Modification Of Rapeseed Oil And Its Leather Fatliquor

China has become an important center of leather-making and trading. In the leather-making process, leather chemicals are needed, in which fat-liquoring agent is one of the most important chemical materials. The feeling and style of leathers are always determined by fatliquoring agents to some extent. It may even be said that fat-liquoring agent is one of the most important factors restricting the development of leather industry. At present, both in the qualities and performances, the domestic fatliquoring agents can not meet the demands of leather industry. The preparation of fat-liquoring agent with high qualities and performances is imperative.The principle of molecule design was applied in this paper. First, in order to introduce the hydroxyl groups and reduce the molecular weight of vegetable oil, the rapeseed oil was modified by transesterification. The modifying conditions were described as follows: the ratio of the rapeseed oil and carbinol was l:2.5(mol:mol), the catalyst dosage was 1.2% of rapeseed oil in weight, reaction temperature was 65°C, and reaction time was 3hr. Acetic acid was chosen as the active oxygen carrier, and a strong-acid ion exchange resin was chosen as the catalyst, the transesterification product was modified by epoxidation. The modifying conditions were described as follows: the catalyst dosage was 5.0%, the oxydol dosage was 40.0% and the reaction temperature was 55°C. Then the epoxidation product was modified by sulphitation, collagen and polyethylene glycol, respectively. The hydrophilic groups such as sulfonic groups, collagen chains and ether chains were introduced. The self-emulsifiable oil was prepared.For the improvement of the handfeeling of the fatliquored leathers, both amino silicone oil and beeswax were introduced, too. In order to weaken the cationic and keep the excellent properties of the flexibility, smoothness and the elasticity, the amino silicone oil was modified by acetic anhydride. And the modifying conditions were described as follows: modifying agent was 6.0% of amino silicone oil in weight, solvent was 55-65% of the amino silicone oil, reaction temperature was 50-55℃, and reaction time was 1.5h. The FTIR spectra were successfully applied to characterize the structure of the modified amino silicone oil. The beeswax was emulsified when the conditions were as follows: the composite emulsification agent dosage was 20.0% of beeswax in weight, emulsification temperature was 85℃and emulsification time was 60min. Then the above-mentioned products were compounded according to the following proportions: the rapeseed oil modified by collagen was 10.0 in weight, the sulphited rapeseed oil was 15.0 in weight, the hydroxide and ethoxyl rapeseed oil was 25.0 in weight, the composite emulsification agent was 15.0 in weight, the modified amino silicone oil was 2.5 in weight, the beeswax emulsion was 30.0 in weight, the vaseline was 2.5 in weight and the water was 40.0 in weight. Then a compound fatliquoring agent with high qualities was prepared. The fatliquoring experiments were conducted. The results indicated that the optimal fatliquoring conditions were as described as follows: the fatliquoring temperature was 60℃, the pH of neutralization was 6.5. The leathers fatliquored with it showed good fullness, softness, elasticity, greasy and silky feeling.