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\section{Introduction}  The need for alternative foam products has become a priority in several fronts; foams are present in two main areas, food packing and insulations, with outstanding performance, low  density and high thermal insulation makes them perfect, but both applications have a very short  life cycle and then an undesirable recyclability or biodegradability.    Polyurethane (PU) is one of the most versatile and intensively used industrial materials. By the proper selection of reactants and changing percentage of the component in the formula, the  resulting polyurethane can be elastomer, thermoplastic, thermosetting, rigid and flexible foams.  Rigid polyurethane foams can be used as construction materials, such as polymeric concrete 
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bio-based polyols have been developed from vegetable oils such as soybean oil, canola oil, palm  oil and castor oil, due to the environmental and sustainable issues in recent years [1-5]. Developing  bio-renewable feedstock for industry is crucial now for both the economic and environmental  reasons. Soybean oil is an annually renewable natural resource for the polyols and is available in large  quantities. For each pound of soybean oil produced, 2.67 pounds of carbon dioxide are removed  from the air [1]. Soy-based polyols can be used in various polyurethane applications by selecting  proper functional groups and side chains. Polyurethanes produced from soy-based polyols  normally exhibit equivalent or improved physical and chemical properties due to the hydrophobic  nature of triglycerides.    The selection of the Kenaf core is due to the great availability, representing more than 60% of  the Kenaf plant, and not being as desired as the fiber portion of the plant that has a higher demand,  the core also has a particular property that make it more desirable on foams, it is hydrophobic,  composites has increased the global demand for natural fiber crops. Kenaf is an annual species of  fiber crop which can grow to around 9 feet in 9 months.    When Composting PU together with other biomass waste, the biodegradation process can  happen within two weeks and the materials will be fully decomposed, having disappeared within  three to four weeks. Since the introduction of the Soy base PU, we decided to verify the industrial  compost ability of the foams and its rate. A final verification was needed to determine the degree  of toxicity in the remaining compost, Phytotoxicity, a detrimental deviation from the normal  pattern of appearance and growth of plants in response to a given substance, is designed to assess  potential effects of substances on seedling emergence and growth. As such it does not cover  chronic effects or effects on reproduction. Passing this test is without doubts a major indicator of  the compost suitability of final our product at the end of the life cycle.    The main objective of this research was to develop soy-based polyurethane foam reinforced  with Kenaf core and to investigate thermal properties, furthermore, the effect of Kenaf core  addiction when foaming the composite, the standardized compostability capacity of the foam in  the whole spectrum of samples and a final phytotoxicity test to proof a safe waste at the end of the  life cycle.    The main objective of this research was to develop soy-based polyurethane foam reinforced  with multi-walled carbon nanotubes to enhance the compressive and mechanical properties. Soy-  based polyurethane / carbon nanotubes composites with loadings of 0.5 and 1.0 wt% were  synthesized. The effects of kenaf content on the properties of soy-based polyurethane foam  composites were investigated.