Synthesis of novel poly(vinyl ether)s containing the oxybenzylidenemalononitrile group as a nonlinear optical chromophore, and their electro‐optic properties

Abstract

2,4‐Di‐(2′,2′‐dicyanovinyl)‐1‐(2′‐vinyloxyethoxy)benzene and 2,4‐di‐(2′‐carbomethoxy‐2′‐cyanovinyl)‐1‐(2′‐vinyloxyethoxy)benzene were prepared by condensation of 4‐(2′‐vinyloxyethoxy)isophthaldehyde with malononitrile and methyl cyanoacetate, respectively. The two vinyl monomers were polymerized with boron trifluoride etherate as a cationic initiator to yield poly(vinyl ether)s containing two oxybenzylidenemalononitrile and oxybenzylidenecyanoacetate groups, which are effective chromophores for second‐order nonlinear optical applications. These polymers were soluble in common organic solvents such as acetone and dimethyl sulforide. They showed thermal stabilities up to 300 °C from thermogravimetric analysis (TGA), with differential scanning calorimeter (DSC) thermograms giving Tg values in the range 73–87 °C. The second harmonic generation (SHG) coefficients (d33) of poled polymer films were around 1.8 × 10−9 esu, and these polymers showed good long‐term thermal stability for 60 days at room temperature, which is acceptable for nonlinear optical (NLO) device applications. Copyright © 2004 Society of Chemical Industry

Synthesis and optical properties of a crosslinkable polymer system containing tricyanofuran‐based chromophores with excellent electro‐optic activity and thermal stability

“…In the work reported in this article, we used the reaction between 2,4‐toluenediisocyanate (TDI) and hydroxyl groups as the crosslinking reaction to prepare a new crosslinkable NLO polymer with side‐chains 15, 16. Both uncrosslinked copolymers, composed of methyl methacrylate (MMA), 2‐hydroxyethyl methacrylate (HEMA) and NLO chromophores, and the corresponding crosslinked systems were prepared, characterized and discussed.…”