Titanium dioxide is an important whitening agent in industrial production, and it is widely used in coatings, paints and other industries. It has good tinting strength and strong hiding power and is the preferred whitening agent for white paints. Titanium dioxide can be divided into two types: anatase titanium dioxide and rutile titanium dioxide, which also have different applications in the industry. Titanium dioxide can not only show its talents in the coatings industry, but also has a great role in the plastics industry. The following describes the elastic application of rutile titanium dioxide in plastic sheets.
Sheets are flexible and come in many varieties, and are widely used in the plastics industry:
(1) Muscovite
White, light yellow, brown or ribbed red, transparent sheet, specific gravity 2.76-3.1, hardness 2.0-2.5
(2) biotite
Black, dark brown or dark green, specific gravity 2.8-3.2, hardness 2.5-3.0.
(3) Phlogopite
Phlogopite is also called magnesium mica, yellow to dark brown. Mica has excellent heat resistance, acid and alkali resistance and electrical linearity. Mica powder is also easily mixed with the resin.
(4) Talc
White or light yellow, monoclinic, often in the form of flakes, scales or dense block aggregates. Glass luster, flaky cleavage is extremely complete. The talc has a slippery feel, is extremely soft, is chemically inert, and has good fire resistance and electrical insulation.
(5) Calcium silicate (wollastonite)
Calcium silicate can also be called wollastonite, which is used to improve the chemical and moisture resistance of thermosetting resins, PVC, polyolefins, nylons and epoxy resins. Anatase titanium dioxide reduces mold shrinkage and has excellent dimensional stability. Insulation, toughness, hardness, electrical and thermal insulation.
(6) Hollow microspheres: Hollow microspheres can be produced by various methods such as melt jet method, direct heating foaming method, foaming agent foaming method, core material decomposition method, heating carbonization method, chimney ash recovery method, and the like.
Silica
(1) Diatomaceous earth: Diatomaceous earth is a biochemical sedimentary rock composed of siliceous cell walls of diatoms. Light yellow or light gray. It is soft, porous and light, easy to grind into powder, strong in water absorption, soluble in strong alkali solution, and is a material of heat insulation, sound and electricity.
(2) Quartz: Quartz is a widely distributed rock-forming, trigonal system. It is often a hexagonal column and a hexagonal double-tapered crystal, and is formed into crystal clusters and crystal cavities. Transparent, translucent or opaque. No cleavage, shell fracture. The crystal face has a glass luster. Anatase titanium dioxide fracture is a glass luster similar to fat luster. Quartz powder is generally used as a filler in the plastics industry.
(3) Silica: Silica is widely distributed in nature, white or colorless.
Silica has good heat resistance and chemical resistance, and has low thermal expansion coefficient and good electrical insulation performance.
(4) Silica (also known as colloidal silica, hydrated silica, fumed silica).
White amorphous fine powder with a refractive index of 1.46. The particle size and water content vary with the method of preparation. White hair black is good in insulation, insoluble in water and acid, soluble in caustic and hydrofluoric acid, not decomposed by high temperature, strong in water absorption, easy to deliquesce in public air, similar in performance to carbon black, but white, in the air After absorbing moisture, it becomes aggregated fine particles.
Metal oxide
Titanium dioxide (also known as anatase titanium dioxide)
Rutile and ilmenite are the two most important natural minerals for the production of titanium dioxide. In the plastics industry, rutile is mainly used, which is reacted with chlorine gas to form titanium tetrachloride, and then hydrolyzed to obtain pure titanium dioxide.
Titanium dioxide used in plastics should be a white powder with good light resistance, although in plastics, especially in polyvinyl chloride formulations, the application of titanium dioxide can reach 50 parts in 100 parts of resin, but strictly speaking, it is generally not The filler is used as a versatile white pigment.
In addition, such as zinc oxide and antimony trioxide are also white powdery materials, and like titanium dioxide, it is also a white pigment having a filler action.
Metal powder
In order to make the plastic have the color of the metal, increase the electrical conductivity, thermal conductivity and increase the rigidity, hardness, heat resistance, etc., various amounts of various metal powders are often added to the plastic.
Atactic polypropylene (referred to as APP)
When propylene is polymerized by Ziegler-Natta catalyst, about 95% of high isotacticity can be obtained, but after all, 5% of random polypropylene exists, they are viscous materials, and have no mechanical strength and heat resistance. Therefore, it has been a burden of polypropylene production plants. However, in recent years, it has been found that the APP-filled masterbatch made of a certain amount of calcium carbonate mixed in the random polypropylene can play a good role in the processing of polypropylene, polyethylene and polyvinyl chloride, and the addition amount is generally up to About 20%. This not only makes the random polypropylene a way to turn waste into treasure, but also improves the plasticity, toughness and elasticity of the filled plastic, and reduces the production cost of the polypropylene. Polypropylene filled with APP as a filler can be used to produce packaging tapes, tear films, flat yarns, woven bags, totes, hollow containers, and the like.
