ABSTRACT: The mechanical properties (tensile, flexural, and impact properties) and water absorpti... more ABSTRACT: The mechanical properties (tensile, flexural, and impact properties) and water absorption of oil palm empty fruit bunches (OPEFB) reinforced in new unsaturated polyester composites were studied. New OPEFB reinforced polyester composite derived from new unsaturated polyester resin containing bis-(2-hydroxylethyl) fumarate (monomer I) which was synthesized from ethylene glycol with fumaric acid in the presence of P-toluene sulfonic acid as catalyst was prepared. The chemical structure was confirmed by CHN analysis, FT-IR, and 1H-NMR spectroscopy. New unsaturated polyester was carried out by the condensation reaction between terepthaloyl chloride and monomer I. The chemical structure of this polymer was confirmed by CHN analyses, FT-IR, 1H-NMR, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). KEY WORDS: bis-(2-hydroxyethyl) fumarate, synthesis, new unsaturated polyester, composite, oil palm empty fruit bunches.
Comparative Study of Two Twin Liquid-Crystalline Diglycidyl Ethers Containing Azomethine Moieties... more Comparative Study of Two Twin Liquid-Crystalline Diglycidyl Ethers Containing Azomethine Moieties R. Ratnamalar , A. M. Issam & A. Baharin To cite this article: R. Ratnamalar , A. M. Issam & A. Baharin (2011) Comparative Study of Two Twin Liquid-Crystalline Diglycidyl Ethers Containing Azomethine Moieties, Molecular Crystals and Liquid Crystals, 537:1, 128-140, DOI: 10.1080/15421406.2011.556449 To link to this article: http://dx.doi.org/10.1080/15421406.2011.556449
In the present investigation, a novel ladder polymer, poly(azomethine ester), was prepared via so... more In the present investigation, a novel ladder polymer, poly(azomethine ester), was prepared via solution polycondensation polymerization between terephthalic acid and the novel monomer. Terephthalic acid was regenerated from PET waste bottles by saponification process, whereas p-phenylenediamine was obtained via Hoffmann rearrangement method. A novel monomer, namely N,N′-bis(2,5-dihydroxy benzylidene)-1,4-diaminobenzene was prepared from the reaction of 2,5-di-hydroxybenzadehyde with p-phenylenediamine in the ratio of 2:1, respectively. For the first time a solution polycondensation method has been employed for the synthesis of a ladder polymer which is otherwise prepared commonly via Diels-Alder cycloaddition reaction. The synthesized ladder polymer was characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NMR), carbon nuclear magnetic resonance spectroscopy (13C NMR), elemental analysis (CHN), X-ray diffraction (XRD), d...
Nanocomposites comprising diol-vanilin and cadmium sulfide (CdS) has been synthesized via chemica... more Nanocomposites comprising diol-vanilin and cadmium sulfide (CdS) has been synthesized via chemical precipitation method in ethanol at refluxed temperature (160 oC) for 12 hours. CdCl2. 2.5H2O and thiourea as cadmium and sulfide precursors respectively were employed. Diol vanilin is a thermotropic liquid crystal monomer which exhibits enantiotropic nematic metaphase texture when observed under polarizing microscope and confirmed by DSC thermal stability study. A series of different mass composition of diol vanilin and CdS nanocomposites ranging from 0.1:1.0 till 1.0:1.0(w/w) were prepared and characterized using XRD, TEM, SEM-EDX, POM and DSC. The X-ray diffraction pattern (XRD) showed broad peaks due to the formation of cubic CdS nanoparticles in diol vanilin matrix. The nanocomposites at low mass composition of CdS still maintained their nematic phase. However, the liquid crystal property was affected when the mass composition of CdS in nanocomposite was increased and the liqu...
The enzymatic reaction pathway between the cholesterol/enzyme/electrode paper-based biosensor PB/... more The enzymatic reaction pathway between the cholesterol/enzyme/electrode paper-based biosensor PB/CPANI/SPE and cholesterol.
Bare cadmium sulfide (CdS) nanocrystals were successfully synthesized by the thermolysis of a sin... more Bare cadmium sulfide (CdS) nanocrystals were successfully synthesized by the thermolysis of a single-source organometallic precursor, cadmium chloride hemipentahydrate (CdCl2⋅2.5H2O) with thiourea in ethanol. The microstructure of the CdS samples was characterized using XRD, TEM, and Raman spectroscopy. The XRD's results showed that there was a transformation from cubic to hexagonal crystalline phase when higher mass ofCdCl2⋅2.5H2Owas used. Further experimental with differentCd2+source showed ionCl−originated fromCdCl2⋅2.5H2Oattributed to this crystalline phase transformation. The UV-Visible analysis indicated that quantum confinement effect took place when compared to the bulk CdS. However, the photoluminescence experiments revealed that the red-light emission was observed in all samples. This finding could be ascribed to deep trap defects that were due to sulfur vacancies as suggested by XPS and also the fact that the bare CdS nanoparticles are in contact with each other as sh...
