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The rigid polyurethane (PU) were produced using ionic liquid (IL) modified multi walled carbon nanotubes (MWCNTs) by reaction of palm oil based polyol (POP) with methylene diphenyl diisocyanate (MDI). The 1-butyl-3-methylimidazolium tetrafluoborate (BMIMBF4) used as IL to disperse MWCNTs in PU foam by grinding in ratio 1:3 by weight of MWCNTs to IL till black paste were obtained. The effects of different percentage of modified MWCNTs (0.0 - 3.0 %) on Polyurethane / Multi Walled Carbon Nanotubes / Ionic Liquid (PMI) foam composites were evaluated in density, morphology and compressive strength. The density were increased higher 0.0538 kg / m3 at 3.0 % PMI. The average cell size value higher without addition modified MWCNTs and scanning electron microscopy (SEM) showed inhomogenously structure with addition of modified MWCNTs. Compressive strength with 0.5 % PMI showed the highest value 1.671 MPa compared to other PMI.

Powder metallurgy metal matrix composites based on AZ91 alloy matrix reinforced with 0.3, 0.6 and 0.9 weight percent of multiwall carbon nanotube (MWCNT) were investigated from the point of view of their response to artificial ageing as compared to the unreinforced AZ91 matrix alloy. Mg-Zn-Al (AZ91) and its composite were prepared by milling the raw materials and followed by sintering at 450°C for 2 hours. The sintered samples were solution treated at 415°C for 2 hours and followed by artificial ageing at 175°C. The ageing behavior was monitored by following the phase analysis and hardness of the samples examined. Microstructure of the sintered composites indicated that MWCNT was embedded in the AZ91 matrix alloy. All composites indicated lower hardness than matrix, however AZ91reinforced with 0.6 and 0.9 weight percent of CNT showed accelerated ageing. X-ray diffraction pattern indicated the present of β-phase (Mg17Al12) that responsible for the hardening behavior.

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.

Polyurethane (PU)/multiwalled carbon nanotubes (MWCNTs) foam composites were produced by reaction of based palm oil polyol (POP) with methylene diphenyl diisocyanate (MDI). The MWCNTs were added into PU foam with the percentages varied from 0 wt.% to 3 wt.%. Sandwich composites were prepared using hand lay-up method where Aluminium (Al) sheet as skin were stacked onto PU foam using Araldite adhesives. The PU/MWCNTs foam composites (PMFC) and PU/MWCNTs foam sandwich composites (PMFSC) were characterized using flexural test analysis. Observation showed higher value of flexural strength for PMFC and PMFSC at 0.5% incorporation of MWCNTs. The flexural strength of sandwich PU foam is higher with an average value of 159.38% than control PU foam, due to Al sheet act as ductile skin and prevents samples from rupture rapidly. The modeling using finite element analysis (NX Software-version 8.5) showed the displacement nodal magnitude for 0.5% PMFC (2.537 mm) are higher than 0.5% PMFSC (0.288 mm).

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.

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 chemical modification of bagasse fiber (BF) filled polypropylene (PP) composites compounding using two roll mill. The fibers were chemically modified with different chemical treatment (alkaline, acetic acid and silane coupling agent). Effect of chemical modification towards BF/PP composites was evaluated by tensile test and flexural test. The chemical modification efficiency was verified by Fourier Transform Spectrometer (FTIR) analysis. From FTIR analysis, there is an increase on intensity on acetyl group (C-H) indicated the existing of chemical bonding between PP and BF. Chemical modified composites increased the mechanical behavior. Composites that modified with acetylation (acetic acid) shows better mechanical properties compared to others.