用中等气压空气中均匀介质阻挡放电(DBD)产生的低温等离子体对聚丙烯(PP)薄膜进行表面改性。通过接触角和表面能测量、扫描电子显微镜(SEM)和全反射傅里叶红外光谱(ATR-FTIR)等方法,研究了等离子体改性时间和功率密度对PP薄膜表面水接触角、表面能、表面粗糙度以及表面化学成分等的影响。结果表明:PP表面水接触角和表面能先是随处理时间增加分别下降和增加,然后达到饱和状态;当处理时间一定时,功率密度越大,接触角下降的越多,表面能上升的越多;增大DBD处理的功率密度,利用更少的处理时间就能得到同样的处理效果。表面样貌及化学成分分析表明,随功率密度的增大,处理后薄膜表面的粗糙度增加,表面引入的含氧基团增多。
The surfaces of polypropylene(PP) films were modified using non-thermal plasma generated by a homogeneous dielectric barrier discharge(DBD) in air at moderate pressure.The effects of modification time and power density on the water contact angle,surface energy,surface roughness and surface chemical composition of PP surface were studied by means of contact angle measurement,scanning electron microscopy(SEM) and attenuated total reflectance Fourier transform infrared spectroscopy(ATR-FTIR).Results show that the water contact angle and surface energy of PP films decreases and increases first,respectively with the increase of treatment time,and then reach a saturation state at a certain treatment time.When the treatment time is invariable,the larger the power density is,the lower is the contact angle and the higher is the surface energy.When the power density of DBD treatment increases,much shorter treatment time is enough for the same effect.SEM observations and FTIR analysis reveal that,the larger the power density is,and the higher are the surface roughness and oxygen-containing polar groups on the treated PP surface.