Application of Calcium Carbonate as a Volumizing and Weight Increasing Filler in Greases
In the production of grease, often applied to the filler, they are non-oil-soluble solid additives, mostly a number of lubricating effect and enhance the sealing and protective effect of non-oil-soluble solid powder. Among them, most of the grease fillers themselves have the role of solid lubricants, adding grease can improve the lubricating properties of the grease.
Commonly used fillers in grease are graphite, molybdenum disulfide, zinc oxide, titanium dioxide, lead monoxide, boron nitride, etc. Their addition can play a reinforcing role in the grease to improve water resistance and loss, enhance sealing and protective properties, etc.
Calcium carbonate powder is widely used in industry because of its green, non-toxic and low price. With the development of particle size refinement, controllable crystal shape and surface modification of calcium carbonate, calcium carbonate as a filler can realize the development of functional reinforcing materials from ordinary capacity-enhancing and weight-enhancing materials, so as to make the quality of the products improved.
As a grease additive as the basis of research, calcium carbonate to become a grease capacity increasing weight filler, there are the following points to consider:
1, surface modification. Calcium carbonate is a polar inorganic material with hydrophilic and oleophobic surface, poor affinity with oil and agglomeration. Base oil is the grease in the quality of the largest proportion of components, in order to enhance the affinity with oil, calcium carbonate in the grease as a filler before the surface modification should be required.
2, particle size ultrafine. Nanomaterials have unique and excellent performance, nowadays there are a lot of scholars on its application in grease research. Nanoparticles can be used as lubricating grease additives, mainly the following three advantages: First, the diffusion and self-diffusion ability of nanoparticles is strong, can be better in the metal friction surface to form a good penetration layer or diffusion layer, to achieve the effect of anti-friction; Secondly, the particles with a small particle size in the shape of a spherical shape, in the friction surface to play a similar role as the "rolling bearing", to change the friction surface, to change the friction surface. Secondly, the particles with small particle size are almost spherical in shape, playing a similar role as "rolling bearing" on the friction surface, changing the lubrication mode of the friction vice, and achieving the effect of reducing the coefficient of friction.
3、Crystal shape of calcium carbonate. For calcium carbonate, crystal shape is a very important technical index, which determines the usage. When calcium carbonate is used as the filler of grease, it is also necessary to choose the appropriate crystal shape. At present, calcium carbonate in the lubrication field of application, the shape of the main cubic, spherical and indeterminate shape.
Calcium carbonate as a filler for grease has the advantages of being green and inexpensive. On the premise of not affecting the performance of the grease, calcium carbonate to the grease to increase the capacity and weight, can reduce the use of grease raw materials, is conducive to the protection of the environment as well as to reduce the cost of production.
