Castor Oil-based Polyurethane Resin Research Articles

Influence of Proportion Polyol/Pre-Polymer Castor-Oil Resin Components in Static Bending Properties of Particleboards Produced with <i>Pinus </i>sp<i>.</i>

The aim of this research is to evaluate the influence of castor-oil based polyurethane resin formulation (particularly proportion pre-polymer/polyol) in static bending properties of particleboards produced with Pinus sp. wood specie. Results related to modulus of rupture (MOR) and modulus of elasticity were determined. Four proportions polyol/pre-polymer were evaluated: 0.75:1; 1:1; 1:1.25; 1:1.5. Results showed improvement in MOR and MOE with increase of pre-polymer component. Proportion 1:1.25 (poliol: pre-polymer) was considered the most interesting once employs the least amount of the petroleum-derived component.

Oat hulls as addition to high density panels production

Wood-based panels have been widely used around the world in various segments of timber industry. Thus, alternative raw-materials have been systematically researched in order to reduce of wood demand in particleboard production. The aim of this work was to produce and evaluate particleboards of Eucalyptus grandis and oat hulls (Avena sativa), bonded under pressure with castor oil based polyurethane resin, in the proportion of 10% relative to the dry mass of the particles. The percentages of particles used per material were: Eucalyptus grandis 100, 85, 70 e 0% and oat hulls 0, 15, 30 e 100%, respectively. Physical-mechanical performance of the panels produced was evaluated based on standards ABNT NBR 14810:2006[1] and BS EN 312:2003[2]. By analysis of variance (ANOVA), the fraction of particles of Eucalyptus grandis was significant only in the modulus of rupture (MOR) in static bending. Panels produced with 100% oat hulls presented highest value of MOR.

Accelerated artificial aging of particleboards from residues of CCB treated Pinus sp. and castor oil resin

Tests simulating exposure to severe weather conditions have been relevant in seeking new applications for particleboard. This study aimed to produce particleboards with residues of CCB (chromium-copper-boron oxides) impregnated Pinus sp. and castor oil-based polyurethane resin, and to evaluate their performance before and after artificial accelerated aging. Panels were produced with different particle mass, resin content and pressing time, resulting eight treatments. Particles moisture and size distribution were determined, beyond panel physical and mechanical properties, according to NBR14810-3: 2006. After characterization, treatments B and G (small adhesive consumption and better mechanical performance, respectively) were chosen to artificial aging tests. Statistical results analysis showed best performances were achieved for waterproof aged samples, of both B and G treatments. As example, in treatment B, MOR and MOE values were 23 MPa and 2,297 MPa, samples before exposure; 26 MPa and 3,185 MPa, 32 MPa and 3,982 MPa for samples after exposure (non-sealed and sealed), respectively.

Medium density fiberboard manufactured with castor oil based polyurethane resin

Este trabalho objetivou avaliar a viabilidade da produção de painéis MDF fabricados com madeiras das espécies Pinus caribaea e Eucalyptus grandis e resinas poliuretanas mono e bicomponente derivadas do óleo de mamona, com base nas recomendações da norma europeia Euro MDF Board (EMB/IS-2:1995). Os painéis desenvolvidos com ambas as resinas foram confeccionados com parâmetros de fabricação distintos, em razão de testes preliminares desenvolvidos. Com exceção da absorção de água após 24 horas dos materiais fabricados com a madeira Eucalyptus grandis, todas as demais variáveis resposta atenderam aos requisitos do documento normativo europeu, evidenciando a potencialidade dos materiais fabricados. Entretanto, pelos valores significativamente superiores obtidos das propriedades mecânicas aliados aos excessivos valores da absorção de água, de maneira a contribuir com a possível fabricação dos painéis em escala industrial, novas pesquisas devem ser desenvolvidas, com o objetivo de testar novos valores para os parâmetros de fabricação, que possibilitem a redução dos teores das resinas utilizados.

Produção e avaliação do desempenho de painéis de partículas de madeira a partir de resíduos de podas de árvores urbanas

As especies utilizadas na arborizacao urbana requerem periodicas podas para atender aosrequisitos peculiares das essencias e para garantir a seguranca em relacao as redes eletricase de telefonia. O grande volume de material oriundo das podas tem potencial para, naforma de particulas, ser empregado na producao de paineis para emprego na confeccaode moveis e para aplicacao como componente de edificacoes. No presente trabalho, utilizaram-se residuos de poda de arvores de Canelinha (Nectandra lanceolata), obtidos na cidadede Sao Carlos (SP). Foram produzidos paineis de madeira aglomerada, tendo comoadesivo a resina poliuretana bicomponente a base de oleo de mamona, desenvolvida noInstituo de Quimica de Sao Carlos, da USP. Os parâmetros de processo foram: particulasde dimensao maxima 2,8 mm; porcentagem de adesivo 16%; temperatura de prensagem:90oC; tempo de prensagem: dez minutos. Os ensaios para avaliacao do desempenho dospaineis produzidos foram feitos de acordo com as recomendacoes da NBR 14810:2006,da Associacao Brasileira de Normas Tecnicas. Os resultados evidenciaram a viabilidadetecnica da referida producao, pois boa parte dos requisitos normativos foi atingida. Ajustesnos parâmetros de processo, principalmente no que tange a temperatura de prensagem,serao necessarios para que os paineis atendam a todos os requisitos da NBR 14810:2006

Production and characterization of MDF using eucalyptus fibers and castor oil-based polyurethane resin

The growing popularity of wooden panels renders this market segment increasingly competitive. MDF (Medium Density Fiberboard), in particular, is widely employed for a variety of applications, including civil construction, furniture, and packaging. This paper discusses a study of MDF produced from alternative raw materials, i.e., Eucalyptus fibers and castor-oil-based polyurethane resin. Physical and mechanical tests were performed to determine the MDF's modulus of elasticity and modulus of rupture in static bending tests, its swelling, water absorption, moisture and density. The results of the physical and mechanical characterization of this laboratory-produced MDF are discussed and compared with the Euro MDF Board standard. MDF produced with eucalyptus fiber and castor-oil-based polyurethane resin presents results very satisfactory.