The addition of fillers solve materials science, technology and technical and economic problems.
increase the strength properties, including reinforcement;
regulation of thermal deformation characteristics;
imparting specific properties of the polymeric material (density or porosity, conductivity, magnetism, thermal conductivity or specific heat, friction and antifriction or others);
regulation of technological properties (melt viscosity and its stability, the pace of the transition from viscous to solid state, especially molded products and their removal from the equipment);
imparting decorative properties;
reducing the cost of using cheap varieties of toppings.
Requirements to excipients:
good wettability of the liquid polymer;
ability to be combined with the polymer to form a homogeneous mixture (for disperse fillers);
invariability properties during storage and during processing;
minimum cost.

The most important characteristic of fillers is their morphology and specific surface area, which determines the efficiency of interaction with the polymer matrix, particularly when they fillers are treated with surfactants, modifiers and other additives.

As main features, defining a method for processing polymeric material in a product can be classified as fillers

The group dispersed fillers is the most diverse in properties. As the powdery filler dispersed more or less effectively used in virtually any measurable pulverized products as inorganic and organic origin. There are author’s certificates on the composition with the skin walnut cache th, husk legumes, fruit pits, tripoli, Teflon powder and others.

Among the organic fillers dispersed most widespread wood flour, which is finely powdered and dried wood fiber structure. The dimensions of its particles are less than 100 microns, bulk density – 150 kg / m3. Used for the production of press powders and alkyd linoleum. Dignity – the low cost, good impregnability solutions; drawback – low chemical and thermal resistance, hydrophilic.

In recent years, as a dispersed filler distribution obtained powdered synthetic polymers such as PTFE fine 4NTD-F, which is used as a filler in the antifriction thermosetting matrices.

Of the inorganic thin and medium size fillers most widely used carbon black, chalk, kaolin and natural silica.

Carbon black is used as an effective filler structuring LDPE, PVC, HDPE, PP, PFP, ES. Introduction soot contributes to the durability of products, increases their resistance svetostareniyu.

Mel in the form of thin and medium size fractions is widely used for filling polyolefins and polyvinyl chlorides. In an amount up to 20% is administered, for example, polypropylene plastic used for the production of furniture. Chalk drawback – availability and hydrophilicity of the water of crystallization.

Kaolin with particle size of 1 micron is used as the translucent polymer structuring additive and a fine fraction – filling LDPE, HDPE, LLDPE, PVC.

Asbestos – continue to be used for filling heat and, much broader thermosets. It increases the strength of plastics, increases their resistance to aging and burning. As the flame retardants used as sulfates of barium and calcium.

Metal powders and alloys improve electrical and thermal conductivity of plastics, improve their tribological characteristics.

Introduction fillers dispersed in relatively small amounts (up to 10%), usually helps to preserve or even improve some strength (Fig. 5) of polymeric material. If C> 10% of the physical and mechanical properties of the composite additive is reduced.

Morphologically granular fillers are hollow spheres, flakes, leaves up to a few millimeters. In some cases, they have a reinforcing effect. Most particulate fillers are used to impart special properties of plastics, for example, reflective, to increase the coefficient of friction, to reduce the density (Steklosfery).

The fibrous fillers on the range much smaller than dispersed. Most common among these are glass fibers, carbon fibers, cotton and synthetic fibers, as well as their production of waste, and a monofilament single crystals whiskers of metal oxides, and metalloids.

The fibers can be chopped (short and long fiber) and continuous in the form of a felt or roving. Therefore fibrous fillers can exhibit properties as close to the particulate and reinforcing (reinforcement). Use of chopped fiber, particularly of short, allows for processing such materials into articles by extrusion or high-pressure casting.

Concentration optimum properties chopped fibrous filler accounts for 40-50%.

The use of continuous fibers has a reinforcing effect on the polymeric material.

Depending on the physicochemical properties of the particular fiber strength properties of the composite can be higher than in the polymer matrix in the tens or even hundreds of times. Thus, the use of the “whiskers” allows you to bring the composite modulus of elasticity in the epoxy binder to 100-300 GPa, though the epoxy resin of the unit is 3-6 GPa.

Traditional fiberfill are glass fiber (ST). They are relatively inexpensive and readily available. Produced from a large range of glass fibers, which differ in their chemical composition, diameter and strength. The disadvantages include glass brittleness finishing agents and the presence of coatings that reduce the adhesion to the polymer.

Glass fibers are used to reinforce thermoplastics (PA, PP, PD, PC, HDPE, PVC), and especially thermosetting plastics, epoxy resins, unsaturated polyesters and fenolofor maldegidnyh-oligomers.

The thermoplastics administered to 40% and a thermosetting binder – 80% glass fiber.

Carbon fiber (CF) was prepared by treating a high-temperature inert gas synthetic fibers of polyacrylonitrile, pitch or other polymers. Therefore, HC elastic NE, has a developed surface and the effect occurred graphitization (carbonization) acquires besides the strength also features enhanced thermal and electrical conductivity, wear resistance and anti-friction. Naturally, such a set of characteristics significantly expands the range of technological and operational properties of carbon fiber reinforced plastics, which are currently the most promising materials for the aerospace industry, high-speed transport engineering and shipbuilding, for pipelines and storage tanks petrochemical complex products.

Tissue fillers are made primarily on the basis of cotton, glass and carbon fabrics. They are used to obtain high-strength reinforced anisotropic materials. Depending on the morphology of the roller used fabrics, woven tapes and cords, and unidirectional tape, in which high-strength fibers carrying “bases” are connected into a continuous ribbon yarns rare “duck”. To date, such fillers reinforced plastics have the highest set of physical, mechanical, thermal deformation, thermal and operational properties. As a binder, it is generally used epoxy oligomers, polyimides, unsaturated polyesters. The filler content in the composite may vary in the range of 40-85%.

Nonwoven fillers used in the form of paper, cardboard, felted mats, nets. They all serve to impregnation usually solutions of polymeric binder, followed by drying from the solvent and processing products mainly in compression. Use of the decorative paper as the outer layer produces decorative plastics are widely used, for example, in furniture production. Nets and mats are also used for the production of materials with special properties (low density, controlled porosity, hybrid design).
Thus, the use of fillers different in properties, morphology and content within the composite allows to adjust within broad limits many physical, technological and operational properties of plastics.