超分散稳定纳米PbS的非水原位构筑及摩擦学特性

Nonaqueous In-situ Synthesis and Tribological Properties of PbS Nanoparticles of Ultradispersion and Stabilization

设计并合成了油溶性铅盐和胺基类超分散剂，用非水滴定方法、电感耦合等离子体原子发射光谱、傅立叶红外光谱仪、凝胶渗透色谱仪对其进行了表征；在添加有油溶性铅盐和0．3％超分散剂的液体石蜡介质中，原位构筑了纳米PbS；对构筑的纳米PbS进行了72h连续普通离心试验和56h非连续高速离心试验，以考察其分散稳定性；用激光散射原位表征了纳米PbS的粒径及粒径分布；用环块试验机对纳米PbS作为润滑油添加剂的摩擦学性能进行了评价。结果表明：构筑的纳米PbS经普通离心试验和非连续高速离心试验均未出现两相分离现象，说明纳米PbS在液体石蜡中表现出超分散稳定性；纳米PbS粒子大小均匀、粒径分布窄；超分散稳定纳米PbS的存在，能显著降低油品的摩擦因数和磨损量，在试验选择的添加量（质量分数0．05％-0．3％）范围内，可使油品的承载能力提高1倍。

The oil-soluble lead salts and hyper-dispersion stabilizer were synthesized according to design performance. They were characterized with nonaqueous titrimetric analysis, infrared spectrum,inductive coupled plasma atomic emission spectrometrer and gel permeation chromatography. The PbS nanoparticles（n-PbS） were synthesized in-situ in liquid paraffin containing oil-soluble lead salt and hyper-dispersion stabilizer. The accelerated tests were used for evaluating the dispersion behaviors and dispersion stability of n-PbS in liquid paraffin by common speed centrifuge and high speed centrifuge. The diameter and diameter distribution of n-PbS in medium were observed through laser scattering method. The tribological properties of n-PbS as lubricating additive were evaluated with block-on-ring tfibotester. The results show that the delamination of n-PbS dispersion system don＇ t come into being through 72 h centrifuge test and 56 h intermittent high speed centrifuge test, the diameter and size distribution of n-PbS are 21.6 nm and 2.8 nm respectively,n-PbS as lubricating additive can effectively enhance the friction-reduction and antiwear ability of liquid paraffin,and the extreme pressure property can increase 100 percent at the content of 0.05 -0. 3 percent n-PbS.