研究了在二流体喷雾干燥器中醋酸乙烯-乙烯(VAE)聚合物乳液(含保护胶体)的液滴大小、粉体粒径大小及这两者之间的关系。考察了压缩空气与料液的质量流量比、进风温度、进风流量和乳液黏度对粉体粒径的影响。分别用激光多普勒动态分析仪、激光粒径分析仪和扫描电镜对VAE聚合物乳液滴径、粉体的粒径和颗粒形貌进行了表征。研究表明：当进风温度为120~145℃、进风流量为220~302.5 m3⋅h−1时，喷雾干燥得到的粉体，其粒径与进风温度和进风流量几乎无关；当压缩空气与料液的质量流量比为1~16时，粉体粒径随雾化比的增大而减小，并且与滴径成线性关系；当VAE聚合物乳液的黏度为2~140 mPa⋅s，其他操作条件不变时，滴径与粉体粒径之间也满足这种线性关系。% The particle and droplet sizes of vinyl acetate-ethylene (VAE) polymer latices containing protective colloids and the relationship between them in a two-fluid spray dryer were studied in this paper. Effects of the mass flow ratio of the compressed air to liquid feed (ALR), inlet air temperature, inlet air flow rate and viscosity of VAE polymer latices on the particle sizes were investigated. Droplet sizes, particle sizes and surface morphologies were characterized by means of Laser Doppler Dynamic Analyzer, Laser Particle Size Analyzer and Scanning Electron Microscopy, respectively. It was demonstrated that the mean sizes of the spray-dried particles are almost irrelevant to both the inlet air temperature in the ranges of 120~145℃ and the inlet air flow rate in the range of 220~302.5 m3⋅h−1. However, the mean sizes of the spray-dried particles decrease with the increase in ALR in the range of 1~16 and have linear relation to the mean sizes of the droplets. Moreover, this relation is also suitable to the relationship between the mean sizes of the spray-dried particles and that of the droplets derived from the VAE polymer latices with the viscosities of 2~140 mPa⋅s without changes in other operational variables.
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