Application of high performance silicon material in plastic modification

2024-11-15 14:00:16 Jiangxi dstone 103

Among many types of inorganic powder materials, high-performance silicon material is a special one, which is especially reflected in its diversity and complexity. High-performance silicon material has the characteristics of stability, fiber structure, oleophilic and hydrophobic, and few in nature can combine so many advantages as high-performance silicon material. High-performance silicon material is a rare functional material because of its own characteristics. In many applications, high-performance silicon materials can reduce the cost of products and significantly enhance many properties of these products. Widely used in papermaking, plastics, paints, coatings, ceramics, cosmetics, medicine, rubber, agricultural products, fertilizers and other industries.

In the process of plastic modification, the addition of high-performance silicon materials can improve many properties of plastics, such as molding shrinkage, surface hardness, bending modulus, tensile strength, impact strength, heat deformation temperature, molding process and dimensional stability of products. Adding high-performance silicon material into plastics can significantly improve the rigidity and creep resistance, hardness and surface scratch resistance, heat resistance and thermal deformation temperature of plastic products; High-performance silicon material with a considerable particle size can also improve the impact strength of plastic products, and it also has a reinforcing effect after being added, which can promote the flow and improve the processing technology of plastics. It also has a remarkable feature and has the role of nucleating agent.

640 (1).jpg

I. Application in Polypropylene Resin (PP)

The unique high-performance silicon material with fine fiber particle size can be used as a reinforcing filler for polypropylene. In the modification system of polypropylene, adding high-performance silicon material can not only significantly improve the rigidity, surface strength, thermal creep resistance, electrical insulation and dimensional stability of polypropylene products, but also improve the impact strength and crystallinity of polypropylene, thus improving the mechanical properties of polypropylene. Moreover, due to the improvement of crystallinity and grain refinement, 20% and 40% high-performance silicon material polypropylene composites can significantly improve the rigidity and high temperature of polypropylene at room temperature and high temperature. In the automobile industry, polypropylene with high-performance silicon material is mainly used for bumper and instrument panel of automobile, and also used for fan cover, heater cover, conduit, battery heat shield, fluid pump, etc. In the aircraft industry, it is used for refrigerator door gasket, heater and vacuum pump cover, washer agitator; In the electrical industry, it is used for injection molding various instrument housings and electrical components, and in the home appliance industry, it is used for injection molding parts such as refrigerator drawers and washing machine drums.

Second, the application in polyethylene resin (PE)

It has certain water resistance and high chemical inertia, so it has good chemical corrosion resistance and sliding property. Polyethylene filled with it can be used as engineering plastic, which has good chemical corrosion resistance and fluidity and can compete with ABS, nylon and polycarbonate. Filling polyethylene with it can improve the following properties: toughness, flexural modulus and torsional modulus; Improve the flexural strength; Reduce that creep tendency at normal temperature and high temperature; Improve the thermal change temperature and dimensional stability; Improve deformation and warpage, and at the same time have lower thermal expansion coefficient; Improve thermal conductivity; Improve the surface hardness and smoothness of molded parts; Improve the mechanical strength of polyethylene. Adding different proportions of high-performance silicon materials will have different effects on the physical properties of polyethylene materials, and the best addition ratio is 10-15%. For polyethylene blown film, adding high-performance silicon material is better than other materials, and it is easy to form and has good manufacturability. Moreover, this film can reduce the oxygen permeability by 80%, which is especially suitable for packaging oily foods, such as peanuts and broad beans, and it will not be oily or spoiled for a long time. This film can reduce the water vapor transmission rate by 70%, and has good moisture resistance, which is very suitable for underground geotextile moisture-proof cloth and packaged food.

