Wuhan Handern PVC/ABS Blend System
DATE：2020/7/28 8:57:07 / READ： / SOURCE：This station
Wuhan Handern PVC/ABS Blend System
The blending of PVC and ARS is easy to develop on the basis that it is difficult to balance compatibility and mechanical properties when directly blending PVC with rubber. Using ABS as the impact modifier of PVC can not only greatly improve the initial impact of PVC, but also improve the processing fluidity of PVC. In recent years, with the continuous increase in the output of TV sets and automobiles, the demand for ABS engineering plastics used in TV sets and automobiles and other mechanical equipment has increased. PVC/ABS plastic alloys have improved the flame resistance of ABS. It is of great significance to relieve the tension of ABS raw materials and reduce production costs. ABS is a copolymer of acrylonitrile, butadiene and styrene. Its structure has rigid segments and flexible rubber segments like MBS. From the analysis of the molecular structure, the ABS molecular chain contains a large number of acrylonitrile segments, which have a strong force between the molecules of PVC, and the solubility parameters of the two are similar, which can form a good compatible system. As the PVC content in the PVC/ABS system increases, PVC molecules gradually penetrate into the SAN segment of the ABS molecule to form a continuous phase, while the butadiene segments are dispersed into microscopic rubber particles, forming an obvious "sea island" Two-phase structure, the interface between the two phases is fuzzy, and there is a thick interface layer, indicating that the two phases have good compatibility. When the material is impacted by an external force, because PVC is a brittle material and is a dispersed phase in the blend, it will induce crazing at the two-phase interface, absorbing impact energy, and interfering with the crazing, leading to the termination of the crazing. As the proportion of ABS in the blend increases, that is, the increase in the rubber phase is conducive to the initiation of silver streaks and a large amount of shear bands with the resin phase, which can absorb higher impact energy and make the material have stronger impact toughness However, when the amount of PVC exceeds the amount of ABS too much, the brittleness of PVC is dominant due to the reduction or loss of the role of rubber, and the impact strength of PVCABS alloy decreases with less carbon in ABS. www.handern.com Hollow Board Equipment
The impact strength of PVC/ABS blends is related to the type of matrix selected, the dosage ratio, and processing conditions. Among them, the different rubber content in ABS has the greatest impact on the impact strength of the blend. When blended with ABS with a high content of rubber, the impact strength of the PVC/ABS blend will have a synergistic effect, and the impact strength will be higher; When the content of ABS is low, the impact strength of the blend is low. The dosage of ABS is generally between 8% and 40%. At this time, the impact strength increases with the increase of the dosage of ABS; when the dosage of ABS is further increased, the impact resistance gradually decreases. When the quality ratio of PVC to ABS is 70:30, the impact strength of the cantilever beam reaches 377,4/m, which is nearly 10 times higher than that of the PVC matrix of 43.1/m. www.handern.com Hollow Board Equipment
ABS can also act as a processing aid to a certain extent, improving the processing performance of PVC. ABS is added to PVC. During blending and molding, due to the greater frictional heat and the earlier gelation time, it is easy to obtain a uniform melt, thus accelerating the melting of the blend and reducing the die expansion during extrusion. Increase the strength of the melt and make the processing more stable. www.handern.com Hollow Board Equipment
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