UV protection applications

One of the uses of carbon black in the plastics industry is anti-UV aging. Due to its high absorbance, carbon black can effectively prevent the plastic from photooxidative degradation caused by sunlight. The role of carbon black as a UV stabilizer in plastics includes converting light energy into heat energy, protecting the plastic surface from radiation of a certain wavelength, intercepting radicals and generating anti-aging effects, thereby preventing catalytic degradation. Ultraviolet light is particularly harmful to polyolefins. Experiments have shown that a perfect UV shielding effect can be achieved when the carbon black concentration of a certain degree of fineness is 2%.

The protective effect of carbon black on the UV aging of plastics depends on the particle size, structure and surface chemistry of the carbon black.

When the particle size of carbon black is small, the protective effect of UV rays is enhanced because the surface area increases and the light absorption or light-shielding ability increases. However, when the particle size is less than 20 nm, the protective effect tends to be the same level because when the particle size is too small, Scattering decreases, while continued forward light can threaten the stability of the polymer.

Lower structures, ie, smaller aggregate sizes, increase the protective effect on the polymer due to the smaller aggregate volume, which is why black carbon with a lower structure is darker. The oxygen-containing groups on the surface of carbon black are more, that is, when the volatile matter is higher, the gene generated when the polymer is decomposed can be eliminated, and the protective effect is also enhanced.

One injection masterbatch is divided into senior and ordinary senior masterbatch is mainly used for cosmetic packaging, automotive ABS, advanced PVC synthetic leather, household appliances and other senior shell products. The requirements of the pigment masterbatch with pigment dispersion, in particular, requires coloring products colorless spots, stains. Carbon black should use small particle size, low structure of the pigment black, because the main black base for the absorption of light, the smaller the particle size, the higher the light absorption, the weaker the light reflection, the higher the black, the product generally dark hair bright.

Ordinary grade masterbatch is mainly used for PE trash bags, cables, pipes and other products, high-grade film requires pigment particles small, evenly dispersed, the film should not have a color point greater than 0.6mm, the common film can choose larger particle size , High structure, medium blackness, good dispersion ordinary pigment black can.

Fiber Masterbatch is divided into polypropylene, polyester. Mainly used for chemical fiber silk, carpet, non-woven fabrics. Requires carbon black contains high purity, good dispersion, high tinting strength, no impurities, pigment particles less than 1um.