Synthesis And Application Of Light Stability Inorganic/organic Composite Particles

HALS(Hindered Amine Light Stabilizer) is one of capture-agents for living radicals. It can be used in general materials such as plastic, rubber, film and coating. At present, there are many problems such as loss from material/bad compatibility with polymer/a mass of content when using HALS with low molecular weight. Hence HALS with high molecular weight was phased in overseas. However, the process for macromolecule was very complicated. With the development of polymer for outdoors, HALS would make the cost of product higher. In this paper, the light stability composite particles having hindered amine structure were prepared in order to obtain granular HALS with high molecular weight. The properties of the composite particle were investigated and their blends with polymer materials were studied.At first, the silica particles were treated by the silane coupling agent having two amino groups (DB792). When the content of DB792 was 10% the result is optimal. The light stability composite particles were synthesized by the resulting silica particles having amino groups reacting with E-44 or MDI in a liquid/solid bi-phase system. IR showed that HALS radical had been grafted on the surface of the silica. After the analysis of amphiphilic/UV-shielding/heat stability for these particles, the data indicated that the products could satisfy the particle dispersing and molecule increasing without affecting the light stability of HALS. At the same time, two reaction systems were contrasted in order to find out the industrialized way.At last, the composite particles were added into the E-44 epoxy to form the composite material. The test of the mechanical properties showed that the properties were improved. The best properties would be obtained at the 2wt% of composite particles in the material. SEM and rigidity test explained that the particles could transfer to the surface of the material equably. Hence HALS can protect the material on surface. The natural aging experiment and mass-lostanalysing found that the antioxidant ability of the samples which contained the particles was increased largely. When composite particles content was 2wt%~3wt% , the antioxidant would work fully. In this point, the content of HALS was only about 0.04wt %. All these acquired prospective purposes.This paper provided a new way to realize macromolecule of HALS. It increased the efficiency and decreased the dosage in practicality. The production would make a progress in the field of surface modification for material.