In this study, palm oil-based polyurethane (PU)/montmorillonite (MMT) nanocomposite foams were produced via an in situ polymerization method. The palm oil-based polyol synthesized by transesterification reaction of palm oil and pentaerythritol was reacted with commercial polymeric diphenylmethane diisocyanate in the presence of water (blowing agent), N,N-dimethylcyclohexylamine (catalyst), polydimethylsiloxane (surfactant) and MMT to produce rigid PU nanocomposite foams. The obtained foams containing different MMT contents (1, 3, and 5 wt%) were characterized for their structure, morphology, density, hardness, compressive strength and thermal stability. X-ray diffraction patterns revealed that the nanocomposites formed were exfoliated. Scanning electron micrographs showed that the cells of the obtained PU foams were closed cells. The nanocomposite foams showed a higher number of cells with a smaller cell size as the amount of MMT increased. The density and the compressive strength of the foams increased with the increasing amount of MMT and were in the range of 38.5—46.6 kg/m3 and 116.7—171.6 kPa, respectively. Moreover, addition of MMT also improved the thermal stability of the foams.

Water-reducible acrylic-alkyd resins were synthesized from the reaction between monoglycerides prepared from modified palm oil and carboxy-functional acrylic copolymer followed by neutralization of carboxyl groups with diethanolamine. Modified palm oil was produced by interesterification of palm oil with tung oil at a weight ratio of 1 : 1, using sodium hydroxide as a catalyst, whereas carboxy-functional acrylic copolymer was prepared by radical copolymerization of n-butyl methacrylate and maleic anhydride. The amount of acrylic copolymer used was from 15 to 40% by weight, and it was found that homogeneous resins was obtained when the copolymer content was 20 -35 wt %. All of the prepared water-reducible acrylic-alkyd resins were yellowish viscous liquids. Their films were dried by baking at 190°C and their properties were determined. These films showed excellent water and acid resistance and good alkali resistance.

In this research, poly(vinyl chloride) (PVC)/ethylene vinyl acetate copolymer (EVA)/ organomodified montmorillonite (OMMT) nanocomposites have been prepared and characterized for their structure, properties, and morphology. The blend nanocomposites were prepared through the melt mixing of PVC/EVA at weight ratios of 100/2.5, 100/5, 100/7.5, and 100/10 with various amounts of OMMT (2, 4 and 6 phr) on a two-roll mill followed by compression molding. Before mixing with PVC and EVA, montmorillonite (MMT) was modified with octadecylamine via the cationic exchange reaction. X-ray diffraction patterns revealed that the nanocomposites formed were intercalated. Scanning electron micrographs of the fractured surface showed a reduction of EVA and OMMT distribution when more was added into the PVC matrix. In the present study, the OMMT of 2 phr dispersed in the 100 PVC/5 EVA matrix showed high potential on improving the impact strength of the nanocomposite. This may be due to the synergistic effect of the EVA and OMMT that enhanced the toughness of the nanocomposite.

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Waste poly(ethylene terephthalate) (PET) bottles were glycolyzed by propylene glycol (PG) at a weight ratio of PET to PG of 37.5 : 62.5 using zinc acetate as a catalyst. The glycolyzed product, consisting of oligomeric diols with a number-average molecular weight range of 458 -844, was obtained. It was further reacted with soybean oil and toluene diisocyanate to obtain urethane oils at hydroxyl to isocyanate ratios from 1 : 1 to 1 : 0.7, with and without methanol acting as a blocking agent. All the synthesized urethane oils were yellowish, transparent, low-viscosity liquids of low molecular weights. A lower diisocyanate content and the presence of a blocking agent resulted in higher viscosity, higher molecular weight, and shorter drying time. The films of all synthesized urethane oils exhibited good hardness and adhesion. They also showed excellent water and acid resistance but only fair alkali resistance. However, these prepared urethane oils had lower flexibility and poorer wear resistance compared to those of the commercial urethane oil.