This type of additive has many overlapping properties; Certain materials, such as glass, may be used as a reinforcer in one case and as a filler in another. Amplifiers are commonly known as additives that increase mechanical properties (such as tensile strength). Fillers are additives that add volume to the polymer and are commonly used to reduce the cost of materials. Some of these additives are mentioned below. Calcium carbonate is a mineral that is mainly obtained from limestone. This material is widely used as a filler. In some cases, it is used to increase the impact resistance of polymers and also to improve the appearance of the surface. One of the advantages of using this material, which has led to an increase in its consumption today, is its low heat capacity compared to polyethylenes. This improves the cooling intensity and thus increases the output. However, excessive use of this material increases corrosion in the material transfer system, extruder and.. Carbon is used as an additive in two main ways: soot and carbon fiber. Both are moisture absorbers and are usually dried before extrusion or used in porous extruders. Soot is a powdery substance and due to its ability to absorb ultraviolet waves, it is mostly used in the production of packaging films for light-sensitive materials that are stored outdoors. This increases the service life of polymer processing equipment. In addition, it is a strong pigment and also has a relatively low price and the ability to increase electrical conductivity. One of the major obstacles to soot consumption is that it is difficult to work with and the resulting dust can cause contamination. To solve this problem, the granular type, which is more expensive, is used. Fiber carbon is a reinforcing material and despite being expensive, it is very durable and greatly enhances the mechanical properties of polymers. When these materials are used in extrusion, they rapidly form small fibers in the polymer matrices. In addition to the amplifying properties, the electrical conductivity of fibrous carbon has led to their use in cases where electrostatic charges need to be dispersed. Clay is very popular today. Clay enters the process in powder form. If the powders are microscopic (nanometers) in size, they are shaped into plate lumps. Clay is also known as nanocomposite material due to the penetration of polymer matrices between the clay plates. By considering the appropriate process conditions, the clay plates can be separated from each other to improve the properties. The mechanical properties and impermeability to gases are greatly improved by clay. Glass is used in two major forms in the polymer industry. Glass spheres and glass fibers. Glass balls can be used as fillers to reduce costs. But it also has other good properties. Empty glass spheres decrease overall density with constant weight and often increase tensile properties. Solid glass spheres often enhance mechanical properties. They are also used in highways, such as road signs and information, due to their reflective properties. Glass fibers are very strong and act as reinforcers, at an acceptable price, very well. These materials have different types according to the needs such as strength, electrical or chemical properties and are used as small fibers in extruders. If you consume a large percentage of these materials, severe corrosion will occur on Screw and Mardon. Talc (magnesium silicate) is used as a filler but also improves its mechanical properties. The sheet structure of this material increases the toughness and processing temperature. Talc is softer than many other mineral fillers. Therefore, it does not cause much corrosion of the equipment. Wood powder, now used as a filler for thermoplastics, is inexpensive and gives some of the properties of natural wood to plastics, such as the appearance, texture and aroma of wood. Due to the presence of polymer matrices, products that contain this additive have a longer lifespan than similar wood products and are more resistant to the destructive effects of moisture. Compatibilizers are also used to increase the adhesion between polymer matrices and these additives to have good mechanical properties.
