240
R. Tesser et al.
process was optimized and DMPA was reduced to a minimum amount. It was shown
that even at a lower content of emulsifier; stable dispersions and film formation are
possible. It is confirmed that the lower the content of the ionic emulsifier, the higher
is the chemical resistance and hydrophobicity. Regarding the dispersion stability
and particle size distribution, there was no influence on the amount of hydrophobic components observed. However, the visual appearance of the coating films is
improved with an increasing amount of DMPA used and even further improved
with low amounts of hydrophobic components. Fatty acid methyl esters were used
as monofunctional building blocks and require trifunctional building blocks to go
along with them. But rapeseed oil based fatty acid methyl esters provide further possibilities for modification. Ongoing investigations are focusing on modification at the
double bond and on the ester functionality. It is our objective to obtain new bifunctional monomers for polycondensation. As rapeseed fatty acid methyl ester contains
mainly oleic acid, it is easier to obtain bifunctional monomers than to use triglycerides or highly unsaturated fatty acids, which lead to highly functional monomers
and promote networks instead of polymer chains. In conclusion, fatty acid methyl
esters offer a great opportunity to increase bio-based raw material use in coatings
and to improve properties like chemical resistance and hydrophobicity at the same
time [166].
Epoxides: VO coatings characterized by the presence of oxirane groups in the
backbone. They can be either present in nature (i.e. Euphorbia and Cephalocroton species) or obtained by chemical reaction, the epoxidation reaction, described
in detail in the next sections of this chapter. These products show high flexibility
and good corrosion resistance against moisture and chemicals, due to their long
hydrophobic chains [197]. Epoxy coatings can be cured with curing agents, such as
acids, amines, amides and anhydrides. The formulation procedure can strongly affect
the final performances of the product: i.e. films obtained blending epoxy-VO with
polyvinyl chloride and polyvinyl alcohol shown high biodegradability [177], while
epoxy-VO blended with polymethylmethacrylate and polystyrene are used as corrosion protective coatings [4]. Epoxy acrylate oligomer (EA) was plasticized by adding
different plasticizers such as epoxidized soybean oil, glycerol and CO and cured by
electron beam (EB). Incorporation of CO in epoxy acrylate diluted by 1,6-hexanediol
diacrylate (HD) monomer improved the physical, chemical and mechanical properties of cured films than the other plasticizer. Sunflower-free fatty acid was epoxidized
in situ under well-established conditions. The epoxidized sunflower-free fatty acids
were subjected to react with aniline in sealed ampoules under an inert atmosphere at
140 °C. The produced adducts were added at different concentrations to the epoxy
acrylate coatings. It was found that addition of aniline adducts to epoxy acrylate
formula gives the best corrosion protection for carbon steel and compete for the
commercial corrosion inhibitor efficiency with the same concentration [91].
Polyols: long aliphatic chains with various functional groups, such as hydroxyls,
double bonds, active methylene groups and oxirane rings. They are present in nature
(i.e. ricinoleic and lesquerolic acids) and can be obtained following different pathways: (i) hydroformylation followed by VO catalytic hydrogenation; (ii) epoxidation
of VO unsaturation followed by catalytic hydrogenation or by oxirane ring-opening
R. Tesser et al.
process was optimized and DMPA was reduced to a minimum amount. It was shown
that even at a lower content of emulsifier; stable dispersions and film formation are
possible. It is confirmed that the lower the content of the ionic emulsifier, the higher
is the chemical resistance and hydrophobicity. Regarding the dispersion stability
and particle size distribution, there was no influence on the amount of hydrophobic components observed. However, the visual appearance of the coating films is
improved with an increasing amount of DMPA used and even further improved
with low amounts of hydrophobic components. Fatty acid methyl esters were used
as monofunctional building blocks and require trifunctional building blocks to go
along with them. But rapeseed oil based fatty acid methyl esters provide further possibilities for modification. Ongoing investigations are focusing on modification at the
double bond and on the ester functionality. It is our objective to obtain new bifunctional monomers for polycondensation. As rapeseed fatty acid methyl ester contains
mainly oleic acid, it is easier to obtain bifunctional monomers than to use triglycerides or highly unsaturated fatty acids, which lead to highly functional monomers
and promote networks instead of polymer chains. In conclusion, fatty acid methyl
esters offer a great opportunity to increase bio-based raw material use in coatings
and to improve properties like chemical resistance and hydrophobicity at the same
time [166].
Epoxides: VO coatings characterized by the presence of oxirane groups in the
backbone. They can be either present in nature (i.e. Euphorbia and Cephalocroton species) or obtained by chemical reaction, the epoxidation reaction, described
in detail in the next sections of this chapter. These products show high flexibility
and good corrosion resistance against moisture and chemicals, due to their long
hydrophobic chains [197]. Epoxy coatings can be cured with curing agents, such as
acids, amines, amides and anhydrides. The formulation procedure can strongly affect
the final performances of the product: i.e. films obtained blending epoxy-VO with
polyvinyl chloride and polyvinyl alcohol shown high biodegradability [177], while
epoxy-VO blended with polymethylmethacrylate and polystyrene are used as corrosion protective coatings [4]. Epoxy acrylate oligomer (EA) was plasticized by adding
different plasticizers such as epoxidized soybean oil, glycerol and CO and cured by
electron beam (EB). Incorporation of CO in epoxy acrylate diluted by 1,6-hexanediol
diacrylate (HD) monomer improved the physical, chemical and mechanical properties of cured films than the other plasticizer. Sunflower-free fatty acid was epoxidized
in situ under well-established conditions. The epoxidized sunflower-free fatty acids
were subjected to react with aniline in sealed ampoules under an inert atmosphere at
140 °C. The produced adducts were added at different concentrations to the epoxy
acrylate coatings. It was found that addition of aniline adducts to epoxy acrylate
formula gives the best corrosion protection for carbon steel and compete for the
commercial corrosion inhibitor efficiency with the same concentration [91].
Polyols: long aliphatic chains with various functional groups, such as hydroxyls,
double bonds, active methylene groups and oxirane rings. They are present in nature
(i.e. ricinoleic and lesquerolic acids) and can be obtained following different pathways: (i) hydroformylation followed by VO catalytic hydrogenation; (ii) epoxidation
of VO unsaturation followed by catalytic hydrogenation or by oxirane ring-opening