SUNNYJOINT comments on Application Performance Analysis of Titanium Dioxide

- Dec 12, 2018-

Shenyang SUNNYJOINT as a supplier of Rubber Additives, In recent years, The plastics industry is the second largest user of titanium dioxide, the fastest growing field in recent years, with an average annual growth rate of 6%. Of the more than 500 titanium dioxide grades in the world, more than 50 grades are plastic-specific. In addition to its high hiding power, high achromatic power and other pigment properties, the application of titanium dioxide in plastic products can also improve the heat resistance, light resistance and weather resistance of plastic products, and protect plastic products from UV light. Invasion, improving the mechanical and electrical properties of plastic products.


Since plastic products are much thicker than paints and inks, they do not require too much pigment volume concentration, and they have high hiding power and strong tinting strength, and the general dosage is only 3% to 5%. It is used in almost all thermosetting and thermoplastic plastics, such as polyolefins, polystyrene, ABS, polyvinyl chloride, etc. It can be mixed with resin dry powder or with plasticizer-containing liquid. Some are used after processing titanium dioxide into masterbatch.


Most plastics use titanium dioxide with a fine particle size. Usually, the particle size of titanium dioxide for coatings is 0.2~0.4ΜM, and the particle size of titanium dioxide for plastics is 0.15~0.3ΜM, so that the blue bottom phase can be obtained. Most yellow-colored resins or yellow-yellow resins have a shielding effect.


Titanium dioxide for ordinary plastics generally does not undergo surface treatment, because the inorganic coated titanium dioxide such as conventional hydrated alumina, when the relative humidity is 60%, its adsorption equilibrium water is about 1%, when the plastic is extruded at high temperature. When processing, water evaporation will lead to the appearance of pores on the smooth plastic surface. This non-inorganic coated titanium dioxide is generally subjected to organic surface treatment because titanium dioxide for plastics is different from titanium dioxide for coatings. The former is In the low-polarity resin, the organic surface-treated titanium dioxide can be better dispersed by shearing force processing and mixing under appropriate mechanical shearing force.


With the continuous application of plastic products, many external plastic products, such as plastic doors and windows, building materials and other outdoor plastic products, have high requirements on weather resistance. In addition to the use of rutile titanium dioxide, surface treatment is required. This surface treatment is generally free of zinc, and only silicon, aluminum, zirconium, etc. are added. Silicon has a hydrophilic dehumidification effect, which prevents pores from being generated by evaporation of water when the plastic is extruded at a high temperature, but the amount of these surface treatment agents is generally not too much.


The composition of the plastic includes resin, filler, plasticizer and other auxiliaries. According to the processing method of the product, it can be divided into extrusion blow molding process of plastic film, extrusion molding process of plastic sheet and plastic injection molding process, for example:


Extrusion blow molding process for plastic film:


Resin, filler, auxiliaries, masterbatch, batching, blown film, plastic film


The main equipment used in this process is a two-roll mill, a blown film machine, and the like.


The plastic injection molding process includes plasticizing, injection and molding cooling. The common equipments include embolic injection machines and screw injection machines.


The quality requirements for titanium dioxide in plastic products are:


1) Covering power: Titanium white with good hiding power, and the produced plastic products are lighter and thinner;


2) Whiteness: Determine the appearance of light or white plastic products;


3) Dispersibility: affecting the production cost of plastic products. Titanium dioxide with poor dispersion will affect the smoothness and brightness of the products in plastic products;


4) Weather resistance: Plastic products for outdoor use, plastic doors and windows, etc. must ensure the weather resistance of titanium dioxide.


Masterbatch


The plastic masterbatch is a highly concentrated, high-performance color formulation in which the pigment is uniformly distributed in the carrier resin at an extraordinary concentration and forms particles of a certain particle size. It is mainly composed of core layer, coupling layer, dispersion layer, mixed layer, etc. It is used as a dyeing agent in plastics, and is widely used in the production of plastic products such as blown film, injection molding, hot pressing, injection molding, etc. Superior, easy to use, energy saving, no dust and sewage when used, it is highly favored by users.


The development of color masterbatch is very fast, and the production process of masterbatch is simple, and the