Research On The Preparation Of Polymetic N-alkoxy Hindered Amines

It’s well known that the strically hindered amine are widely used as light stabilizers or flame retardants for polymer materials,due to their excellent light and heat stabilization efficiency.However,the common strically hindered amine compounds are not useful in applications where exposure to acids takes place.In order to dissolve this problem,the N-alkoxy hindered amines were developed to reduce the basicity of the hindered amine compounds.At the same time,to enhence the compatibility of polymer materials and hindered amine additive,the polymetic hindered amine with high molecular weight were developed.The synthesis of N-alkoxy hindered amine from 2,2,6,6-tetramethy-4-one-piperidine were first researched in this thesis.Using hydrogen peroxide as oxidant,1-oxyl-2,2,6,6-tetramethy-4-one-piperidine,a nitronyl radical compound,was prepared from 2,2,6,6-tetramethy-4-one-piperidine.Then,the 1-propoxy-2,2,6,6-4-one-piperidine,an important intermediate of N-alkoxy hindered amine compounds,was synthesized by 1-oxyl-2,2,6,6-tetramethy-4-one-piperidine and butanal,catalyzed by CuCl through a radical reaction process.N,N’-Bis(1-propoxy2,2,6,6-tetramethylpiperidin-4-yl)hexan-1,6-diamine,a key intermediate of polymetic N-alkoxyl hindered amine,were prepared through a directive amination of 1-propoxy-2,2,6,6-4-one-piperidine.Catalyzed skeletal copper,the reaction was carried out in autoclave under a hydrogen pressure of 3.5 MPa and the goal compound was obatined in a yield over 90%.The cycle performance of the skeletal copper catalyst in this reaction was also been studied,and results showed nice cycle performance in pilot scale.The synthesis technology of a polymetic N-alkoxy hinered amine compound 371 from polymetic hindered mine compound 2020,has also been researched in this thesis.The 2020 was oxidized by hydrogen peroxide in xylene,a polymetic racial compound was obtained.Using butanal as the N-alkyoxy reagent reacted with the polymetic racial,a famous polymetichinered amine compound 371 was synthesized as goal product.