The plastic industry is the second largest application area of titanium dioxide. For that, different application fields have different requirements on the performance of Tio2 pigment. There is special titanium dioxide for plastic. It has properties of high hiding power, high color reducing power, excellent whiteness. So titanium dioxide pigment can also improve the heat resistance, light resistance and weather resistance of plastic products, protect plastic products from UV light. Meanwhile, it can also improve the mechanical and electrical properties of plastic products.
Since the coating film of plastic products is much thicker than paint and ink, it doesn’t need too high pigment volume concentration. In addition, it has high hiding power and strong tinting power, the general dosage in plastic is only 3%-5%. It is suitable for almost all thermosetting and thermoplastic plastics, such as, polyolefins, polystyrene, ABS, polyvinyl chloride, etc. Mixing it with dry resin powder, or liquid containing plasticizers for use is possible. Processing it into masterbatch is also one of the methods of use
There are four main indicators to measure the quality of titanium dioxide for plastic, hiding power, dispersibility, weather resistance and whiteness. The better the hiding power, the lighter and thinner the plastic products produced. The dispersion affects the production cost of plastic products. The better the dispersion, the higher the smoothness and brightness of plastic products. Titanium dioxide with good weather resistance is essential for out door plastic products, such as plastic doors and windows.
Generally, the particle size of titanium dioxide for paint and coating is 0.2~0.4μm. While most of the titanium dioxide for plastic has a finer particle size of 0.15~0.3μm. For that, it can obtain a blue base phase, which has a masking effects on most resins with yellow phase or resins prone to yellowing.
Ordinary Tio2 for plastic generally doesn’t undergo surface treatment. Titanium dioxide coated with conventional hydrated alumina and other inorganic materials. When the relative humidity is 60%, its absorption equilibrium water is about 1%. When the plastic is extruded at high temperature, the evaporation of water will cause pores on the smooth plastic surface. This kind of titanium dioxide powder coated without inorganic substances generally has to undergo organic surface treatment. Titanium dioxide for plastic is processed and mixed by shearing force in low-polarity resin. After organic surface treatment, it can be better dispersed under appropriate mechanical shearing force.
Plastic masterbatch is a highly concentrated, high efficiency color configuration product, that is, the pigment is uniforly distributed in the carrier resin at an extraordinary concentration and forms particles of a certain size. It is mainly composed of core layer, coupling layer, dispersion layer, mixing layer, etc… The masterbatch is use as a coloring agent in plastics, and is used in the production of blown film, injection molding, hot pressing, injection molding and other plastic products. With the characteristics of superior coloring effect, convenient use, energy saving, no dust and sewage when used, masterbatch is favoured by users.
Masterbatch can be used to match colors of PVC, polyethylene, polystyrene and ABS plastics. Its main ingredients are pigments, resins, dispersants, volume pigments, fluorescent whitening agents, antioxidants, anti-ultraviolet agents, antistatic agents, toughening agents, brighteners, etc… Titanium dioxide is used as a white pigment, which has the advantages of no poisonous, stable chemical properties, high hiding power, good dispersion, etc…
Masterbatch is used as an industrial raw material, its performance is usually manifested in subsequent products applications. Therefore, the performance of titanium dioxide for plastic in the color mesh is mainly reflected in the application process of the color masterbatch. The coloring ability, dispersibility, processing performance and whiteness will have a significant impact on the application of masterbatch.
The refractive index, durability and color gloss of titanium dioxide for plastic make it an ideal additive for plastics used outdoors. It can provide plastics with vital hardness that is resistant to weathering and light damage.