TY - JOUR
T1 - Seed oils rich in linolenic acid as renewable feedstock for environment-friendly crosslinkers in powder coatings
AU - Overeem, A.
AU - Buisman, G.J.H.
AU - Derksen, J.T.P.
AU - Cuperus, F.P.
AU - Molhoek, L.
AU - Grisnich, W.
AU - Goemans, C.
PY - 1999
Y1 - 1999
N2 - In the work described, seed oils rich in linolenic acid were used for the synthesis of aliphatic oxiranes. The oils studied were linseed (Linum usitatissimum) oil, Canadian linseed oil and the oil of Lallemantia iberica. The oils contained 54.1, 60.2 and 68.0% of linolenic acid, respectively, and showed high theoretical iodine values of 211,226 and 236 g/hg. Unsaturations in the oils were used to introduce epoxides by epoxidation with in situ generated peroxyacetic acid. The epoxidized oils, showing high percentages of oxirane oxygen (9.4, 10.0 and 10.7%, were applied as crosslinkers in powder-coating formulations. The major advantage of these types of crosslinkers is that they are neither toxic nor mutagenic, in contrast with the widely applied synthetic triglycidyl isocyanurate (TGIC) crosslinkers. However, two potential problems exist when aliphatic oxiranes are compared with conventional TGIC systems. A decrease in glass transition temperature (T(g)) of the powder formulation and a higher degree of yellowing of the coating are often observed. In this paper the effects of using oils containing high linolenic acid contents on the yellowing of the coating and the T(g) of the powder, are studied. It appeared that aliphatic oxiranes are suitable as environment-friendly crosslinkers in powder-coating systems.
AB - In the work described, seed oils rich in linolenic acid were used for the synthesis of aliphatic oxiranes. The oils studied were linseed (Linum usitatissimum) oil, Canadian linseed oil and the oil of Lallemantia iberica. The oils contained 54.1, 60.2 and 68.0% of linolenic acid, respectively, and showed high theoretical iodine values of 211,226 and 236 g/hg. Unsaturations in the oils were used to introduce epoxides by epoxidation with in situ generated peroxyacetic acid. The epoxidized oils, showing high percentages of oxirane oxygen (9.4, 10.0 and 10.7%, were applied as crosslinkers in powder-coating formulations. The major advantage of these types of crosslinkers is that they are neither toxic nor mutagenic, in contrast with the widely applied synthetic triglycidyl isocyanurate (TGIC) crosslinkers. However, two potential problems exist when aliphatic oxiranes are compared with conventional TGIC systems. A decrease in glass transition temperature (T(g)) of the powder formulation and a higher degree of yellowing of the coating are often observed. In this paper the effects of using oils containing high linolenic acid contents on the yellowing of the coating and the T(g) of the powder, are studied. It appeared that aliphatic oxiranes are suitable as environment-friendly crosslinkers in powder-coating systems.
KW - (Canadian) linseed oil
KW - Crosslinker
KW - Epoxidation
KW - Lallemantia iberica
KW - Linolenic acid
KW - Powder coating
U2 - 10.1016/S0926-6690(99)00018-7
DO - 10.1016/S0926-6690(99)00018-7
M3 - Article
SN - 0926-6690
VL - 10
SP - 157
EP - 165
JO - Industrial Crops and Products
JF - Industrial Crops and Products
IS - 3
ER -
