苯乙烯-丙烯酸共聚纳米微球的制备及表征

Preparation and Characterization of Styrene-acrylic Acid Copolymer Nanospheres

以苯乙烯为单体，丙烯酸为功能单体，采用细乳液聚合法合成了苯乙烯一丙烯酸共聚纳米微球，采用zeta电位及激光粒度仪、透射电镜（TEM）、傅立叶变换红外光谱仪（FFIR）、热重分析仪（TG）、电导率仪对微球的粒径、形态结构、热性能、表面羧基含量等进行了表征。结果表明，微球粒径范围在50—70nm，随着丙烯酸的加入量增多，羧基红外特征峰面积增大；微球粒径随之变小；表面电荷密度增大；产物的热重分析曲线也体现出了一定的聚丙烯酸的热分解特征。这些结果说明聚苯乙烯微球表面成功带上了羧基，并可以通过控制单体比例调节其表面的羧基含量。

The nanospheres were prepared through miniemulsion polymerization with styrene as the monomer and acrylic acid as the functional monomer. Zeta potential and laser particle size instrument, transmission electron microscopy （TEM）, Fourier transform near infrared spectrometer （FTIR）, thermogravimetric analyzer （TG） and conductivity meter were used to characterize the particle size, morphology and structure, carboxyl content, thermal properties of the nanospheres. The results show that particle sizes range from 50 nm to 70 nm. With the increase of the addition amount of acrylic acid, the area of infrared characteristic peak increases, the particle size becomes smaller. The TGA curves also reflect the characteristics of the thermal deeomposition of polyacrylic acid. These results indicate that carhoxyl was successfully synthesized in polystyrene nanospheres, and the carboxyl content can be adjusted by controlling the monomer ratios.