title: A novel benzoxazine/cyanate ester blend with sea-island phase structures.
abstract: A novel cardanol-based benzoxazine (C-BOZ)/bisphenol A dicyanate ester (BADCy) blend with sea-island phase structures was successfully prepared via reaction-induced phase separation. The introduction of a long-chain alkyl group on the benzene ring significantly enhanced the thermodynamic differences between C-BOZ and BADCy. With the increase of the BADCy content, the Flory-Huggins interaction parameter (χ) of the blend decreased. By adjusting the ratio of the two components, sea-island phase separations were observed in C-BOZ/BADCy blends during the curing process. The dispersed phase was a C-BOZ rich phase, while the matrix was the crosslinked network composed of triazine rings and ring-opened C-BOZ. On the DMA curves of 9/1, 8/2 and 7/3 cured blends, there were two distinct Tgs. But with the increase of the BADCy content, the extent of phase separation was reduced. When the ratio reached 5/5, there was only one Tg because the viscosity of the blend was too high for phase separation to occur.
authors.affiliation: Key Laboratory of Catalysis Science and Technology of Chongqing Education Commission, College of Environment and Biological Engineering, Chongqing Technology and Business University, Chongqing, 400067, P. R. China.
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Li
authors.forename: Xiaoyong
authors.initials: X
authors.lastname: Luo
authors.forename: Yi
authors.initials: Y
authors.lastname: Gu