What are the advantages of using excellent filler barium sulfate in nylon modification?

Barium Sulfate, also known as barite, is a colorless, odorless, non-toxic inorganic compound with the chemical formula BaSO4. It is known for its high density, high whiteness, good chemical stability and acid and alkali resistance, and is insoluble in water and most acids. These characteristics make barium sulfate widely used in many industrial fields, especially in the field of plastic modification, especially in the modification of nylon (PA), where barium sulfate shows unique advantages.

Nylon, as a polymer material with excellent mechanical properties, wear resistance, acid and alkali resistance and self-lubrication, is widely used in many industrial fields. However, the disadvantages of nylon such as high water absorption and poor dimensional stability limit its application range. Therefore, it is particularly important to modify nylon to improve its performance. As a neutral filler, barium sulfate plays multiple roles in nylon modification, such as strengthening, toughening and improving gloss.

Reinforcement effect

As an inorganic filler, the addition of barium sulfate can significantly improve the rigidity (modulus) and hardness of nylon, and is suitable for industrial parts that require high modulus (such as gears and bearings). Relevant experimental results show that with the increase of nano-barium sulfate content, the bending modulus and tensile modulus of nylon are improved. In particular, when the mass fraction of nano-barium sulfate is a certain value (such as 3%), the mechanical properties of nylon reach the best. This reinforcement effect is mainly due to the rigidity of barium sulfate and its good interface bonding with the nylon matrix.

Dimensional stability: reduce the shrinkage and warping of nylon during processing or use, and improve dimensional accuracy.

Heat deformation temperature (HDT): by limiting the movement of polymer chains, improve the thermal stability of materials, and expand the application of nylon in high temperature environments (such as automobile engine parts).

Toughening effect

In addition to the reinforcement effect, barium sulfate can also have a toughening effect on nylon. The interaction between nano-barium sulfate particles and the nylon matrix forms an elastic transition layer, which can effectively transmit and relax the stress on the interface, thereby absorbing and dispersing the external impact energy and improving the toughness of the material. However, it is worth noting that when the content of barium sulfate increases to a certain extent, the performance of the material will be reduced due to the occurrence of agglomeration.

Improved gloss

Barium sulfate has a strong light reflection ability in the ultraviolet and infrared wavelength ranges, which enables it to show high brightness in plastic coloring formulas. When barium sulfate of appropriate particle size is selected to be filled in nylon, the surface gloss of the processed products can be significantly improved. In addition, the refractive index of barium sulfate is similar to that of polymers such as nylon, so it can retain the brightness and hue of the coloring pigment.

Practical application

In practical applications, barium sulfate is usually uniformly dispersed into the nylon matrix in the form of nanometers by melt blending. This method utilizes the size effect, large specific surface area and strong interfacial force of nano-barium sulfate, and perfectly combines the rigidity, dimensional stability and thermal stability of barium sulfate with the toughness, processability and dielectric properties of nylon, thereby obtaining excellent comprehensive performance.

Barium sulfate has shown significant enhancement, toughening and gloss improvement in nylon modification. By rationally controlling the content and particle size distribution of barium sulfate, it is possible to optimize the mechanical properties of nylon, improve the durability and aesthetics of the product, balance performance and cost, optimize the formula design for specific scenarios, and thus broaden the application range of nylon.