RAFT法在纳米SiO_2表面接枝PBA及其对POM的改性研究

采用可逆加成-断裂链转移(RAFT)聚合法在纳米二氧化硅(SiO2)表面接枝聚丙烯酸丁酯(PBA),并采用透射电镜(TEM)、广角X射线衍射(WAXD)、差示扫描量热仪(DSC)及热重分析仪(TGA)等手段研究纳米SiO2及SiO2-PBA复合粒子的添加对聚甲醛(POM)结晶性能及热稳定性的影响.结果表明:用RAFT聚合方法有少量的PBA接枝于纳米SiO2表面;纳米SiO2及SiO2-PBA复合粒子的添加不改变聚甲醛的晶型;粒子的添加使用POM结晶温度、熔点和结晶度升高;且粒子的添加均使POM热稳定性提高.

Studies on grafting PBA onto surface of nano-silicon dioxide via RAFT reaction and modification of POM

In this paper,poly(butyl acrylate)(PBA) was grafted onto the suface of nano silicon dioxide(SiO_2) particles through Reversible addition-fragmentation chain transfered(RAFT) polymerization.Moreover,the effects of nano-SiO_2 particles and nano SiO_2-PBA composited particles on the crystallization behaviors and thermal stability of polyoxymethylene(POM) were studied by means of transmission electron microscope(TEM),wide-angle X-rays diffraction(WAXD),differential scanning calorimetry(DSC) and thermogravimetric analyzer(TGA).The results showed that PBA could be grafted on to the surface of nano-SiO_2through RAFT Reaction.Moreover,nano-SiO_2particles and nano SiO_2-PBA composited particles could not change the crystal type of POM,in comparison with nano SiO_2 particles,the heterogeneous nucleus effect of nano SiO_2-PBA composited particles was more obvious.Both nano SiO_2 particles and nano SiO_2-PBA composited particles could improve crystallization temperature,crystallinity and melting point of POM.In addition,in comparison with nano SiO_2 particles,nano SiO_2-PBA composited particles could improve the thermal stability of POM more obviously.