聚酯用金红石型二氧化钛浆料的分散性能研究

Study on dispersion of rutile titanium dioxide slurry for polyester

研究了聚对苯二甲酸乙二醇酯(PET)用金红石型二氧化钛(TiO_2)粉体在乙二醇(EG)中的分散性和稳定性,考察了pH值、分散剂六偏磷酸钠(SHMP)用量和研磨时间对金红石型TiO_2浆料分散性能的影响以及在原位聚合法制PET中的应用情况。结果表明:在pH值为6.5~10.0时,金红石型TiO_2水溶液的Zeta电位绝对值小于30 mV,当在其中加入质量分数为1.6%(相对金红石型TiO_2)的SHMP时,其Zeta电位绝对值为50.1 mV;质量分数为50%的金红石型TiO_2-EG浆料(SHMP质量分数为1.0%)研磨时间为20~60 min时,TiO_2在浆料中的分散效果最好;金红石型TiO_2-EG浆料研磨分散后放置48 h,TiO_2粒子粒径分布稍有变宽,没有出现明显的团聚;将没有静置的金红石型TiO_2-EG浆料应用于PET的原位聚合中,所制得的半消光PET切片中的TiO_2粒子分散良好,直径小于1 000 nm,没有出现明显的二次团聚现象。

The dispersion and stability of rutile titanium dioxide（ TiO2） particle for polyethylene terephthalate（ PET） were studied in ethylene glycol（ EG）. The effects of the pH value,dosage of sodium hexametaphosphate（ SHMP） dispersant and treating time on the dispersion of rutile TiO2 slurry were investigated,as was its application performance in PET prepared via insitu polymerization. The results showed that the absolute value of zeta potential of the rutile TiO2 solution was less than 30 mV when the pH value was 6. 5-10. 0; the absolute value of zeta potential was 50. 1 mV as the mass fraction of SHMP was 1. 6%based on rutile TiO2; the dispersion of TiO2 slurry was optimized when the mass fraction of TiO2 particle was 50% in TiO2-EG suspension,the mass fraction of SHMP was 1. 0% based on TiO2 and the treating time was 20-60 min; the TiO2 particle size distribution was slightly widened but with no obvious agglomeration while the rutile TiO2-EG slurry standing for 48 h after treatment; the obtained semi-dull PET chip had the favorable dispersion of TiO2 particle below 1 000 nm in the diameter with no obvious secondary agglomeration when the rutile TiO2-EG slurry suspension without standing was applied in the in-situ polymerization of PET.