Barium sulfate, also known as barite, is a colorless, odorless, non-toxic inorganic compound with a chemical formula of BaSO4. It has high density, high whiteness, good chemical stability and acid and alkali resistance, and is insoluble in water and most acids. These characteristics of barium sulfate make it widely used in many fields.

1. Natural barium sulfate-barite powder

Baryte is a white or gray powder with coarse particles, generally 2-5μm in size, brittle, pH 4.5, obtained by crushing and grading, with a fineness of 250 mesh, and a barium sulfate content of more than 90%.

2. Artificially synthesized barium sulfate-precipitated barium sulfate

Precipitated barium sulfate is purer in quality and smaller in particle size. The particle size distribution is 4% of 1.5-2μm, 10% of 1.0-1.5μm, 46% of 0.5-1.0μm, 10% of 0.5μm, and 40% below 0.5μm. The pH value of synthetic barium sulfate is 6.6-8.0.

Barium sulfate is widely used in plastics, mainly in the following aspects:

01. Filling modification

As a functional filler, barium sulfate can improve the hardness, strength and heat resistance of plastics. It is often used to modify general plastics (such as PP, PVC) and engineering plastics (such as PA, PET) to improve their physical properties and processing properties. For example, the addition of barium sulfate can significantly improve the gloss and hardness of PP, making its surface similar to ABS without affecting other properties of PP.

02. Chemical corrosion resistance

Barium sulfate has good chemical inertness and can enhance the chemical corrosion resistance of plastic products. It is suitable for applications that require durability such as home appliance housings and automotive parts.

03. Improve appearance

The high whiteness and gloss of barium sulfate enable it to improve the appearance of products and increase visual appeal when used in plastics. For example, adding barium sulfate functional masterbatch to BOPP film can improve the gloss and whiteness of the film and enhance the printing effect.

04. Reduce costs

Due to the relatively low cost of barium sulfate, its use as a filler can effectively reduce the production cost of plastic products. Generally, filling with barium sulfate can reduce the need for other expensive fillers (such as titanium dioxide), thereby reducing the overall material cost.

05. Enhanced mechanical properties

The addition of barium sulfate can improve the tensile strength and impact strength of plastics, especially in composite materials. For example, studies have shown that the tensile strength and flexural strength of PA66 composites with activated barium sulfate are significantly improved.

Based on these characteristics of barium sulfate, we will introduce two common functional masterbatches for films today: pearlescent masterbatches and light diffusion masterbatches.

01. Pearlescent masterbatch

Principle-reflection: Pearlescent film production is generally made of polypropylene resin as raw materials, calcium carbonate and pearlescent pigments are added, and then biaxially stretched. In the actual production process of pearlescent paper, micro-particle calcium carbonate masterbatch is evenly dispersed in PP. After biaxial stretching, uniform holes are formed. When light is irradiated, part of the light is reflected, and the other part is continuously reflected in the holes, thereby producing a pearlescent effect.

Pearlescent agent: barium sulfate, calcium carbonate, silicon dioxide

Application:BOPET pearlescent film is widely used in advertising, printing, labeling, food packaging and other industries.

Product: MTA10289-A1 pearlescent masterbatch of Suzhou PPM Material Technology Co., Ltd. is a cost-effective product specially customized for the BOPET industry. The produced BOPET pearlescent film has a smooth surface without crystal points, high hiding power, pure white color and good pearlescent effect.

02. Light diffusion masterbatch

Principle-refraction: Adding inorganic or organic light diffusers to the transparent matrix, the light will be refracted countless times through the surface of tiny particles to achieve the effect of light diffusion, that is, uniform light.

Inorganic light diffusers: barium sulfate, silicon dioxide

Organic light diffusers: styrene type, acrylic resin type, etc.

application:

Product: Poly Plastic Masterbatch (Suzhou) Co., Ltd's MTA10381-A1 light diffusion masterbatch uses a highly efficient and stable light diffuser for BOPET diffusion film, which can effectively reduce light energy loss and improve light transmittance; at the same time, after multiple refractions, reflections, and scattering of light, it achieves a soft light effect and high haze. Main application: LCD display backlight source film

Masterbatch product picture:

Pearlescent Masterbatch

光扩散母粒