| Abstract: | 4-Vinylbenzophenone anile is prepared from 4-vinylbenzophenone and aniline. In contrast to 4-vinylbenzophenone, it can be polymerized up to high conversions without crosslinking. From IR-spectroscopic analysis of the copolymers prepared radically at 60°C from styrene and 4-vinylbenzophenone anile, the following copolymerization reactivity ratios result: r1 = 1.88 ± 0.08 (4-vinylbenzophenone anile) and r2 = 0.36 ± 0.02 (styrene). Vinyl-α.α-diphenylethylene is obtained from methylmagnesium. iodide and 4-vinybenzophenone. Polymerization as well as copolymerization with styrene takes place not only via the vinyl group but also via the vinylidene group ; the rather low-molecular polymers which are formed still contain free vinyl groups. 4-Vinyl-4′-dimethylaminoazobenzene (prepared by diazotation of 4-aminostyrene and subsequent coupling with dimethyl aniline) does not undergo radical polymerization; it does, however, copolymerize with styrene. In this case, the rate of polymerization increases with decreasing content of 4-vinyl-4′-dimethylaminoazobenzene. The copolymerization reactivity ratios of this system can hence only be approximated. 4-Vinyltriaryl carbinols can be prepared in yields of 50 to 70 % from 4-vinyl-phenylmagnesium chloride and aryl ketones. 4-Vinyl-4′-phenyltriphenyl carbinol and 4-vinyl-4′.4″-diphenyltriphenyl carbinol can be polymerized radically in bulk as well as in benzene solution. Insoluble, completely cross-linked polymers are formed in bulk polymerization. In benzene solution at low conversions, soluble polymers are obtained with degrees of polymerization of 300 to 350. Dilatometric measurements show that the polymerization rates of the 4-vinyltriarylcarbinols are substantially greater than that of styrene. The 4-vinyltriarylmethyl chlorides, which are accessible via the corresponding 4-vinyl-triaryl carbinols with acetyl chloride, can be neither homopolymerized nor copolymerized with styrene since the triarylmethyl chloride groups inhibit radical polymerization. |