Soda lignin extracted from oil palm empty fruit bunch fibres was used as a filler in an alkyd pai... more Soda lignin extracted from oil palm empty fruit bunch fibres was used as a filler in an alkyd paint. Studies on wooden test panels showed that the lignin improved opacity, surface drying time and adhesion, while also notably reducing swelling of the wood on outdoor exposure testing.
ABSTRACT Non-woven lignocellulosic fibres (oil palm empty fruit bunches (EFB), bamboo fibres and ... more ABSTRACT Non-woven lignocellulosic fibres (oil palm empty fruit bunches (EFB), bamboo fibres and pineapple leaf fibres) reinforced thermoset composites were fabricated at different fibre weight fractions, ie 10, 20, 30, 40 and 50%. The polyester resin (unsaturated) and ...
ABSTRACT A series of new epoxy resins containing azomethine groups were synthesized by condensati... more ABSTRACT A series of new epoxy resins containing azomethine groups were synthesized by condensation reaction. The structures were characterized and confirmed by FTIR, 1 H-NMR, 13C-NMR, UV and elemental analysis. Thermal stability and degradation behavior of these epoxy resins were examined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results of thermal analysis showed that, all resins possess high thermal stability. The epoxy resins based on p-hydroxybenzaldehyde exhibited high thermal stability as compared to 4-hydoxy-3-methoxybenzaldehyde. The resins produced showed good properties and can be used as matrix in polymer composites.
Two different twin liquid-crystalline diglycidyl ethers containing azomethine moieties were synth... more Two different twin liquid-crystalline diglycidyl ethers containing azomethine moieties were synthesized and characterized and their mesomorphic behaviors, thermal properties, and mechanical properties were compared. It was found that 4,4′-di(2,3-epoxypropoxy)-N-benzylidene-o-tolidine-cured systems gave higher thermal and mechanical properties than 3,3′-dimethoxy-4,4′-di(2,3-epoxypropoxy)-N-benzylidene-o-tolidine-cured systems. All liquid-crystalline behaviors exhibited by the products were found to be in the nematic phase. In addition, the higher curing ratios
ABSTRACT: The mechanical properties (tensile, flexural, and impact properties) and water absorpti... more ABSTRACT: The mechanical properties (tensile, flexural, and impact properties) and water absorption of oil palm empty fruit bunches (OPEFB) reinforced in new unsaturated polyester composites were studied. New OPEFB reinforced polyester composite derived from new unsaturated polyester resin containing bis-(2-hydroxylethyl) fumarate (monomer I) which was synthesized from ethylene glycol with fumaric acid in the presence of P-toluene sulfonic acid as catalyst was prepared. The chemical structure was confirmed by CHN analysis, FT-IR, and 1H-NMR spectroscopy. New unsaturated polyester was carried out by the condensation reaction between terepthaloyl chloride and monomer I. The chemical structure of this polymer was confirmed by CHN analyses, FT-IR, 1H-NMR, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). KEY WORDS: bis-(2-hydroxyethyl) fumarate, synthesis, new unsaturated polyester, composite, oil palm empty fruit bunches.
Comparative Study of Two Twin Liquid-Crystalline Diglycidyl Ethers Containing Azomethine Moieties... more Comparative Study of Two Twin Liquid-Crystalline Diglycidyl Ethers Containing Azomethine Moieties R. Ratnamalar , A. M. Issam & A. Baharin To cite this article: R. Ratnamalar , A. M. Issam & A. Baharin (2011) Comparative Study of Two Twin Liquid-Crystalline Diglycidyl Ethers Containing Azomethine Moieties, Molecular Crystals and Liquid Crystals, 537:1, 128-140, DOI: 10.1080/15421406.2011.556449 To link to this article: http://dx.doi.org/10.1080/15421406.2011.556449
In the present investigation, a novel ladder polymer, poly(azomethine ester), was prepared via so... more In the present investigation, a novel ladder polymer, poly(azomethine ester), was prepared via solution polycondensation polymerization between terephthalic acid and the novel monomer. Terephthalic acid was regenerated from PET waste bottles by saponification process, whereas p-phenylenediamine was obtained via Hoffmann rearrangement method. A novel monomer, namely N,N′-bis(2,5-dihydroxy benzylidene)-1,4-diaminobenzene was prepared from the reaction of 2,5-di-hydroxybenzadehyde with p-phenylenediamine in the ratio of 2:1, respectively. For the first time a solution polycondensation method has been employed for the synthesis of a ladder polymer which is otherwise prepared commonly via Diels-Alder cycloaddition reaction. The synthesized ladder polymer was characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NMR), carbon nuclear magnetic resonance spectroscopy (13C NMR), elemental analysis (CHN), X-ray diffraction (XRD), d...
