8 Oleochemistry Products
241
reaction with water, in the presence of acid catalysts; (iii) ozonolysis followed by
hydrogenation. The polyol derived polyurethanes properties depend on the number,
distribution, site of hydroxyls, that can cause problems in the reproducibility of the
sample and imperfections, leading to a low resistance to stress and low flexibility of
the polyols [8].
Polyurethanes: synthesized by polyaddition reaction between (di-or poly-) isocyanates and (di- or polyhydric) alcohols. Polyurethanes are characterized by excellent resistance to corrosion, abrasion, water and chemical resistance and high durability. VO amide diols and polyols are used as raw materials for polyurethanes synthesis. The firsts are obtained by base-catalyzed amidation of virgin VO, the latter by chemical reactions involving ester groups or unsaturation of VO backbone.
These products are characterized by the presence of functional groups such as amide,
acrylics, ester, vinyl, double bonds and others [6, 7], which presence improves several properties, such as adhesion, flexibility, impact resistance and scratch hardness.
Moreover, they show curing or drying at ambient temperatures. Curing procedure
involves three steps: (i) solvent evaporation; (ii) chemical reaction of free isocyanates
of polyurethanes with moisture; (iii) auto-oxidative crosslinking.
Antimicrobial polyurethane coatings were prepared using Linseed polyol
nanocomposite [LMPOL]. Nanocomposite is prepared in situ with Linseed polyol
[LP] matrix as organic and Copper acetate as an inorganic constituent by ‘solventless
one-pot’ chemical reaction. The presence of characteristic absorption bands in FTIR
spectra confirmed the formation of LMPOL. TEM analysis showed the presence of
nano-sized metal oxide in LMPOL. LMPOL showed good antibacterial behaviour
against E. coli and S. aureus. The interactions between LMPOL and bacterial surfaces lead to good antibacterial efficacy, suggesting membrane disruption based cell
death [198].
Bio-based thermoset polyurethane (PU) coatings comprised of polyesteramides
were prepared from Gossypium arboreum (cottonseed) plant oil as a renewable source
[142]. Oil was first converted into fatty amide that was transformed into a series
of polyesteramide polyols upon esterification with different dicarboxylic acids and
anhydride. Bio-based polyesteramide polyols were used to prepare thermoset PU by
treating with an aromatic diisocyanate. Coatings prepared using renewable source
based polyesteramides were with highly suitable for curing, mechanical/chemical
performances, alkali/acid resistance and hydrophobicity. Compared to conventional
PU coatings, the prepared coatings possess superior properties such as gloss, adhesion
and pencil hardness. Gossypium arboreum plant oil and dicarboxylic acids were
concluded to be newer eco-friendly raw materials for PU coatings and compared
with standard petro-based polyols [163].
New oils: a new class of synthesis VO. For example, Lesquerella and dehydrated
Lesquerella oils were studied for use in alkyd-type coatings, showing good performances in terms of drying time, flexibility and corrosion resistance. 9c,12,13 epoxyoctadecenoic acid (vernolic acid), derived from Euphorbia lagascae and Vernonia
galamensis, can act as a reactive diluent in many solvent and waterborne coatings.
Linseed oil based poly (ester urethane) metallohybrids [PEUMH] was prepared
from organic and inorganic precursors, respectively, in ‘one-pot, multi-step’ reaction.
241
reaction with water, in the presence of acid catalysts; (iii) ozonolysis followed by
hydrogenation. The polyol derived polyurethanes properties depend on the number,
distribution, site of hydroxyls, that can cause problems in the reproducibility of the
sample and imperfections, leading to a low resistance to stress and low flexibility of
the polyols [8].
Polyurethanes: synthesized by polyaddition reaction between (di-or poly-) isocyanates and (di- or polyhydric) alcohols. Polyurethanes are characterized by excellent resistance to corrosion, abrasion, water and chemical resistance and high durability. VO amide diols and polyols are used as raw materials for polyurethanes synthesis. The firsts are obtained by base-catalyzed amidation of virgin VO, the latter by chemical reactions involving ester groups or unsaturation of VO backbone.
These products are characterized by the presence of functional groups such as amide,
acrylics, ester, vinyl, double bonds and others [6, 7], which presence improves several properties, such as adhesion, flexibility, impact resistance and scratch hardness.
Moreover, they show curing or drying at ambient temperatures. Curing procedure
involves three steps: (i) solvent evaporation; (ii) chemical reaction of free isocyanates
of polyurethanes with moisture; (iii) auto-oxidative crosslinking.
Antimicrobial polyurethane coatings were prepared using Linseed polyol
nanocomposite [LMPOL]. Nanocomposite is prepared in situ with Linseed polyol
[LP] matrix as organic and Copper acetate as an inorganic constituent by ‘solventless
one-pot’ chemical reaction. The presence of characteristic absorption bands in FTIR
spectra confirmed the formation of LMPOL. TEM analysis showed the presence of
nano-sized metal oxide in LMPOL. LMPOL showed good antibacterial behaviour
against E. coli and S. aureus. The interactions between LMPOL and bacterial surfaces lead to good antibacterial efficacy, suggesting membrane disruption based cell
death [198].
Bio-based thermoset polyurethane (PU) coatings comprised of polyesteramides
were prepared from Gossypium arboreum (cottonseed) plant oil as a renewable source
[142]. Oil was first converted into fatty amide that was transformed into a series
of polyesteramide polyols upon esterification with different dicarboxylic acids and
anhydride. Bio-based polyesteramide polyols were used to prepare thermoset PU by
treating with an aromatic diisocyanate. Coatings prepared using renewable source
based polyesteramides were with highly suitable for curing, mechanical/chemical
performances, alkali/acid resistance and hydrophobicity. Compared to conventional
PU coatings, the prepared coatings possess superior properties such as gloss, adhesion
and pencil hardness. Gossypium arboreum plant oil and dicarboxylic acids were
concluded to be newer eco-friendly raw materials for PU coatings and compared
with standard petro-based polyols [163].
New oils: a new class of synthesis VO. For example, Lesquerella and dehydrated
Lesquerella oils were studied for use in alkyd-type coatings, showing good performances in terms of drying time, flexibility and corrosion resistance. 9c,12,13 epoxyoctadecenoic acid (vernolic acid), derived from Euphorbia lagascae and Vernonia
galamensis, can act as a reactive diluent in many solvent and waterborne coatings.
Linseed oil based poly (ester urethane) metallohybrids [PEUMH] was prepared
from organic and inorganic precursors, respectively, in ‘one-pot, multi-step’ reaction.