润滑剂的功能

The function of lubricants

就聚合物加工而言﹐磨擦主要包括聚合物树脂或胶料与加工机械表面和聚合物内部分子之间相互磨擦两方面的内容﹐即外部磨擦和内部磨擦。与之相对应﹐外部润滑作用用来减少外磨擦﹐内部润滑作用旨在降低内磨擦。具有外部磨擦作用的润滑剂称为外润滑剂﹐具有内部润滑作用的润滑剂称为内润滑剂。通过内外两种润滑作用﹐聚合物加工过程不仅可以防止树脂熔体或胶料粘附在加工机械表面﹐提高流体速率﹐降低剪切扭矩﹐节能降耗和增加产能﹐而且由于磨擦生热的降低能够有效的抑制树脂或胶料的降解﹐提高稳定剂的效率。对于一个完整的聚合物加工过程来说﹐内部润滑作用和外部润滑作用是不可分割的﹐理想的润滑剂应当同时兼备良好的内润滑性和外润滑性。通常内部滑与外部滑只是相对而言，无明确界限，内部滑剂略为增量便有外部滑性效果，外部滑剂相对材料也有内部滑性存在；选择时不必斤斤计较如何划分滑剂类别，应视加工设备、加工温度，以及材料配合剂的不同，适材适量才是要点。内滑用量过多时会渗析出来而推迟塑化时间；外滑剂过量时会导致物料对机筒打滑，容易出现不稳定流动，影响制品质量。

As far as polymer processing is concerned, friction is mainly composed of two aspects of the friction between polymer resin or the surface of the machined surface and the internal molecules of the polymer, that is, external friction and internal friction. Correspondingly, external lubrication is used to reduce external friction, and internal lubrication is designed to reduce internal friction. Lubricants with external friction are called external lubricants. Lubricants with internal lubrication are called internal lubricants. Through two kinds of internal and external lubrication, the process of polymer processing can not only prevent the adhesion of resin melt or adhesive on the machined surface, improve the fluid rate, reduce shear torque, save energy and reduce consumption and increase productivity, but also can effectively inhibit the degradation of resin or glue and improve the effect of stabilizer because of the reduction of friction heat. Rate. For a complete process of polymer processing, internal lubrication and external lubrication are inseparable. Ideal lubricants should also have both good internal and external lubrication. Generally, the internal slippery and external slippage are only relative, there is no definite boundary, the internal sliding agent is slightly incremental and has external slippery effect, and the external sliding agent has internal slippery property; it is not necessary to consider how to divide the category of the slide agent, depending on the processing equipment, the processing temperature, and the material mixture. Right amount is the point. When the amount of internal sliding is too much, the plasticizing time will be deferred; when the overdose is overdosed, it will cause the material to skid to the barrel, easy to appear unstable flow and influence the quality of the product.