This paper describes the effect of multi walled carbon nanotubes (MWCNTs) on the properties, especially the strength properties of rigid polyurethane (PU) foams produced from palm oil based polyol (POP) and methylene diphenyl diisocyanate (MDI). The foam composites in the ratio of 1:1.1 (wt. %) mixed at speed 2000 rpm. The addition of MWCNTs into PU foam are varies from 0 wt. % to 3 wt. %. The properties evaluated were compressive strength, density and energy absorption. Compressive strength of PU foam composites with 0.5% of MWCNTs showed the highest value 1.162 MPa of compressive strength compared to other foam composites. It was proved by modeling displacement nodal magnitude using NX Software (version 8.5). The density was increased 15.69 % with addition of 0.5 % MWCNTs into the PU foam. Increasing the amount of MWCNTs in PU foam was found to improve the energy absorption from 22.89 J for pure PU to 24.53 J for foam composites with 3 % MWCNTs.

Polymer nanocomposites have a great interest because of special properties of carbon nanotubes (CNTs) as excellent for mechanical, chemical, electrical and thermal properties. CNTs are categorized as single walled nanotubes (SWCNTs) and multi walled nanotubes (MWCNTs). The largest challenge is how to achieve uniform distribution of CNTs within the polymer matrix due to CNTs tend to agglomerated because of their hydrophobic nature. The resulted from CNTs bundles or aggregates reduced the mechanical performance of the final polymer nanocomposites. The surface of the CNTs must be modifiy to reduce the hydrophobicity and improved the interfacial adhesion to a bulk polymer. This paper reviewed the two (2) treatments of CNTs such as physical methods and chemical methods to obtain a better dispersion and enhance the CNTs properties in polymer nanocomposites.

Deformation and energy absorption characteristic of biomass foam composites are important in crashwortyness efficiency. The type of foam that had been used in this research is polyurethane (PU) foam with plant-based filler which are turmeric powder (Curcuma Longa), charcoal powder, henna powder (Lawsonia inermis) and lemon grass powder (Cymbopogon) that give natural color to the composites. The percentages of filler was specified to 10% by weight. PU foam was prepared by reaction of natural oil polyol and isocyanate with a ratio of 1 to 1.1 by weight. The mixture was stirred with 1500 rpm and was poured into the mould when mixture starting to expand. Band saw was used to cut the sample with desired dimension. The characterization of filler was done using Fourier Transform Infrared Spectroscopy (FTIR). Compression was tested using Ultimate Testing Machine (UTM) and scale to weigh the sample. Composites with henna filler have ductile like behavior that proved in stress-strain curved that show the rough line in the graph. Other composites have rigid like behavior which have a smooth line in a stress - strain curve.

The foam was prepared by mixing the polyols, isocyanate and carbonnanotubes (CNTs) at 1000 rpm speed. The different content of the CNTs are varies from 0 3 (0, 0.5, 1.5, 2.0, 2.5, 3.0) percent by weight. The foam sandwich was prepared by using hand lay-up method with epoxy and hardener as the adhesive to bind the surface between Polyurethane (PU) - CNTs and Aluminium (Al) sheet. The effect of different CNTs content was studied on the compression test and energy absorption. The compression test results show fluctuated values with increasing percentage of CNTs in PU foam. This trend may due to particles agglomeration as the nanosize of CNTs can make the particles to agglomerate easily due to the strong adhesive force between the nanoparticles. The size of the CNTs particles might not similar thus it is believed that the distribution of the particles were not well. Increasing in percentages of CNTs in PU foam found to improve the energy absorption from 0.115 J for control PU foam to 0.140 J for PU-CNTs foam with 3% CNTs.

This study is concerned on evaluation of laminated composites of aluminium (Al) sheet and floral foam (FF) under flexural and compression test. Effect of different layers of Al/FF laminated composites was evaluated. Epoxy and hardener was used as the adhesive to bind the surface between the Al sheet and FF. The information on the functional group that exists in FF during the formation of the foam was verified by Fourier Transform Infrared Spectroscopy (FTIR) analysis. From flexural and compression test, the mechanical properties decreased with the increasing number of layers of Al/FF laminated composites. The load cannot be distributed uniformly across the composite layer thus results in failure. Optical Microscope (OM) was used to see the adhesion between the layers of Al/FF laminated composites. One layer (1L) of Al/FF shows good adhesion while for four layer (4L) of the composites show phase separation and the excess adhesive around the interface. This shows that the adhesion between the layers also contribute to the failure of the laminated composite. FTIR analysis shows that the FF consists of amine group (at 3587.95 cm-1), alcohol group (at 3305.35 cm-1) and alkyl group (>900 cm-1) which is the main functional group found in polyurethane foam.