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1.
J Am Oil Chem Soc ; 92: 243-255, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25684774

RESUMEN

Transesterification of palm olein with glycerol can increase the functionality by introducing additional hydroxyl groups to the triglyceride structure, an advantage compared to using palm olein directly as feedstock for producing palm-based polyol. The objective of this study was to synthesize transesterified palm olein-based polyol via a three-step reaction: (1) transesterification of palm olein, (2) epoxidation and (3) epoxide ring opening. Transesterification of palm olein yielded approximately 78 % monoglyceride and has an hydroxyl value of approximately 164 mg KOH g-1. The effect of formic acid and hydrogen peroxide concentrations on the epoxidation reaction was studied. The relationships between epoxide ring-opening reaction time and residual oxirane oxygen content and hydroxyl value were monitored. The synthesized transesterified palm olein-based polyol has hydroxyl value between 300 and 330 mg KOH g-1 and average molecular weight between 1,000 and 1,100 Da. On the basis of the hydroxyl value and average molecular weight of the polyol, the transesterified palm olein-based polyol is suitable for producing rigid polyurethane foam, which can be designed to exhibit desirable properties. Rigid polyurethane foams were synthesized by substituting a portion of petroleum-based polyol with the transesterified palm olein-based polyol. It was observed that by increasing the amount of transesterified palm olein-based polyol, the core density and compressive strength were reduced but at the same time the insulation properties of the rigid polyurethane foam were improved.

2.
J Oleo Sci ; 64(1): 101-15, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25492233

RESUMEN

Polyols were synthesized from epoxidized natural oils and tetrahydrofuran through ring opening copolymerization catalyzed by Lewis acid. The properties of these polyols depend on the type of natural oils as well as the reaction conditions (monomer concentration, catalyst amount, reaction temperature and reaction time). These polyols were evaluated as a raw material for making polyurethane (PU) in order to understand the structure-property relationship between a natural oil and PU made from it. The tensile test analysis shows that the incorporation of natural oil moiety into the PU polymer network improves the elasticity of these PU samples when compared to a benchmark PU sample. In addition, the PU samples made from palm oil and soybean oil based polyols exhibit better tensile strength than benchmark PU. These polyols samples are suitable for making elastomeric PU, where high flexibility (high elongation at break) of PU is a common requirement.


Asunto(s)
Furanos/química , Aceites de Plantas/química , Polímeros/química , Poliuretanos/síntesis química , Aceite de Soja/química , Catálisis , Fenómenos Químicos , Elasticidad , Elastómeros , Ácidos de Lewis/química , Fenómenos Químicos Orgánicos , Aceite de Palma , Polimerizacion , Temperatura , Resistencia a la Tracción , Factores de Tiempo
3.
J Oleo Sci ; 64(1): 41-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25519290

RESUMEN

Hydrazide derivatives have been synthesized from methyl esters, hydrazones and vegetable oils. They are important due to their diverse applications in pharmaceutical products, detergents as well as in oil and gas industries. The chemical synthesis of fatty hydrazides is well-established; however, only a few publications described the synthesis of fatty hydrazide derivatives, particularly, when produced from refined, bleached and deodorized palm olein. Here, the synthesis and characterization of N,N-dimethyl fatty hydrazides are reported. The N,N-dimethyl fatty hydrazides was successfully synthesized from fatty hydrazides and dimethyl sulfate in the presence of potassium hydroxide with the molar ratio of 1:1:1, 6 hours reaction time and 80℃ reaction temperature in ethanol. The product yield and purity were 22% and 89%, respectively. The fatty hydrazides used were synthesized from refined, bleached and deodorized palm olein with hydrazine monohydrate at pH 12 by enzymatic route. Fourier transform infrared, gas chromatography and nuclear magnetic resonance (NMR) spectroscopy techniques were used to determine the chemical composition of N,N-dimethyl fatty hydrazides. Proton NMR confirmed the product obtained were N,N-dimethyl fatty hydrazides.


Asunto(s)
Ácidos Grasos/síntesis química , Hidrazinas/síntesis química , Aceites de Plantas/química , Cromatografía de Gases , Etanol , Calor , Hidrazinas/química , Concentración de Iones de Hidrógeno , Hidróxidos/química , Espectroscopía de Resonancia Magnética , Fenómenos Químicos Orgánicos , Aceite de Palma , Compuestos de Potasio/química , Espectroscopía Infrarroja por Transformada de Fourier , Ésteres del Ácido Sulfúrico/química
4.
Molecules ; 17(10): 11729-47, 2012 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-23044711

RESUMEN

Poly(lactic acid) (PLA) is known to be a useful material in substituting the conventional petroleum-based polymer used in packaging, due to its biodegradability and high mechanical strength. Despite the excellent properties of PLA, low flexibility has limited the application of this material. Thus, epoxidized palm olein (EPO) was incorporated into PLA at different loadings (1, 2, 3, 4 and 5 wt%) through the melt blending technique and the product was characterized. The addition of EPO resulted in a decrease in glass transition temperature and an increase of elongation-at-break, which indicates an increase in the PLA chain mobility. PLA/EPO blends also exhibited higher thermal stability than neat PLA. Further, the PLA/1 wt% EPO blend showed enhancement in the tensile, flexural and impact properties. This is due to improved interaction in the blend producing good compatible morphologies, which can be revealed by Scanning Electron Microscopy (SEM) analysis. Therefore, PLA can be efficiently plasticized by EPO and the feasibility of its use as flexible film for food packaging should be considered.


Asunto(s)
Compuestos Epoxi/química , Ácido Láctico/química , Aceites de Plantas/química , Polímeros/química , Rastreo Diferencial de Calorimetría , Fenómenos Mecánicos , Microscopía Electrónica de Rastreo , Aceite de Palma , Plastificantes/química , Poliésteres , Temperatura , Termogravimetría , Difracción de Rayos X
5.
Int J Mol Sci ; 13(5): 5878-5898, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22754338

RESUMEN

In this work, poly(lactic acid) (PLA) a fully biodegradable thermoplastic polymer matrix was melt blended with three different epoxidized palm oil (EPO). The aim of this research was to enhance the flexibility, mechanical and thermal properties of PLA. The blends were prepared at various EPO contents of 1, 2, 3, 4 and 5 wt% and characterized. The SEM analysis evidenced successful modification on the neat PLA brittle morphology. Tensile tests indicate that the addition of 1 wt% EPO is sufficient to improve the strength and flexibility compared to neat PLA. Additionally, the flexural and impact properties were also enhanced. Further, DSC analysis showed that the addition of EPO results in a decrease in T(g), which implies an increase in the PLA chain mobility. In the presence of 1 wt% EPO, TGA results revealed significant increase in the thermal stability by 27%. Among the three EPOs used, EPO(3) showed the best mechanical and thermal properties compared to the other EPO's, with an optimum loading of 1 wt%. Conclusively, EPO showed a promising outcome to overcome the brittleness and improve the overall properties of neat PLA, thus can be considered as a potential plasticizer.


Asunto(s)
Plásticos Biodegradables/química , Compuestos Epoxi/química , Ácido Láctico/química , Aceites de Plantas/química , Plastificantes/química , Polímeros/química , Rastreo Diferencial de Calorimetría , Microscopía Electrónica de Rastreo , Aceite de Palma , Poliésteres , Temperatura , Resistencia a la Tracción , Termogravimetría
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