The effect of palm oil polyol crosslinking on the mechanical and shape memory properties of polyurethane (PU) polymer was investigated and compared with linear PU. The PU was composed of polycaprolactonediol (PCL), palm oil polyol, 4,4-diphenylmethane diisocyanate (MDI) and 1,4-butanediol (BD). Palm oil polyol was introduced due to its large number of functional groups, hyperbranched structure and easy availability. The shape fixity decreased with addition of palm oil polyol while shape recovery increased and showed an optimum value with the addition of palm oil polyol. The mechanical properties improved with the addition of palm oil polyol in regards with linear PU. Copyright � (2012) Asian-Australasian Association for Composite Materials (AACM).

Surface treatment of aluminium alloy plays a significant role in improving the strength of the adhesive bond. In this study, an aluminium alloy 2024-T3 was treated by two different methods of surface treatments i.e. by alkaline etching and warm water treatment followed by silanization method in order to enhance the adhesive bonding. Three different formulations of polyurethane adhesive by varying the NCO:OH ratios which were prepared from polyol polycaprolactone (PCL) based on palm kernel oil polyesteramide (PPKO) with a blend of aromatic and cycloaliphatic diisocyanate. Surface morphology, surface chemical analysis, wettability and surface roughness of the treated samples were characterised using field emission scanning electron microscopy and energy dispersive X-ray analysis (FESEM/EDX), X-Ray Photoelectron Spectroscopy (XPS), contact angle goniometry and surface profilometry, respectively. The influences of surface treatment techniques and conditions on durability of the joint strength and interfacial properties were explored by performing the single lap shear test and wedge test. The effects of NCO:OH ratios on PU adhesive strength were also investigated. Durability of PU adhesive bonding is found to display an interesting dependence on the surface treatments. � 2014 Elsevier Ltd.

In order to enhance the adhesive bonding, two different methods of surface treatments have been carried out on aluminum alloy 2024-T3 substrate i.e. alkaline etching and silane treatment. The topology and surface chemical analyses of treated alloy were investigated by AFM and XPS, respectively. The effect of surface treatments on the wettability and adhesive bonding strength were also studied. Three different formulations of polyurethane adhesive by varying the NCO: OH ratio that were prepared from the reaction of green polycaprolactone (PCL) polyol and diisocyanate. Silane treatment showed better wettability and adhesive bonding strength compared to alkaline etching surface treatment. � 2014 Faculty of Mechanical Engineering.

Aluminum alloy 2024-T3 was treated by two different methods of surface treatments i.e. by alkaline etching and warm water treatment followed by silanization method in order to enhance the adhesive bonding. The effects of both the substrate surface condition and the adhesive properties on single-lap shear resistance were analysed. Three different formulation of polyurethane adhesive by varying the NCO:OH ratio which were prepared from polyol based on polycaprolactone (PCL)/palm kernel oil (PKO) with an aromatic and cycloaliphatic diisocyanate. Moreover, wettability tests were performed in order to evaluate the effect of all parameters mentioned above on the substrate/adhesive interaction. Surface treatment with warm water and ?- GPS gives better wettability and adhesive bonding compared to alkaline etching surface treatment. � (2013) Trans Tech Publications, Switzerland.

Polyurethane (PU) adhesives were prepared from three different polyols based on polycaprolactone (PCL)/palm kernel oil (PKO) with an aromatic and cycloaliphatic diisocyanate. The adhesives were characterized through Fourier Transformer Infrared (FTIR) spectroscopy in order to ensure the formation of urethane and the completeness of polymer reaction. The effects of NCO/OH ratios and types of diisocyanate on PU adhesive strength were investigated. The adhesive strength of metal to metal bonding was determined by single lap shear joint testing. The correlation between crosslinking of PU network and adhesive strength was also studied by performing swelling tests. � (2014) Trans Tech Publications, Switzerland.

Thermoplastic polyurethane (TPU) nanocomposites were prepared using polycaprolactonediol as the soft segment, 4,4'-diphenylmethane diisocyanate as the hard segment, 1,4-butanediol and palm oil polyol. Nanoclay with certain weight percent (wt%) was reinforced as filler to improve both mechanical and shape memory behavior of the nanocomposites. Palm oil polyol was introduced in order to provide hyperbranched structure for better dispersion of filler in the matrix as well as aiding the crosslinking process. The experimental results showed that the mechanical and shape memory behavior of clay reinforced polyurethane nanocomposites were influenced by clay weight percent in the polymer matrix. TPU with 3 wt% clay showed optimum values of mechanical properties while the shape memory behavior decreases with increasing clay content. � (2012) Trans Tech Publications, Switzerland.