预辐照聚丙烯悬浮接枝聚苯乙烯的制备及结构性能

Preparation,Structure and Properties of Pre-Irradiation Polypropylene Grafted Polystyrene in Suapension

通过预辐照和悬浮接枝技术制备聚丙烯接枝聚苯乙烯(PP-g-PS)。利用红外光谱、核磁共振、X射线衍射、差示扫描量热分析、旋转流变仪及高压击穿实验对PP-g-PS的结构和性能进行了表征。结果表明,PP-g-PS的FT-IR在1493cm^(-1),1601 cm^(-1)和3027 cm^(-1)处出现了新的吸收峰,其中1601 cm^(-1)和3027 cm^(-1)分别为PS苯环上C=C和C-H的特征吸收峰;1H-NMR在1.2,1.4和2.0位置处出现新的化学位移峰,在δ7.1和7.2处出现2组峰,这是PS苯环上氢的化学位移,证明PS已接枝到PP的大分子链上。与PP相比,PP-g-PS的熔融温度和结晶度降低,结晶温度升高;随接枝率增大,PP-g-PS的结晶温度升高;PP-g-PS的耐电压击穿性能好,其击穿场强可达PP的1.4倍。

Polypropylene grafted polystyrene（ PPg-PS） was prepared by pre-irradiation suspension grafting. The structure and properties of PP-g-PS were investigared by FT-IR,1H-NMR,WAXD,DSC,GPC,rotational rheometer and breakdown voltage test. The FT-IR spectra of PP-g-PS show some new peaks at 3027 cm^-1,1601 cm^-1 and 1493cm^-1,which are attributed to C- H bond and C = C double bond of benzene ring. The1H-NMR spectra of PP-g-PS show new chemical shift peaks at 2. 0,1. 4,1. 2,7. 2 and 7. 1,which are attributed to the H from benzene ring in PS. These results indicate that PS is successfully grafted onto PP molecular chains. The melting temperature and molten enthalpy of PP-g-PS are lower than those of PP. With increasing of the degree of grafting of PP-g-PS,the crystallization temperature increases and crystallization enthalpy gradually decreases. Electrical property results reveal that the breakdown voltage value of PP-g-PS is 1. 4 times higher than that of pure PP.