Emerging Science Journal
|
Vol. 3, No. 2
Page | 102
dimensional cross-linked harden structure. The load-bearing capacity of plastics improved by reinforced with fibers.
This could be a better replacement for the traditional building materials like wood
and steel due to high strength,
chemical resistant withstand ability properties [4, 5]. The phenol-formaldehyde (PF) resol formed by crosslinking of
phenol and formaldehyde in the presence of alkali. It could be used extensively
due to their low cost,
comfort of
processing, enduring thermal and chemical resistance, greater dimensional stability and viscosity. Phenolic resins which
having low molecular weight are used in laminating paper to reduce the water adsorption. High molecular weight resins
commonly used in ply wood glue, thermal insulators and moldings [6].
PF resin with improved thermal stability could be prepared by introducing flame retardant element like bromine to
the polymerization reaction [7]. Recent research result shown that Boron modified phenolic resin had lower degree of
polymerization than virgin PF in laboratory. The curing kinetics and molecular structure varies depending on the type
of boron modifier [8]. The recent growth in industrialization leads to increase petrochemical consumptions. This extreme
usage will enhance environmental pollution. So that ecofriendly alternatives for the petrochemicals are essential [7]. PF
resins used in wood industrials as their excellent water
resistance and heat resistance, [9]
but their usage limited by
higher cost production and their toxicity. Hence modifications with biomass are essential to overcome these limitations.
Nowadays, polymers from renewable resources have the great attention as
their environment control, sustainability and
low cost for manufacture.
Acacia
species are found to be a most specific species in tropical region. They are used in wood industries and the
large amount of saw dust threw as waste. Saw dust is the good source of lignin [9]. Hence, the use of
Acacia
wood
powder could be used as a raw material of lignin with the eco-friendly concern. [10, 11] Recent survey shows that the
aromatic property of lignin and its ability to participate in radical mediated cross
linking and ability to form
thermoplastic, make it attractive as a modifier to polymers to enhance physico-chemical properties [12-14].
In this course work, saw dust was used as a raw material for lignin extraction. Extracted alkali lignin was used to
prepare P-F resin. Thermal stability and the desired properties were characterized for the modified resins and moreover,
the cadmium ion adsorption capacity also investigated for the novel, extracted lignin and bio based resin.
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