The development technology of high-rigidity polypropylene continues to appear, but from a large point of view, the rigidity modification of polypropylene is nothing more than two methods: chemical modification and physical modification. Chemical modification includes copolymerization modification, grafting modification, cross-linking modification, etc., and physical modification includes filling modification, blending modification, nucleation modification, etc.
Among them, nucleation modification is one of the important ways to improve the rigidity of PP and realize PP engineering. It is characterized by changing or interfering with the crystallization process of PP by adding a nucleating agent with a specific structure in the process of PP processing and molding, so as to realize the change of PP crystal structure and grain size at the microscopic level, and achieve the purpose of improving the mechanical properties such as rigidity and strength of PP finished products at the macro level, and at the same time improving and improving the optical properties and thermal properties such as transparency and heat deflection temperature of PP.
Nucleation and rigidity modification technology is to achieve the purpose of improving the rigidity of PP through the nucleation effect of nucleating agent outside the polymerization kettle and in the process of PP processing and molding, so the research on the synthesis and development and application technology of nucleating agent has undoubtedly become the key to PP rigidity modification technology.
Polypropylene rigid-nucleating agent aryl phosphate: homopolymer and copolymer polypropylene are applicable.
Appearance: White powder.
Volatile matter: 05%( wt )
Melting Point: 300
Average particle size: 10-20 m
Polypropylene stiffening nucleating agent Aryl phosphate is an economical and efficient polyolefin additive, which can significantly improve the impact resistance, rigidity, surface gloss, heat deflection temperature and other properties of polyolefin products, and can shorten the molding cycle of products, especially suitable for the rigidity, brightening and impact modification of polypropylene products.
Aryl phosphate stiffens PP according to the principle of promoting polypropylene nucleation, and promotes and improves the crystallization of PP through the presence of fine particles in heterogeneous nucleation, so as to make its grains uniform and fine, so as to improve the rigidity of products.
Product features: It can significantly improve the rigidity of polypropylene and improve the stability of polypropylene. The crystallization temperature can be increased, which reduces the mold operation time, reduces the mold cycle time, and improves production efficiency. It can consolidate and enhance impact resistance, and has good impact resistance at low temperatures.
It can improve heat resistance, and can significantly increase the heat deflection temperature compared to polypropylene without nucleating agent. It will not react chemically with other additives and additives.
Product application: aryl phosphate nucleating agent has no hazard and can be safely used in the food industry. It is suitable for various manufacturing processes, including: injection molding, blow drawing molding, hollow molding, sheet extrusion, thin-wall injection molding, cast film, thermoforming, etc.
Addition method: Arylphosphate is applied in polypropylene with an addition amount of 01-0.4%。The amount of addition is closely related to the material and thickness, and the user can adjust it appropriately according to the actual situation.
This product can be directly added to polypropylene, and for PP powder, aryl phosphate can be added and mixed evenly before the product can be processed. For PP pellets, in order to mix evenly to achieve the best results, it is recommended to use batch operation. Pour the quantitative PP pellets into the mixer, add a small amount of white oil and stir well, so that the nucleating agent is evenly adsorbed on the pellets. The recommended amount of white oil is about 15-2.0ml。
At present, the commercially available phosphate nucleating agents are mainly organophosphate metal salts and their compounds, and the nucleation effect is slightly better than that of DBS nucleating agent. The representative products are NA-11, NA-21 and NA-71 nucleating agents of Asahi Denka Company of Japan, and their structure and characteristics are shown in Table 2. The three nucleating agents can improve the mechanical properties of PP to a certain extent, and the improvement effect on transparency is NA-71, NA-21, NA-11 from large to small, and the low concentration of NA-71 can make PP reach a very low haze (11%), and can be used in the field of film and food packaging, so that the performance of PP is closer to that of engineering plastics. In addition, the three nucleating agents all reduced the melt viscosity of the product, increased the melt flow rate, and improved the processing performance of PP.
Na-21 is better than sorbitol nucleating agent 3988 and NX8000 in terms of rigidity and thermal properties of modified PP, and has good precipitation resistance, but the improvement of PP transparency is not as good as NX8000 and 3988.
The effects of aryl phosphate (HK001) on the transparency and mechanical properties of IPP and CPP were studied, and the results showed that the 001 nucleating agent had a good permeability and rigidity effect, which reduced the haze of PP by 30%, increased the flexural modulus by 40%, and increased the load deformation temperature by about 20°C. For CPP, HBP series nucleating agent has better rigidity effect, which increases the flexural modulus of PP by 35%, increases the load deformation temperature by 30°C, and increases the notched impact strength of cantilever beam by 27%, which is better than NA-21.
The homobenzamide compound HK002 has good selectivity and thermal stability, and can promote the formation of crystals in IPP. When the addition amount is 0At 02% (W), PP can be made very transparent. In addition, some compounds can also promote the formation of crystals, so that the hardness of PP can be improved to a certain extent.