Nanocomposites comprising diol-vanilin and cadmium sulfide (CdS) has been synthesized via chemica... more Nanocomposites comprising diol-vanilin and cadmium sulfide (CdS) has been synthesized via chemical precipitation method in ethanol at refluxed temperature (160 oC) for 12 hours. CdCl2. 2.5H2O and thiourea as cadmium and sulfide precursors respectively were employed. Diol vanilin is a thermotropic liquid crystal monomer which exhibits enantiotropic nematic metaphase texture when observed under polarizing microscope and confirmed by DSC thermal stability study. A series of different mass composition of diol vanilin and CdS nanocomposites ranging from 0.1:1.0 till 1.0:1.0(w/w) were prepared and characterized using XRD, TEM, SEM-EDX, POM and DSC. The X-ray diffraction pattern (XRD) showed broad peaks due to the formation of cubic CdS nanoparticles in diol vanilin matrix. The nanocomposites at low mass composition of CdS still maintained their nematic phase. However, the liquid crystal property was affected when the mass composition of CdS in nanocomposite was increased and the liqu...
The enzymatic reaction pathway between the cholesterol/enzyme/electrode paper-based biosensor PB/... more The enzymatic reaction pathway between the cholesterol/enzyme/electrode paper-based biosensor PB/CPANI/SPE and cholesterol.
Bare cadmium sulfide (CdS) nanocrystals were successfully synthesized by the thermolysis of a sin... more Bare cadmium sulfide (CdS) nanocrystals were successfully synthesized by the thermolysis of a single-source organometallic precursor, cadmium chloride hemipentahydrate (CdCl2⋅2.5H2O) with thiourea in ethanol. The microstructure of the CdS samples was characterized using XRD, TEM, and Raman spectroscopy. The XRD's results showed that there was a transformation from cubic to hexagonal crystalline phase when higher mass ofCdCl2⋅2.5H2Owas used. Further experimental with differentCd2+source showed ionCl−originated fromCdCl2⋅2.5H2Oattributed to this crystalline phase transformation. The UV-Visible analysis indicated that quantum confinement effect took place when compared to the bulk CdS. However, the photoluminescence experiments revealed that the red-light emission was observed in all samples. This finding could be ascribed to deep trap defects that were due to sulfur vacancies as suggested by XPS and also the fact that the bare CdS nanoparticles are in contact with each other as sh...
Soda lignin extracted from oil palm empty fruit bunch fibres was used as a filler in an alkyd pai... more Soda lignin extracted from oil palm empty fruit bunch fibres was used as a filler in an alkyd paint. Studies on wooden test panels showed that the lignin improved opacity, surface drying time and adhesion, while also notably reducing swelling of the wood on outdoor exposure testing.
ABSTRACT Non-woven lignocellulosic fibres (oil palm empty fruit bunches (EFB), bamboo fibres and ... more ABSTRACT Non-woven lignocellulosic fibres (oil palm empty fruit bunches (EFB), bamboo fibres and pineapple leaf fibres) reinforced thermoset composites were fabricated at different fibre weight fractions, ie 10, 20, 30, 40 and 50%. The polyester resin (unsaturated) and ...
ABSTRACT A series of new epoxy resins containing azomethine groups were synthesized by condensati... more ABSTRACT A series of new epoxy resins containing azomethine groups were synthesized by condensation reaction. The structures were characterized and confirmed by FTIR, 1 H-NMR, 13C-NMR, UV and elemental analysis. Thermal stability and degradation behavior of these epoxy resins were examined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results of thermal analysis showed that, all resins possess high thermal stability. The epoxy resins based on p-hydroxybenzaldehyde exhibited high thermal stability as compared to 4-hydoxy-3-methoxybenzaldehyde. The resins produced showed good properties and can be used as matrix in polymer composites.
Two different twin liquid-crystalline diglycidyl ethers containing azomethine moieties were synth... more Two different twin liquid-crystalline diglycidyl ethers containing azomethine moieties were synthesized and characterized and their mesomorphic behaviors, thermal properties, and mechanical properties were compared. It was found that 4,4′-di(2,3-epoxypropoxy)-N-benzylidene-o-tolidine-cured systems gave higher thermal and mechanical properties than 3,3′-dimethoxy-4,4′-di(2,3-epoxypropoxy)-N-benzylidene-o-tolidine-cured systems. All liquid-crystalline behaviors exhibited by the products were found to be in the nematic phase. In addition, the higher curing ratios
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