Third, the application in ABS resin

ABS resin is an amorphous polymer, which has excellent molding processability like polystyrene. It has good impact strength, good low temperature resistance, high tensile strength and good creep resistance. In order to improve the existing performance of ABS, people have carried out extensive research on ABS modification. For example, the plastic sheet of automobile instrument panel made by blending ABS and PVC, and the leather-like luggage cover made by blending ABS and PVC not only have high strength and toughness, but also can maintain the durability of surface patterns. Filled with superfine calcium carbonate or high-performance silicon material, this blended material can significantly improve the notched impact strength and tear resistance of the blended material. For example, adding high-performance silicon material or calcium carbonate 5-15% can improve the notched impact strength by 2-4 times. Because ABS is an amorphous polymer, it has the function of containing more materials. Adding high-performance silicon material can not only significantly improve the original performance of ABS, but also reduce the cost. Therefore, it is widely used for injection molding shells of various instruments, televisions, tape recorders, mobile phones, etc. Of course, it is also widely used in other fields such as textile equipment, electrical parts, automobile parts, aircraft parts and so on.

Fourth, the application in polystyrene resin (PS)

Unmodified general-purpose polystyrene is an amorphous polymer, which is hard and brittle, but it has good electrical properties, aging resistance and high dimensional stability. The disadvantage is that it is brittle and sensitive to environmental stress cracking. Adding high-performance silicon material can improve impact toughness, adjust rheology and significantly improve flexural modulus. The tensile yield strength is also improved. For example, when 40% high-performance silicon material is added, the flexural modulus increases from 23,800 kg/cm to 58,800 kg/cm, and the tensile strength increases from 336 kg/cm to 385 kg/cm.

640 (2).jpg

V. Application in nylon resin (PA)

For nylon (polyamide), special attention is paid to the toughness and wear resistance of this plastic in industry. Nylon is generally hard, similar to keratin, with good wear resistance and high dimensional stability. These properties can be further improved by fillers or reinforcing agents. The hardness, stiffness, wear resistance and thermal deformation temperature of PA66 are the highest in nylon. PA6 is famous for its high toughness: PA610 has low water absorption and high dimensional stability; PA11 has the highest impact strength in nylon. High-performance silicon material can improve the original good properties of nylon and improve its wear resistance. Compared with metal, unfilled modified nylon has low elastic modulus, low tensile and creep strength, and its mechanical properties are obviously dependent on temperature. The molecule contains amino group of water-absorbing gene, which has high water absorption. The product is easy to absorb water, swell and deform when used, and it does not crystallize completely when it is processed and molded, and it still crystallizes when used, which leads to deformation and even cracking of the product. The above shortcomings of nylon can be greatly improved by adding high-performance silicon material. The high-performance silicon material acts as nucleating agent, and can increase the crystallization rate and crystallinity of nylon after being added, so it can especially improve the toughness, mechanical strength, hardness, thermal stability and dimensional stability of nylon, improve the surface quality and deformation behavior of products, and also have a good impact on moisture absorption, electrical properties and chemical properties.

VI. Application in PVC resin (PVC)

It has been widely used to fill PVC with ordinary powder. For example, when making rigid polyethylene pipes, the amount of calcium carbonate filled can reach 40%, but the tensile strength and impact strength of PVC should be reduced. If high-performance silicon material with average particle size of 5 microns is added to 40-45% by volume, it can be found that the yield strength of the material is even higher than the original fracture strength, which has obvious strengthening effect on PVC system. For the impact strength, the notched impact strength does not decrease basically when the high-performance silicon material is added within 15% by weight, but the notched impact strength decreases, and the flexural modulus can be significantly increased. Ultra-fine powder has a very significant reinforcing effect on polyoxyethylene systems with toughening agents, such as PVC/CPE and PVC/ABS systems.

1115.jpg

VII. Application in other resins

1. Adding high-performance silicon material to fluoropolymer such as PTFE can improve creep strength, wear resistance, toughness, thermal conductivity, compressive strength, hardness, creep tendency and thermal deformability at high temperature.

2. Adding high-performance silicon filler into POM can further improve its toughness.

3. Adding high-performance silicon material into polycarbonate can improve the toughness.

4. Adding high-performance silicon material into polyphenylene sulfide can obtain better processability, lower shrinkage and accurate demoulding size.