Allylic monomers as reactive plasticizers of polyphenylene oxide. Part I: Uncured systems

The effect of various diallyl (diallyl ortho phthalate, diallyl terephthalate and diethylene glycol diallyl carbonate) and triallyl monomers (triallyl cyanurate and triallyl isocyanurate) on the processability of polyphenylene oxide (PPO) was studied. The solubility parameters of the monomers indicated that diallyl orthophalate, dially terephthalate and triallyl cyanurate should be miscible with PPO suggesting their applicability as reactive plasticizers to improve the processability of PPO. Rheological studies of 60:40 wt:wt PPO:allylic blends indicate that the addition of 40 wt% of allylic monomers significantly improved processability – blends of 60PPO:40DEGDAC indicates the highest viscosity and the highest Tg. Rheological studies and dynamic mechanical analysis on various PPO/DAOP blends show that the increasing amounts of DAOP progressively decreases the viscosity and Tg of the blends. Phase separation at room temperature was observed by visual opacity, cloud point studies and DMTA in PPO:DAOP blends with less than 60 wt% PPO but at elevated temperatures the blends were miscible.

Figure optionsDownload as PowerPoint slideHighlights
► We have examined the applicability of allylic monomers as reactive plasticizers for PPO.
► Theoretical calculations of the solubility parameter of DAOP, DATO and TAC suggesting miscibility with PPO.
► Addition of 40 wt% of allylic monomers significantly improved the processibility of PPO.
► Dynamic mechanical studies of PPO blends with DAOP suggested miscibility of most of the uncured blends.
► Viscosity and Tg reduce continuously decrease with increasing DAOP content.