Compounds for Grafting

One way to obtain permanent additives is to covalently bond them to the polymeric matrix through a chemical reaction. Among possible reactions, one option is to have photo-reactive moieties in the additive molecule so that, by exposition to visible and/or ultraviolet light, either from an artificial source or from solar irradiation, the molecule reacts with the polymeric substrate. As a consequence, the additive are grafted to the polymer so that the effect imparted by the former is permanent. Several examples of photo-reactive additives are reported in the literature (6). 

This compound is an example of a graftable functional monomer having in addition a hydrophilic residue. Composition may im-dergo photo-grafting via exposition under natural light or artificial suitable UV source. Responsible for photo-grafting is the cinnamic moiety in the compound. 

By combining opportunely migration of antifogging agents to the surface of the polymer substrate with the reaction of a photo-sensible moiety contained in the antifogging additive itself, it is possible to have the reaction induced by light when most or at least part of the 

Piccinelli, M. Vitali, A. Landuzzi, G. Da Roit, P. Carrozza, M. Grob, and N. Lelli, Permanent surface modifiers, US Patent 7 408 077, assigned to Ciba Specialty Chemicals Corp. (Tarrytown, NY), August 5, 2008. 

Zweifel, ed.. Plastics Additives Handbook, Hanser Publishers, Munich, 5th edition, 2001. 

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