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Dry treatment method for the surface of fillers. Dry surface polymerization treatment of fillers is a relatively novel surface treatment method. There are generally two approaches: one is to first treat the surface of the inorganic filler with an appropriate initiator such as a peroxide, then add the monomer, stir at high speed, and allow the monomer to polymerize on the surface of the filler at a certain temperature, thereby obtaining dry fillers that have undergone surface polymerization ； Another method involves grinding the monomer and filler in a ball mill; the mechanical force of grinding and the frictional heat generated enable the monomer to polymerize on the surface of the inorganic filler, thereby yielding filler with a surface-polymerized treatment. ①Principle and process of dry treatment: The principle of dry treatment is that, in a dry state at a certain temperature, high-speed mixing is used to ensure that the treatment agent is evenly applied to the surface of the filler particles, thereby forming an extremely thin surface treatment layer. Dry processing can be used for surface treatment via physical methods as well as chemical methods, especially in dry processing processes that involve crushing or grinding. Whether it is physical or chemical action, excellent surface treatment results can be achieved. Clearly, this surface treatment effect is closely related to the continuously emerging highly active surfaces of the fillers during the treatment process as well as the reduction in the particle size of these fillers, and it has become a very notable new trend in development. ②Surface polymerization treatment: Many fillers have reactive groups on their surface, which can react with certain polymerizable monomers; these monomers are then polymerized, thereby forming a layer of polymer over the surface of the filler through chemical bonds. When such polymers are mixed with plastic resins, they exhibit good miscibility, which enables an improvement in the interfacial adhesion between the filler and the matrix resin, **thereby enhancing the mechanical properties of the filled modified plastics. ③Surface coating treatment: The treatment agents can be liquids, solvents, emulsions, or low-melting-point solids. The general procedure involves mixing them evenly and then gradually raising the temperature to a certain level; at this temperature, high-speed stirring is carried out for 3–5 minutes before the product can be obtained. ④Surface reaction treatment: There are two types of dry surface reaction treatment methods. One involves the use of treatment agents that can form strong reactions with the surface of the fillers, such as aluminates and titanates, which react directly with the filler surface ； Secondly, two types of treatment agents are used in sequence for reaction treatment; that is, the first treatment agent reacts with the surface of the filler and binds to it through chemical bonds, after which the second treatment agent reacts with the first treatment agent that is bound to the filler’s surface.