5-catenadi-(phosphazene) (t-BuP4) was studied at room temperature.The structure and properties of the polymers have been characterized by nuclear magnetic resonance spectroscopy (NMR)
Flourier transform infrared spectroscopy (FTIR)
gel permeation chromatography (GPC)
differential scanning calorimetry (DSC) and themogravimetric analysis (TGA).The results showed that t-BuP4 displays high catalytic activity for the copolymerization of AMA with MMA
resulting linear copolymers with pendent allyl groups at back chains.Both the conversions of AMA and MMA could reach over 90% without considering the risk of gelation or crosslinking.NMR and FTIR results indicated that AMA incorporated into the copolymers by the reactions of methacrylate double bonds but not allyl groups.No cross-linking or cyclization reactions were observed during this polymerization system
which might be because the active centers catalyzed by t-BuP4 were not strong enough for the initiation of ally groups.The amount of pendant double bonds in the copolymers could be adjusted by changing AMA/MMA feed ratio.GPC results showed that the resultant copolymers have narrow polydispersity and good molecular weight control.TGA and DSC results showed that the decomposition temperatures for copolymers increased with the increasing of AMA/MMA feed ratio
but the glass transition temperatures (Tg) were changed oppositely.
关键词
悬垂双键甲基丙烯酸烯丙酯甲基丙烯酸甲酯
Keywords
Pendent allyl groupAllyl methacrylateMethyl methacrylate