Skip Navigation LinksVolume : Volume 4 No.1 1994

  
  
  
Abstract
  
  
  
immobilized_lipase_systems_for_modification_and_processing_of_lipids_-_a_review.pdfIMMOBILIZED  LIPASE SYSTEMS FOR MODIFICATION AND PROCESSING OF LIPIDS - A REVIEW
  
ABSTRACT:
In  principle, immobilized  lipase technology facilitates the development of continuous, large-scale commercial processes, which have a high efficiency per unit volume of reactor and a corresponding high rate of return of capital costs. Furthermore, the use of immobilized lipase lead to  a decrease in  the potential for contamination of the product via residual lipase, thus avoiding the need for downstream thermal treatment. Immobilization also permits multiple use of lipase and enhances its thermal and chemical stability, thus leading to predictable decay rates and enhances opportunities for better coritrol of both the  process and product quality. This review focuses on the use of immobilized lipase technology. The various immobilization procedures, reactor configurations, and process consideration are reviewed  and discussed.

AUTHOR:
Nazimah Sheik Abdul Hamid and Uma Devi M. Palanisamy*
19943/14/2017 12:12 PM1/18/2018 7:35 AM
liquid_state_1h_and_13c-nmr_studies_on_polymerisation_reaction_of_22-difurfuryloxy-2-_silapropane.pdfLIQUID STATE 1H AND 13C-NMR STUDIES ON POLYMERISATION REACTION OF 2,2'-DIFURFURYLOXY-2- SILAPROPANE
  
ABSTRACT:
The purpose of this study was to  prepare the copolymer of 2,2'-difurfuryloxy-2-silapropane (DFS) and 1, 1 '-(methylenedi-4, 1-phenylene) bismaleimide (BM). DFS was prepared at 0°C through the reaction of 2 moles of furfuryl alcohol (FA) with 1 mole of dichlorodimethylsilane (DCMS) in  the presence of pyridine and chloroform as a solvent. The formation of this compound was characterized by the 1H and 13C-NMR spectroscopy and mass spectrometry. DFS has the ability to undergo the Diels-Alder reaction. The furan end groups of DFS could react with dienophile groups of other materials. The adduct of DFS-BM was prepared by the reaction of DFS with BM at room temperature (18°C) in chloroform (CDCI). Characterization of the adduct was carried out through a study of the 1H and 13C-NMR spectra of the  adduct.
 
KEYWORDS: Furfuryl alcohol (FA), dichlorodimethylsilane (DCMS), 2,2'-difurfuryloxy-2-silapropane  (DFS),  1, 1 '-(methylenedi-4, 1-phenylene)  bismaleimide  (BM), condensation reaction,  Diels-Alder reaction.

AUTHOR:
Rusli Omar
19943/14/2017 12:12 PM1/18/2018 7:33 AM
rheology_study_of_rice_husk_ash_-_polypropylene_composite.pdfRHEOLOGY STUDY OF RICE HUSK ASH - POLYPROPYLENE COMPOSITE
  
ABSTRACT:
The rheological  properties of rice husk ash-polypropylene composite was studied using a Br~bender slit capillary rheometer.  The melt shear stress and viscosity increased with filler content.  The .filler was subsequently treated with  a silane-based coupling agent.  The silane used was Prosil 2020, a proprietary silane coupling agent containing the peroxide bis(t-butyl peroxy)di-isopropyl benzene.  The peroxide induces -scission of the polypropylene molecular chains reducing the shear stress and viscosity. Hence, the filler and the coupling agent (peroxide concentration) have opposing effect on the rheology of the composite's melt. For high filler content melt, the peroxide effect is more prominent lowering the overall stress and viscosity.  At higher shear rate, the effect of filler concentration is more dominant. Mixing torque and melt flow index studies support the, rheology measurements by the  slit die technique.

KEYWORDS: Polypropylene, rheology, rice husk ash, filler, composite, compounding, Prosil, coupling agent.

AUHTOR:
M.Y. Ahmad Fuad*, J. Mustafah and M.S. Mansor, Z.A. Mohd Ishak and A.K. Mohd Omar
19943/14/2017 12:12 PM1/18/2018 7:34 AM
rice_husk_ash_and_oil_palm_as_fillers_in_polypropylene_filler_content_determination_by_thermogravimetric_analysis.pdfRICE HUSK ASH AND OIL PALM AS FILLERS IN POLYPROPYLENE: FILLER CONTENT DETERMINATION BY THERMOGRAVIMETRIC ANALYSIS
  
ABSTRACT:
The use of three types of agricultural by-products as fillers in polypropylene has been investigated.  The first two were derived from burnt rice husk ash (RHA) while the third, a wood-based filler, was processed from oil palm trunk. One important characterization of the composites involves the checking for the actual filler content and filler distribution within the matrix. An analytical technique is  described here  for computation of the  filler content in  the  composites based on simple expression derived from  thermogravimetric analysis. For filler  with volatiles such as the  black RHA, the  derived expression is p, = 106(m/m0)  and for  easily burnt fillers  (wood-based),  the  expression is  p, = 160 (mime). The technique has shown good agreement (and consistency) between analysed and actual filler  contents with. a uniform filler distribution in  the  polypropylene matrix.

KEYWORDS: Polypropylene, rice husk ash (RHA), oil palm wood flour (OPWF), composite,
compounding, thermogravimetric analysis, filler content.

AUTHOR:
M.Y. Ahmad Fuad*, M.J. Zaini, J. Mustafah Z.A. Mohd Ishak and A.K. Mohd Omar
19943/14/2017 12:12 PM1/18/2018 7:33 AM
separation_by_selective_adsorption_preparative_liquid_chromatography.pdfSEPARATION BY SELECTIVE ADSORPTION: PREPARATIVE LIQUID CHROMATOGRAPHY
  
ABSTRACT:
An investigation to separate methyl isostearate from a mixture containing methyl esters and methyl isostearates using the isothermal liquid phase selective adsoption technique proved to be successful. The technique may provide the impetus for use ir simulated counter current technology. This particular investigation utilized the method of preparative liquid chromatography using several desorbent materials and separation conditions (temperature and sampling time). The maximum percentage composition of methyl isostearate separated was 81.1 %. This value was obtained using n-heptane + 1 % acetic acid as desorbents at 30°C. The solute desorption rates were found to be influened by both temperature and the percentage of the acetic acid or ethyl acetate added to n-heptane as desorbents.

AUTHOR:
Wan Mohtar Wan Vusoff, Che Husna Azhar and D. Lonchamp
19943/14/2017 12:13 PM1/18/2018 7:33 AM