Polycaprolactone (PCL) polyol was prepared by a ring opening polymerization of ?- caprolactone initiated by palm kernel oil (PKO) based polyol and 1,6-hexanediol to form a PCL/PKO based polyol. The properties of polyol were varied by their initiator:co-initiator weight ratio. The completion of polyol formation was characterized through Fourier Transformation Infrared (FTIR) spectroscopy. Other parameters such as acid number and hydroxyl number of polyol were also studied to monitor the progress of reaction. FTIR results showed the significant changes particularly for the OH and C=O stretching peaks. � (2012) Trans Tech Publications, Switzerland.

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.

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.

Polyurethane has been widely used in various coating industries due to its good weathering resistance, promising appearance, excellent elasticity and good mechanical properties. The present work reports the development of polycaprolactone urethane coatings based on waste palm cooking oil (WPCO). WPCO was recycled to synthesis polycaprolactone (PCL) polyol using two-steps methods; transesterification and ring opening polymerization with various ratios of ?-CL to WPCO based polyesteramide. The WPCO based PCL polyols were reacted with isophorone diisocyanate (IPDI) to produce polycaprolactone urethane coatings. FTIR analyses were employed to confirm the formation of polyols and the scratch resistance properties of coatings were characterized by scratch hardness testing. The results revealed that the scratch resistance of polycaprolactone urethane coatings increased by increasing the ?-CL composition in the formulation. � 2019 Trans Tech Publications, Switzerland.

The main objective of this study was to investigate the effect of different types and molecular weight (MW) of polyol on the shape memory properties of palm kernel oil-based shape memory polyurethane (SMPU) prepared by two step bulk polymerization procedure. Poly(ethylene glycol) (PEG) and poly(?-caprolactone) (PCL) with MW 2000 and MW 4000 were used as the main material for soft segment. The addition of palm kernel oil polyol (PKO-p) in the SMPU system is due to the concern of the renewable resources. Shape fixity and shape recovery properties were investigated using bending test to evaluate the shape memory effect. The results indicate that the shape fixity of SMPU depends primarily on the types of polyol whereas MW had a slight effect towards the shape fixity. SMPU synthesized from PEG with MW 2000 performed a good shape fixity, about 96% compared to that of PCL with MW 2000, about 29%. In the case of PCL - based SMPU, the increase of shape fixity is proportional to the increase of MW. All samples, except the one based on PEG4000, exhibited excellent shape recovery (100%). � 2019 Elsevier Ltd. All rights reserved.

The evolution of responsive polymers has amplified expressively in consequence of the growth of precise polymer architecture with predetermined structure-to-property behavior. In this study, new thermal responsive self-healing polycaprolactone urethane coatings were prepared from waste palm cooking oil. Nine different formulations of coatings with various percentages of ε-caprolactone (ε-CL) were successfully developed and the effect of polycaprolactone network in the polyurethane coating on the self-healing behavior. The remendability of the coatings was studied by using thermal analysis and dynamic mechanical analysis. The PCLU coating with the highest content of PCL network was nearly completely healed after 2 hours at 90ºC. The results were confirmed by scanning electron microscopy before and after healing. The mechanism of scratch closure by thermal stimuli-responsive self-healing was also discussed.