Filling modification of plastics
Plastic sheet production line
Plastic filling modification is the composite of filler, plastic and resin (calculated by 100 parts of resin), so filler is plastic. Generally, the filling amount of filler is large. Sometimes, it can even be said that the consumption of filler in the world accounts for the total amount of plastic. It is an important and indispensable auxiliary material in the material industry. In general, the modification has the following advantages: about 10% of the total, which shows that its consumption is huge. The advantages of plastics filling modification are as follows
(1) Reduce costs. Generally, fillers are cheaper than resins, so adding fillers can greatly reduce the cost of plastics and have obvious economic benefits, which is also the main reason for the wide application of plastics filling modification. Plastic sheet production line www.handern.com
(2) Improve the heat resistance of plastics. The heat resistance of general plastics is low, such as ABS, its long-term service temperature is only about 60C, and most of the fillers belong to inorganic substances, with high heat resistance. Therefore, these fillers can significantly improve the heat resistance of plastics after they are added to the plastics. Another example is PP, when it is not filled, its heat deformation temperature is about 110 ℃, but when it is not filled, its heat deformation temperature is about 110 ℃ After 30% talc powder, the hot deformation temperature can be increased to more than 130 ℃.
(3) Improve the rigidity of plastics. The rigidity of general plastics is poor. For example, the bending modulus of pure PP is about 1000MPa, which is far from meeting the requirements of some parts. After adding 30% talc powder, the bending modulus can reach more than 2000mPa. It can be seen that talc powder has obvious stiffening effect on PP. Plastic sheet production line www.handern.com
(4) Improve the molding processability of plastics. Some fillers can improve the processability of plastics, such as barium sulfate, glass beads and so on, which can improve the fluidity of resin and improve its processability.
(5) Improve the dimensional stability of plastic products and parts. Some plastics have large crystal shrinkage, which leads to large shrinkage rate of products, and it is easy to deform after coming out of the mold, and the size is unstable. After adding filler, the shrinkage rate of plastics can be greatly reduced, so as to improve the dimensional stability of plastic products and parts.
(6) Improve the surface hardness of plastics. Generally, the hardness of plastics is low, and the surface is easy to scratch, which affects the appearance, thus affecting its surface effect and decoration. The hardness of inorganic fillers is higher than that of plastics. Adding inorganic fillers can greatly improve the surface hardness of plastics.
(7) Increase the intensity. The tensile strength of general plastics is not high. After adding inorganic fillers, the tensile strength and bending strength of plastics can be improved within the appropriate range of filling amount, so as to improve the engineering usability of plastics.
(8) Give some functions to plastics, improve the added value of plastics. Some fillers can give some functions to plastics, such as adding talcum powder and calcium carbonate to PP can improve the antistatic performance and printing performance of PP; adding hollow glass beads to plastics can improve the thermal insulation performance of plastics; adding metal particles to plastics can improve the thermal conductivity and conductivity of plastics. Plastic sheet production line www.handern.com
In a word, the plastic filling modification has many advantages and has been widely used, but we should also pay attention to the problems brought by the filling modification, such as: generally, the impact strength should be reduced, the density should be increased, the surface gloss should be decreased, the color saturation should be decreased, and the strength should be greatly reduced after the filling amount is too large. These shortcomings should be fully considered in the formulation design.