos funcionais hidroxila. O ácido ricinoleico (ácido 12-hidroxioleico) compõe cerca de 90% dos ácidos graxos presentes, enquanto os outros 10% são não hidroxilados. Este trabalho teve como objetivo obter polióis a partir de misturas do óleo de mamona tipo I (OM) com dietanolamina (DEA), visando elevar o grau de reticulação dos produtos finais, para uso em circuitos eletroeletrônicos. A intenção de se introduzir a dietanolamina nas formulações de resina de poliuretana advém das dificuldades apresentadas por empresas do ramo na aquisição da trietanolamina, que atualmente se encontra sob controle de órgãos federais. Análises químicas e espectroscópicas evidenciaram a obtenção de polióis com índice de hidroxila entre 230 e 280 mgKOH/g. A cinética da reação de poliadição entre os polióis resultantes e o isocianato de isoforona (IPDI) foi acompanhada pelas mudanças nas propriedades reológicas do meio, a 60 °C. As poliuretanas apresentaram propriedades compatíveis com as dos produtos atualmente disponíveis no mercado, obtidos com trietanolamina (TEA). Palavras-chave: Óleo de mamona, dietanolamina, poliuretana, propriedades reológicas, propriedades elétricas, dureza. Preparation of Polyurethane Resins Based on Castor Oil and Diethanolamine and their Application in Electronic CircuitsAbstract: Castor oil (CO) is a vegetable oil that allows for multiple reactions in their hydroxyl functional groups. Ricinoleic acid (12-hidroxioleic acid) comprises about 90% of the fatty acids present while the remaining 10% are not hydroxylated. The aim of the present work was to obtain polyols from castor oil (CO) and diethanolamine (DEA), to improve the crosslinking degree of final products to be used in electronic circuits. The use of diethanolamine instead of triethanolamine in the polyurethane resin formulation is of special interest of companies, due to the difficulties in acquiring triethanolamine, which is controlled by the Brazilian Army. Chemical and NMR characterization showed that the polyol obtained had a hydroxyl number between 230 and 280 mgKOH/g. The kinetics of the polyaddition reaction from polyols and isophoronediisocyanate (IPDI) was evaluated employing rheological assays at 60 °C. The polyurethane based on DEA had compatible properties with the commercial products obtained from triethanolamine (TEA).

Surface and micromechanical analysis of polyurethane plates with hydroxyapatite for bone structure

“…Such results corroborate those by Sathiskumar and Madras [22] . A stretch band at 1700 cm -1 corresponding to the carbonyl functional group (C=O), a CO-O bond (urethane) corresponding to the band at 1250 cm -1 , and a hydroxyapatite phosphate radical peaking at 1150 cm -1 are compatible with the molecular structure of a castor oil-based PU and HA, corroborating the results by Cardoso and Balaban [21] .…”

“…Spectroscopy in the infrared region was used because it is the most suitable technique for the qualitative determination of the products formed, as it is based on the vibrational energies of the bonds in the sample and one of the most important techniques for identifying and/or determining structural characteristics of polymers, especially regarding the functional groups and bonds in the sample [21] . The transmittance band in the 3315 cm -1 region is compatible with the presence of N-H bonds of urethanes and stretching in the 2939 cm -1 and 2852 cm -1 regions related to asymmetric and symmetric CH 3 stretching, respectively.…”

Polyurethane derived from castor oil monoacylglyceride (Ricinus communis) for bone defects reconstruction: characterization and in vivo testing

“…However, many properties and characteristics are required for medical devices and tissue engineering, such as good mechanical performance, a 3D structure, and a degradation rate compatible with the application. Various methods can circumvent these barriers, from the combination of chemical modification techniques, adapting the device's properties, suitable formats, or variations in the polyol-isocyanate composition [6][7][8][9]. Polymers are macromolecules with high molar mass, in the order of 103-106 g/mol, formed by the repetition of chemical units called "mere".…”

“…The structure of urethane results from a chemical reaction between an isocyanate group and a hydroxyl group. The synthesis of polyurethane results from the reaction between a compound with two or more isocyanates and polyfunctional alcohol (hydroxylated low molecular weight polymer or polyol) [7][8][9].…”